- cctalk - classiccmp.org

by Holm Tiffe

Hi there, at the beginning of the 90ies I've repaired some Esprit Opus220 terminals for an local computer shop. Problem #1 of those seriaal terminals was a bad the Flyback Transformer. The Shop managed to get a bunch of those FBT's new from Taiwan so I could successfully repair approx 10 of those terminals. I'm still own one of them, still in functional condition (orange 12 or 14" CRT).. My stash of goods should still contain two of those Replacement FBT's, but after a move in 2020 I have to locate them.. So far so good. Now the Problem: I have an Grundig CD313 monitor from an CNC EDM Machine on the table, the FBT Grundig 29200-003.05 is bad and I want to repair the monitor for the small company owning that machine. Unfortunaltely they are located some miles away from me.. My hope is to locate the two new FBTs and adapt one of them into the Grundig CD313 Monitor..where I have the schematics for. It where pretty nice if I could get the schematics from one of that Esprit Opus II (220) Terminals to look at the wiring for the FBT ..and that's my problem.. has anyone the scheamtics for those Opus terminals? Regards, Holm -- Technik Service u. Handel Tiffe, www.tsht.de, Holm Tiffe, Goethestrasse 15, 09569 Oederan, USt-Id: DE253710583 info(a)tsht.de Tel +49 37292 709778 Mobil: 0172 8790 741

7 months, 4 weeks

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Any Interacts out there? 1978, 8080-based system

by Steve Lewis

Checking on if anyone has an old Interact system out there. It wasn't widely successful, but gained some popularity around Ann Arbor, MI. I've not come across one of these yet. But I've come across one of its "Killer Application", a tape-based program called Message Center that lets users construct banner message scripts with a few video/audio effects. Would be interested to see this "for real" rather than just in the MAME emulator. Or also to hear any stories about the system, such as anyone who actually used one, or saw one being used at a storefront? -Steve

7 months, 4 weeks

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IBM 5110 news - RWS memory replacements

by Steve Lewis

Well, just yesterday I tested a set of RWS (RAM) replacement cards for the IBM 5110 from Patrick Lebbard from Canada - and I'm very impressed. They work well, I had them running for a few hours. Details are described here: https://voidstar.blog/ibm-5110-rws-ram-modern-make-replacements/ or VCF thread https://forum.vcfed.org/index.php?threads/ibm-5110-ram-timings.1253087/ I don't think he plans on becoming a retailer, they've offered up the schematic and such. But he did make these boards for me after I shipped him a set of the base connectors that you need (to adapt them to the 5110's A1 board) that I pulled from a known-broken board. His motivation is that he does have a 5100 also that he's trying to resurrect, so he plans to carry on and make an IBM 5100 version of these modules also (still resolving a few technical differences between them, so it's not working out just yet - but the 5110 version of these I can say seem flawless). Anyway, exciting stuff to see someone technically savvy enough to probe signals and reverse engineer 50+ year old tech! -Steve

8 months

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Re: IBM 5110 IMFs

by Robert Marinelli

I've been digging through CHM and bitsavers and haven't found an IMF for 5100 or 5110 yet. It seems a lot of CE material was just not saved. However, I've been tracing execution of ExecROS and the APL ROS - thanks to your excellent emulator and the extracted ROS files this works well. Have learned a few things about the jump tables, I'd imagine that the type 23 files would likely install themselves in high memory and modify an IOCB jump entry to point to the new/patch code. Kind of like how you take over the printer IOCB. One little issue I found with your emulator is behavior of interrupts while in HOLD. Per the APL and BASIC manuals, pressing HOLD while a program is running should pause the output (mostly so you can read the screen before output scrolls up), and then pressing HOLD again is supposed to continue execution. In emu5110 that didn't work, pressing HOLD always stopped but a 2nd press wanders off in to never land (hang or bogus error or junk on screen). While tracing & learning I noticed that if code was being executed from one of the language ROS, HOLD would fail. But HOLD/resume worked fine on an idle machine - idle is a short loop that just blinks the _ cursor at location 0x0200+902 in APL. So looking through the pseudo-schematics/block diagrams in SY31-0552-3 IBM 5110 System Logic there is quite a bit of gate logic on the multiple ROS cards, plenty of wires between them. Maybe, hardware interrupts are held off in hardware when we are doing reads from the language ROS cards. The interrupt bits are properly shown in a register, but nothing detailing gating of interrupt -> CPU. To test the idea I made this change in emu.c: 175c175,176 < check_int(); /* check for pending interrupts */ --- >if(curr_ros==ExecROS) /* if in ExecROS we can HOLD/resume */ > check_int(); /* check for pending interrupts */ and now HOLD works as expected. Norbert's JavaScript port had the same issue with HOLD, he ported the above and confirmed that the HOLD now works properly. As a side note, the MAME emulation (which may have been done independently) has the same problem, likely could use the same fix. Anyone know how to contact the MAME author? There was a lot of interest in the CHM release of APL\360 source along with auto-operator and I've tried contact a few of those folks, we just need one CE or user who kept a box of floppies. -Robert

8 months

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50 years of the MOS 6502

by Christian Liendo

https://www.allaboutcircuits.com/news/the-mos-6502-how-a-25-chip-sparked-a-… According to many 50 years ago on September 16, 1975, MOS Technology showed the 6502 at WESCON

8 months

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VCFMW20 recap of highlights

by Steve Lewis

VCFMW in Chicago was this past weekend! Flew up with 2 bags, came back with 4 ! Funny thing is, my wife said she was surprised I didn't come back with anything extra - well, I shipped those extra 2 bags and they haven't shown up yet. Gives me one day to come up with a cover story! :) There is so much going on at the Chicago VCF - I don't think any individual can cover the whole thing. Instead of a blog, this time I'm trying a "video photo album" to cover some of the highlights that I was able to see. Search Xiphod's Photo Album of Vintage Computer Fest (no commentary) - VCF Chicago 2025 or https://www.youtube.com/watch?v=ld1CXUTusDI or https://rumble.com/v6z4aia-xiphods-photo-album-of-vintage-computer-fest-no-… Mainly my goal was to pick up a POLY-88 that folks have been helping to restore off-and-on over the past 18 months. They got it going, so that was one of the shipments back. The other was an Apple TAM at too good a price to pass up. (and yes, wife already knows they are coming) If it's any indicator: come Sunday afternoon, merchants were fairly eager to sell at any offer (some announcing that anything unsold would go straight to scrap - maybe that's a ploy, but there were some under $10 bargains to be had, a kind of "everything must go" vibe). - Steve

8 months

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Fun with PDP11 Assembly Language

by Martin Eberhard

I just love the PDP11's assembly language. I needed a super-tight subroutine to print a 16-bit value as 6 octal digits. This is as tight as I could make it, 16 words (including writing to the serial port, which takes 5 words). Can you beat it? ;*** Subroutine ************************* ;Print a 16-bit value as 6 octal digits ;Calling Sequence: ; jsr PC,PROCT6 ;On Entry: ; R2 = value to print ;Trashes R1,R2 ;**************************************** PROCT6: mov #100030,R1 ;Digit loop ends when '1' lands in C ;..'30' makes it ASCII sec ;All done when this is in C again ;Extract a digit and convert it to ASCII. Check for done. 1$: rol R2 ;Shift digit out of R2 & into R1 beq 3$ ;Return when done rol r1 ;Build next octal digit bcc 1$ ;Done when c = shift pattern bit ;Write digit to the serial port 2$: tstb @#CTXSTA ;Wait for transmitter (clears C) bpl 2$ movb R1,@#CTXDAT ;Transmit now ;Next digit mov #020006,R1 ;Digit ends when "2" lands in C. ;Printing ends when "sec" bit ;..leaves R2. '6' makes ASCII br 1$ 3$: rts PC Martin E.

8 months

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Ohio scientific boot discs

by George Rachor

Looking for both 8 inch and 5.25 inch boot media. Sent from my iPhone george(a)rachors.com

8 months

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Huntsville Microsystem HMI-200 emulators

by Tony Jones

Crazy long shot. I just picked up a HMI-200-64180 for $75 shipped. Curious if anyone has the manual and software for it? There is some very limited info on bit savers but nothing for the 64180. I'd also possibly be interested in picking up the 6809 version if anyone has one they no longer need and the price is fair. https://web.archive.org/web/19980206071507/http://www.hmi.com/200.html Thanks

8 months

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Large language model (LLM) Web Scrapers

by Bill Degnan

For those of you who run vintage computing-related info sites, have you noticed all of the LLM scraper activity? AI services are using the LLM scrapers to populate their knowledge bases. At any given moment 5-10 of them are active on vintagecomputer.net. It’s funny, when I ask an AI about something vintage computing-related, something obscure, I can trick into giving me an answer from my own site. I have actually had to modify the site code to manage the traffic, to improve efficiency. But they’re not going after just my site, these scrapers are absorbing copies of the entire WWW. I wonder how long the WWW will remain open, it would be a bummer if I found copies of my site elsewhere. Bill

8 months

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Need a Connectix quick cam?

by Van Snyder

I have a Connectix quick cam. The on ly label says FCC ID LKD1. The connector is a mini-DIN that looks like a PS-2 mouse or keyboard plug. Do you need it?

8 months, 1 week

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Re: [List] Re: Fun with PDP11 Assembly Language

by donald donaldwhittemore.com

You want blinky lights? Try this. 😊 https://www.chilton-computing.org.uk/ca/jpgs/195_engineers_console.jpg

8 months, 1 week

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Re: CTOS Ethernet EDL software

by Alexei Iliasov

The driver package (B25-PDL_CTOS_Ethernet_Packet_Driver_3.7.0) also has drivers for ACCTON 1660 and 3COM 3C509 - you need to uncomment them in JCL file. I have the Accton card installed and detected in dos (and confirmed IRQ and base address) on SG3000 platform but activating the driver always crashes CTOS to core dump. The only suspect bit “Shared memory” which appears to be boot room address and this is not installed on my card (socket missing). Wonder if anyone had success with the driver?

8 months, 1 week

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Magellan Roadmate X11-16302

by Van Snyder

Free to good home: I re-found a Magellan Roadmate X11-16302 GPS map in my junk heap. It appears to have a dead battery, at least it appeared not to charge on USB. I don't have the AC power cube or the car's cigar-lighter power adapter. Send a PDF for a shipping label from Van Snyder 2229 Shields Street La Crescenta, CA 91214 Local pick up OK too.

8 months, 1 week

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Repairing an Olivetti M24 PSU

by Robert Jarratt

My Olivetti M24 was humming away nicely until I switched it off. It then failed to power on again. The PSU is not outputting any voltages on any of its outputs. The technical manual is here https://bitsavers.org/pdf/olivetti/m21_m24/Olivetti_M21_M24_Theory_of_Opera…. The PSU is described from p188 with an outline schematic on p194. The full schematic is on p274. A schematic useful to anyone with the actual board in front of them has been created in the following forum post https://forum.vcfed.org/index.php?t...ower-supply-replacement.1237316/#post…, the schematic is this one: https://forum.vcfed.org/index.php?attachments/m24_psu_schematic-jpg.1252584/. I have done some verification with the scope but I have reached a point where I am not sure what signals I should expect. I have attached a dummy load on the +12V, +5V and +15V outputs to meet the specs for minimum current. I see a 20KHz square wave on the inputs to the output transformer T438 (pins 1 and 2). The manual says that the diodes on the output rectify a half wave. I assume these are the ones labelled D134 and D136. The following image shows the signal on the two diodes marked D134 on the schematic for the 12V output, measured from their anodes to 0V output. https://rjarratt.wordpress.com/wp-content/uploads/2025/08/diodes-on-12v-out… For the other two diodes, labelled D136 for the 5V output I get this: https://rjarratt.wordpress.com/wp-content/uploads/2025/08/diodes-on-5v-outp… Do these look correct? The peaks seem to be too low to even begin to produce the required output voltage. Thanks Rob

8 months, 1 week

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VCFMW

by Paul Anderson

I' plan on arriving there between 1 and 2 Friday afternoon. If there is anything else you want me to bring please email me off list today. If you have any US/ foreign coins/currency I'm interested in trading or buying them. Thanks, Paul

8 months, 1 week

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UK - Northwest Computer Museum Jumble Sale

by David Wade

Folks, The Northwest Computer Museum in Leigh, Lancashire is having a jumble sale this coming Saturday. https://www.facebook.com/events/leigh-spinners-mill/tech-jumble-sale/129448… They have said I can have a table as well so I will be bringing along some of my /junk /oops surplus bits and bobs. I will have floppy disks, floppy disk drives, disk drives, keyboards, bits of Sun SPARC station, RS232 leads, PCI cards.. .. all "as seen" , most for donations to the Museum... Dave

8 months, 2 weeks

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Going to e-waste unless somebody wants them

by Van Snyder

Time to clean out my basement. These are going to e-waste unless somebody wants them: Compaq Presario SR1010NX. Don't know whether it works. HP desktop box with MB and PS, no DVD, not working. Dell power supplies for data center clusters: 4 × N750P-50. 1 × PS- 2521-1D 2 × CC8823 power supplies for network switches (don't know the manufacturer; 3Com?) 3 × Ultrium fiber-channel tape drives. and a few cartridges PowerOne switching power supply Model SPM5A2M6G1K, 1 × 48VDC @ 5A, 3 × 12VDC @ 10A, 1 × 5 VDC @ 150A. Local pick-up in La Crescenta, CA is OK.

8 months, 2 weeks

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Going to e-waste unless somebody wants them

by Van Snyder

Time to clean out my basement. These are going to e-waste unless somebody wants them: Compaq Presario SR1010NX. Don't know whether it works. HP desktop box with MB and PS, no DVD, not working. Dell power supplies for data center clusters: 4 × N750P-50. 1 × PS- 2521-1D 3 × Ultrium fiber-channel tape drives. and a few cartridges PowerOne switching power supply Model SPM5A2M6G1K, 1 × 48VDC @ 5A, 3 × 12VDC @ 10A, 1 × 5 VDC @ 150A. Local pick-up in La Crescenta, CA is OK.

8 months, 2 weeks

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Back to the Philips P3800

by Tony Duell

Some months back I started working on a Philips P3800 computer, there was a long discussion here about the power switch and its unusual cylinder lock. At least one person was interested enough in the lock to say they would like to see it with a view to making a key At the time I didn't want to post the lock anywhere as I could have been left with a incomplete and unrepairable machine. Other projects, some of them classic-computer related got in the way. but over the last few days I've gone back to the P3800 and have made a spindle to effectively replace this lock and allow the power switch to be knob-operated (security is not an issue in my workshop :-)). Thus I could manage without the lock if I have to. So if the offer is still open I would consider posting the lock somewhere (preferably in .uk) Obviously it's 'work on it as and when you feel like it'. There's a lot of electronics for me to work on, and I'll probably take many months to sort that out. -tony

8 months, 2 weeks

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Datapoint 2200 needing a home (and restoration)

by Steve Lewis

Just relaying a message here, for those who maybe don't requent the VCF forum itself. A 1st-post person says he's original owner of a Datapoint 2200, and is looking to find a good owner (museum) for it. Not sure where he is presently located, but the CRT of this DP needs attention - and I'm fairly useless in that department. In the Genre|Others section. https://forum.vcfed.org/index.php?threads/new-datapoint-2200-owner.1244800/… May be a pre "A" or "B" version, since it has the original tape decks at top? In any case, likely a pre-1974 model for sure. -Steve

8 months, 2 weeks

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BASIC

by Murray McCullough

I read that B. Gates has released 'BASIC for 6502 Microprocessor - Version 1.1' that has 6955 lines of assembly language code. I would say this qualifies as a major event in the classic computing world. Happy computing! Murray 🙂

8 months, 2 weeks

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Compaq Presario?

by Van Snyder

This might be the wrong list to ask, but here's the question: I have a Compaq Presario gathering dust in my garage. Does anybody want it? Shipping might cost more than its value, but local pickup is OK with me. Van Snyder La Crescenta, CA

8 months, 2 weeks

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Do not miss your chance to exhibit at VCF Montreal in 2026!

by Jeffrey Brace

The show is Jan 24-25, 2026. Info here: https://vcfed.org/vcf-montreal/ Exhibit Registration is here: https://docs.google.com/forms/d/e/1FAIpQLSc4dnGLg9Ubt3gSxNNcOukTIhTNZZK2dQB… Ne manquez pas votre chance d’exposer au VCF Montréal en 2026 ! #VCFMTL https://docs.google.com/forms/d/e/1FAIpQLSc4dnGLg9Ubt3gSxNNcOukTIhTNZZK2dQB… Take care! Jeff Brace VCF National Board Member Chairman & Vice President VCF East Showrunner VCF/MARCH Fundraising Manager VCF Evangelist Vintage Computer Federation is a 501c3 charity https://vcfed.org/ <http://www.vcfed.org/>

8 months, 2 weeks

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IBM Punched Card Equipment

by Brian L. Stuart

Apologies in advance to anyone who gets this multiple times. I know a number of you are on more that one of these lists. I'm looking for some information on a couple of the early IBM unit record devices, in particular the Type 512A and the Type 518. Ideally, I'd like to get the mechanical dimensions in enough detail to create a CAD model. The background is that I'd like to improve the model that I'm using in my ENIAC simulator and I'm involved with a school in Arizona that's working on a project to build a full-scale model of the ENIAC. There's a letter from IBM in the ENIAC archives that suggest the use of the 512A and the 518. So I'm pretty sure those are the ones they used, but I haven't really been able to find any details about them. We've found a fair amount of information on the Type 513, and from photographs, the punch used on the machine seems similar to the 513, but is smaller. Thanks in advance, BLS

8 months, 2 weeks

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Bringing BASIC back: Microsoft’s 6502 BASIC is now Open Source

by Christian Liendo

Looks like Microsoft is opening their 6502 Basic https://opensource.microsoft.com/blog/2025/09/03/microsoft-open-source-hist… Today, we’re opening the vault—for real. For decades, fragments and unofficial copies of Microsoft’s 6502 BASIC have circulated online, mirrored on retrocomputing sites, and preserved in museum archives. Coders have studied the code, rebuilt it, and even run it in modern systems. Today, for the first time, we’re opening the hatch and officially releasing the code under an open-source license. Discover the newly open-sourced Microsoft 6502 BASIC code Microsoft’s first products: From the Altair to the Commodore 64 Microsoft BASIC began in 1975 as the company’s very first product: a BASIC interpreter for the Intel 8080, written by Bill Gates and Paul Allen for the Altair 8800. That codebase was soon adapted to run on other 8-bit CPUs, including the MOS 6502, Motorola 6800, and 6809. You can learn more about this time and hear directly from Bill Gates on the Microsoft Learn Website’s History of Microsoft video series or by visiting Bill Gates’ blog. The 6502 port was completed in 1976 by Bill Gates and Ric Weiland. In 1977, Commodore licensed it for a flat fee of $25,000, a deal that placed Microsoft BASIC at the heart of Commodore’s PET computers and, later, the VIC-20 and Commodore 64. That decision put Microsoft’s BASIC at the heart of Commodore’s machines and helped millions of new programmers learn by typing: 10 PRINT “HELLO” 20 GOTO 10 This is BASIC M6502 8K VER 1.1, the 6502 BASIC lineage that powered an era of home computing and formed the foundation of Commodore BASIC in the PET, VIC-20, and the legendary Commodore 64. This very source tree also contains adaptations for the Apple II (“Applesoft BASIC”), built from the same core BASIC source. The original headers still read, “BASIC M6502 8K VER 1.1 BY MICRO-SOFT”—a time capsule from 1978. The version we are releasing here—labeled “1.1”—contains fixes to the garbage collector identified by Commodore and jointly implemented in 1978 by Commodore engineer John Feagans and Bill Gates, when Feagans traveled to Microsoft’s Bellevue offices. This is the version that shipped as the PET’s “BASIC V2.” It even contains a playful Bill Gates Easter egg, hidden in the labels STORDO and STORD0, which Gates himself confirmed in 2010. The enduring appeal of the MOS 6502 CPU The MOS 6502 was the CPU behind the Apple II, Commodore 8-bit series, Atari 2600, Nintendo Entertainment System, and many more. Its simplicity, efficiency, and influence still inspire educators, hobbyists, and hardware tinkerers today. In 2025, interest is as strong as ever. The retro-computing scene is thriving, with FPGA-based re-creations, emulator projects, and active development communities. The Commodore brand has returned with the announcement of a new FPGA-powered Commodore 64, the first official Commodore hardware in decades. Reconstructing and preserving Microsoft BASIC Over the years, dedicated preservationists have reconstructed build environments and verified that the historical source can still produce byte-exact ROMs. Notably, Michael Steil documented and rebuilt the original BASIC process for multiple targets. He has ported the code to assemblers like cc65, making it possible to build and run on modern systems. This open-source release builds on that work, now with a clear, modern license. It follows Microsoft’s earlier release of GW-BASIC, which descended from the same lineage and shipped in the original IBM PC’s ROM. That code evolved into QBASIC, and later Visual Basic, which remains a supported language for Windows application development to this day. From the blinking cursor of 1977 to FPGA builds in 2025, BASIC still fits in your hand. Now, for the first time, this influential 6502 version is truly yours to explore, modify, and share.

