- test-drb@ccmp.vtda.org - classiccmp.org

by joe.lang.0000＠gmail.com

I'm trying to find docs for monolithic systems 8009 board. multibus I, z80, RAM ROM 2 serial, FDC. I see references to the board online but no actual docs. I'm looking for information (schematic) for the on board interrupt logic and bus interface. I've figured out enough to get CP/M 2.2 running on it but things like interrupts,bus time out and arbitration are implemented in PALs and defy my attempts at reverse engineering. Even docs from another model (800X) may prove useful since similar logic may be used. thanks joe lang

11 years

2
3
0 0

cctech Digest, Vol 14, Issue 10

by clemc＠ccc.com

On Mon, Aug 10, 2015 at 1:00 PM, <cctech-request at classiccmp.org> wrote: > From: Brent Hilpert <hilpert at cs.ubc.ca> > > There was also AlgolW, supported on MTS. > > As MTS was being mentioned earlier I was going to ask if anyone knew > whether the AlgolW compiler was included in the available distribution. > ?The sources are available - they were googlable - send me a note off list and I can put together a tar image of what I have. FYI: It was written PL/360. I did some hacking on it under TSS years ago.? IIRC Wirth did AlgolW on the 360 at Stanford which was running one of the OS/360 flavors. CMU ported to TSS and Michigan to MTS. also check out: The Programming Languages Genealogy Project http://everything2.com/title/the+Programming+Languages+Genealogy+Project ?Clem?

11 years

3
2
0 0

And speaking of ALGOL

by jnc＠mercury.lcs.mit.edu

> From: Paul Koning > Every machine needs a fast memory system. CISC machines just as much, > after all the number of memory references per operation of a given kind > doesn't depend on the sort of CPU architecture you use. You're forgetting the memory bandwidth for the instruction fetching. RISC machines execute a stream of simple, low-level instructions, whereas CISC machines tend to do fewer, (semantically) higher-level operations - and in the process, use less memory bandwidth for instructions. To be tedious (sorry), for example, instead of of the RISC instruction sequence 'move register Ra to Rt1; add constant X to Rt1; move mem loc (Rt1) to Rt2; add Rn to Rt2; move Rt2 to mem loc (Rt1)', a CISC would just do 'add Rn to mem loc X[Ra]'. Same number of _data_ reads/writes, but a very different count of instruction fetches. The CISC tradeoff (fewer, slower, instructions) made sense 'back in the day', and not just for memory bandwidth - it made for more compact code, back when memory was in very short supply (by today's standards). Now, of course, a number of technological changes - primarily multi-level caches - have changed the 'sweet spot' for optimal instruction complexity, while keeping the memory bandwidth needed for instruction fetches down. Noel

11 years

2
1
0 0

And speaking of ALGOL

by mark.kahrs＠gmail.com

One could always implement a KDF9 emulator and then port Randall and Russell code (from the book). And r.e. ALGOL68, Peter Hibbard had some sort of ALGOL68 system working on the PDP11s at CMU I believe.

11 years

6
10
0 0

Fwd: sparc20 available in boston

by paulkoning＠comcast.net

Posting this for another NetBSD developer. Please contact him directly if interested; I don?t have any additional information. paul > Begin forwarded message: > > From: David Holland <dholland-developers at netbsd.org> > Subject: sparc20 available in boston > Date: August 11, 2015 at 2:05:41 PM EDT > > I have a sparc20 sitting in my office that I need to get rid of for > space reasons. Anyone in Boston want it? I do not have time to deal > with shipping it, but you're welcome to try to persuade someone else > around here to do that :-) > > It has a keyboard and mouse, and I think a framebuffer, but no > monitor. There are I think two or three cpu modules, though I vaguely > recall there being an issue with one of them. Dunno how much RAM it > has. > > Deadline is Friday, although if someone speaks up by then I might be > able to hold it until the end of the month. Otherwise it gets thrown > out... > > -- > David A. Holland > dholland at netbsd.org

11 years

1
0
0 0

Qbus split I&D?

by jnc＠mercury.lcs.mit.edu

> From: Johnny Billquist > The 11/34 that I played with did not have a product from Enable. ... > The product "my" 11/34 have came from Systime Thanks for chasing that down. Yes, that would explain the non-meshing memories! :-) > In addition, a few wires needs to be changed on the backplane, there is > a cable from a CPU card to the Systime card, and a few modifications > required on the 11/34 CPU itself. This all makes sense - if one can reach into the CPU, it's definitely plausible to have an upgrade which expands the size of the PARs (unlike the ENABLE board from Able). Noel

11 years

2
1
0 0

And speaking of ALGOL

by jnc＠mercury.lcs.mit.edu

> From: Chuck Guzis > Why all this DEC stuff about Algol? I probably started it; I just mentioned the PDP-11 one because a lot of people already have either 11's, or an emulator up and running. Noel

11 years

1
0
0 0

OT: Slow booting, was re: Booting an IBM MP 3000 S/390 System

by jnc＠mercury.lcs.mit.edu

> From: Chuck Guzis > Could it be that the presence of ECC registered SDRAM requires that > every memory location get written before boot-up can proceed? There's > 2GB of the stuff, so that could be the difference. I was going to suggest that, actually. Turning on ECC in the memory in a somewhat older HP minitower machine caused a long delay in booting while it cleared all the memory. Noel

11 years

1
0
0 0

DEC RX02-PA?

by ben＠bensinclair.com

I found this on eBay, and I'm not sure what it is: http://www.ebay.com/itm/VINTAGE-DIGITAL-RX02-COMPUTER-SYSTEM-2-FLOPPY-DRIVE… I haven't seen RX-02s in a case like this before, and some Googling doesn't seem to reveal much of anything. Does anyone know what this is exactly? Thanks! -- Ben Sinclair ben at bensinclair.com