8 months, 2 weeks

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List of PDP-8 omnibus boards available at VCFMW or shipped.

by Paul Anderson

M1705 M518 M7741 M8342 M835 M8350 M8360 M8357 M8365 M8366 M837 M839 M841 M847 M849 M860 M8650 M8659-YA M865 M8652 M8653 M8655 M866 M868 M884 M885 M880//H241 MR8E-EC Also CR8- an actual DEC card reader interface, dec industrial control equipment,EMEX paper tape interfaces, and other dec compatible boards including memory.

8 months, 3 weeks

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WIN 95

by Murray McCullough

Microsoft released WIN 95 on this day 30 years ago. It was a game changer for the average PC computer user but more important than Windows 3.1? Not so sure. Happy computing, Murray 🙂

8 months, 3 weeks

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The Sharp PC-5000 Video

by Steve Lewis

Hey all, after a couple years of prep (weekends here and there), I've finally finished a full coverage video about the Sharp PC-5000. It's not the most meaningful system in history, but it also shows the "MS-DOS 2.0 experience" and bubble memory usage. Various folks around here helped me figure this system out and get some of the equipment, very much appreciated the willingness-to-help community here. Video is on YouTube titled as: Sharp PC-5000 and MS-DOS 2.0 Usage Demonstration (EDLIN, CTTY, MASM, BASIC, Pascal, WordStar, more!) Or link... https://www.youtube.com/watch?v=dHPiomuWDmk And to those who can't use YouTube for whatever reason, I've started also uploading over on Rumble as an alternative source: https://rumble.com/v6ybfky-sharp-pc-5000-and-ms-dos-2.0-usage-demonstration… I'll be at VCF MW coming up, hoping to pick up another system that I've been wanting to explore for a long time! Not sure yet it works, but that's how the hobby goes :) - Steve (voidstar tech / Xiphod)

8 months, 3 weeks

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Message trimming/formatting

by Marvin Johnston

There seems to be a LOT more people who don't believe in trimming or formatting their copies of the messages they are replying to. I see that kind of obvious disrespect for other readers, and ignored it for a while. But it is getting worse. Please format/trim when replying. Marvin

8 months, 3 weeks

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5155 lugable

by Bill Gunshannon

I finally got the missing keyboard and now it is time to try and revive it. A couple quick questions. It has a board in it called IBM PC INTERFACE with the numbers 170-18-165 and CIL18-16 printed on it. It has a 50 pin connector on the bracket end. If I take it out the machine dies almost immediately doing the POST. Tried Google with no luck. Anybody remember what it is? Next problem. 1701 error. Light on MFM drive flashes 3 slow and 4 fast continuously. Being as this machine was known to work when it was last shut down any suggestions? Could it be a stiction problem and the disk just isn't spinning up? (Can't tell by listening as the fan is pretty loud. Not bad just louder than any good disk I have ever heard.) And then one other not related to a problem. Being an original PC owned by users and not geeks is it likely that the floppy controller is one that can handle other formats (like TRS-80) and maybe even 8"? And just to wrap it up. What are the chances of finding an external drive or even a cable that could be made to connect to an external drive? Really hoping to get it to run. Would love to see what the Psychology Department had on it. At least WordPerfect as there is one of those function key templates taped on the keyboard. bill

8 months, 3 weeks

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Re: Tesla's Forgotten Founder Speaks Out - Exclusive w/ Martin Eberhard

by Shoppa, Tim

Frank wrote: > I wasn’t around back then ;) But I think the big problem with > steam tractors was since they were so heavy they would sink into > the fields. I don’t think that was an issue really solved until gas > powered tractors came around. We're getting off topic but I want to interject that if you want to see operating steam tractors, stationary steam engines, and lots more, get to Mt Pleasant Iowa RIGHT NOW for the annual Old Thresher's Reunion which starts TODAY. I note that when the Old Thresher's Reunion first started in 1950, the steam tractors being run there were only 40-50 years old, not too dissimilar to how an Apple II or PDP-11 is today. https://www.youtube.com/watch?v=hs4L2nSqCL4 https://www.oldthreshers.org/other-events/steam-school/ Tim N3QE

8 months, 3 weeks

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Tesla's Forgotten Founder Speaks Out - Exclusive w/ Martin Eberhard

by Kirk Davis

Interesting for Tesla’s early history, but skip to 49:00 for a nice rack he is putting together with an 11/20. https://youtu.be/88KHfX_kPIY He also appears to be on the cctalk list.

8 months, 3 weeks

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Need 3.5" drives?

by Van Snyder

I have some 3.5" drives I don't need. One 350 GB PATA Three 320 GB SATA One 500 GB SATA Yours in exchange for a PDF of a shipping label from Van Snyder 2229 Shields Street La Crescenta, CA 91214 Local pickup also OK. Just say which ones you want. They all have smartctl reports that claim they passed.

8 months, 3 weeks

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CII1040 ..what exactly is this?

by Holm Tiffe

Hi guys, I'm somewhat sorting my stash of forever laying around parts and there are 12 pcs from those: https://www.tiffe.de/images/CII1040.jpg That are two PNP BJTs in an TO can..and I think they are old. I've desoldered them years ago. Most of them have an TI logo printed on top. I could'nt find any data..can someone help here? Thx, Holm -- Technik Service u. Handel Tiffe, www.tsht.de, Holm Tiffe, Goethestrasse 15, 09569 Oederan, USt-Id: DE253710583 info(a)tsht.de Tel +49 37292 709778 Mobil: 0172 8790 741

8 months, 4 weeks

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Re: Tesla's Forgotten Founder Speaks Out - Exclusive w/ Martin Eberhard

by donald donaldwhittemore.com

This is one of a few websites where ‘nice rack’ has a totally different meaning. 😊

8 months, 4 weeks

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Chuck Guzis -- Equipment and Archive

by Chuck Guzis

I am Michael St. Clair, Chuck's nephew by marriage. I'm writing from his account to establish bona fides; apologies for any surprise it might cause. You appear to be the people he considered his professional peers, so I'm reaching out to you for some help. Chuck had little warning before he passed. He left his equipment and development environments in working order, but without a legacy plan. I'm a software engineer and data archivist, and my aunt has asked me to find good homes for his equipment and IP. I'm going to organize and open-source the software and other IP that he hadn't already released. However, I don't know how to safely use, maintain, or even store his physical gear. I'm only in Eugene for a couple more days on this particular trip. is there any specific physical information (that doesn't require disassembly) that might be useful to potential adopters? I don't have time to make a complete inventory, but here's a list of highlights and a Drive folder containing some photographs. This is not (yet) a formal "come and get it" offer, but it's likely a prelude to one (excluding business documents and computers). Highlights: - Multiple 8-inch floppy drives in built-like-a-truck housings - Dozens of assorted 80s and 90s-era I/O devices -- ZIP drives, 5 1/4" readers, etc. - rack-mounted HP 7970B tape drive - another full-height rack-mounted 9-track tape drive with external control panel; no manufacturer or model number on anything I can get to - custom-built 'tape dehydrator' - around a thousand pieces of assorted removable media, primarily 3.5", 5 1/4", 8", CD, DVD, and a variety of late-90s and 00s digital tape formats. Per labels and spot-checks, their contents range from widely-distributed commercial software to Sydex master floppies to lost BASIC dialects to industrial control software in CP/M formats. Basically 25 years of Chuck's professional life and the industry around it. - full electronics workbench with partially-finished projects, including something involving Pertec controllers - a variety of functioning vintage keyboards, from IBM Model Ms to something apparently taken from an industrial control station. Drive folder: https://drive.google.com/drive/u/1/folders/1KUs-x6t4OtzS_b7lxYMM7i-GxNi-QRv3 I'd very much appreciate any input. -- Michael St. Clair

8 months, 4 weeks

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Re: Chuck Guzis -- Equipment and Archive

by Gravity Loop

Hi Magnus, Thanks for the link but as I said, this is a field that is still under researched with a lot of misinformation out there especially on the less academic or lab side of things. I understand this stuff and the processes but I am here to help other people understand and acquire these skills for the future. The thing is, if he has custom equipment for it he may have also documented a reliable workflow that could be used in smaller operations, at home setups, etc. I'm looking to further disseminate information as well as continue the research outside of corporate interests. Making sure knowledge is handed off and widely available, including in print form. So while your helping spirit is definitely appreciated, as a professional audio engineer I'm explaining the state of things outside of lab preservation. Not to mention, you can read posts online by professionals even talking trash on the stuff linked. This is exactly how I found out about Chuck years ago. I'm chiming in here because I'm specifically interested in the knowledge Chuck collected, preserving any techniques he hammered into followable steps or additional knowledge not spread, and to share in more ways for others that didn't liaten or haven't figured it out yet. He was someone who knew a lot of tricks and helped a lot of people. - Lichen

9 months

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Any interest in any of this at VCFMW?

by Paul Anderson

If you have any questions or wish to contact me, Please email me directly at useddec(a)gmail.com. 42" cab with BA23 microvaxII, plus additional BA23 42" cab with 2 RL02 drives, outer case for 11/23 and you pick which Qbus box you want with it and what boards you want in it. 42"cab with RL02 RAMTEK Marquis model III with Compugraphic monitor HP7475 plotter LA36 with Datasouth board 120cpm LA100 LA12 with carrying case Darkroom equipment including Omega B22, D2, other enlargers, timers, tanks, trays, etc. I can text photos of any of these items and anything I have listed, but have problems posting them. If you have any US or foreign coins or currency, I'm interested in trading for computer equipment. If you are interested in stopping here before or after VCFMW, or when you are in the area, let me know so we can set up a time. I'm outside Champaign, IL, with easy access to I-57, I-72, and I-74. Thanks, Paul

9 months

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Anybody need a Pentium III MB?

by Van Snyder

I have a Supermicro P3TDDE MB. It has two processors with their fans, and four USA DEM DO133-065651I 64x64 133-222 memory sticks. Also the ATX plate for the back, and a Matrox dual-VGA graphics card. All yours for a PDF of a shipping label.

9 months

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BLACK BOX SP400A-R3 and SP340A-R2 opto isolators

by Holm Tiffe

Hi all, A customer has a problem with an old CNC Mill that uses an LSI11 for control. There is an DEC VT510 connected to the LSI11 as console, The LSI11 is booting from an RX01 (2?) and uses some basic programm.. pretty much a museum... The problem is, that on the Sigma Systems serial Card (similar to the M8043) the AM26LS32 receiver is going bad afer some on/off cycles of the computer. I've already fitted a socket for the 26LS32.. The AM26LS23 only could tolerate +-7V common mode voltage difference and seems to be not the best part for RS232.. I've checked the terminal and changed in the meantime the X2 and X capacitors at the line filter, the protective earth from the Line is connected to the Pin 7 (singal Ground) of the DB25 Connectors and I could'nt measure realy potential differences that could be the cause for the damadge of the receiver chip. To make it short..chase away the problem I wan't to use some RS232 Opto Isolator in the RS232 Line. I've got a used BLACK BOX SP340A-R2 and an SP400A-R3 from Ebay, additional some Power Injector from BLACK BOX for powering that with some wall wart that wasn't included. I've now looking for a Manuals for the BACK BOX SP340A and the SP400A to configure the dip switches in there. There are 2 DIP Switches with 8 positions each..for configuring the power supply for the opto couplers from the DB25 connectors it seems. Haven't found anyithing related on bitsavers, there is blackBox in the communication archive, but nothing related to the SP340 oder SP400.. Can anybody help please? Regards, Holm -- Technik Service u. Handel Tiffe, www.tsht.de, Holm Tiffe, Goethestrasse 15, 09569 Oederan, USt-Id: DE253710583 info(a)tsht.de Tel +49 37292 709778 Mobil: 0172 8790 741

9 months

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Someone posted about old "CSM Core" Board on Reddit

by Christian Liendo

It looks like they may be looking to let them go. https://www.reddit.com/r/vintagecomputing/comments/1mv17hn/197274_boards/

9 months

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PDP-8/s Engineering Drawings?

by Tom Hunter

I have recently bought a DEC PDP-8/s. It hasn't been powered on for about 40 years before I got it. I cleaned it and did some repairs on it (glued broken flip-chip handles, replaced all front panel lights, restored the acrylic front panel to as new condition and built a new switch mode power supply for +10V and -15V). After testing each flip-chip individually for dead shorts on the power rails I reassembled the flip-chips into the backplane and on power up it shows signs of life, but has a number of problems I will have to debug and fix. Does anyone here have the original Engineering Drawings or good PDF scans of the drawings? There are reduced copies of the PDP-8/s Engineering Drawings in Appendix A of the two PDP-8/s Maintenance Manuals on Bitsavers, but I have not been able to find scans of the actual Engineering Drawings. Some details in the reduced copies in Appendix A are not legible. Thank you Tom

9 months

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3.5" DD disks, NOS, $10 pack of 10

by Anders Nelson

Found earlier today: https://www.facebook.com/share/16ubJMkAzw/ I was looking for an affordable source of 720K disks before I sold my 5140 so my instinct kicked in haha. -- Anders Nelson

9 months

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DeVry Trainer exhibited at HOPE

by Jeffrey Brace

Bill Degnan had asked in a previous message about the DeVry Trainer that we exhibited at HOPE_16. The trainer is labeled: De Vry Institute of Technology Bell & Howell Schools We don't have a lot of information about it. Like the year that it was created, who manufactured it, who used it, home many were made, etc. The usual information that you would put on an info card for an artifact. Here is a picture: https://vcfed.org/wp-content/uploads/2025/08/DeVry_Institute_of_Technology_… Enjoy! Jeff Brace

9 months

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Re: VCF/MARCH at HOPE August 15-17

by John Klos

> VCF/MARCH will have 5 tables this weekend Aug 15-17 at HOPE (hope.net > <http://hope.net/?fbclid=IwZXh0bgNhZW0CMTAAYnJpZBExMFdyWUcwTTFHMUkwOHRqNwEeW…>) > in Jamaica, Queens at St. John's University. > Please stop by if you are in the area! > List of artifacts on display: > Lawrence Livermore (in a briefcase), 8080 processor. > Heathkit trainer ET 3400. > TTL Trainer > Devry Trainer > 555 Timer > HP 5036-A > TRS-80 Model III or IV > Commodore PET > IBM P-70 - Luggage > IBM Portable - 5140 > Pong! > Atari 5200 > Bally Astrocade > Fairchild Channel F > We will be promoting our events and local group. I'd love to stop by, but $250 is one hell of an entrance fee. John

9 months, 1 week

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Re: VCF/MARCH at HOPE August 15-17

by donald donaldwhittemore.com

I went to DeVry. What is a DeVry Trainer?

9 months, 1 week

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Re: VCF/MARCH at HOPE August 15-17

by donald donaldwhittemore.com

I graduated in 1969. Guess I missed them. :)

9 months, 1 week

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VCF/MARCH at HOPE August 15-17

by Jeffrey Brace

VCF/MARCH will have 5 tables this weekend Aug 15-17 at HOPE (hope.net <http://hope.net/?fbclid=IwZXh0bgNhZW0CMTAAYnJpZBExMFdyWUcwTTFHMUkwOHRqNwEeW…>) in Jamaica, Queens at St. John's University. Please stop by if you are in the area! List of artifacts on display: Lawrence Livermore (in a briefcase), 8080 processor. Heathkit trainer ET 3400. TTL Trainer Devry Trainer 555 Timer HP 5036-A TRS-80 Model III or IV Commodore PET IBM P-70 - Luggage IBM Portable - 5140 Pong! Atari 5200 Bally Astrocade Fairchild Channel F We will be promoting our events and local group. Jeff Brace

9 months, 1 week

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24-bin PC clock batteries - who sells?

by Bill Degnan

Looking for the 24-pin PC clock batteries, such as benchmarq p/n: PM346006 Mouser and Digikey is out of stock. Anyone have an adapter or method to make one? Bill

9 months, 1 week

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VCF Montreal Exhibit Registration 2nd Call

by Jeffrey Brace

Register your exhibit with VCF Montreal! There's still spaces left: https://docs.google.com/forms/d/e/1FAIpQLSc4dnGLg9Ubt3gSxNNcOukTIhTNZZK2dQB… VCF Montreal is Jan 24-25, 2026. Jeff Brace

9 months, 2 weeks

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VCF West 2025 Post Event Survey

by Jeffrey Brace

Did you attend VCF West 2025? Please fill out this survey: https://bit.ly/vcfw2025post The show was a great success with record attendance! Jeff Brace

9 months, 2 weeks

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Anyone used a M5C6847 in place of a MC6847?

by Jim Brain

I have a tube of them here, but they won't do anything in any VDG-based system here. Wondering if it's just broken parts (I have no record of buying them, so must have been someone gifting them to me) or there's something I am missing: http://matthieu.benoit.free.fr/cross/data_sheets/M5C6847P-1.pdf -- Jim Brain brain(a)jbrain.com www.jbrain.com

9 months, 3 weeks

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Me again! RSX-11M manual set

by Peter Ekstrom

Ok, it's me again with another RSX-11M question. I have a nearly complete set in PDF form for 4.2. But I am running 4.8. Is 4.2 close enough or does anyone have a set for 4.8 or maybe even 4.6? In searching around on the 'net I have found a release notes doc for 4.8 but that's it. Thanks! - Peter

9 months, 3 weeks

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Re: Chuck Guzis -- Equipment and Archive

by Chuck Guzis

On 7/31/25 16:06, Wayne S wrote: > Michael, Chuck was knowyo a lot of us on the Classic Computer Discord. > Everyone was wondering what was going to happen with his collection. > Glad that you’re willing to oversee the disposition of it all. > > Join the discord snd put your post in maybe general channel. > You’ll get a lot of suggestions and probably buyers. > > Here the invite. > 6e39fdc07ab9ac7cfcf7636761aff7f7.jpg > Join the ClassicCMP Discord Server! <https://discord.gg/tKedmSze> > discord.gg <https://discord.gg/tKedmSze> > > <https://discord.gg/tKedmSze> > Thanks, Wayne. I'll do that.

9 months, 3 weeks

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Re: Chuck Guzis -- Equipment and Archive

by Gary Clark

Chuck was also highly active at the Vintage Computer Federation and there are lots of people on this forum who should be able to help or advise. Best wishes to you and his family. From the small amount of contact I had through the forum, he was a special person. https://forum.vcfed.org/index.php?threads/sad-news-chuck-g.1253843/page-4#po st-1459242

9 months, 3 weeks

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Re: Q about DS3881, N8881 DEC8881..

by Martin Bishop

How available, as NoS rather than pulls, are K559IP1 and its chums 2 & 3 ? Martin -----Original Message----- From: Holm Tiffe [mailto:holm@freibergnet.de] Sent: 01 August 2025 10:45 To: Martin Bishop <mjd.bishop(a)emeritus-solutions.com> Subject: Re: [cctalk] Q about DS3881, N8881 DEC8881.. Martin Bishop wrote: > The 8881 data sheet you reference is identical to the one I found last night, quicker to search than rummage. > ok. > The closest it comes to an output drive specification is in the test conditions for the "0" output voltage. The 17 ma current with 5v supply and 0v4 Vol limit suggests a 270R test load. This is interestingly different from the Qbus use case of 178/383 termination; the Thevinin equivalent being 120R at 3v4 - equivalent to ~25 mA to pull down to 0v4. And, ~22 mA to pull down to 0v8 - the Lo voltage you require, 0v4 being what you would like. Yes, I've read that. > > I am extremely sceptical that bus currents of 70/80 mA are likely, to get 70 mA you need a Thevinin R of ~40R ie three terminators in parallel (61 / 131); many years ago, I could not get two backplane systems to do reliable DMA - never mind three ... However, its in the spec so everyone wants one ... Similarly, getting down to 0v4 with a realistic NPN is a joke, under 0v8 yes but with a Q-bus as load my expectation is only a bit below 0v6. ..german saying "you are heavy on the wood way! (Du bist schwer auf dem Holzweg..yes, I know english for runnaways (englisch für Fortgeschrittene = nonsense)) Thy don't specify bus currents with 70mA, they specify the maximal Output low current that the device could handle ..which has almost nothing todo with the current in the use case Unibus or Qbus. > > If you can obtain K559IP1 I suggest you test them on the bench, they could well be usable. But, yes, the well of old parts is drying out. And, IMHO, some of the requirements in the specs are more what DEC would have liked rather than what they could source. I already have some on stock and.. I own an russian 11/03 equivalent Elektronika E60 with M2 CPU .. worked 5 years before now, stored sine then. As far as I remember the K559IP1 is used there on some boards, and The Bus is a QBUS ..but with metric dimensions even on the connectors. If you are interested here are som pics from the boards: https://www.tiffe.de/Robotron/PDP-VAX/E60/ The Interface Board I4vers3 (И4ред3 in the upper left) E60-06.jpg for the russian RX02 has an K559IP1 (К559ИП1) on the bus side, but nmostly used in this machine are K559IP2 and 3 ..8640 and 8641. So there is no need to test those chips, I know they are working. E60-01.jpg and E60-02.jpg are the CPU Board M2. Regards, Holm BTW: why off-list? [DrB] Your 01 0906Z Aug 25 (below) was off list ... > > Best Regards > > Martin > > -----Original Message----- > From: Holm Tiffe [mailto:holm@freibergnet.de] > Sent: 01 August 2025 09:06 > To: Martin Bishop <mjd.bishop(a)emeritus-solutions.com> > Subject: Re: [cctalk] Q about DS3881, N8881 DEC8881.. > > Martin Bishop wrote: > > > https://forum.vcfed.org/index.php?threads/dec-ttl-part-number-equiva > > le nts.79306/ is a collection of rumours about what DEC 8881's > > > > DS3862 was a National Semi trapezoidal (ie slew rate limited driver), whether that makes a DS3881 a National part is a good question (never found it). > > > > DEC documentation on LSI-11 BusDrivers mentions the 8881 as having DEC order code 957, and describes it as a bus driver. The documentation goes on to say that a 8641 is a 8640 (Bus Rx) integrated with a 8881 (Bus driver); followed by pin out (14p classic TTL NAND pin out) and parametrics. I shall try to find a link to the pdf; I have pp55-58 on A4. > > > > The DS3881 might be an urban myth, perpetuated typo / error ? > > That's my tough too.. > Regarding the russian Datasheet the K559IP1 can source 70mA (an other databook shows 80mA here) that's over the spec of an 8881 as far as I know, the "1972_Signetics_SSI_8400_8800_TTL_DTL.pdf page 2-44" has no value for the max output sink current.. > > It seems that this part is modified from the russians but listet as > DEC Standard and used for the same purpose as the 8881, but it has a > modified Pinout too (2 extra free pins, DIP16 instead of DIP14) > > If found a interesting discussion about the western parts here: > > https://forum.vcfed.org/index.php?threads/dec-ttl-part-number-equivale > nts.79306/ > > I'm a former East-german from "behind the iron curtain"..that's why I'm at least kew of the existence of that equivalent parts. I still know of a source of 8640, 8641 equivalents and I've bought the last 7 8T24 equivalents there. This source is now drying out too... > > Regards, > Holm > > > > > Martin > > > > PS off looking for URLs > > > > -----Original Message----- > > From: Holm Tiffe via cctalk [mailto:cctalk@classiccmp.org] > > Sent: 31 July 2025 20:01 > > To: cctalk(a)classiccmp.org > > Cc: Holm Tiffe <holm(a)freibergnet.de> > > Subject: [cctalk] Q about DS3881, N8881 DEC8881.. > > > > The russians build PDP11's and VAXes. They made chips similar to the special DEC chips. For example there is an K559IP2 which is an DS8640, and there is an K559IP1 and they list an DS3881 as equivalent, 4 NAND gates "standard DEC" Bus driver ..hmm. > > > > 1,2-3, 4,5-6 10,11-9 and 13,14-12. ..input,input-output. 16 VCC, 8 > > GND, > > 7,15 free. It is an 16 pin 300mil DIP. > > > > Now I have problems to find a Datasheet for an DS3881 which is NOT an CCFL Inverter from Maxim/Dallas/Analog but I' pretty shure I've seen such beasts already in the past. > > An DEC8881 is sitting next to an DS8640 on a DLV11 I have in my hands..but this is an DIP14 Chip (similar to an 7401 or an 7439). > > > > What the heck could a DS3881 be? > > > > (DEC Bus drivers are getting rare those days, that's the cause that I've bought those russian chips in the past for cheap.. > > > > Regards, > > Holm > > > > -- > > Technik Service u. Handel Tiffe, www.tsht.de, Holm Tiffe, > > Goethestrasse 15, 09569 Oederan, USt-Id: DE253710583 > > info(a)tsht.de Tel +49 37292 709778 Mobil: 0172 8790 741 > > -- > Technik Service u. Handel Tiffe, www.tsht.de, Holm Tiffe, > Goethestrasse 15, 09569 Oederan, USt-Id: DE253710583 > info(a)tsht.de Tel +49 37292 709778 Mobil: 0172 8790 741 -- Technik Service u. Handel Tiffe, www.tsht.de, Holm Tiffe, Goethestrasse 15, 09569 Oederan, USt-Id: DE253710583 info(a)tsht.de Tel +49 37292 709778 Mobil: 0172 8790 741

9 months, 3 weeks

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Re: RSX11M (not PLUS) v4.8 question

by Mark Matlock

Peter, I also had the same problem when using RSX11M instead of M+. Below is a quick Macro-11 program that sends two VT100 escape sequences. The first clears the screen and the second sends the cursor home. It can be easily modified for other terminal types if needed. For command line editing that works with RSX11M, take a look at the MCE command line editor. It is a great DECUS program found on RSX SIG Tape Spring 1989 in [265,1] Best, Mark >TYP CLR.MAC .TITLE Reset VT Terminal .MCALL QIOW$S,EXIT$S .EVEN MSG: .ASCII <33>/[2J/<33>/[H/ LEN = . - MSG .EVEN START: QIOW$S #IO.WVB,#5,#1,,,,<#MSG,#LEN,> EXIT$S .END START >MAC CLR=CLR >TKB TKB>CLR=CLR TKB>/ TKB>TASK=…CLR TKB>// >PIP LB:[1,54]/NV/CO=CLR.TSK >INS $CLR

9 months, 3 weeks

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Q about DS3881, N8881 DEC8881..

by Holm Tiffe

The russians build PDP11's and VAXes. They made chips similar to the special DEC chips. For example there is an K559IP2 which is an DS8640, and there is an K559IP1 and they list an DS3881 as equivalent, 4 NAND gates "standard DEC" Bus driver ..hmm. 1,2-3, 4,5-6 10,11-9 and 13,14-12. ..input,input-output. 16 VCC, 8 GND, 7,15 free. It is an 16 pin 300mil DIP. Now I have problems to find a Datasheet for an DS3881 which is NOT an CCFL Inverter from Maxim/Dallas/Analog but I' pretty shure I've seen such beasts already in the past. An DEC8881 is sitting next to an DS8640 on a DLV11 I have in my hands..but this is an DIP14 Chip (similar to an 7401 or an 7439). What the heck could a DS3881 be? (DEC Bus drivers are getting rare those days, that's the cause that I've bought those russian chips in the past for cheap.. Regards, Holm -- Technik Service u. Handel Tiffe, www.tsht.de, Holm Tiffe, Goethestrasse 15, 09569 Oederan, USt-Id: DE253710583 info(a)tsht.de Tel +49 37292 709778 Mobil: 0172 8790 741

9 months, 3 weeks

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Ferroresonant transformer mystery

by Tom Hunter

Recently I got a nice and complete PDP-8/s from the US. The power supply uses a ferroresonant transformer which in addition to the standard primary and secondary windings has a separate 2.3H winding connected in series to a 2uF 660VAC capacitor forming a resonant "tank" circuit. The transformer's secondary side and the resonant circuit are operated in saturation. There is a magnetic shunt to prevent the primary side going into saturation as well. It accepts a wide input voltage range, but is very sensitive to the input frequency of 60Hz. This is quite a nice if not elegant design for the period in question, but maybe not the most efficient. As I live in Australia I get 240VAC and 50Hz as opposed to the US 115VAC and 60Hz. I can easily convert our 240VAC to 115VAC with a step-down transformer, but cannot easily supply 115VAC at 60Hz. So I was considering using a step-down transformer to get the 115VAC, but modify the resonant "tank circuit" for 50Hz. Unfortunately there is some magic I don't understand. The resonant frequency of a LC circuit with L=2.3H and C=2uF is about 75Hz not the expected 60Hz. Otherwise I could just solve the standard LC resonant circuit formula for C and plug in 50Hz and 2.3H to get the required C. Obviously ferroresonant transformers are more complex than this former software engineer can grasp. Could any experienced EE with relevant transformer knowledge please chime in and help me understand how to redimension the tank circuit to use 50Hz instead of the original 60Hz input. Obviously I could replace the entire power supply with two modern switch mode supplies to create the two rails, but it would be really nice to keep the original supply and just reversibly adapt it for 50Hz. Thanks and best regards Tom

9 months, 3 weeks

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RSX11M (not PLUS) v4.8 question

by Peter Ekstrom

So, I may just be spoiled from using RSX11M-PLUS and now expect too much from the RSX11M OS. But it seems to me the CLS command would be a nice-to-have, but I am not able to find anything about it. So did that not exist for RSX11M? How does one clear the screen in that environment? -Peter

9 months, 3 weeks

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RP2350 5V Input Tollerant Pins

by Martin Bishop

https://www.raspberrypi.com/products/rp2350/ From postings, I know that folks use the RP2350 for interfacing; the trade press has been shipping news of RP's rev A4 datasheet in volume. The datasheet should tell all. However, the 5V tollerance of the "IO" pins is significant for its simplification of TTL interfacing; the maximum supply and output voltage remains 3v3. See section 14.8.2 (p 1335) et seq - NB the FT indication. Martin

9 months, 3 weeks

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rsts.org -- contact and info for them

by Jay Jaeger

I tried to contact rsts.org using their web site form, but it threw a server error when I tried. I have two pieces of info for them, if they hang out here: 1) The files at http://www.rsts.org/autoindex.php?dir=distros/RSTS_tapes/V_10.0/ and http://www.rsts.org/autoindex.php?dir=distros/RSTS_tapes/V_10.1/ cannot be downloaded: access Forbidden error. 2) I have a product code for the RSTS 10.0 distribution tape (they say "Unknown DEC Product Code" on the index page.) The code on the actual tape is BB-P016P-BC RSTS/E V10.0 INSTALL 16MT9 (Unfortunately, my tape has not yet responded to my attempts to read it - I think the signal that ought to tell the drive it is 1600 BPI PE isn't being recognized by my HP SCSI tape drive - it thinks the tape is 800BPI, but it works OK with other 1600BPI tapes.) JRJ

9 months, 3 weeks

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HP900/735 Ram Modules

by hupfadekroua

Hi all, I‘m looking for Ram modules for my HP9000/735 system. Best Andreas

9 months, 3 weeks

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Re: Wanted: IBM 5324 Monitor

by Jaume López Martin

Hello, I am a collector of old computers and a fellow owner of Datamaster computers. I have seen your CCMP post about wanting to have image output from your 5324. I imagine this computer hasn't been serviced. If you want I could help you to solve both issues. If you still have the computer and want to do something with it, we would first need to diagnose and repair it if necessary. I would guide through the entire process of troubleshooting. After the service, I would instruct you how to get video output through HDMI. Regards, Jaume

9 months, 3 weeks

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IBM SMS cards

by Henk Stegeman

Hi all, I just spotted an auction on eBay for 40 IBM SMS cards. It sold for over $2,000 (!) Does anyone know if this reflects collector value or the value of the gold content? Also, what’s the current value of a set of SMS cold contacts? Thanks, Henk www.ibmsystem3.nl

9 months, 3 weeks

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Scada computers and remote terminal units

by Devin

Greetings, Been a long while since i have posted in on here. I usually discuss my pdp 11 and vax systems. I have decided to pivot my career to scada syatems. The company i am with has some interesting stuff that goes pretty far back. Our custom in house tech is a plc pump controller with a radio connection for data logging and control. Pretty cool, 8051 based, with a version of basic in rom that has scada functions added. The backend servers are just linux systems, although in a modular backplane for easy replacement. I have not read much about this tech outside of what we have in house. Are there other historic scada system computers or technologies that are similar, easily found on ebay for example? Ive seen some mention of old allen bradley stuff, but not much notes on how it would be used remotely in the field, as a remote terminal unit. Any suggestions are appriciated, trying to read more into scada tech outside of my company's tech. Thanks, Devin D.

9 months, 4 weeks

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Re: Scada computers and remote terminal units

by Mark Moulding

Honeywell made a large number of these systems, which were in use in many industries (oil refining, manufacturing of all types, water utility distribution, etc.). They were quite expensive, and PLC manufacturers have made great inroads into that market in the past couple of decades. As a result, some of that equipment is showing up in the surplus market. I found a Honeywell "Orion" console desk being disposed of that I would have loved to take, except that it was truly massive (it must have weighed nearly a thousand pounds!). It was electrically height adjustable (with memory), had mounts for two very large monitors, integrated lighting, cable management, and rack spaces for physical buttons and lights. Actually, a lot of their equipment is pretty massive, especially when compared to current-day PLCs. ~~ Mark Moulding

10 months

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Sad news re: Chuck Guzis

by John

There's been discussion of this on the VCFed forum, but it doesn't look like anybody's brought it up here yet. Per Mike Brutman, list member Chuck Guzis a.k.a. Chuck(G) passed away recently. He was highly knowledgeable, a full-bore storage expert, and an all-around even-keeled decent sort, and will be missed.

10 months

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NeXT Cubes Available

by Bill Degnan

(forgive the dual post with Midatlantic Retro if you're in both groups....) Hello I have been in my spare time messing around with NeXT hardware and I have built three extra working NeXT cube systems (mouse keyboard, computer, display) that I would be willing to let go for less than Ebay prices (look on Ebay for sold status complete systems). Two of them have SCSI2SD hard drives and I have one that still has a working original drive. I don't have any optical disks available, but the optical drives come with the system, untested. There are always caveats to define "works", but basically these are working computer systems that could be connected to a network and they come with a basic Next OS installed. I don't want to ship these if possible. So if you're willing to pick up the system (Landenberg, PA), you can try before you buy and pick the one you want at a discount to Ebay price. Contact me through kennettclassic.com/contact.cfm with your offer/timeline. FIrst come first served. Shipping is available if you want to pay a shipping charge, plus postage. I have shipping boxes. I am going to VCFMW this year, but I am flying there and won't be able to bring them. If you want the cube system delivered to VCFMW, you'd have to find someone to deliver it for you, or have it shipped. I am willing to deliver a system a reasonable distance from the Phila/Baltimore area. Cash, CC, Paypal, check accepted. Bill Degnan 484 732 7041 kennettclassic.com

10 months

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VCF West 2025 Hotel Block Still Available!

by Jeffrey Brace

What do you mean you haven't booked your hotel room for VCF West 2025? The hotel block is filling up fast! Check out this link for more info: https://vcfed.org/2025/07/22/vcf-west-2025-hotel-still-available/

10 months

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AMIGA/040th – Step Behind the Curtain @ VCF West 2025 @ CHM - Aug 1 &2

by Jeffrey Brace

Travel back to the legendary 1984 CES debut of the Amiga and witness exclusive prototype demos in a fully immersive recreation. Rare Amiga Corp and Commodore artifacts will be on display, along with special presentations celebrating key milestones—including the launch of the Amiga 500 and its pop culture impact, featuring a recreation of the Spielberg-inspired “bedroom computer” scene. Explore the revolutionary NewTek Video Toaster and Flyer in a 1990s editing room, and experience rare Amiga coin-op arcade machines in action. Dive into the vibrant world of European Amiga demos and explore a full lineup of Amiga systems—from original classics to modern enhancements using Raspberry Pi, AmiKit, Vampire, MorphOS, AROS, and AmigaOS 4. Browse Tony’s Amiga Emporium for collectible systems, and check out the latest hardware from A-Eon and AmigaKit, including the A1222, A600GS, and A1200NG. Don’t miss this celebration of innovation and legacy! Show info: https://vcfed.org/events/vintage-computer-festival-west/ Tickets: https://vcfed.org/events/vintage-computer-festival-west/vcf-west-tickets/ Jeff Brace

10 months

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SyQuest disk anyone?

by Peter Ekstrom

I am looking for a 15MB SQ300 disk cartridge in working condition. Anyone have one they wouldn't mind parting with? - Peter

10 months

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PDP-11/93 memory question

by Bill Gunshannon

I have an 11/93 with 2MB of memory onboard. I would like to kick it up to 4MB. I got some memory a while ago that was supposed to be PMI for it but it turned out to be UNIBUS and thus no help. I have some old fashioned QBUS memory module floating around. Will these work to add the missing 2MB or can the 11/93 only use PMI? Would be nice to wake this old box up again. I have this cool Decromancer just crying for somewhere to run. bill

10 months

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VCF West 2025 Consignment, Aug 1 & 2, Mountain View, CA

by Jeffrey Brace

Get your items into the system! Print your labels ahead of time! Buy and sell treasures. More info here: https://vcfed.org/events/vintage-computer-festival-west/vcf-west-consignmen… Jeff Brace

10 months, 1 week

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Endeco Cartridge Reader

by Steve Lewis

Is anyone familiar with the Type 1138SSM Cartridge Reader by Endeco, Inc (of Marion, MA) ? I recently got one, it appears to have an RS-232 interface at the back (and a power cable). I believe it is from around 1989. The cartridge slot has a connector that looks like something an NES might have. That is, it is not a tape, but it is much larger than CompactFlash. If anyone is familiar with these, I'm trying to find some cartridges and any kind of manual on how to interface with the thing. Thanks! Steve

10 months, 1 week

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RK06/7 manual?

by Mark Kahrs

LSSM is looking for a copy of the RK06/07 Technical Description Manual, EK-RK067-TD-001. If anyone can give or loan it to us, we can scan it as well for public distribution. Thanks.