11 years

11
21
0 0

SCSI Tape to TAP utility

by marc.verdiell＠gmail.com

Thanks Jay! Marc ---------------------------- From: Jay Jaeger <cube1 at charter.net> The link below is to a Google Drive folder with three files that I will leave up for a while: awstape.c - Read a SCSI tape, output in AWS format (Linux) awstoraw.c - Read an AWS file, output a raw byte stream awstosimh.c - Read an AWS file, output a SimH https://drive.google.com/folderview?id=0B2v4WRwISEQRfi1TWnlKU1hqUXphWVhpZ1FK OGFoVjRPVnppX1F2aUMwTUw0QkxSNEsyMjg&usp=sharing They are anything but elegant, but have gotten the job done for me. JRU --------------------------

11 years

1
0
0 0

Friendly reminder to any 5620 / BLIT owners...

by ian.finder＠gmail.com

The battery in the teletype DMD 5620 is mounted in a very fatal position, and does indeed leak, as I learned this weekend. If you have not removed it, I would get on that now. In fact, if you still have batteries in anything, you might be doing it wrong... ;) Cheers, - Ian -- Ian Finder (206) 395-MIPS ian.finder at gmail.com

11 years

3
3
0 0

SCSI Tape to TAP utility

by marc.verdiell＠gmail.com

Hey, I'll take the offer, I am interested in both. Marc > Jay Jaeger wrote: > If anyone is interested, I have code for a Linux SCSI tape to > AWSTAPE program, and a program that translates aws format to a raw > byte stream. Not sure if I have one that translates to the SimH .tap > format, though. GNU C. > Chuck Guzis wrote: > I've got a Linux utility to translate SIMH .tap to raw binary, if that's > interesting to anyone. I would have thought that such utilities existed > already.

11 years

3
3
0 0

PDP-12 Restoration at the RICM

by michael.99.thompson＠gmail.com

We found a shorted diode in one of the rectifiers in the +/-42VDC supply in the VR14 that was causing the main fuse to blow. The donor of the PDP-12 gave us a spare so that was an easy fix. We reinstalled the VR14 in the PDP-12 and ran the display diags. The VR14 display actually works! We found a open trimpot for the gain on the vertical flip-chip. We swapped the horizontal and vertical flip-chips, adjusted the gain trimpot, removed the flip-chip, and added a fixed resistor with the same value for now. The display when running the diags looks very nice and crisp. We booted LAP6-DIAL and could display a listing of the files on the tape on the VR14 monitor. After about 20 minutes of running nicely, the TC12 went back into the mode where it could not find blocks. Oh well, more debugging to do. -- Michael Thompson

11 years

1
0
0 0

Booting an IBM MP 3000 S/390 System

by marc.verdiell＠gmail.com

Wow. I'll never complain again that it takes too long to boot Windows...

11 years

28
61
0 0

Classic programming

by jnc＠mercury.lcs.mit.edu

> From: Eric Christopherson > people who like to program in languages or language implementations or > libraries that are no longer in common mainstream use? I prefer to write code under (effectively) V6 Unix; I find that I can get things working and done faster there than in any other environment. Of course, if one sticks to just the Standard I/O library, you can get more or less than same environment pretty much everywhere: Windows, Linux, etc. > From: Sean Conner > My current Holy Grail piece of software would be Synthesis OS---an > operating system written in assembly (in 1991) that can recompile and > specialize itself on the fly [6]---basically, a program can request and get > custom system calls to use. > ... > [6] http://valerieaurora.org/synthesis/SynthesisOS/ Wow. I had a look at that site: Very Very Very Cool. Is source still extant anywhere? (I know, I could email the creator...) Also, ISTR a post which talked about Guy Steele working on EMACS. I don't think that can be correct - Guy had, IIRC, departed MIT before I got to Tech Sq, and EMACS had just started being developed when I got there. As to who actually did do EMACS, it was a cast of characters, and I wasn't enough part of it to know who should be listed. RMS was, of course, primus inter pares, but there were others. E.g. I remember Gene Cicarelli did some stuff. There was this thing called IVORY which IIRC 'purified' TECO code so that it could be dumped out in a compressed form (for faster loading, execution, etc - it may have also been possible to have it read-only, and the page(s) shared between multiple EMACS instances, but my memory is foggy on this), and Gene did that. Noel

11 years

6
6
0 0

MTS

by lyndon＠orthanc.ca

There have been a few references to MTS over the past couple of months that led me to suspect people are running it under Hercules. I did some poking around a while back and managed to find some tape images (bitsaver, I think), and did some cursory reading of the release notes. I think there might be enough there to IPL and perform a basic installation, but what immediately caught my attention was the mention that sites had to purchase ASMH from IBM, which leads me to believe the public distributions don't contain an assembler. I cut my teeth on *real* computers on the U of Alberta's Amdahl running MTS, and I can't possibly imagine using it without an assembler. So my first question is: is anyone running MTS under Hercules from these public images? And if yes, question 2 is: which languages are included? One of the main reasons I would like to get MTS running would be to play around with the scheduler code. I remember some changes that were introduced circa 1981 that - I thought - destroyed the interactive response time of the system. E.g. APL went from being a joy to practically un-usable, IMO. I've always wanted to poke around in there and see if I couldn't fix it. And to get thoroughly esoteric and obscure, what are the odds that someone out there squirreled away an archive of SHOW:? from UQV-MTS? --lyndon

11 years

7
11
0 0

Adding a Hard Drive to an Original IBM PC Using a Raspberry Pi

by fozztexx＠fozztexx.com

One of my favorite old computers to tinker with is a rev B IBM PC. I recently moved it out into my living room to hopefully inspire me to mess with it more, but I still didn?t want to mess with having to put everything on 360k floppies. With all the slots occupied I had to find another solution for mass storage. Raspberry Pi to the rescue! I was able to use XTIDE and a Pi to emulate a hard drive over the RS232 port. All the details are here on my blog post: http://www.insentricity.com/a.cl/244 -- Follow me on twitter: @FozzTexx Check out my blog: http://insentricity.com

11 years

2
2
0 0

SCSI Tape to TAP utility

by cclist＠sydex.com

A couple of weeks ago, I offered to share the source and executable for a SCSI tape-to-SIMH .TAP file utility for MSDOS. To run it, you'll need an ASPI driver for your SCSI adapter. It was compiled using MSC 8.00C. Find it here: https://www.dropbox.com/s/x6qiudlpyitgxom/STP2T02.ZIP?dl=0 Enjoy, Chuck ------------------------------------------------------------- "The first thing we do, let's kill all the spammers."