10 months, 1 week

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Selling a Wang calculator

by pontus

Hi I know this isn't exactly the right group for this. But I have a fairly uncommon Wang calculator for sale and am not sure where to post about it. I've tried "Vintage Calculators Buy & Sell" on facebook without much luck. I see there is some calculator activity on discord, so I'll post about it there but I'd be happy for suggestion of other venues before I go the E-bay route. Below is the blurb I posted on facebook and here is a link to photos of the thing: https://drive.google.com/drive/folders/1gNdVSsNDxDL1Ukjh13-2ElJXRiWKQ5rx?us… FOR SALE: a Wang 362E electronic calculator in good condition, some scuff marks and light scratches but the inside is clean and looks to be complete. It comes with the 370K programming keyboard with nixie tube display in original dust cover, two card readers model 371 (with feet), four manuals in English and one in Swedish with handwritten notes. Also included is an IBM port-a-punch in box. I have decided not to test it in order to avoid causing any damage from improper handling or due to problems with ageing hardware. Located in Uppsala, Sweden. I will ship internationally but please allow some time for me to package it properly and figure out the best shipping options. I have shipped heavy computers and even CRTs with success, so I’m not without experience. Give me an offer :)

10 months, 1 week

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9-Track Tape Extraction

by lukeparkerson1＠gmail.com

Hi all, I recently got my hands on what I believe is a 9-track tape, dated 1986, which has some old survey data stored on it from a university research project several decades ago. I'm hoping to be able to extract the information from the tape and convert it to a more modern data file accessible to the public, but I don't know very much about these tapes nor do I have 9-track tape equipment. I'm wondering if anyone who is more familiar with this technology can tell me it's even still possible to extract this data, and if so, is there's anyone here who can try and run the tape, or knows someone with a working 9-track tape drive? The frame is not in the best shape, but the tape is hopefully fine. Here's a photo: https://drive.google.com/file/d/1PrdBnIWUO4-317ZSwqvY-TD6dHr2CxC8/view?usp=… Thanks, Luke

10 months, 1 week

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Re: Lee Felsenstein at VCF West August 1 at 4:30PM

by John Foust

At 04:22 PM 7/10/2025, you wrote: >Lee Felsenstein at VCF West Friday, August 1 at 4:30PM. >He will talk about the 50th Anniversary of The Homebrew Computer Club. Here's the line-up: https://vcfed.org/events/vintage-computer-festival-west/vcf-west-speakers/v… Not just Lee... but also Bob Marsh of Processor Tech, and Harry Garland of Cromenco, and Dan Sokol of Apple... And then for the Amiga 40th events, Dale, RJ, Trevor, Perry, Willie, Marco, Bill, Aaron, Brad, and me, too! And Sellam is there! - John

10 months, 1 week

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Comstar System 4 Intel 4004 based Industrial Computer Documentation

by Christian Liendo

I was able to obtain a number of documents that pertain to the Comstar System 4. I spoke about this computer in the past but I have scanned some documentation that should help explain this unique computer People who have been interested in the Intel 4004 might find this interesting The Comstar System 4 Reference Manual is rather detailed on the computer itself and it's applications This is the Complete Comstar System 4 Reference Manual https://archive.org/details/comstar-system-4-reference-manual_202507 Warner & Swasey Reference Manual https://archive.org/details/warner-swasey-comstar-star-system-reference Comstar System 4 Programming Manual https://archive.org/details/comstar-system-4-programming-manual Comstar System 4 Tester Manual https://archive.org/details/wscomstar-system-4-test-manual Comstar System 4 CPU Module Schematic https://archive.org/details/comstar-system-4-cpumodule Comstar System 4 Serial Communications Schematic https://archive.org/details/comstar-system-4-serial-communications Comstar Star System 4 RAM Module Schematic https://archive.org/details/comstar-star-system-4-rammodversion Comstar Star System 4 HTL I/O DATA Module Schematic https://archive.org/details/comstar-star-system-4-iodatamodule Comstar Star System 4 PROM Module Schematic https://archive.org/details/comstar-star-system-4-prommodule Comstar Star System 4 PROM 1k 2k Module Schematic https://archive.org/details/comstar-star-system-4-prom-1k-2k-module Warner & Swasey Comstar System 4 Process Control Language https://archive.org/details/wscomstar-system-4-pclref-manual Warner & Swasey Computer Division Comstar System 4 Machine Language / Assembly Language Reference Manual https://archive.org/details/wscomstar-system-4-assembly-language Comstar System 4 Program Analyzer Reference Manual https://archive.org/details/comstar-system-4-reference-manual Computer History Museum's Archive of the Manual https://www.computerhistory.org/collections/catalog/102686568 Comstar Computer Systems Process Control Language Data Sheet https://archive.org/details/comstar-star-pclcompiler-data-sheet

10 months, 1 week

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Video: Introduction to Chiptunes by Inversephase @ VCF East2025

by Jeffrey Brace

Introduction to Chiptunes by @inversephase video released today (7/14/2025): https://youtu.be/i0v712l2RWE Enjoy! Jeff Brace

10 months, 1 week

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Interact One Message Center

by Steve Lewis

Hey all, I'm trying to track down a manual or instructions for the Message Center program on the Interact One (from 1978). I've run this in the MAME emulator, and it seems the program has a "partial" BASIC-like interpreter. You can do line numbers, like 10 HELLO 20 WORLD Then issue the command SCROLL, and it will start scrolling text in the numeric sequence they were specified. Then you can also do commands like FLASH, BUZZ, BEEP in its equivalent of "immediate mode" -but I don't know yet how to specify these commands in the numeric program. And in the emulator, I can't yet parse the commands PLOT, SOUND, SIZE - these "message center" program specific commands,not BASIC (BASIC on this system is loaded from tape). Anyway, a manual on a program for the Interact One called "Message Center" is what I'm trying to track down. Thanks, Steve

10 months, 2 weeks

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IBM System/23 Datamaster 5324 Towers and IBM 5247 HDD Tower Available

by Ali

Hello All, A long time ago I acquired a System/23 desktop unit and eventually a number of the tower units including the HDD tower unit. The plan was to setup a System/23 Muli-User system with multiple terminals connected together. Well, like many great plans real life got in the way and the units have been sitting in storage for a few years. I have accepted that this is one of the projects I will never get to and it is time to pass them on to someone else who can enjoy them. The systems are in SoCal (Upland, CA to be more exact). More info can be found at the following links: https://forum.vcfed.org/index.php?threads/ibm-system-23-datamaster-5324-towe r-model-of-the-5322-with-original-clicky-keyboard.1253651/ https://forum.vcfed.org/index.php?threads/ibm-system-23-datamaster-5324-towe r-model-of-the-5322-with-one-floppy-drive.1253652/ https://forum.vcfed.org/index.php?threads/ibm-system-23-datamaster-5322-or-5 324-hdd-tower-model-5247.1253653/ I hate to part/scrap them as the towers rarely show up so I am hoping someone local would be interested in them. Feel free to email me directly or reach out through VCF. Thanks -Ali

10 months, 2 weeks

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Vax boxes, parts

by Paul Anderson

I did some digging and found one 3000-400 with no lid( It could be here somewhere) and I'll have to move it to look it over to see what's there. I had 6 or so 3000s and I guess I sold them, but more digging to do. MV3100 M76 MV3100s I can't get to the model number 4000-60 5000-25 5000-125 5000-133 5000-200 I had to pull some boards and made a small list. M7621 M7622 M7624 M7625 M7626 54-21149 KN15 If you need a board I have not listed, please email me off list. If I haven't replied, bug me. I did not list qtys- some items are more than one. Thanks, Paul

10 months, 2 weeks

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Q-bus, PDP8, VAX items

by Paul Anderson

As many of you know I have been trying to finish organizing my Unibus parts and finish building several systems for years. Other than time and my health I don't have enough space. I would like to sell, at reasonable prices, all of my q-bus parts which include 400 - 500 boards, about a dozen boxes, and a lot of spare parts. I have BA11-M, BA11-N, BA11-S and a few BA23 boxes left. If you have an original 11/03, I have a dozen or so H780 power supplies, which are very hard to find. They are also used in the Vax 11/780 front end, the RKV11-D and possibly a few other items. I can test them if I have time, but that might take awhile. I'm also taking offers on some of my 8-E and all of my 8-A items. I will entertain offers on the VT14 and all of the PDP 14 industrial controller parts. I have a few Vax 3000, 5000, and a few others along with parts including memory. Those of you who have been here know I have a ton of DEC and DEC-compatible parts, but no one has seen everything. I have brand new disk heads, tape drive heads, alignment packs, and literally tons more. I went through over 50 backplanes a few weeks ago looking for a few specific ones. Some Unibus items are also going. Probable some 11/05s, 11/34s, 11/83 and/or 84s and a lot of options and boards. So if you need or are thinking about DEC items, feel free to send me a wish list off list. I prefer phone calls and will send my number upon request. I was never great at typing and I'm getting worse. Oh- I also trade for US and foreign coins and currency. Thank, Paul

10 months, 2 weeks

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More equipment available in Upland, CA

by Ali

I also have the following available for whoever is interested: Sony StorStation AIT Library LIB-162 https://forum.vcfed.org/index.php?threads/sony-storstation-ait-library-lib-1 62.1253656/ HP SureStore SC10 https://forum.vcfed.org/index.php?threads/hp-surestore-sc10.1253657/ HP Impact Line Printer 2563C (this is one nice printer and if I had the room I would keep it but alas....) https://forum.vcfed.org/index.php?threads/hp-impact-line-printer-2563c.12536 54/ -Ali

10 months, 2 weeks

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Lee Felsenstein at VCF West August 1 at 4:30PM

by Jeffrey Brace

Lee Felsenstein at VCF West Friday, August 1 at 4:30PM. He will talk about the 50th Anniversary of The Homebrew Computer Club. Get tickets here: https://connect.computerhistory.org/.../1ffceb98-f556... <https://connect.computerhistory.org/events/1ffceb98-f556-df49-f011-42475680…> Info here: https://vcfed.org/events/vintage-computer-festival-west/ <https://vcfed.org/events/vintage-computer-festival-west/?fbclid=IwZXh0bgNhZ…> Jeff Brace

10 months, 2 weeks

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Re: Burroughs backplane story, was Re: Another 780 backplane story

by Freek Heite

Ah, thank you Paul, for sharing this story. Postings like this make cctalk worth every penny, IMO! Regards, Freek. -----Original Message----- Date: Tue, 08 Jul 2025 21:30:36 -0000 From: paul.kimpel(a)digm.com Subject: [cctalk] Burroughs backplane story, was Re: Another 780 backplane story To: cctalk(a)classiccmp.org Message-ID: <175201023609.1228.2550589532797629102(a)classiccmp.org> Content-Type: text/plain; charset="utf-8" In early 1971, I started working as an on-site software tech on a rather large (for the time), dual-processor Burroughs B6500. It was early days for that system, and we had a lot of problems with it in the field. We got those ironed out pretty well and eventually got the system up to an acceptable level of operation. <<< snip>>> We finally deduced that the problem had been present since the system left the factory floor. The original I/O software had been so poor that the system was seldom (if ever) able to initiate more than one I/O to disk at a time, but the new version we had recently installed was really good at initiating multiple I/Os. Mux 1 had a lower selection priority than Mux 0, so under the old software it was seldom selected, and perhaps never so for tag transfer I/Os, which are relatively rare. The new software allowed the system to get busy enough that Mux 1 started to be used a lot more often, and eventually it got busy enough that a paging I/O for that master PCW array got scheduled to Mux 1, and the system just didn't survive for very long after that.

10 months, 2 weeks

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Burroughs backplane story, was Re: Another 780 backplane story

by paul.kimpel＠digm.com

In early 1971, I started working as an on-site software tech on a rather large (for the time), dual-processor Burroughs B6500. It was early days for that system, and we had a lot of problems with it in the field. We got those ironed out pretty well and eventually got the system up to an acceptable level of operation. About a year later, a major upgrade to the MCP (the OS) was released. A major component of that release was a completely rewritten I/O subsystem with much higher reliability and much, much better performance, especially in "Logical I/O," the interface between user programs and the memory buffers and physical I/O mechanism. Soon after installing this release, we started to get fatal system crashes in Logical I/O. Describing what was happening requires a little background on the system architecture. The B6500, like its predecessor the B5500, is known as an ALGOL-oriented stack machine, but it is less well-known as a type of capability system. To support that, it used a segmented memory model and tagged memory. Each word had an extra three bits, not accessible to user programs, that identified the type of data in a word. For example, tag 0 was ordinary data, tag 2 indicated a double-precision word, tag 5 was a data descriptor through which data segments were addressed, and tag 7 was a Program Control Word (PCW) that effectively addressed a location in an object-code segment. It was used primarily as a procedure (subroutine) entry-point address. In reading the dumps from the crashes and the MCP source code, we started to learn how the new Logical I/O mechanism worked. It cleverly used the stack addressing of the system to implement a very object-oriented interface. The "methods" of this interface were small procedures that were customized to handle very specific cases of record handling -- random vs. sequential I/O, blocked vs. unblocked I/O, translation or no translation, etc. There were scores of these methods. The idea was do a little as possible for each user request and to avoid making as many decisions as possible and to optimize the buffer handling in each case. There were about a half-dozen different types of user requests, and the methods for those were accessed through a branch table in the FIB (control block) for each open file. That branch table contained PCWs for the appropriate methods needed by that file. The table was set up during file open, but could be changed as the nature of the user program's requests changed, e.g., from sequential to random access. We discovered that the crash was caused by some PCWs in the file-level branch tables having tags of 5 instead of tags of 7. Attempting to call a procedure using a tag-5 word was a no-no that was trapped by the hardware, hence the fatal dump. Then we discovered that the branch tables were loaded from a master array of PCWs for all of the possible methods, and when we looked at that array in the dump, ALL of the PCWs in the array had tags of 5! We know that array initially had to have had words with tags of 7, because the system had run for quite a while before crashing, so how could all of the words in the array suddenly have changed to tags of 5? There wasn't any straightforward way to do that in software. That master array was loaded from from the OS image on disk at the initial boot, but then we found out the array was overlayable -- it could be paged out and back in by the virtual memory mechanism. So we began to suspect there was an issue with I/O. Normally, a disk read stored words in memory with a constant tag of 0, but there was a special I/O mode, termed "tag transfer," that would read and write the tag bits along with the regular data bits. Fortunately, the other tech on the site had worked in the MCP group for a while and knew the I/O hardware pretty well, so he started writing some standalone programs to exercise the hardware in specific ways. This system had two I/O Multiplexors (multi-channel DMA units) numbered 0 and 1, and the disk drives were dual-ported so that either Mux could address any of them. My colleague's programs tried doing I/Os with various combinations of Mux and channel assignments. And as you might expect by now, he discovered that doing a tag transfer read through Mux 1 always dropped the middle tag bit. We turned that finding over to the on-site Field Engineers, who pulled out their schematics and started tracing signals. It took several hours, but eventually they discovered not a loose wire, but that Mux 1 was completely missing a wire. Of course, it was the wire that carried the middle bit of the tag during tag transfer. We finally deduced that the problem had been present since the system left the factory floor. The original I/O software had been so poor that the system was seldom (if ever) able to initiate more than one I/O to disk at a time, but the new version we had recently installed was really good at initiating multiple I/Os. Mux 1 had a lower selection priority than Mux 0, so under the old software it was seldom selected, and perhaps never so for tag transfer I/Os, which are relatively rare. The new software allowed the system to get busy enough that Mux 1 started to be used a lot more often, and eventually it got busy enough that a paging I/O for that master PCW array got scheduled to Mux 1, and the system just didn't survive for very long after that.

10 months, 2 weeks

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Update on Qbus backplanes

by Paul Anderson

For those of you who wanted the Qbus backplanes here is the list. I've been moving things around and found them while looking for something else. Please contact me off list with any questions. H9270 4 x 4 used in the BA11-M for the original PDP11/03 H9270 with card cage complete 11/03 box, boards available H9276-B H9276-B with card cage H9278-A 2x12 micro backplane with card cage BA123-A Sygma 4x8 with card cage Heath

10 months, 2 weeks

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Re: Another 780 backplane story

by Marvin Johnston

While not on a 780 back plane, about 50 years ago, I was basically in charge of some 26 PDP16M computers. Periodically, one of the chips would be found with the top blown off. At some point, I pulled the computer and examined the backplane filled with wirewrap wires. The solution turned out to be fairly simple... a -15V bus was about .001" near one of the wirewrap posts. A slight moving of that bus away from the wirewrap post solved that problem. I have to assume it was a temperature related problem since increasing that spacing solved the problem. Unrelated to the computer problem, another source of angst was intermittently one of those computers would crash. That one took probably a year to find... one of the interface M series pullup cards had a pulldown card installed in its place. I should mention all the above took place on a newly install system. Marvin

10 months, 2 weeks

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IBM backplane story was Re: Another 780 backplane story

by trp

I worked part time at a computer center for a large bank while getting my undergraduate degree. The center was getting one of the first IBM 3081 machines to replace the existing 3033 MP. Because of the helium filled modules, getting the machine from the climate controlled truck to the center, which was on the 7th floor of the bank building was crazy; the move had to be accomplished in 30 minutes. As a dry run, IBM supplied a size and weight dummy 3081 in advance to make sure the delivery went smoothly. As you might imagine, the install and switch over to the 3081 was high profile. The VP in charge of the center was under pressure to get it done on schedule. The delivery and initial install went according to plan. The data was migrated to the new disks and the various application software was run through its paces. Unfortunately, the 3081 would occasionally throw a power fault. The local FE’s could not determine the cause, so after a week or so second level support was called in. They could not figure it out, so IBM brought in Ivan (I think that was his name). You know when you get the hot shot from IBM when he arrives in bib overalls and tennis shoes, not a suit and 5 pound wingtips. After the second day, Ivan got tired of the stream of managers asking him when the 3081 would be available, so he went down the the main bank floor and grabbed the thing (I cannot remember the proper name) banks used to use to create teller lines (posts and satin “ropes”), and formed a cordoned area around the 3081’s console. Note that each computer console had a telephone (1 for each 3033 and one for the new 3081) for communicating with the computer operator. On the third day, the VP bypassed the cordon and asked Ivan when the 3081 would be operational and Ivan replied he was’t sure. The VP said he had already told the president it would be up by the end of the day, and Ivan handed the VP the phone on the console and said, and I quote, “Call someone who cares”. I kid you not, I still remember verbatim. Early afternoon of the third day, Ivan asked the Lead FE to get a torch. There was an awesome hardware store about 6 blocks away, so in about 20 minutes the torch was delivered. The power bus on the 3081 had enormous cables composed stranded 4-6 large gauge wires that were soldered to large metal plates. Ivan had determined that the wires were improperly soldered and used the torch to resolder them. You can imagine the horror on the faces of the staff as Ivan opened the power bay, lit the torch, and started melting the solder. And it worked! No more power faults. — Todd

10 months, 2 weeks

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PDP8-A parts

by Paul Anderson

As requested, here is a partial list of the 8-A parts available. I have a few more to go through, but most are on here except for possibly a 128K memory board. I have some omnibus boards, M8357 RX8e, LA180, LQP, etc, and will try to make a list next week. If you need something not on here, please ask. I have at least one of each of the following, and more than one of some. G8016 G8018 H9194 12 slot 8-A backplane limited front panel programmers panel MM8-AA MM8-AB M8315 M8316 M8317 M8319 M8416 M8417 Also some non dec: REMEX PC8E core memory A complete 8-A mounted in the desk with RX02s. It's currently in the back of a 20 or 25 foot rental locker, but I hope to get it out this summer. It came with a LA35 and maybe a VT52.

10 months, 2 weeks

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VAX 86x0 schematics

by P Gebhardt

Dear list members, I was wondering if anybody is aware of VAX 86x0 schematics having survived the product life cycle within DEC? I searched the web extensively but could not find any hints on this. It seems that DEC never published such details as schematics for the successor of the VAX 11/78x systems, not even on microfiche, maybe due to the macrocell array implementation (just a guess). All I could find is that there were illustrated parts list on microfiche. However, maybe Hewlett Packard handed DEC-internal documents over to a museum such as the CHM? Or a former designer still have schematics in their archives? Any pointers would be greatly appreciated! Best regards, Pierre ----------------------------------------------------------------------------- http://www.digitalheritage.de

10 months, 2 weeks

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Another 780 backplane story

by Mark Kahrs

Jon Elson's take hits home. A 780 was delivered and VMS was running. We installed 4.1BSD and it ran fine until it crashed. Field service insisted we needed a full set of RS-232 wires in our cable. Still crashed (surprise!). Switched to VMS, still crashed after a while. Local field service couldn't find it. The big guns flew in from Maynard. First day: Couldn't find it. Second day: "What, what's that wire doing there? Have a wire-wrap tool?". Removed wire from backplane. Boots, runs. Engineer flies home.

10 months, 2 weeks

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Repair procedures

by Paul Koning

Side tracking slightly from the "VAX 86x0 schematics" discussion into changing field service procedures over the years: I remember some fairly hairy cases in the 1970, when FS engineers had to be way more capable than board swappers. 1. DEC RS64 fixed head disk was behaving badly, making more noise than expected. Machine was not under contract. FS tech took it apart, diagnosed bad bearing. To save the customer (college physics department) a pile of money, he took it to Appleton Electric Motor Co., where they found a suitable bearing, pulled off the bad one, pressed a replacement on. Jim reinstalled the motor into the drive, worked great. 2. Same college, different machine: RF11 drive was showing "clock track failure". Diagnosis: drive is not spinning. Same tech. Jim took the drive apart on a desk in the computer center, noticed a head had crashed and melted, hot-glueing itself to the platter so the motor was blocked. This machine was under warranty, so he ordered a pile of parts: full set of heads, motor, platter, plus tools. Replaced the motor, replaced all the heads and aligned them, replaced the platter, and formatted the timing track. The manual for that formatter was not exactly intellegible... 3. Different university, CDC 6500 mainframe, occasional data corruption in one of the mass memory transfer paths. After lots of test code added to the application (PLATO system), the tech concluded he knew the answer. Opened up one of the cabinets, lifted up a massive bundle of wire to reach a spot where one of those wires was "punched in" to a module connector, and re-punched the pins of that wire. Repeat at the other end of that wire. Run tests, problem fixed. In that machine, there were a dozen or so chassis, with up to 750 or so modules, each with 28 signal pins, most of them interconnected to elsewhere with twisted pair wires terminated in tapered pins that were pressed into place. It was a surprisingly reliable system but we learned it wasn't 100%, and it took quite some skill and perseverance to find which of those tens of thousands of wire connections was the failed one. paul

10 months, 3 weeks

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VCF West 2025 Hotel Block is available!

by Jeffrey Brace

VCF West 2025 Hotel block is available! https://vcfed.org/2025/07/03/vcf-west-2025-official-hotel-available-now/ Take care! Jeff Brace \

10 months, 3 weeks

1
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DEC music board

by pontus

Hi Paul I see that you are clearing out QBUS board. I've been looking for a "DIGITAL Q BUS music board" for a while. It is a board without M-number as it was never sold. It is a simple dual board with two AY-3-8192 chips on. There are pictures available, if you want I can send them to you. I live in Sweden, I hope we can work out shipping if you have the board. Regards, Pontus.

10 months, 3 weeks

2
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DEC items: update II

by Paul Anderson

I was digging through DEC compatible boards for someone and realized I should have posted them. I have over 100 dual, quad, hex and VAX boards from the usual suspects- ABLE, CMD, DIGITAL PATHWAYS, DILOG, EMULEX, MT, PLESSEY, REMEX (paper tape interfaces for 8s and 11s). Included are core memory boards for 8s and 11s.

10 months, 3 weeks

1
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Databook Library to be scrapped

by Charles Dickman

A small data book library at my work is going to be cleaned out soon. It is mostly common stuff from 1995 and older. I don't believe there is anything unique. You can see a some pictures of the shelves here: https://photos.app.goo.gl/jdJnUdRPvzvRzeTp6 I can't sell them and I won't ship them. If you see anything that should be saved I will squirrel it away with the intention of scanning and getting it online someday. -chuck

10 months, 3 weeks

5
5
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The Big Rewrite (American Pie parody)

by Chris Elmquist

Apologies if this is a dupe here but I don't remember seeing it, https://www.youtube.com/watch?v=xCGu5Z_vaps :-) -- Chris Elmquist

10 months, 3 weeks

2
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DEC items: update

by Paul Anderson

Front panels: I have both 8-A, KY11-LA and -LB for 11/04, /34, one each 11/70 RDC remote diag con, corporate (blue/blue), and regular. I think there is an 11/40 with a 11/35 silkscreen. I have to go through the 8-E, F, and Ms. The last dual extender is on hold, one quad is left, a few hex, a comet (730 or 750 I think), and a 780. Also a few 11/04 and 34 in BA11-L, maybe a -K, and a few 11/83s. I think most of these are systems, not just boxes. The printers include LA12, LA34, LA36, and LA120 and parts for most. There are several hundred non-DEC boards, and a lot of core memory. I'm still looking for the rest of the simms. At some point, I'll be cutting the fingers off of boards no one wants. If you are interested in any qbus or unibus boards for chips, let me know. I can bring items to VCFMW to drop off there. There are a lot of people who drive in from different parts of the country who might be willing to work something out for some gas money. Thanks, Paul

10 months, 3 weeks

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Re: Q-bus, PDP8, VAX items

by Alan Frisbie

Paul Anderson <useddec(a)gmail.com> wrote: > If you have an original 11/03, I have a dozen or so H780 power supplies, > which are very hard to find. They are also used in the Vax 11/780 front > end, the RKV11-D and possibly a few other items. Wow, someone who actually knows about the RKV11-D!!! I've had DEC people visit my place, see the RKV11-D, and proclaim that "DEC never made that!". Since you know what it is, can you tell us anything about how it came to be, and why it is so little-known? I bought mine back in 1978 or so from Newman Computer Exchange for my 11/03. I later added the missing wires (and chip) to enable 18-bit addressing when I got an 11/73. I haven't used it since I moved to Oregon six years ago, but it would take just a few hours to remove the RK05 head locks and plug things in, assuming that all the capacitors are still good. It came in handy to prove to the RSX development group that RSX-11M version 2.0 would run on an 11/73. :-) Alan Frisbie

10 months, 4 weeks

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Is there a more modern replacement for paper tape punch/reader

by ben

Now that I have my 18 bit retro computer working, I am thinking of adding classic IO, like paper tape. Sadly I am a few decades too late. Is there anything out there to replace a punch/reader used as 70's i/o? Any good mag tape (cassete tape) replacements? I would love a tiny 9 track mag tape toy sized if they made one, like the wall hanging PDP8's. On wish list, a flex writer or TTY video display replacement, ie overstrike and underline in 2/3 size VT100 case. Ben. https://www.instructables.com/23-Scale-VT100-Terminal-Reproduction/

10 months, 4 weeks

22
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Re: VCF West August 1-2, 2025 - Mountain View, California

by John Foust

At 09:18 PM 3/11/2025, Jeffrey Brace via cctalk wrote: >VCF West is back on August 1 & 2, 2025 at the Computer History Museum in >Mountain View, California. > >We're partnering with the Sacramento Amiga Computer Club and AmiWest to >celebrate the 40th anniversary of the Amiga and other special guests. I'm considering attending this Amiga 40th anniversary celebration. I was invited to speak on a panel on the topic of the experience of early Amiga code development. Who else might attend? - John

10 months, 4 weeks

4
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EPSON 6110 Tape Punch Interface

by Martin Bishop

I have a salvaged Epson 6110 tape punch on the bench, also it's interface card from a Data Dynamics Zip 30. The 6110 is the shiny paper tape punch which was very common, at front left, on TTY etc in the 70's and into the 80's I'm working on reverse engineering the Epson 6110's connector / interface, it's a "centronics" 24 pin. Does anyone have or know of a spec for the Epson interface, or manuals for a system using it. The basics are plain enough 24V power, ground connections, 8b+s, all low side drivers (54SN463's), one output (to a 7414) I presume Ready_n, and another two inputs I guess Enable_n and Advance_n (or maybe Reverse). RevEng should get me there, documentation would ensure no possibility of magic smoke - excluding bad components. Bring up plan is: - apply 28 V and scope "connector" - button up to suitable processor; ie interpose LoSide drivers between processor's LVTTL and the punch VMTiA Martin

10 months, 4 weeks

1
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DEC VT11/VR17, BA350/BA356, "S" box boards

by Paul Anderson

Just a quick note/ update from my earlier post. If you're looking for an option, please send me the board #. Example:A DLV11 can be a M8017, M8027, M8028, or M8043 if my memory is working tonight. My boards are basically in numeric order, and it takes time to convert option # to part # and I don't want to ship anyone the wrong part. I have a few VT11's I will finally sell, along with a (believe it or not, long story...) VR17 which now has screen rot. A few dozen BA350 and BA356 boxes and selection of power supplies and drives. 50 or so "S" box handle boards including M3108, M3116, M3127 DESQA, M3134, M5976 KZQSA, M7493, M7740 KLESI, M8086 LPV11, M8020 DPV11, M7516 DELQA, M7504 DEQNA, M7504, M7554 CPU, Non DEC and more. Also found a pile of DECMUXII , DECMUX300, decservers and that type of stuff. And something everyone needs, SC08s!!! Please excuse any typos or messed up part #s. Thanks, Paul

10 months, 4 weeks

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VCF West 2026 - Speaker List

by Jeffrey Brace

Speaker List VCF West 2025: https://vcfed.org/events/vintage-computer-festival-west/ Show info: https://vcfed.org/events/vintage-computer-festival-west/ Ticket info: https://connect.computerhistory.org/events/1ffceb98-f556-df49-f011-42475680…

10 months, 4 weeks

1
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VCF Montréal 2026 Speaker Registration

by Jeffrey Brace

VCF Montréal 2026 speaker registration is open now! https://forms.gle/iGqhMsfu94YcGoLp6 Show info is here: https://vcfed.org/vcf-montreal/ Les inscriptions pour les conférenciers du VCF Montréal 2026 sont ouvertes ! https://forms.gle/iGqhMsfu94YcGoLp6 Informations sur le salon : https://vcfed.org/vcf-montreal/ Jeff Brace

11 months

1
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Looking for IBM System/3 BASIC book

by Steve Lewis

Per the link below, it mentions a reference manual to IBM's BASIC for the System/3 as part number GC34-0001-1 but that no digital copies are known to exist. https://manx-docs.org/details.php/19,11119 I know at VCF East they've been trying to restore one of these. Not sure if any functional system still exists (especially probably not the Model 6 with CRT and disk drive). Anyway, if anyone happens to have the physical manual described above, I'm just curious if in the first few pages was it publication date? (before or after 1970?) Also - since IBM went out of their way to re-use the BASIC from the System/3, does that imply there was never a variation of BASIC written for the IBM 360/370? (asking because from my understanding, the System/3 was a lot more difficult to program and operate -- and yet someone wrote a BASIC interpreter for it). -Steve

11 months

12
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VCF West 2025 - Exhibit Lineup - Aug. 1 & 2, Mountain View, California

by Jeffrey Brace

Wow! VCF West 2025 Exhibit lineup: https://vcfed.org/events/vintage-computer-festival-west/vcf-west-exhibits/ Show info: https://vcfed.org/events/vintage-computer-festival-west/ Ticket info: https://connect.computerhistory.org/events/1ffceb98-f556-df49-f011-42475680…

11 months

1
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VCF Montréal 2026 Exhibit Registration

by Jeffrey Brace

VCF Montréal 2026 exhibit registration is open now! https://forms.gle/TKrCy7EyBHubRAdu7 Show info is here: https://vcfed.org/vcf-montreal/ Les inscriptions pour l'exposition VCF Montréal 2026 sont ouvertes ! https://forms.gle/TKrCy7EyBHubRAdu7 Informations sur l'exposition : https://vcfed.org/vcf-montreal/

11 months

1
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VCF West 2025 - Tickets - Aug. 1 & 2 at Computer History Museum - Mountain View, California

by Jeffrey Brace

Get your tickets to VCF West 2025 now! https://connect.computerhistory.org/events/1ffceb98-f556-df49-f011-42475680… VCF West takes place August 1 & 2 in Mountain View at the Computer History Museum. More info here: https://vcfed.org/events/vintage-computer-festival-west/

11 months

1
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VCF Montréal 2025 Jan 25-26

by Jeffrey Brace

VCF Montréal is coming Jan 24-25, 2026. Reserve your hotel now! https://vcfed.org/vcf-montreal/vcf-montreal-2026-hotel/ Show updates here: https://vcfed.org/vcf-montreal/ Le VCF Montréal aura lieu les 24 et 25 janvier 2026. Réservez votre hôtel dès maintenant ! https://vcfed.org/vcf-montreal/vcf-montreal-2026-hotel/ Consultez les mises à jour ici : https://vcfed.org/vcf-montreal/

11 months

1
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eBay strikes again!!

by Bill Gunshannon

Just when I thought eBay couldn't get much stupider... I went out to see if I could find a current going price for PDP-11 Pedestal Boxes as I have a couple I would like to cull from my collection. I came upon this: DEC PDP 11/23 - BC needs Power Supply Repair, NO cards, Vintage DEC History $900.00 If it has no cards, what makes it a PDP-11/23 other than the paint on the front cover? Dead PSU? Looks like a $900 backplane to me. And that is making the assumption that the backplane is actually usable. :-) bill

11 months

16
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3 VCF's this weekend! Atlanta, Dallas, Australia

by Jeffrey Brace

Wow! There are 3 VCFs this weekend! VCF SE (Atlanta, GA) : https://vcfed.org/events/otherevents/vintage-computer-festival-southeast/ VCF SW (Dallas, TX): https://www.vcfsw.org/ VCF Down Under (Australia) : https://www.facebook.com/events/s/cvce-vcf-downunder-2025-planni/5904082869… Jeff Brace

11 months

7
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VCF Midwest 20 Pre-Tabling Announcement Announcement

by Jason T

The table request form for VCF Midwest 20 will open at 19:00 CDT next Friday, June 27th. Read the mailing list announcement here: https://list.vcfmw.org/w/TagW1e4K9x4Rl8wpSnorrA (and join the mailing list, too, if you haven't!) -jt

11 months, 1 week

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Bill Atkinson

by Murray McCullough

Bill Atkinson, a true early microcomputer pioneer, ca. 1984+, brought drawing on a computer screen and linking to external files a reality. He will be missed. Murray--

11 months, 1 week

8
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DEC backplanes

by Paul Anderson

I've been digging through a few shelves of backplanes looking for a specific one for a listmember. Along with the DD11-CK and DKs, I found a RK611 and RH11. I probably have the boards for both. Any interest? Also found a few DDV11-D which I think is a 6x9 hex qbus backplane, but it's been a while. If you need any backplanes (11/84, 11/44) or options (DR11-B, etc) now is the time! Also a lot of core memory and backplanes. Please contact me off list. Thanks, Paul

11 months, 1 week

1
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Tadpole Sparcbook 2

by Andreas Holz

Hi all, by surprise I got a Tadpole Sparcbook 2 some time ago. Sadly there seems to be almost no documentation available in the net for a Sparcbook 2, neither a technical/service nor a user manual, only for Sparcbook 1 and later models. I do have the following issues: - the battery pack is missing. I found two ressources, e.g. the CHM - but none does have any infos about the battery pack - The external power connector requieres 18V - no problem - After connecting the fitting power the Sparcbook does power up, the display is lit and the unit is trying to boot from the internat SCSI disc. Nevertheless the boot process is failing this is a good sign. - after trying to reboot the unit will be almost dead. While pressing the power on button the LEDs on the left upper side of the display will be lit shortly, but nothing else will happen. - trying to reboot an power on the same as above will happen If I'll keep the unit several weeks/months unpowered the unit will power up again - but of course will be stuck again while trying to boot from disk and the same semidead issues as noted above. I'm suspecting the TOD chip/battery is deads or are there any other sugegstions? Up to today I didn't have a look inside of the unit ... Does any have the manuals hidden in theirs shelves? Best Andreas

11 months, 2 weeks

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Re: Bill Atkinson

by John

In addition to everything already cited, he developed what is still my favorite dithering algorithm. Atkinson dither was probably optimized more for speed than anything, but I've always loved the look of it, and have even implemented it myself for that reason. R.I.P., sir.