11 years

10
20
0 0

FOR SALE: HP 700/92 green screen monitor

by shawn-gordon＠cox.net

Excellent condition, $100 plus shipping or best offer.

11 years

1
0
0 0

Classic programming

by jnc＠mercury.lcs.mit.edu

> From: Paul Koning > Algol 60, that is. It was used as the inspiration by just about > everything that followed I've just remembered that the Algol (probably Algol-60, but the manual doesn't say) interpreter used for the programming languages course at MIT was adapted from the Delphi (a homebrew PDP-11 OS used at MIT) version, to a version that would run under Unix V6. So it should be runnable under any PDP-11 emulator. I _think_ I have that on those backup tapes I'm trying to get read, so maybe someday (it's a pity none of that MIT Unix stuff seems to have escaped into preservation, at least, so far) it will be widely available. They had a BCPL compiler for the PDP-11 that ran under Unix, too. Ditto about 'on the tape'. > From: Phil Budne > Mostly I write SNOBOL4 throw away programs for textual transformations. Huh, that's what Regex-Replace is for! ;-) Noel

11 years

4
6
0 0

Apollo DN series HP root account

by wcn440＠gmail.com

I have a vintage apollo question... In the late 1980's when HP acquired Apollo Computer Inc, I recall there was an HP root account, that shipped with every new machine. In many cases this account was not removed. I recently acquired a DN3000 and to my amazement it was clean, and booted to an SR10.4 login prompt. Does anybody remember that HP account and password? Alternative cracks would be welcomed as well. Bill Newman

11 years

4
3
0 0

Classic programming

by echristopherson＠gmail.com

Is there a subset of this group for people who like to program in languages or language implementations or libraries that are no longer in common mainstream use? Or other groups for such a thing? -- Eric Christopherson

11 years

25
43
0 0

Classic programming

by jnc＠mercury.lcs.mit.edu

> From: Johnny Billquist > And one should not forget Algol. IIRC, Algol is mentioned in the paper I linked to. Of course, Algol's DNA is in pretty much every procedural language ever created since it was. > From: Andy Holt > (and, for that matter, PL/1 should probably be considered an unsung > inspiration for C as it was the implementation language for Multics > in which Bell labs was a partner and must have inspired at least > the name for Unix) The paper also mentions PL/I - IIRC, they (Ken, Dennis et al) had used it on Multics, and didn't like it. (Which I can understand!) I'm not sure there are any ideas from PL/I (specifically) which influenced C. Multics' influence on Unix is a very sizeable topic, which I won't derail into - it's an interest of mine, and I've been doing research on that; my hope is to do a paper on it at some point. The executive abstract is that the two extremes one hears ('Unix is derived from Multics'/'Unix is in fact a counter-reaction to Multics') aren't really accurate - the truth is in the middle. Noel

11 years

7
10
0 0

Booting an IBM MP 3000 S/390 Syste

by michael.99.thompson＠gmail.com

Date: Thu, 6 Aug 2015 18:43:53 +0100 > From: "Dave G4UGM" <dave.g4ugm at gmail.com> > Subject: RE: Booting an IBM MP 3000 S/390 System > > Actually I remember booting an IBM4381 from cold after we shut it down > over Christmas. Just pressing the Power button powered it up eventually, > but I am pretty sure it took nearly an hour to get to the IPL prompt. So it > did disk drives, then tape drives, then other bits and bobs. But when it > spun up the disks it brought them up one at a time so the startup surges > didn't trip the main breaker. The same with the tape drives. Then it > loaded the microcode into all the controllers. Then it booted the OS. As we > were running VM this last bit took a few seconds (I think). I do know if VM > crashed you screen logo frequently re-appeared before you had time to think. > > Dave Wade > G4UGM > I have done the same on a Honeywell mainframe. After powering up everything manually the only the mag tape and card reader I/O controllers had boot capability. Push the INIT and BOOT buttons and it would read and load tape controller microcode from mag tape, then read and load the disk controller microcode, then the processor's boot code, and then boot from disk. It took just seconds for the mag tape part. Getting the front end processors bootloaded, and getting online communications, timesharing, and batch processing up took a while. This system was capable of booting from binary punched cards. We used to try it periodically just to make sure that this capability worked. -- Michael Thompson

11 years

2
1
0 0

Guy Steele and Emacs - was Re: Classic programming

by jnc＠mercury.lcs.mit.edu

> From: Toby Thain > Peter Siebel's "Coders at Work" features a chapter/interview with > Steele: Ah, thanks for pointing that out; I do have that volume, but I guess I didn't read Steele's chapter. > "So I worked seriously on the implementation of Emacs probably for only > about four or six weeks." That's probably why I didn't know of it - blink and you missed it! :-) Noel

11 years

1
0
0 0

PDP-12 Restoration at the RICM

by michael.99.thompson＠gmail.com

When we first powered up the PDP-12 the main fuse for the VR12 display blew. A replacement fuse did the same. We thought that the brown goo in the bottom of the chassis had leaked from the high-voltage power supply, and the high-voltage power supply is directly connected to the input, so that was the first suspect. We bench tested the high-voltage power supply using a Variac on the input. With a 10VAC input there was no output at all. Increasing the input voltage did not change the missing output voltage. I hate to mention this but... The two capacitors in the voltage-doubler circuit are connected in series between the output lead and ground. We connected a current limited lab power supply to the output lead and ground and slowly increased the voltage while watching the current draw. With the voltage stable the current draw was a few microamps. We increased the output voltage of the power supply to the 64VDC max, disconnected the power supply, and measured the voltage across the caps. It very slowly decreased, so maybe the caps were OK. We reconnected the Variac to the input and with 10VAC the high-voltage power supply had a 1000VDC output. We put 10x 500kOhm resistors in series across the output and increased the Variac voltage. By measuring the voltage across one resistor we could see that the output was more than 10,000VDC. The resistors started smoking so we knew that we had a lot of high-voltage available. So, once again the magic of reforming capacitors saves another piece of equipment. -- Michael Thompson