11 months, 2 weeks

1
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Re: Tadpole Sparcbook 2

by Adrian Godwin

Tadpole were in Cambridge, weren't they ? https://www.computinghistory.org.uk/ have collected a fair bit of Cambridge history. I haven't found them very willing to search their archives but there may be individuals who have more time available, or they may have a resource problem in putting information online. On Fri, Jun 6, 2025 at 8:28 AM erik--- via cctalk <cctalk(a)classiccmp.org> wrote: > > > > Hi Andreas, > > great that there are still some people looking into the > old SPARCbooks from Tadpole. I have got a 3GX up and running. > > > Sadly there seems to be almost no documentation available > > in the net for a Sparcbook 2 > > Yeah, that is really sad. Also do not have got any information! > Just to report from my work on the 3 series ones (which are > probably not to different from the earlier ones): > > Mine works without battery pack, so there is some intelligence > in the battery pack (for power management), but using a power > supply it is working even without that pack! > > > - after trying to reboot the unit will be almost dead. > > While pressing the power on button the LEDs on the left > > upper side of the display will > > be lit shortly, but nothing else will happen. > > Hmm, that sounds strange and I never observed this due to > lost NVram values. But what I observed is the yellow/orange > Tantalum caps going bad in the small power supply piggy back > PCB inside the unit. A short prevents the notebook from > working (and sometimes even some inductors release smoke and > completely destroyong the PCB depending on which cap went > short). > After a longer time powered off, the faulty cap can recover > explaining your observation. Fortunately I had some spare > PCBs and replaced all caps in my live one which works nicely > now... > > Good luck, > > Erik. >

11 months, 2 weeks

3
2
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Re: ASR-33 Help and Parts Needed

by Gregory Beat

START with SIMPLE GREEN. For Old Plastics and Bakelite, I keep Mineral Oil available. Refurbishing the Teletype model 15 https://www.aetherltd.com/refurbishing15.html Teletype model 33 Wiki https://wiki.theretrowagon.com/wiki/Teletype_Model_33 Wayne Durkee, WB1FDW in Vermont is good Teletype 32/33 Resource He still repairs them ! https://www.qrz.com/db/KB1FDW greg, w9gb

11 months, 2 weeks

2
1
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Re: ASR-33 Help and Parts Needed

by donald donaldwhittemore.com

Any fluid you need is probably banned by local, state or federal government. :)

11 months, 2 weeks

3
2
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ASR-33 Help and Parts Needed

by Mike Katz

I was given an ASR-33 complete with stand, read & punch. This ASR-33 has been modified for RS-232 though a blue perfboard mounted in the connection enclosure (under the cover place where the dialer would be. Is has a DB25 ribbon cable coming off of this board. The perfboard does not have a label on it that I can find. The ASR-33 also has a 3 x 5 conductor rectangular connector coming out of the read of the unit with 6 female contacts installed. I was able to connect the ARS-33 to a VT-330+ at 110B 8-N-2 and send and receive on the teletype. The punch seems to work as well. The reader will "chatter" then the reader is put in the stop position and the tape out sensor is pressed but the sprocket does not advance and the reader pins to not move. Questions: 1. Why the reader is not advancing and the pins are not activating? Could this be a read enable contact not being in the active position? 2. What are the outs of the RS-232 DB-25. Other than TX, RX and GND 3. What are the pin outs of the 3 x 5 rectangular connector. I think this is the current loop and other control signals. Does any any of the items below for sale or have a 3D model I can print: 1. Roll Paper spindle (the spindle that the roll paper spins on) 2. Paper Tape Punch Spindle (the spindle that the paper tape spins on) 3. Paper Tape Chad feed tube 4. Paper Tape Chad Box I will be connecting this to either a PiDP-8/I or a PDP-8/E for now and eventually a PDP-8/L Thank you, Mike

11 months, 2 weeks

10
17
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Tadpole Sparcbook 2

by erik＠baigar.de

Hi Andreas, great that there are still some people looking into the old SPARCbooks from Tadpole. I have got a 3GX up and running. > Sadly there seems to be almost no documentation available > in the net for a Sparcbook 2 Yeah, that is really sad. Also do not have got any information! Just to report from my work on the 3 series ones (which are probably not to different from the earlier ones): Mine works without battery pack, so there is some intelligence in the battery pack (for power management), but using a power supply it is working even without that pack! > - after trying to reboot the unit will be almost dead. > While pressing the power on button the LEDs on the left > upper side of the display will > be lit shortly, but nothing else will happen. Hmm, that sounds strange and I never observed this due to lost NVram values. But what I observed is the yellow/orange Tantalum caps going bad in the small power supply piggy back PCB inside the unit. A short prevents the notebook from working (and sometimes even some inductors release smoke and completely destroyong the PCB depending on which cap went short). After a longer time powered off, the faulty cap can recover explaining your observation. Fortunately I had some spare PCBs and replaced all caps in my live one which works nicely now... Good luck, Erik.

11 months, 2 weeks

1
0
0 0

SWAP MEET IS ON! - UPDATE 6/5/25 - Wall, NJ

by Jeffrey Brace

Swap Meet Update 6/5/25 So the negotiations with the weather gods have been successful! The latest weather forecast shows a 57% chance of rain around 8AM and thunderstorms 5PM or later. So with this, I'm going ahead with the swap meet as planned. Everyone is encouraged to use their best judgment as to their safety in coming to the event. My highest recommendation is to bring a tent that can be anchored with sandbags. Generally a good idea regardless of rain. Also bring waterproof clothing (i.e. raincoats, etc.) If any vendor should feel uncomfortable and needs to cancel, we will refund you, but once you show up, there is no refund. Vendor setup is 7AM General Admission is 8AM More info here: https://vcfed.org/vcf-swap-meet/

11 months, 2 weeks

1
0
0 0

CTOS Ethernet EDL software

by r.stricklin

There is a copy of the Convergent CTOS EDL (ethernet data link / packet driver) for the ETH150 (SMC 8416T ISA ethernet) board on Bitsavers. I am wanting to make use of an SG410P (CTOS EISA Ethernet IOP) but as far as I can tell the EDL archived on Bitsavers is missing the piece(s) necessary for use with an IOP or other supported non-ISA ethernet board. Has another copy of the EDL survived? Can it be made available? It might be the case that it was included as a separate disk in another CTOS networking software package (e.g. TCP/IP, OSI Transport, or LANce). Secondarily, CTOS FTP has ISAM II as a pre-req; Bitsavers has (what appears to be) an update-only disk archived, but no “base” install. I’d be quite interested in finding out if that has survived and could be made available as well. If there’s a more likely mailing list or forum I might also direct my enquiries, I’ll be glad to engage there. Thanks! ok bear.

11 months, 3 weeks

1
0
0 0

ComputerVision input devices

by Alan Perry

Does anyone here have or know of ComputerVision CADDStation input devices (e.g., puck, tablet) that ard for sale? I have started restoring the CADDStation Model 32 that has been sitting in my garage for a while but am missing some pieces to get the full experience. alan

11 months, 3 weeks

2
1
0 0

RSX11M tape copy

by Peter Ekstrom

Hello all, I have transferred some simh .tap files to my PDP-11/23+ running RSX11M+. There I have tried to use VCP to attach them to a virtual device but I keep getting an invalid record format error. I then realized the simh .tap files most likely aren't organized correctly. If I attach them to TS0 in simh I can work with them. So now I am trying duplicate a tape into a new .tap file created using VCP. I can't for the life of me get it to work though. BRU doesn't support tape-to-tape and FLX doesn't complain but also never completes. Is there a process for tape duplication under RSX? The images were first transferred to my PiDP-11 using ftp in binary mode over TCP/IP. From there I used NFT in image mode and I tried both record and block modes. I have also seen the simh tape tools but there doesn't seem to be a tool to convert a simh file back to what would be on a real tape. Anyone have any information or pointers to get this to work? Thanks! -Peter

11 months, 3 weeks

10
18
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UPDATE: Swap Meet in Wall, NJ - June 7

by Jeffrey Brace

Swap Meet Update 6/4/25 Weather The weather on Saturday is being watched closely. A little rain is not concerning, but the thunderstorms are concerning. We will make a final call on Thursday at 10PM about what we will do. We will post updates here: https://vcfed.org/vcf-swap-meet Food Truck The food truck cancelled on us and we can't find a replacement at the last minute. We *may* have some solution to support at least the vendors and volunteers. The general public are on their own. Otherwise we have plenty of vendors signed up with lots of interest. We have been posting daily on Facebook & Instagram to tell everyone about the event. Lots of engagement, interest and excitement. Take care! Jeff Brace VCF/MARCH Fundraising Manager

11 months, 3 weeks

1
0
0 0

What was this AT&T SCSI enclosure for?

by Andrew B

I have an AT&T branded SCSI enclosure. Two half-height bays with the drives held vertically (on their sides), with a door that opens to expose one for a tape drive, activity lights labeled hard drive and tape, CN50 connectors, the AT&T beige and brown color scheme I associate with 3B's and 6300 PCs. No model number. Anyone have any idea what this was made for?

11 months, 3 weeks

11
23
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ASR-33 Help and Parts Needed - corrected message

by Mike Katz

I was given an ASR-33 complete with stand, reader & punch. This ASR-33 has been modified for RS-232 though a blue perfboard mounted in the connection enclosure (under the cover place where the dialer would be on the right side). It has a DB25 ribbon cable coming off of this board. The perfboard does not have a label on it that I can find. The ASR-33 also has a 3 x 5 conductor rectangular connector coming out of the rear of the unit with 6 female contacts installed. I was able to connect the ARS-33 to a VT-330+ at 110B 8-N-2 and send and receive on the teletype. The punch seems to work as well. The reader will "chatter" then the reader is put in the start position and the tape out sensor is pressed but the sprocket does not advance and the reader pins to not move. Questions: 1. Why the reader is not advancing and the pins are not activating? Could this be a read enable contact not being in the active position? 2. What are the pin outs of the RS-232 DB-25. Other than TX, RX and GND 3. What are the pin outs of the 3 x 5 rectangular connector. I think this is the current loop and other control signals. Does any one of the items below for sale or have a 3D model I can print: 1. Roll Paper spindle (the spindle that the roll paper spins on) 2. Paper Tape Punch Spindle (the spindle that the paper tape spins on) 3. Paper Tape Chad feed tube 4. Paper Tape Chad Box I will be connecting this to either a PiDP-8/I or a PDP-8/E for now and eventually a PDP-8/L Thank you, Mike

11 months, 3 weeks

2
1
0 0

TRS-80 BASIC oddity

by Bill Gunshannon

I am going to assume there are other TRS-80 people hanging out here and go ahead and ask this: Has anyone here used the DEFUSRx command? I tried to use it for something I am working on and it didn't work. So, I copied the example program from page 115 of the Model III Disk System Owner's Manual and, guess what, it didn't work either. 150 DEFUSR1 = &H7D00 returns a Syntax Error 150 DEFUSR1 = 32000 works fine. Anybody else ever run into this? I can't believe something as blatant as that could have gone on for all those years. bill

11 months, 3 weeks

9
16
0 0

USDC Unibus SCSI Controller

by emanuel stiebler

It is few years that anybody asks, so here it is again: ANYBODY has any manuals for it? On Discord, we have some discussions, I found some of them in my boxes, but nobody has documentation, and no success to get them working. Any chance?

11 months, 3 weeks

1
0
0 0

IBM 5100 side scroller (PALM processor)

by Steve Lewis

I've written a "side scroller" program using the IBM 5100's native PALM instruction set. I talked about the 5100 in 2023, and for 2025 I wanted to present something special for its 50th anniversary. I kept getting sidetracked with other projects over the year. But thanks to the IBM 5100 emulator now in MAME, that helped a lot in debugging the program more efficiently. There is much I still don't fully understand about PALM, so I probably do this in the most efficient way, but it does work well. I'm also still working towards restoring a POLY-88 (8080 based system, similar to SOL-20 as far as being S-100 based). Someday I'd like to attempt a similar side-scroller on that platform, to see how the performance compares and if a micro that early could handle it (at 1.8MHz and will need to find 16KB of working RAM- one thing about the IBM 5100, it feels fairly rock solid after 50 years). Unless anyone already has a working 8080-based system and wants to take a stab at this? I'll talk more about the design approach (and use of PALM instruction set) after VCF next month. Here is the YouTube video preview of this scroller in action on real hardware: https://www.youtube.com/watch?v=sRAxKGkXC1I And the Rumble version in case anyone has issues with YT: https://rumble.com/v6tu80h-ibm-5100-vertical-side-scroller-hardware-demonst… If anyone has a 5100 with the "expansion feature" and async card, we're always interested in trying to get old system "online" (through WiModem type devices), or a non-working 5100 is always good for spare parts on the ones that do still work. But one "fabled accessory" of the 5100 is it's carrying case -- which surprisingly was the cheapest item on its price sheet (at $150 new). I've only seen one of these once (in Florida), so they do exist. Or tapes (even later 3M QIC DC6120 are compatible). Cheers, Steve

12 months

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Board repairs?

by Peter Ekstrom

Was there someone on this list who can help repair boards, like the RQDX3s I broke in my H9278? I don't know if it would be too costly, but if not I'd like to restore them to working condition. -Peter

12 months

2
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Problems with an RQDX3 in an 11/23.

by Peter Ekstrom

Hello to the group, I have been banging my head against a PDP-11/23 where I have an RQDX3 I'm trying to get to work. Actually, I have two RQDX3's but only one at a time. It is configured to the factory CSR, 172150, and it has the latest microcode on it. When I run the XXDP ZRQCH0 formatter I get the following: RQDX3 Disk Formatter Utility UNIT IS Formattable Winchester (RDnn) or Floppy (RX33) Drives RSTRT ADR 145702 DR>STA CHANGE HW (L) ? Y # UNITS (D) ? 1 UNIT 0 Enter controller IP Address (O) 172150 ? What unit do you want to format [0-255] (D) 0 ? Would you like to revector a single LBN only [Y/N] (L) N ? Do you want to use the "AUTOFORMAT" Mode [Y/N] (L) Y ? N ZRQC SYS FTL ERR 00006 ON UNIT 00 TST 001 SUB 000 PC: 105742 Fatal Controller Error During Initialization. ZRQC SYS FTL ERR 00006 ON UNIT 00 TST 001 SUB 002 PC: 105742 Fatal Controller Error During Initialization. ZRQC EOP 1 2 TOTAL ERRS DR> I have been booting XXDP and also RT11 over an emulator TU58. And I have a BDV11 so it has an LTC. I did try downgrading the microcode on the RQDX3 to the previous version, 3. It was 4. But no luck. Am I missing something? This should work with an M8186 CPU board, right? Anyone have any ideas? I haven't yet, but I plan to pop one of these RQDX3s in my 11/23+ and see if it works there. -Peter

12 months

3
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Re: IBM 5155

by Phill Kennedy

Bill, Please update your email on QRZ.com to a working email address. Thanks Phill, a fellow ham.

1 year

2
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IBM 5155

by Bill Gunshannon

I just managed to score a 5155. Well, soon, it is waiting for me to pick it up at the University where I used to work. It looks to be in really good shape and has been in storage for probably two decades or more. A couple quick question for anyone familiar with this system. Is it likely there is one of those little batteries on it that would now be dead and need replacing before I try to use it? And, also, would this have a floppy controller on it that was capable of reading and writing disks from systems like the TRS-80 with an SD boot track? Inquiring minds want to know. :-) bill

1 year

7
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Comstar Computer Systems System 4 Intel 4004 based Industrial Computer

by Christian Liendo

Back in Nov of 2023 Ed Sharpe asked the following: “Was there ever a COMPUTER using a 4004 that you could really do something or did that finally arrive with the 8008” https://classiccmp.org/mailman3/hyperkitty/list/cctalk@classiccmp.org/messa… I hope to answer that question, or at least spark a discussion. For a number of years now I have been researching this computer called a Comstar System 4 which is based on the Intel 4004. The Comstar Corporation of Minneapolis was a developer of microcomputer control and automation systems and in 1972 released the System 4 microcomputer. Comstar built a general purpose capable computer that could be programmed to do a multitude of tasks but their market focus was industrial automation. Comstar was eventually bought by Warner & Swasey in 1974 to integrate their computers into the Warner & Swasey product line. Warner & Swasey was a huge manufacturer of industrial machines. So they bought Comstar to be their Computer division. In fact it was called " Warner & Swasey Comstar Microcomputer Electronic Products" Warner and Swasey also licensed the Micral N to do the same and we call the Micral N a computer. The Micral N was designed for process control, but we know of it as a computer. Now before anyone argues about if this is a computer or not, I will state the following. It was called a Microcomputer in the ACM titled "Development of a portable compiler for industrial microcomputer systems " It was called a Microcomputer in Electronics Magazine July 11th 1974 It was listed as a Microcomputer in "Auerbach Guide to Minicomputers" April 1976 & Winter 1976 - 1977 It was listed as a Microcomputer in Datamation Magazine Dec 1974 It was called a Microcomputer in "A MICROCOMPUTER BASED SUBSTATION CONTROL SYSTEM" The University of Oklahoma, Ph.D., 1975 Engineering, electronics and electrical Page 90 It was listed as a Microcomputer in the Intel MCS 4 User Manual Feb 1973 page 171 It was listed as a Microcomputer in Electronics Magazine Jan 1973, they promote the 4004 and 8008 and use the System 4 as an example. The reality is this existed, was 4004 based and there were discussions about it in the media at the time. Anyway I wanted to see if there was more interest in researching this computer. I listed a number of articles and references below that either discuss Comstar, The Warner Swasey Computer Division, the “System 4” or “Star 4” Computer. All the Manuals and schematics I was able to upload to archive.org https://archive.org/search?query=subject%3A%22Comstar+Computer+Systems%22 Computer History Museum's Archive of the Manual https://www.computerhistory.org/collections/catalog/102686568 Pictures of the items I have collected so far https://imgur.com/a/Oyts3A9 The website "Internet Scripophily Museum of Computing" has a page on the history of The Warner & Swasey Company. It's a decent timeline of the company http://ismoc.blogspot.com/2017/06/the-warner-swasey-company.html "Development of a portable compiler for industrial microcomputer systems" by LEROY H. ANDERSON The Warner & Swasey Company, it discusses the system and has images on the unit. https://www.computer.org/csdl/pds/api/csdl/proceedings/download-article/12O… In the ACM's archives "Development of a portable compiler for industrial microcomputer systems" by LEROY H. ANDERSON The Warner & Swasey Company, it discusses the system and has images on the unit. https://www.computer.org/csdl/pds/api/csdl/proceedings/download-article/12O… Electronics Magazine July 11th 1974 Article: Industrial Automatic control proliferates, they are mentioned on page 84 & 85 https://www.worldradiohistory.com/Archive-Electronics/70s/74/Electronics-19… There is a mention about the compiler in the IEEE on Page 25 under Compiler Programmer https://ieeexplore.ieee.org/stamp/stamp.jsp?arnumber=6368812 Computer Design Magazine Nov 1975 Page 129 they talk about the compiler. https://archive.org/details/bitsavers_ComputerDe_90611286/page/128/mode/2up The Intel MCS 4 User Manual Feb 1973 page 171 and in Electronics Magazine Jan 1973, they promote the 4004 and 8008 and use the System 4 as an example. http://www.bitsavers.org/components/intel/MCS4/MCS-4_UsersManual_Feb73.pdf https://www.worldradiohistory.com/Archive-Electronics/70s/73/Electronics-19… There are a number of sources that list the computer as a "microcomputer" and provide specs showing it being 4004 based. Datamation Magazine Page 97 & 101 http://www.bitsavers.org/magazines/Datamation/197412.pdf In "Auerbach Guide to Minicomputers" April 1976, the computer is mentioned on page 54 and page 70. http://www.bitsavers.org/pdf/auerbach/Auerbach_Guide_to_Minicomputers_Apr76… In "Auerbach Guide to Minicomputers" Winter 1976 - 1977, the computer is mentioned on page 32 http://www.bitsavers.org/pdf/auerbach/Auerbach_Guide_to_Minicomputers_1976-…

1 year

7
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Re: IBM 5155

by Ali

>Is it likely there is one of those little batteries on it that would>now be dead and need replacing before I try to use it?>Congrats and no. This is your std XT (5160) MB just shoved in a case with a handle and monitor.>And, also, would this have a floppy controller on it that was capable>of reading and writing disks from systems like the TRS-80 with an SD boot track?>If it works on an XT it will work on a 5155. If not then no.

1 year

1
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DEC MAD-11

by hupfadekroua

Hi All, In my collection I do have a blinkenlight front panel with a label MAD-11. Based on the adress and data switches the system should be of 18 Bits wide. I don‘t see any kind of references or links to docs while querying the internet. Does some of you have any information or hints available? A.

1 year

3
3
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Philips P3800 key lock swtch

by Tony Duell

Does anyone know anything about the key lock on the mains on/off switch of the P3800? I have one without a key. I can't identify the lock manufacturer (no markings on it at all) so I've not been able to get a blank to cut a replacement key. A friend who is a locksmith said she'd never seen anything like it. Any ideas who made the lock itself? Were all P3800 machines normally 'keyed alike' If so, a copy of an existing key (anyone have one?) would be a great help. Yes, I can trvially bypass the lock/switch mechanically or electrically. But I want to try to get this thing as original as possible. -tony

1 year

27
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Wanted: DEC ba23 or ba123 chassis

by lbmgmusic＠gmail.com

I am building up a micro vax and need an empty chassis. Given the number of dec boards on ebay, I assume (hopefully) that there are some empty chassis out there. Please PM if you know of an option. tnx jc

1 year

10
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Re: Finding a Honeywell 316?

by Adrian Stoness

digging through emails and just found this again strangely i have the h316 manuals from lynn lake found them in my house i bought in 2017 did some digging around to find the system but it got tossed out in 2016 apparently argg On Sat, Jul 21, 2012 at 10:39 PM Paul Anderson <wackyvorlon(a)me.com> wrote: > My father worked in a mine in the '70s that was using a Honeywell 316 for > process control. I was thinking it might be neat to see if I could track > one down. What are they worth the days? How common are they? > > Sent from my iPad >

1 year

5
8
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Wanted: DEC ba23 or ba123 chassis

by lbmgmusic＠gmail.com

I am building up a micro vax and need an empty chassis. Given the number of dec boards on ebay, I assume (hopefully) that there are some empty chassis out there. Please PM if you know of an option. tnx jc

1 year

1
1
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Wanted: 64Mb 72-pin, single sided, non-ecc, non-parity SIMMs. 3.3V and 5V tolerant or 5V

by Anders Gustafsson

Asking for a friend �� Reason is this... I built an expansion board for the HP1000 A-series. I found some modules on eBay that work fine for me, but a friend that built the board have had probems finding and yes, most of the vendors on eBay do not know what they are selling and the picture might not match what you get. So I am asking here if anyone has a module they might want to part with. The board design is here: https://www.dalton.ax/hp1000/memory/ -- Med vänlig hälsning Anders Gustafsson, ingenjör anders.gustafsson(a)pedago.fi | Support +358 18 12060 | Direkt +358 9 315 45 121 | Mobil +358 40506 7099 Pedago interaktiv ab, Nygatan 7 B , AX-22100 MARIEHAMN, ÅLAND, FINLAND

1 year

1
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Skype

by Murray McCullough

It is with some sadness to here of Skype's demise even though MS owned it. It's not necessarily on topic of 'ancient' personal computing but then again maybe it is! Happy computing, Murray 🙂

1 year

12
17
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Summer house keeping.

by Jerry Wright

I have some more thing to move out of my shop. These are in Kent Washington. most are too big to ship. Hp 1000f 2117f computer. Lots of boards. Unknown condition. looks good. 400.00Hp 2753a Paper Tape 100.00Hp 7906 drive 200.00 HP 7970e Tape HPIB interface in cabinet 100.00HP 7970B tape 50.00 HP 9000/380 in Desk side Cabinet with drives and Hi-Res graphics 250.00 Intel 310 development system 200.00 General Automation computer 100.00 HP K-210 server works with drives in a Rack Free Sun 4-260 desk side computer. No drives. missing top cover. did boot 200.00 Dec 11/44 loaded with boards in Rack, comes with 2) RA-80's, 1) TU80 in 42" rackHas 2 RA81 and 2 RA 91 drives.( loose), + a second 42" cabinet, with a 11/44 chassis, (no Boards) with a Power supply. (mint) Computer has booted in the past, but now has 12v power supply issues 600.00 Dec 11/34 Chassis and Boards 300.00 Nova 3 Chassis, Front panel and Boards 450.00 Nova 4 Chassis and boards 200.00 3 DG Desk Top computers. made out of modular units connected together like model 10/20 Style 50.00 each Altos 486, 586, 5-15AD desk tops computers 50.00 each Private Mail please with questions and or requests. most have not been turned on. Some have but years ago. All stored in a heated shop. - Jerryg-wright(a)att.net

1 year

9
12
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VMR question for RSX11M and DECnet CEX

by Peter Ekstrom

I am putting together a PDP-11/23 and have a working RSX-11M 4.4 OS running in simh while I wait for a few parts. I want DECnet as well. I have the 4.7 kit and have done a netgen, but I can't install it because I don't have the CEXPAR partition in my system image. I have gone over the VMR command in the manual a few times and tried various things to try and create the partition in my image, but have not been successful. I assume (from looking in the manuals) that I either need to create that partition in my image, or make room for it? The netgen process has the defaults of 113500 as the base and 4300 as the size. VMR complains about 'non-existing memory' for the base and if I try the wild card I get 'alignment error'. I have 512KW of memory that I plan to use in the real machine, so simh is configured with that as well. Any pointers would be greatly appreciated. -Peter

1 year

13
14
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Uploading PDFs to Bitsavers

by Christian Liendo

I'm sorry if this has been asked before. How can I send PDFs to Bitsavers? I know I cannot just FTP and create a directory. I am looking on the website but I am probably not reading what is right in front of me. Any help would be appreciated.

1 year

4
3
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Wang TTL BASIC

by Steve Lewis

Is anyone out there familiar with the Wang 2200 BASIC? Of about 1973/1974 C. Corti, I think you still have one of these complete and runnable? My question is, was its basically really "built" using TTL logic/chips? The system didn't really have a microprocessor (neither did the early Alto, right?) I recall that system had many boards, the whole "CPU" box was external to the monitor (and in the earliest versions, the power supply was also a large external box). I can't really fathom creating a BASIC out of raw TTL, or maybe I'm misunderstanding the approach. -Steve

1 year

15
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Wang TTL BASIC

by Bob Yates

Schematics for your viewing pleasure. More detailed information can be found in other parts of the website. https://www.wang2200.org/schematics.html

1 year

1
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PDP-11 hardware clock

by Peter Ekstrom

Hello PDP-11 Gurus, I am looking for a better time-keeping alternative than the LTC in my PDP-11/23-PLUS. Is the KWV11-C card the best option for that or are there other options? I have looked around a bit and have seen some other RTC boards but don't know if they would work. -Peter

1 year

9
19
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Re: Looking for an IF-20 interface for an Brother AX-45 typewriter

by Stefaan Ponnet

I'm attempting to interface with the 15-pin connector on the AX-45. I'm assuming it uses a similar protocol as the IF-50 / IF-30 interface which has been described in other forums https://forum.classic-computing.de/forum/index.php?thread/29023-panasonic-r… and has a working interface emulation https://www.youtube.com/watch?v=1UJ5cyvNC_M I opened up the typewriter and traced the pins of the 15-pin centronics connector. So far I came up with this pin 1 : GND pin 2 : connected to the IC + has a pulldown resistor pin 3 : GND pin 4 : connected to the IC + has a pulldown resistor pin 5 : GND pin 6 : connected to the IC + has a pulldown resistor pin 7 : GND pin 8 : N/C pin 9 : N/C pin 10 : connected, but haven't been able to trace yet pin 11 : connected, but haven't been able to trace yet pin 12 : connected, but haven't been able to trace yet pin 13: N/C pin 14: N/C pin 15: N/C Probably these pins map to DATA CS CLK and ACK But this is still a work in progress - If we can figure out how to get the typewriter to listen to our commands we're one step closer to getting it to print.

1 year

1
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Re: Wang TTL BASIC

by cclist＠sydex.com

The Packard-Bell PB440 (1963) was microprogrammable: https://bitsavers.org/pdf/packardBell/PB-440/SP-149A_PB-440_microprogrammin… Various earlier systems used microprogram-like techniques, but I don't know how many were earlier than PB in their use of the word. Was the PB-250's floating point microprogrammed? --Chuck

1 year

1
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Mac SE disk cleaning

by Brian Knittel

Passing on a request: anyone know of a way to erase user data off a Mac SE hard disk that will leave the disk and Mac OS intact? The machine works and could go to a new home but has privileged medical data on it so just deleting files isn’t sufficient — the free space has to be overwritten. Are there any utilities available on floppy disk that could do it? Plan B is taking a sledgehammer to the drive, but seems a waste to go right to euthanasia if there’s another option.

1 year

7
6
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QRAM-2 SAB-1 manual?

by Peter Ekstrom

So I have one of these boards, but I haven't been able to locate a manual for this specific one. Does anyone have the manual for this specific board? - Peter

1 year

1
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kennett classic surplus sale open, NeXT cube for sale, more.

by Bill Degnan

https://www.kennettclassic.com/surplus/ Lots of items remain. Priced cheap for pick-up only Also have a complete NeXT cube with display, mouse, keyboard. SCSI2SD card harddrive installed. Works $2700. Will consider shipping this. Contact me privately with questions. Bill

1 year

1
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Compute's Gazette returning

by wrcooke＠wrcooke.net

I saw on the BASIC Programming group on FaceBook that a new venture is going to start publishing Compute's Gazette again. https://www.computesgazette.com/ Perhaps interesting to some of you. Will You just can't beat the person who never gives up. Babe Ruth

1 year

8
7
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2.5" PATA drives

by Van Snyder

I have some working 2.5" PATA drives 30GB - 1 40GB - 3 60GB - 2 80GB - 2 100GB - 1 They're yours for a PDF of a shipping label.

1 year

1
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decuslib.com

by Henry Bent

Hi all, Is anyone else having trouble with decuslib.com? I can connect but I never get a response from the server. -Henry

1 year

3
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VCF MW talk open

by Steve Lewis

This past Saturday at a local retro meetup, it was announced there was still at least 1 open spot for a speaker/presentation at VCF SW (Dallas) this June. Just passing the word, if anyone is in the area at that time and interested to speak on a topic vintage-computing related. There should be a signup at the VCF SW page.

1 year

1
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VCF Swap Meet June 7, 2025 in Wall, NJ

by Jeffrey Brace

https://vcfed.org/vcf-swap-meet/ Jeff Brace

1 year

1
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Re: Digital Intelligence UltraBlock-SCSI bridge to USB/FW

by John Foust

At 11:34 PM 4/24/2025, Travis Pierce via cctalk wrote: >I just now used one tonight to image a JAZ disk that I found. I used DD on >a modern Linux box. These little bridges do come in handy and are pretty >convenient. I really like mine quite a bit. I was hoping they just present the SCSI drive as a block device to the operating system, did not require proprietary software, and that they'd work under modern Windows as well. >My only criticism is that >once you have it all connected (USB, Power, SCSI Drive) there are >literally wires everywhere, but that's just how SCSI was. And then there's the blood sacrifice. Fortunately I have bales of cables. At 10:19 PM 4/24/2025, Henry Bent wrote: >Oh, one more click and I would have gotten there...Â <https://web.archive.org/web/20060831144110/http://www.digitalintelligence.c…>https://web.archive.org/web/20060831144110/http://www.digitalintelligence.c… That is the bridge for forensically reading USB devices. Mine is for SCSI devices, like this: https://www.ebay.com/itm/387890903599 or https://web.archive.org/web/20060421102553/http://www.digitalintelligence.c… I looked at https://web.archive.org/web/*/http://www.digitalintelligence.com/files/* but did not see the UltraBlock model "T4" manual. - John

1 year

3
2
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GRiD archive anywhere?

by Steve Lewis

Been messing around with a GRiD system recently - I'm not seeing a solid archive of things like PDFs and ROMs for that system. And I've heard a rumor there used to be one, but it went offline a few years back? Mostly I'm looking for GPIB related info, and maybe either native GRiD drivers or some compatible MS-DOS drivers to use the GPIB port on that system. Here some images and reference info of what I've learned so far about a late-model (but before Tandy) GRiD system... https://forum.vcfed.org/index.php?forums/grid-systems.82/ I'm also hunting around for one of those GRiD disk drives, if there is any spare standalone one not bundled with another existing system. -Steve

1 year

2
1
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Re: Digital Intelligence UltraBlock-SCSI bridge to USB/FW

by John Foust

I found the manual: https://web.archive.org/web/20100215085042/http://www.digitalintelligence.c… As it was sold as part of a kit of three. - John

1 year

3
2
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Digital Intelligence UltraBlock-SCSI bridge to USB/FW

by John Foust

I was curious and had a spare benjamin for one of these from eBay, thinking it would be a handy USB to SCSI adapter for convenient imaging of old drives, as it was mentioned as one a month or two ago on the Reddits. I'd like to find a manual and hear anecdotes. Mine is a model T4, has USB 2.0 and Firewire 800, circa 2005. I was surprised to see they were made in New Berlin, WI. I don't see any mention of this model on their web site https://digitalintelligence.com/ nor any mention of "ultrablock" in my CCtalk archives. - John

1 year

3
3
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Converting raw images to floppy images

by Bill Gunshannon

Can anyone here tell me what tool I can use to create DSK, DMK or IMD files from files with the extensions "raw" and VOL? I am once again trying to get the CPM Adaptable System for UCSD Pascal to work on an emulator. I would also like to try and get the PDP-11 version of UCSD Pascal running again and that requires the same ability. bill

1 year

4
3
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2.5" disk drives

by Van Snyder

I have several 2.5" disk drives, some PATA, some SATA, ranging from 9GB to 130 GB. Do you need any? Send a PDF for a shipping label.

1 year

1
0
0 0

3.5" mounting brackets

by Van Snyder

I have mounting brackets for 3.5" disk drives in an Antec Sonata III 500 case. They're nice metal trays with mounting holes on the bottom and spring metal clips on the sides to hold them into the panel inside the case. For some reason, I have six of them, but the case has only four slots. Does anybody need them? https://archive.org/details/manualzilla-id-7235982

1 year

1
0
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Paul Anderson?

by Tom Hunter

I have been talking with Paul Anderson about some PDP-11/05 parts. End of January Paul wrote about medical problems and possible surgery. I have not been able to get in touch with him since and hope he is OK. Has anyone here heard anything about Paul since January? Thanks Tom

1 year

3
2
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RS232 Spec

by Steve Lewis

Hey gang, a few months ago I had found the 1968/1969 document spec of RS-232. But now, I'm unable to find it again ! At Internet Archive, there is one link/reference to it, but it appears to just be the cover page (which does have the date of August 1969). I see the EIA RS-232-C spec dated from 1991 (but I think that date is just marking when EIA took over stewardship of the standard, but the spec should reflect/match the original 1969 one). In the manual for the DataSet 103C (from a few years earlier than 1969), it outlines signal lines all labeled like RS-232. But I wouldn't call it an RS-232 spec. Like most standards, it takes a number of years for a community/critical mass of products to understand it and adopt it correctly. Even ASCII wasn't globally recognized and adopted until maybe 15 years after it was introduced? So I was trying to track down the "earliest mention" of RS-232, to pinpoint it really being from 1962. Technically it appears the EIA "guards" that spec, and makes it expensive to officially download it. Maybe they took an initiative to try to scrub earlier editions from the public web, maybe that's why it's harder to find now? But I was pretty sure I found a scanned copy of it at some point (the Aug 1969 one). If anyone happens to have a printer version (of a 1969 or earlier RS-232 spec) - it would at least be nice to know that exists somewhere. I'm pretty sure that "original spec" called out +/- 3 to 25V, later ones maybe used 20V or 15V. -Steve

1 year

11
21
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PDP-8 and PDP-12 Paper Tape Images Posted (Re: Paper Tape Reader Needed)

by Jay Jaeger

I have posted my PDP8 and PDP12 paper tape images onto my Google Drive (where they are also available to CHM/Al Kossow for their "bits" collection. https://drive.google.com/open?id=0B2v4WRwISEQRWWFFdVpCZWFTZEU&resourcekey=0… Look in bits/DEC/pdp8 and bits/DEC/pdp12 for folders "From_JayJaeger". There is a PDF of the contents of BOTH directories in each one (it is the same PDF in each case). JRJ

1 year, 1 month

2
1
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Re: RS232 Spec

by donald donaldwhittemore.com

FWIW, both Grok and ChatGPT say the same thing. The RS-232 standard was first described in 1960 by the Electronic Industries Association (EIA). Its full original designation was EIA RS-232, where “RS” stands for Recommended Standard.