11 years

2
1
0 0

Qbus split I&D?

by jnc＠mercury.lcs.mit.edu

> From: Johnny Billquist > All I can say is that I did a number of RSX SYSGENs on that 11/34, and > it truly looked just like an 11/24 from a software point of view. The thing that I wonder about it, for that to be true, is something that someone (sorry, to lazy to look in the archive to give proper credit) pointed out, which is that that CPU is only two boards, and the memory management, including the PARs, is built into one of them. So how could one extend a PAR >from 12 bits to 16, when there's already 12 bits buried deep inside the CPU? That's the part that I can't work out... > I'm hoping that Update ... still have the documentation around. You and me both! :-) I have this dream of one day having an 11/45, with the Enable and the optional cache. Now that would be a sweeet machine: most of the capability of an 11/70, but a lot less power draw. But I'd need the documentation to see how to connect it up! :-) > Every time this comes up I really want to go searching for manuals... > :-) Please do! :-) Noel

11 years

12
26
0 0

Qbus split I&D?

by jnc＠mercury.lcs.mit.edu

> From: Johnny Billquist > One more thing to check this summer... OK, if you can, that would really be great; if either i) it's still together, or ii) there are pictures, it would fill some of the key knowledge gaps. In particular, i) what kind of backplane is it plugged into, and ii) what is the UNIBUS edge connector on the card connected to... Noel

11 years

2
1
0 0

Classic programming

by jnc＠mercury.lcs.mit.edu

> From: Kip Koon > I have often wondered what the inspiration for the C Language was. BCPL > -> MCPL -> B -> c, quite an interesting list of languages. I don't think MCPL is in there; B was directly inspired by BCPL. See Dennis M. Ritchie, "The Development of the C Language": http://www.bell-labs.com/usr/dmr/www/chist.html I got the impression from the previous discussion that MCPL was a later branch. Noel

11 years

7
7
0 0

VAX4000/300 MNS7.3 isntallation from CDROM

by holm＠freibergnet.de

Hi, I've got an VAX4000/300 eqipped with an TK70, 2x RF31, 1xRF71 disks, and an CQD-200/TM. I've connected an toshiba Xm5701 drive to the SCSI Bus and the machine sses it as DUA3. I have a VMS7.3 CDROM and want to install it on one of the disks. I've read some documents on HPs website but it isn't clear to me how to boot the cdrom correctly, there is root 1 mentioned. What bootflag must entered, B/R5:10000000? ..in the case w/o the R5:10000000 I get a $ Promt finally (here I habe to read further). With the bootflag the System is complaining that dua3 is write protected (it is the cdrom)... What's the correct way to install VMS on that machine? Regards, Holm -- Technik Service u. Handel Tiffe, www.tsht.de, Holm Tiffe, Freiberger Stra?e 42, 09600 Obersch?na, USt-Id: DE253710583 www.tsht.de, info at tsht.de, Fax +49 3731 74200, Mobil: 0172 8790 741

11 years

6
26
0 0

OT: Slow booting, was re: Booting an IBM MP 3000 S/390 System

by seefriek＠gmail.com

Supermicros (and to a similar degree Tyan) are mostly in the "server class" of motherboards. That apparently means they put a *lot* of self-test code in there somewhere. I've had literally thousands of Supermicro machines of a dozen different types at various times, and they all took an inordinate amount of time to decide to think about booting no matter what (all auto-detect turned off, quickboot on, inboard SCSI disabled). I got used to it, because quality-wise it was worth the wait.

11 years

1
0
0 0

PDP-12 at the RICM (Michael Thompson)

by michael.99.thompson＠gmail.com

Yesterday we started disassembling the CRT from the VR12. We picked out the silicone that attached the metal bezel to the front of the CRT. The exposed PVA was about 1/8" thick so we picked at the edges to remove as much as possible. We found that the shield was actually loose and were able to remove it without the usual heating or using nasty chemicals. Today we are forming a sheet of 0.093" LEXAN to replace the PVA. It should be a much better implosion shield than the original PVA. Picture here: http://www.ricomputermuseum.org/_/rsrc/1439041136242/Home/equipment/dec-pdp… <http://www.linkedin.com/redir/redirect?url=http%3A%2F%2Fwww%2Ericomputermus…> We tested the high-voltage power supply and it works well. Maybe we can start reassembling and debugging the VR14 this afternoon. -- Michael Thompson

11 years

1
0
0 0

IBM panel... warning

by tmfdmike＠gmail.com

Some of you may remember an IBM System/370 Model 155 panel on eBay a couple of months ago. Something recently prompted me to look that auction up again, and after reading this I decided to warn the list in case it shows up again. The buyer left the following feedback: SCAM! didnt sell 4 enough $, wanted $3000 more outside of eBay after I paid him! IBM System 370 Mainframe front panel (#181771383679)US $727.00 Be warned. Mike http://www.corestore.org 'No greater love hath a man than he lay down his life for his brother. Not for millions, not for glory, not for fame. For one person, in the dark, where no one will ever know or see.'