1 year, 1 month

3
2
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Looking for Tiny BASIC Extended source code

by Eric Scharff

Many years ago (March 2007 to be precise), I posted to this mailing list because I had typed in (by hand) the octal listing of TBX (Tiny BASIC Extended) from Dr Dobbs Vol. 1 No. 1, pp 16-17( It turns out that this 8080 code basically worked and I was able to verify it in a Z-80 simulator. Fast forward to 2025, and I have rediscovered this code and posted it to GitHub. I have also included an 8080 emulator in JavaScript so you can run TBX in your browser: https://github.com/ericscharff/tinybasic While keying in two pages of octal listings was an interesting exercise, I’m less keen to type in the source code for TBX, which appeared in Vol 1 No 2, pp 13-31. I’d like to preserve this source code alongside the octal dump in my github repository. Does anyone happen to have a listing of this source code in ASCII, or perhaps access to high quality OCR software that could perhaps automate the job? The closest I can find is on Whipple’s own web site athttps://whippleway.com/Source_Code/TBX.asm Which seems quite close, but is missing things from the first TBX (e.g., FOR / NXT loops) Many thanks, -Eric

1 year, 1 month

1
0
0 0

SLIP TCP/IP stack for PRO/VENIX

by Cameron Kaiser

Way back when, I asked on the list about null modems for the DEC Pro which I planned to use for experiments with SLIP. PRO/VENIX doesn't have any network capability other than UUCP, and it doesn't seem like anything else supports the Ethernet CTI card other than P/OS (of course) and the unofficial 2.9BSD, but I like PRO/VENIX V2.0 better because it's a real System V. Anyway, here's a simple implementation with four clients (ping, DNS, NTP and command-reply TCP) which runs over the printer port at the standard 4800bps. That keeps the main serial port free as a second terminal and for Kermit. Getting it to work with both the PRO/VENIX Rev. 2.0 and V2.0 compilers (i.e., older-than-V7 and System V respectively) was interesting. Unfortunately Xhomer's serial port emulation isn't good enough for this yet; many dropped bytes. It works fine with my real DEC Pro 380. https://oldvcr.blogspot.com/2025/04/lets-give-provenix-barely-adequate-pre.… https://github.com/classilla/bass -- ------------------------------------ personal: http://www.cameronkaiser.com/ -- Cameron Kaiser * Floodgap Systems * www.floodgap.com * ckaiser(a)floodgap.com -- God made the integers; all else is the work of Man. -- Kronecker -----------

1 year, 1 month

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VCF East 2025 Survey Results

by Jeffrey Brace

VCF East 2025 Survey results: https://www.surveymonkey.com/stories/SM-chUD9AoxbzNkIk230AwghQ_3D_3D/ Jeff Brace VCF East Showrunner

1 year, 1 month

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System Source Swap Meet April 26 & 27, 2025 (Hunt Valley, MD)

by Jeffrey Brace

More info here: https://ca.syssrc.com/wp/?page_id=105&civiwp=CiviCRM&q=civicrm%2Fevent%2Fin…

1 year, 1 month

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VCF East photo gallery

by William Sudbrink

Commodore Z has put up a very nice gallery of photos of VCF East 2025: https://www.commodorez.com/VCFEXX/index.html Bill S. -- This email has been checked for viruses by Avast antivirus software. www.avast.com

1 year, 1 month

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RK11-D register address assignment

by Jos Fries

The "RK11-D and RK11-E moving head disk drive controller manual" (EK-RK11D-MM-002) states in par. 2.5 (Installation Procedure) that the register and vector addresses of a RK11-D can be configured by "seven interrupt vector address jumpers and eight address selection jumpers of the M7257". The manual however doesn't state the address range that can be configured by these jumpers and refers to engineering drawing D-CS-M7257-0-1 for that information. I found these drawings in the RK11-D Engineering Drawings but cannot find information in them on the valid address ranges. Therefore my question: what is the address range a RK11 controller can be configured for?

1 year, 1 month

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Looking for VAX/VMS v4.x Software

by Christian Gauger-Cosgrove

Greetings, Long story short, as the subject line says, I'm looking for some VAX/VMS v4 era software. I've been working on putting together a "turnkey" VMS v4.7 system — I've mentioned it over on the SIMH mailing list once or twice, and if anyone is on the ClassicCMP Discord server, Mainframe Enthusiasts Discord Server, or DEC Discord¹, you've likely seen me mention it multiple times — and I'm currently trying to copies of some of layered products. To the crux of the issue, does anyone here have — as an image, or media that they are are willing to image/have imaged — the installation media for the following software for VAX/VMS v4.x? • VAX NOTES • VAX P.S.I. • VAXset/DECset — specifically the Language Sensitive Editor • CGRAF and CIMI And just because I have a deep loathing for myself: • Eunice I'm also always open to any other software for VMS v4.x if anyone has any they want to share. Best regards, Christian ¹: "The Digital Equipment Corporation Fan Spot", as it's named properly. -- Christian M. Gauger-Cosgrove STCKON08DS0 Contact information available upon request.

1 year, 1 month

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ThornEMI Datatech 9800 9-track tape drive

by Lothar Schröder

G'day, I have a ThornEMI Datatech 9800 9-track tape drive. Has anyone a user- or service-manual or a description how to load a tape? This drive can load the 7" 9-track tape reels and has an industrial interface with edge-connectors P1 and P2. Thanks in advance Lothar

1 year, 1 month

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VCF West 2025, Exhibit Registration Open - August 1-2 - Computer History Museum

by Jeffrey Brace

VCF West 2025 Exhibit Registration Now Open!!! VCF West is August 1-2 at the Computer History Museum Register an exhibit here: https://forms.gle/vQj4PUJCidjFt9GF8

1 year, 1 month

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Is the mailing list down?

by Tom Hunter

I have received no messages for a while. Is the list down? Thanks Tom

1 year, 1 month

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classiccmp test mail

by P Gebhardt

Hi list, since I am not getting any emails from our classiccmp mailing list anymore since mid of March, I would like to send this test email and see if it arrives and gets back to me. Appologies for the noise created. Pierre ----------------------------------------------------------------------------- http://www.digitalheritage.de

1 year, 1 month

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Re: Paper Tape Reader Needed

by Anders Nelson

Oh right, that's an important piece haha. I imagine fusing that Arduino project mentioned earlier in the thread with an SPI RAM chip and little extra firmware should be able to grab any length of tape one may have. -- Anders Nelson On Sun, Apr 13, 2025, 4:59 PM Mike Katz <bitwiz(a)12bitsbest.com> wrote: > Plus the circuit and software to operate it and convert the data to serial > or USB CID. > > On Apr 13, 2025 3:10 PM, Anders Nelson via cctalk <cctalk(a)classiccmp.org> > wrote: > > Here's a super cheap reader assembly you could bolt to a board, then hang > your supply reel from a bolt stuck in it if you're looking for the lowest > cost option: > > https://www.ebay.com/itm/224491588288 > -- > Anders Nelson > > On Sun, Apr 13, 2025, 6:49 AM Martin Bishop via cctalk < > cctalk(a)classiccmp.org> wrote: > > > The Sanyo Denki readers I have known use sprocket wheel feed, an > > additional means of damaging tapes. > > > > The Fanuc readers use a friction pinch, "rubber on steel", so they can't > > "saw" the tapes. > > > > Perhaps a consideration - if one has a choice > > > > Martin > > > > -----Original Message----- > > From: Chuck Guzis via cctalk [mailto:cctalk@classiccmp.org] > > Sent: 13 April 2025 02:18 > > To: Ethan Dicks via cctalk <cctalk(a)classiccmp.org> > > Cc: Chuck Guzis <cclist(a)sydex.com> > > Subject: [cctalk] Re: Paper Tape Reader Needed > > > > My PT reader is a Sanyo Denki, from a piece of CNC gear. (Bitsavers has > > some docs on those), Added a +5/+24 power suppy and a STM32 "Blue Pill" > > MCU interfacing as a USB communications device. > > > > Easy peasy and woks a treat. > > > > --Chuck > > > > >

1 year, 1 month

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Re: Selling Off My Q-Bus Collection

by donald donaldwhittemore.com

You may want to contact Dave. I believe he is doing things with this stuff. Ex-Microsoft software engineer. On X he is <https://x.com/davepl1968/status/1683904668127358976?s=58> Dave W Plummer<https://x.com/davepl1968?s=58> ⁦‪@davepl1968‬⁩<https://x.com/davepl1968?s=58>

1 year, 1 month

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VCF East 2025 is on The Verge!

by Jeffrey Brace

https://www.youtube.com/watch?v=4BTxddKZbhA VCF East was a great success with great speakers, exhibitors, classes, consignment and attendees! Thanks to all the volunteers who helped make this show happen. I couldn't have done it without you! Also check out other videos from VCF East: https://vcfed.org/vcf-east-2025-videos/ and articles on the show: https://vcfed.org/vcf-east-2025-articles/ Jeff Brace VCF East Showrunner

1 year, 1 month

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Re: Paper Tape Reader Needed

by Martin Bishop

Folks The jpg I posted previously https://www.emeritus-solutions.com/papertape/fanuc/Pic16F13145FanucInterfac… says it all cryptically To unpack the approach: - ex CNC machine paper tape readers are available, the Fanuc ones are both common and susceptable to house training - so 1) is buy a fanuc PTR + interface : part nos and current picks below - the required supplies are 200 V 50/60 Hz ~23W, 24V DC at ~1A2, 5V DC ~325 mA - the Fanuc interface board is https://www.emeritus-solutions.com/papertape/fanuc/A20B-0007-075D_Ptr_Inter… series 74 TTL IO - my interface bodgit uses a PIC16F13145 EVB as it has 5V IO (which is just the thing for series 74) and some CLBs (a joke, but you have to walk the ground) - so 2) you need a https://www.microchip.com/en-us/development-tool/ev06m52a to convert parallel octets into serial output - the interconnect board is connectors and wiring, the one illustrated is built for ease rather than compactness - so 3) DIY time, [DrB] the wire list for marrying PTR and PIC[DrB] is in the .zip - a project archive for the PIC containing sources and binary is available for download https://www.emeritus-solutions.com/papertape/fanuc/FanucInterFace1.zip should contain working code for MPLAB/X - my Fanuc zoo https://www.emeritus-solutions.com/papertape/fanuc/visualise.php depicts the interconnect board https://www.emeritus-solutions.com/papertape/fanuc/Pic16F13145FanucInterfac… https://www.emeritus-solutions.com/papertape/fanuc/Pic16F13145FanucInterfac… FWIW I usually use a Zynq to interface PTRs, this design was an exploration of the 16F13145's capabilities, serendipitously providing a "uart" on an EVB solution The PTRs run the capstan continuously, the pinch roller is engaged by the centre off switch on the front panel: Manual - feeds tape, but does not assert DataValid; Auto - feeds tape and asserts DataValid. The PIC outputs octets when DataValid is asserted. The pinch roller is engaged when Auto or Manual is selected. The Brake Clamp is engaged when the NO foot pedal is closed. The PT feed is friction, the reader is opto with LED illumination. The A02B-0047-C061 is compact https://www.emeritus-solutions.com/papertape/fanuc/A02B-0047-C061_Ptr_Front…, but may not come with a Fanuc interface card A20B-007-075D https://www.emeritus-solutions.com/papertape/fanuc/A20B-0007-075D_Ptr_Inter… (which you will need). The A13B-0070-B001 is a 6U 19" rack panel https://www.emeritus-solutions.com/papertape/fanuc/A13B-0070-B001_Ptr_Bin_F… typically the interface card is attached to this panel So, picks from eBay.com are: https://www.ebay.com/itm/126851010269 https://www.ebay.com/itm/393980423195 although I have no idea if the PSU is any more than an ornament https://www.ebay.com/itm/233194641467 or https://www.ebay.com/itm/304005388602 plus https://www.ebay.com/itm/184870581852 or https://www.ebay.com/itm/293557099779 or with a diy panel https://www.ebay.com/itm/224491588288 etc etc More than one set of bits may be required to eliminate squeaks, but the simple PTRs usu seem to work Also, https://www.ebay.com/itm/150974081687 is RtR and uses the same IO interface card as its lesser siblings - I'm (still) reverse engineering the push button and remote logic which is for CNC Gcode use cases https://www.ebay.com/itm/167311496458 is 2nd generation RtR and I have yet to make mine work ...; item zero is stw a (mechanically damaged) AC PSU ... HtH, Fanuc also made a PPR Punch Printer Reader with a serial (usu 4800) baud interface https://www.ebay.co.uk/itm/405256535393 This cookery makes serviceable PTRs out of inexpensive pre used readers - ten times cheaper than a PPR ? And of course my wiring sheet tells you how to hook up to your favorite hardware - game on ? Martin -----Original Message----- From: Mike Katz [mailto:bitwiz@12bitsbest.com] Sent: 11 April 2025 15:59 To: Martin Bishop <mjd.bishop(a)emeritus-solutions.com> Subject: Re: [cctalk] Paper Tape Reader Needed I'm intrigued... On 4/11/2025 5:54 AM, Martin Bishop wrote: > Mike > > If a clone of https://www.emeritus-solutions.com/papertape/fanuc/Pic16F13145FanucInterfac… would solve your problem I'm happy to share the cookery. > > With 60 Hz AC 300cps to a serial port (USB C); the 1/4" jack is for a foot pedal "hold". > > For US sources of readers see eg : https://www.ebay.com/sch/i.html?_nkw=fanuc+tape+reader - $50 to $3000 for the same thing ... > > Martin > > -----Original Message----- > From: Mike Katz via cctalk [mailto:cctalk@classiccmp.org] > Sent: 10 April 2025 17:10 > To: Tony Duell via cctalk <cctalk(a)classiccmp.org> > Cc: Mike Katz <bitwiz(a)12bitsbest.com> > Subject: [cctalk] Paper Tape Reader Needed > > I have acquired a bunch of PDP-8 and PDP-12 paper tapes and I need a reader so that I can archive them. > > Does anyone have a serial (RS-232) or USB reader or reader/punch that needs a good home or can be purchased for a reasonable price? > > Thank you, > > Mike > bitwiz(a)12bitsbest.com

1 year, 1 month

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Re: Why I am not worried about AI taking over the world!

by John Foust

At 12:39 PM 4/9/2025, Bill Gunshannon via cctalk wrote: >I'll continue to play with it but my initial reactions still stand. >No sign of intelligence and not ready for prime-time. What did you ask it to do? Exactly, I mean? When it didn't give you the answer you wanted, what did you say next? It would not surprise me if comp-sci departments now offer a major in writing GPT queries. Today's AI wranglers might be writing queries that range from a few words to a many pages of text. They're also having a conversation with it to refine their query. It's more than google.com circa 2005. Many of us spent years learning how to get better results from Google more often, after all. I don't have a problem with skepticism about it. Call it a parlor trick all day long, tell me it's not *truly* intelligent, but you should also examine it enough to get to the point where you'll say "that's truly an amazing and perhaps sometimes very useful parlor trick." - John

1 year, 1 month

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VCF East 2025 Post Event Survey

by Jeffrey Brace

Please take a few minutes to complete this anonymous survey about VCF East 2025. Your feedback is important and helps us in planning the next event. https://www.surveymonkey.com/r/YFLSKSW Thanks! Jeff Brace VCF East Showrunner

1 year, 1 month

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Altair BASIC Source Code released

by Murray McCullough

I wonder if this helped start the microcomputer revolution, OS-side, or was this a re-hash of what already was available? It's a historical event as per se but much more than that I'm not sure! Happy computing! Murray 🙂

1 year, 1 month

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Teletype in Cleveland

by Henry Bent

Not my listing, but I thought I would pass it on in case others were interested. https://nextdoor.com/for_sale_and_free/954bf8cc-66d6-4f41-a447-9c6aaae42ea3… -Henry

1 year, 1 month

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Why I am not worried about AI taking over the world!

by Bill Gunshannon

So, I am working on another fun project on my trusty old TRS-80's. I need the ability to do multi-line functions which TRS-80 BASIC does not support. But in hopes of finding something where someone added that capability in the distant past (there were lots of features added by various people over time) I decided to just try a Google Search. As we all know Google now begins results with an AI generated answer to your question. This is what I got: -------------------------------------------------------------------------- In TRS-80 BASIC, you can create multi-line functions (subroutines) using the DEF FN statement, allowing you to define a function that can perform a specific task and be called from different parts of your program. Here's how it works: DEF FN Statement: You use the DEF FN statement to define a function, followed by the function name (e.g., FNMyFunction), a set of parentheses for any arguments, and then the code that the function will execute. Example: 10 DEF FNC(X,Y) = X*X + Y*Y defines a function named FNC that takes two arguments (X and Y) and returns the sum of their squares. Function Call: To use the function, you simply call it by its name, passing in the necessary arguments. Example: 20 PRINT FNC(3,4) would print the value returned by the FNC function when called with arguments 3 and 4, which is 25. Multi-line Functions: You can extend the DEF FN statement to span multiple lines, allowing for more complex logic within the function. Example: Code 10 DEF FNC(X,Y) 20 LET TEMP = X * X 30 LET TEMP = TEMP + Y * Y 40 DEF FN END 50 PRINT FNC(3,4) This example defines a function that calculates the sum of squares of two numbers, but the calculation is broken down into multiple lines for readability. Key Points: Line Numbers: TRS-80 BASIC relies on line numbers, so make sure to use them appropriately when defining multi-line functions. Function Name: Function names must start with FN followed by a valid identifier (e.g., FNC, FNMyFunction). DEF FN END: You need to use DEF FN END to mark the end of the function definition, especially when using multi-line functions. Scope: Functions are defined within the scope of the program and are accessible from anywhere in the program. ----------------------------------------------------------------------- Which is both wrong and totally absurd. And I see things all the time about letting AI write your code for you. Does anyone actually trust AI to write code? bill

1 year, 1 month

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Re: Philips P3800 key lock swtch

by donald donaldwhittemore.com

Lishi tools can decode the bitting. Surprised the locksmith did not use them. Just need to identify the keyway style. https://covertinstruments.com/collections/lishi-tools

1 year, 1 month

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Re: Altair BASIC Source Code released

by Alan Frisbie

Bob Grabau <rgrabau1(a)verizon.net> write: > As my memory serves, there was a class given by the Southern > California Computer Society (SCCS) in which the disassembled the > Altair Basic (not sure if it was the 4k or 8k version) and used the > output of that disassembly for the class. There was a guy who had the > complete annotated (by the class) of the source as printed out copies > in his trunk, which he just handed out to anyone that asked for it. > This was somewhere between 1975-1978 (76-77 most likely) when I was a > member of SCCS. I was part of that disassembly effort and remember it well! I'm pretty sure I still have my copy of it stashed away here. It was a lot of fun. I had been a very early (1974) user of the 8080 at NCR, and this gave me a chance to contribute to the knowledge base. One thing I intend to do with this listing is find a piece of code I worked to disassemble, and read the comments. As I recall, it was part of some error handling. It consisted of a string of three-byte instructions that did nothing important, but if you jumped into the second byte of one, it would (as I recall) act as a two-byte instruction and load a register with an error code. After executing that 2/3 instruction, it fell into the remaining string of three-byte instructions which did nothing of interest. At the end, it would take the value that had been loaded earlier and use it. I was simultaneously impressed and appalled by this space-saving coding technique. I'm disappointed that two printer pages are combined into a single PDF page, as it makes it a bit difficult to read. Still, it is a great window into the minds of Bill, Paul, and Monte. Alan Frisbie

1 year, 1 month

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Re: Why I am not worried about AI taking over the world!

by John Foust

"Ancient BASIC dialects" seems like a rather small obscure domain and as they say, they're not making any more of them. I'd think that if you trained an AI on enough examples, they'd do much better. The BASIC language isn't that complex compared to modern languages where people are finding AI as a useful assistant, like it or not. Think of it like old-school "pair programming" that gives you a friend in your cube to talk to. - John

1 year, 1 month

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2026

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