11 years

1
0
0 0

Classic programming

by jnc＠mercury.lcs.mit.edu

> From: Eric Christopherson > I should check TECO out some day. Only if you want to damage your brain. Have you ever _actually looked_ at any TECO code? If not, try this: http://scienceblogs.com/goodmath/2006/09/22/worlds-greatest-pathological-l-… (It is not without reason that it is described as 'looking like line noise'.) Noel

11 years

2
1
0 0

Unidentified chip -- Spoiler for HP 1260-0339

by ard＠p850ug1.demon.co.uk

> As a total aside, on some HP boards there is a 16 pin DIL package with the part number 1260-0339. > Any ideas what that chip is? What chip? Amazingly there is nothing inside that 16pin DIL package. No silicon chip, no thick-film resistor network, nothing. It is just a package with the pins. The purpose of it? It's a connector (!) to fit one of those IC test clips on to monitor various signals. -tony

11 years

8
12
0 0

NOS!!! Compugraphic, (2) Computer Automation Naked Mini, (2)Motorola M-4408

by useddec＠gmail.com

All unused! Please contact me off list if interested. Located in zip 61853

11 years

1
0
0 0

OT: SNA was RE: Booting an IBM MP 3000 S/390 System

by dave.g4ugm＠gmail.com

> -----Original Message----- > From: cctalk [mailto:cctalk-bounces at classiccmp.org] On Behalf Of JP Hindin > Sent: 06 August 2015 19:07 > To: General Discussion: On-Topic and Off-Topic Posts > <cctalk at classiccmp.org> > Subject: RE: Booting an IBM MP 3000 S/390 System > > > > On Thu, 6 Aug 2015, Dave G4UGM wrote: > >> Booting an old CDC 6000-series machine meant mounting a "deadstart" > >> tape, pushing the button just below the screens on the DD60, entering > >> or editing the equipment status table, then going out for a smoke > >> (not me) or a cup of coffee, while the system copied the deadstart tape > to disk. > >> The next prompt was to enter the date and time. > >> > >> People are too impatient today. > >> > >> --Chuck > > > > Actually I remember booting an IBM4381 from cold after we shut it down > over Christmas. Just pressing the Power button powered it up eventually, > but I am pretty sure it took nearly an hour to get to the IPL prompt. So it did > disk drives, then tape drives, then other bits and bobs. But when it spun up > the disks it brought them up one at a time so the startup surges didn't trip > the main breaker. The same with the tape drives. Then it loaded the > microcode into all the controllers. Then it booted the OS. As we were running > VM this last bit took a few seconds (I think). I do know if VM crashed you > screen logo frequently re-appeared before you had time to think. > > Spinning off on this tangent, when I was learning how to fire up my Sun E10k > I didn't realise it took so ruddy long for the SSP and the E10k to speak to each > other. > So I was constantly asking the SSP for the E10k's power status (to see if they > were communicating) and being told the SSP "wasn't the master". > > I'd powered things up repeatedly and made all sorts of changes to the SSP > config and just couldn't figure out what wasn't working. So one day I'm > messing with it again and I'd walked over to the other side of the shop for a > manual and gotten distracted and maybe ten minuted passed and all of a > sudden all of the blowers dropped RPM and evened out. The SSP and E10k > had finally finished their secret masonic handshake and the SSP did the > equivalent of "Hey, dude, it's not 7000 degrees in here, you can chillax now". > > "People are too impatient today" -- Chuck G > > True enough. I just didn't know enough to know I should be patient. Excuse me if this isn't Exactly right, but I seem to recall some on in IBM saying that Thomas Watson Jr got a phone call one day. It went... TWJ: Thomas Watson here CLR: Is that Thomas Watson Jnr. TWJ: Yes CLR: and you are the head of IBM TWJ: Yes CLR and you first name is Thomas TWJ: yes CLR: and you are the head of IBM TWJ: yes CLE: and you are in your office TWJ: yes, but what do you want CLR: Just thought I would show what it is like trying set up and SNA session. Bye... > > - JP

11 years

2
2
0 0

Fwd: ROLM CBX 8000 System Service Manual Vol. 2 Scans Released!

by scaron＠umich.edu

Cross-post from the Collectors Network list that may be of interest to folks here. If anyone out there happens to have an old copy of Vol. 1 of the CBX 8000 System Service Manual, or might know an old ROLMan (or ROLwoMan) who might have same, I surely would appreciate the opportunity to digitize it! These are eventually going to be submitted to the Telephone Collectors International Library but it's certainly okay to take a copy for Bitsavers as well, if so desired. Best, Sean ---------- Forwarded message ---------- From: Sean Caron <scaron at umich.edu> Date: Thu, Aug 6, 2015 at 6:17 PM Subject: ROLM CBX 8000 System Service Manual Vol. 2 Scans Released! To: Voice Over IP Tandem for Analog Switches <voip at ckts.info>, Sean Caron < scaron at umich.edu> Hi all, I finally got around to digitizing the copy of the second volume of the ROLM CBX 8000 System Service Manual that I had received courtesy of Dennis Hock. I've got the scans sitting on my personal site for now until I figure out the process for getting them submitted to the TCI Library. Everyone is welcome to peruse: http://wildflower.diablonet.net/~scaron/pdf/ROLM/ Please note that Comcast has been kind of dodgy at my place recently, so the quality of the connection may fade in and out a little bit. As this document is very large (perhaps around 1,000 pages) the scans were done mostly by machine. I dumped a chapter at a time into a Konica Bizhub 300 series MFP and scanned in double-sided mode at 300 DPI. I've cursorily reviewed them and it looks like the Bizhub did a pretty nice job of scanning ... there's a little bit of white space due to not all pages being double sided, and due to the fold-outs, but all the information is there! Thanks so much, Dennis, for loaning the manual to me and I'm sorry it took me so long to get to it. I'll try to have the original back in the mail heading your way within the week. Let's hope this will stir someone to dig up an old Vol. 1 on which I can do the same :O Cheers! Sean

11 years

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OT RE: Saved DEC kit

by jwest＠classiccmp.org

Tony wrote (re: 25kg)... ---- Its about half the weight of many minicomputer bits (I think an RK05 drive is about 50kg for example). ---- I cry DEC-bias, using an RK05 as your UOM ;) For HP, a bare 7906 drive is 75kg (165#), and with controller, power supply, and desk side rack that only holds the one drive - 154kg (340#). A 7970 is 59kg (130#). A bare 2113 cpu is 30kg (65#). Funny how I have those weights right at the top of my head ;) So I'd say that 25kg is more like 1/3 of many minicomputer bits *grin* J

11 years

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Unidentified chip

by jnc＠mercury.lcs.mit.edu

So, I took Tony's advice (about parts) to heart, and have been stocking up on all sorts of things. (Ironically, I now have a _far_ better supply of parts that I had access to, back in the day, at LCS at MIT! But that's a rant for another day.) As part of that, I've bought up a number of IC collections, to build up a stock of 74xxx parts in various families (S, LS, etc). Along with them, I have acquired a lot of stuff I don't need (e.g. CMOS parts), and at some point I'll offer them here, for trade, for people who do have a use for them. (The PDP-11 systems I'm interested in basically don't use them.) As I've finished sorting and filing all that stuff, I'm left with a few things I can't ID. The most prolific one (I think I have about 6 tubes full :-) is something I'd appreciate a hand with: it might be some super-rare chip that people would love to find, or something. It's a 16-pin DIP, with the following on it (in three separate lines): "1028126", "D39315-A", and "CS9336P". The first number looks like the numbers I've seen on a couple of other un-identified chips, made by TRW. (I hope they aren't something classified I'm not even supposed to have! :-) Anyone have any idea what these things are? Thanks! Noel

11 years

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VT340, VT340+, and other monitor repairs

by useddec＠gmail.com

Anyone interested in repairing some monitors in exchange for DEC gear or possible cash? sorry, US only because of shipping. Please contact me off list if you are interested. Thanks, Paul

11 years

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Was there 3rd party DEC PRO CTI boards?

by pontus＠Update.UU.SE

Hi Out of curiousity, since I now have a DEC PRO380. Was there any third party manufacturer of CTI expansion boards? Regards, Pontus.

11 years

2
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Pertec Tape Drive Interface Musings

by marc.verdiell＠gmail.com

>If you're willing to run MSDOS with an appropriate ASPI driver, >I can send you a utility that I know works []You're >welcome to the source code. >--Chuck Chuck, Could you share your DOS code with me too? I just assembled the hardware for that: a self loading HP88780B SCSI-1 9-track Tape Drive, a vintage DolchPac 65 PC that can multi boot XP, Win98 and DOS fitted with an old SCSI-1 card. And I am reading the SCSI protocol book in the evenings ;-). Your DOS SCSI tape software and source would give me a prodigious head start... I also have Pertec-interfaced Overland Data tape drive, that will be step 2. This is a more straightforward interface. And an HP-IB interfaced HP7970E tape drive waiting in the wings. Marc

11 years

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Looking for AMI S4008 or MOSTEK MK4008

by nw＠retroComputingTasmania.com

On Wed, Aug 5, 2015 at 11:32 AM, Bill Sudbrink <wh.sudbrink at verizon.net> wrote: > Subject pretty much says it all, except that I need the > ceramic package with the metal lid. Like this? http://www.ebay.com/itm/MK4008P-2-MOSTEK-16-Pin-GOLD-PURPLE-DIP-Vintage-MK4…

11 years

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Looking for AMI S4008 or MOSTEK MK4008

by hilpert＠cs.ubc.ca

On 2015-Aug-04, at 6:32 PM, Bill Sudbrink wrote: > Subject pretty much says it all, except that I need the > ceramic package with the metal lid. Not that it's a help, but I have a Wang calculator that uses an array of MK4008's. Ceramic & lidded but the gold-plated pins rotted on one or two of them - recovered by soldering new pins onto the side. Could do with spares but they're not common. Would your interest in the specific form be for image sensor experiments?

11 years

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Pertec Tape Drive Interface Musings

by nf6x＠nf6x.net

I was looking at a couple of documents describing the Pertec tape interface; the manual for my Kennedy 9610 tape drive, and a nice reference by a fellow with a rather familiar name: http://www.sydex.com/pertec.html According to my Kennedy manual, issuing a read command causes the drive to return one block of data. I can see how that would be used in block-oriented applications in which blocks may be randomly read, written and re-written on the tape. But most of my magtape experience has been using the tapes in a streaming mode, such as when reading/writing one or more tar archives separated by file marks. When writing a tar archive on a magtape from a Unix system, is the archive written as a sequence of fixed-size blocks? Or is the entire tar archive effectively written as one continuous block which must be streamed with no repositioning? I'm curious because I'm daydreaming about how to build a tape drive interface controller, and I wonder whether it might need to potentially stream an entire tape in one go vs. being able to safely assume some maximal block size. -- Mark J. Blair, NF6X <nf6x at nf6x.net> http://www.nf6x.net/

11 years

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Looking for AMI S4008 or MOSTEK MK4008

by wh.sudbrink＠verizon.net

Subject pretty much says it all, except that I need the ceramic package with the metal lid. Thanks, Bill S.

11 years

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Tandy / Corvus Network

by snhirsch＠gmail.com

I've been given a small board that I believe is a Corvus Omninet adapter for TRS-80 Mod 3 or 4. I _think_ it's intended to support a product called "Network 4" that appears on a few old Tandy price lists and ad brochures. I'd love to find out more about the environment it's intended for and, if possible, get my hands on the technical documentation and system software. Is this familiar to anyone on the list? Steve --

11 years

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Amstrad CPC 464 acquisition

by terry＠webweavers.co.nz

I got this model a few months ago and have written a few words about the process. For those interested... http://www.classic-computers.org.nz/blog/2015-08-03-acquiring-amstrads.htm Terry (Tez)

11 years

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AM Varityper (phototypesetter)

by cclist＠sydex.com

I don't know how many of you were familiar with the Addressograph-Multigraph (AM) Varityper phototypesetting systems. Basically small computers with floppy drives and a (very nice) terminal--and a big box that held quite a number of photo "font" disks. Basically worked by shining a light through a specific disk and character onto light-sensitive paper. Produced gorgeous print ready copy. Compugraphic and Mergenthaler had similar systems and I think there were also several other competitors as well. At any rate, a pile of 8" HS floppies will be landing here in the near future. Does anyone have any leads on Varityper service manuals or anything might help me with the task of figuring out what on the disks? (The disks themselves do not come from a country that uses the Latin alphabet). Thanks for any leads... --Chuck ------------------------------------------------------------- "The first thing we do, let's kill all the spammers."

11 years

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Pertec Tape Drive Interface Musings

by jnc＠mercury.lcs.mit.edu

> From: Chuck Guzis > BTW, what do you use to read UNIX v7 tar files? Linux/BSD modern tar > seem not to like the old archive format I have a very slightly hacked version of the V7 tar, which runs under Windows (under Cygwin). It read all the older TAR files which the newer TARs barfed on. Is that of any use to you? Noel

11 years

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Unusual stuff inside computers

by rickb＠bensene.com

A faded semi-nude 4x6 photo of a woman on a beach inside an IBM PC-XT that I found in a thrift shop many years ago. How or why it was in there is anyone's guess. -Rick

11 years

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Unusual stuff inside computers

by vlad.stamate＠gmail.com

Hi, I recently got a very nice HP 9816 with a 9121 drive unit from Earl Baugh (thanks Earl!). The computer worked fine but the primary drive of the 9121 refused to read the disk and made a continuous beating noise. After I cleaned it on the outside I opened it to see what is wrong with it. And I found this piece inside the drive itself: http://imgur.com/dlqOexX (floppy added for size comparison). After carefully removing it, the drive actually worked like a charm and I was able to boot from it. I was pleasantly impressed that the drive head has not been damaged bumping in the leather piece all the time. I am not sure how that got there, I assume a child pushed it in by mistake? I am not sure what it is either, the leather triangles sewn together by hand it seem. What other strange pieces did you find when you opened up classic computers? Vlad.

11 years

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SPARCClassic won't boot cdrom

by michael.99.thompson＠gmail.com

> From: Benjamin Huntsman <BHuntsman at mail2.cu-portland.edu> > Subject: SPARCClassic won't boot cdrom > > Hi all! > I recently acquired a SPARCclassic, which is my first bit of Sun > hardware. Having an awful time getting it to boot from the CD-ROM. I have > tried a bunch of different terminators and several different cables, but > whenever I try to boot I get this: > > ok boot cdrom -s > Boot device: /iommu/sbus/espdma at 4,8400000/esp at 4,8800000/sd at 6,0:d File > and args: -s > The SCSI bus is hung. Perhaps an external device is turned off. > > Any ideas as to what might be wrong here? The thing does not seem to > send any commands to the CD-ROM, as the LED never comes on and I don't hear > it doing anything... > > Thanks! > > -Ben > The terminator on the end of the SCSI bus needs to be powered. Without power on the terminator the bus will hang. Sometimes the power comes from the SPARC through the SCSI cable, but not all SCSI cables pass the power. Sometimes there is a jumper or switch on the last drive to enable SCSI terminator power. -- Michael Thompson

11 years

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This Hobby Is Actually Useful!

by robert.jarratt＠ntlworld.com

Today I was able to repair the LCD monitor (admittedly a cheap one) on my son's computer by replacing some of the electrolytic capacitors. Had I not got into collecting and restoring (sometimes) old DEC machines, I would not have had the ESR meter, the de-soldering and soldering equipment, suitable capacitors and sufficient knowledge (generously provided by many on this list) to do the job. Of course, compared to the things that many people on this list do, it is hardly a major achievement. But this hobby has now saved me from throwing away an old monitor and having to buy a new one. I suppose I now have at least some justification in the eyes of She Who Must Be Obeyed for continuing with this hobby J Regards Rob PS A related question. I struggled somewhat with the Weller Magnastat No. 8 tip, when trying to solder leads to the ground plane, I could not get the solder to stay molten very long. I was using lead-free solder, its melting point is much lower than the temperature which a No. 8 tip reaches. The iron is 50W. Clearly the ground plane was taking heat away, but is it a problem with the tip not being hot enough, the iron not powerful enough, or perhaps some operator error?

11 years

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paging mouse (rodents/montreal)

by jwest＠classiccmp.org

Sorry for the public post, can't get through privately. But oddly, the list seems to make it through. Very strange. Mouse, tried sending you a few replies, but your mail server sends rejections back from your MX host. Any chance you could whitelist the classiccmp.org server IP? Best, J

11 years

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Printer manuals that must go!

by auringer＠tds.net

Good morning all! I have the following printer manuals that I must get out of my space. If you want any of them enough to make it worth my while to ship them, let me know soon. They will be out of here by next Monday, one way or another. Shipping from Madison, WI 53714. Comrex ComRiterIIE User's Guide Gemini-10X/15X Users Manual Citizen MSP-40/45 User's Manual Wespergroup Model DLP-1132 Printer Controller User's Manual digital Letterwriter 100 Operator Guide Dataproducts Model 9030/9040 Printers Operating Guide Fujitsu M304X Series Line Printer Operator's Guide HP 7580B, 7585B, and 7586B Drafting Plotters Interfacing and Programming Manual HP 7580B, 7585B, and 7586B Drafting Plotters Interfacing and Operator's Manual Mannesmann Tally Spirit-80 Computer Printer Operator's manual Star Micronics radix-10 PC radix-15 PC User's Manual Panasonic KX-P3151 Daisy Wheel Printer Operating Instructions -Jon

11 years

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PDP-12 at the RICM (Michael Thompson)

by michael.99.thompson＠gmail.com

With a lot of help from Dave Gesswein and Warren Stearns we were able to get the MARK12 PDP-12 tape formatting program off a LINCtape and int paper tape format. Running it showed that a diode on the field-0 core stack had failed during the week making memory in the range of 4000-5000 unusable. Fortunately we had a spare core memory stack so we were running again in a few minutes. We have traced and replaced diodes on core stacks before, so we will fix the broken core stack. We were able to format a LINCtape, but running it without a video display was a little challenging. The tape diags work better with the reformatted LINCtapes, but still not perfectly. It looks like there is an issue in the selection logic in the TU56. That should not be difficult to debug and fix. We booted LAPS6-DIAL from LINCtape. The VT14 display is not working yet, so we were driving blind. We could see some fuzzy characters displayed on an oscilloscope so we could see that our typing was actually getting handled by the editor. We tried three different oscilloscopes, but none have an intensity or blanking input so the display was not readable. We couldn't find any documentation for booting OS/12 from LINCtape, so Warren looked through an octal dump and found that block zero is the boot block, just like OS/8. The OS/12 boot block starts at 0020 like many LINC programs. Since this uses the serial console we were able to interact with the OS normally. This is the first time in 24 years that an OS has been run on this system. -- Michael Thompson

11 years

3
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diagnosing an Intel Series II MDS monitor failure

by spacewar＠gmail.com

A few weeks ago, while I was testing a spare IPB-80 CPU card in an Intel Series II MDS, the monitor stopped working, with the raster collapsing to a very bright dot in the center of the screen. I hit the power switch and pulled the line plug immediately, but the dot persisted for several minutes, only gradually dimming. I just started investigating it. With the monitor cable unplugged from the IOC board, the +15V DC at the IOC connector reads 0.74V. Of the two DC power supplies described in the service manual, this MDS uses the Power One. The +15V rail uses a separate transformer winding, a 723C regulator, a house-marked (12500-4) NPN pass transistor, and a zener and SCR crowbar. The 0.74V makes me think the crowbar has tripped and the 723 regulator is current limiting. Nothing else in the MDS uses the +15V supply. I was a bit lucky that this particular MDS used "method A" of installing the monitor, which makes it easier to remove. Once the metal shield is removed, the label was visible. It is a Ball Electronic Displays TV-120 monitor, which is a common enough model that it was easy to find the service manual online. I'll test the monitor on a lab power supply to see if it's drawing too much current. I may kludge up Rich Ottosen's PIC-based TV test pattern generator on a breadboard.

11 years

5
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Front Panel Update

by rodsmallwood52＠btinternet.com

Hi Guys The drawings for pdp8/e (A), pdp8/e (B), pdp8/f and pdp8/m have now gone to the silkscreeners for checking and costing. I'll let you all know when they are available. Those who chose to prepay but to wait for the version they needed will go out first. One issue I need to clear up. Are PDP-8/i and pdp-8/l thats (i) and (l) the same due to font ambiguity or different? For the 8/e pair I had a scan (ie done with a scanner) to work with. The /f and /m look fine but I'm very fussy about being spot on. Photos help but the sphereical abberation due to a round lens trying to photograph a square object is a problem. This together with the fact that photos are never taken at right angles to and lined up with the centre of the panel make it difficult to be absolutely shure Is there anybody there that has an /f or /m panel and a big enough scanner. Or else I'd be happy to do a new for old on a scrap /f /m panel that is still readable Rod Smallwood

11 years

2
2
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Inverse Assembler for HP10343B SCSI Bus Preprocessor

by marc.verdiell＠gmail.com

Anyone has the Inverse Assembly and Logic Analyzer setup files that should go with the HP 10343B SCSI bus pre-processor? Another one that I wasn't able to find online. Marc

11 years

1
0
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SPARCClassic won't boot cdrom

by BHuntsman＠mail2.cu-portland.edu

Hi all! I recently acquired a SPARCclassic, which is my first bit of Sun hardware. Having an awful time getting it to boot from the CD-ROM. I have tried a bunch of different terminators and several different cables, but whenever I try to boot I get this: ok boot cdrom -s Boot device: /iommu/sbus/espdma at 4,8400000/esp at 4,8800000/sd at 6,0:d File and args: -s The SCSI bus is hung. Perhaps an external device is turned off. Any ideas as to what might be wrong here? The thing does not seem to send any commands to the CD-ROM, as the LED never comes on and I don't hear it doing anything... Thanks! -Ben

11 years

8
8
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PDP-12 at the RICM (Michael Thompson)

by COURYHOUSE＠aol.com

Congrats Michael! "This is the first time in 24 years that an OS has been run on this system." Ed# and crew at smecc.org In a message dated 8/2/2015 7:20:02 A.M. US Mountain Standard Time, michael.99.thompson at gmail.com writes: With a lot of help from Dave Gesswein and Warren Stearns we were able to get the MARK12 PDP-12 tape formatting program off a LINCtape and int paper tape format. Running it showed that a diode on the field-0 core stack had failed during the week making memory in the range of 4000-5000 unusable. Fortunately we had a spare core memory stack so we were running again in a few minutes. We have traced and replaced diodes on core stacks before, so we will fix the broken core stack. We were able to format a LINCtape, but running it without a video display was a little challenging. The tape diags work better with the reformatted LINCtapes, but still not perfectly. It looks like there is an issue in the selection logic in the TU56. That should not be difficult to debug and fix. We booted LAPS6-DIAL from LINCtape. The VT14 display is not working yet, so we were driving blind. We could see some fuzzy characters displayed on an oscilloscope so we could see that our typing was actually getting handled by the editor. We tried three different oscilloscopes, but none have an intensity or blanking input so the display was not readable. We couldn't find any documentation for booting OS/12 from LINCtape, so Warren looked through an octal dump and found that block zero is the boot block, just like OS/8. The OS/12 boot block starts at 0020 like many LINC programs. Since this uses the serial console we were able to interact with the OS normally. This is the first time in 24 years that an OS has been run on this system. -- Michael Thompson

11 years

1
0
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Saved DEC kit

by shadoooo＠gmail.com

Hello Adrian, how are you? Maybe you still have the SDI disks aside for me? Any time to ship them to me? Thanks in advance! Andrea

11 years

1
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diagnosing an Intel Series II MDS monitor failure

by cube1＠charter.net

Sounds just like the supply on my Altos. What a pain. Eric Smith <spacewar at gmail.com> wrote: >I previously wrote about the monitor of my Intel Series II MDS going >out, which was because the +15V DC supply tripped the crowbar. The >voltage adjust was all the way to the minimum, and the voltage was >still about 17.4V with no load, and trips the crowbar with even a >small load. I think someone previously encountered this problem and >adjusted the pot rather than fixing it, and the problem has gotten >worse since. > >The root cause of the failure appears to be that the internal voltage >reference of the uA723, which is specified as 7.15V ?0.35V, is now >9.4V. The uA723 needs to be replaced. The uA723 is still readily >available, but due to the construction of the power supply, replacing >it is relatively difficult. Just probing the pins of the chip was a >challenge. The pass transistors are mounted to 1/8 inch aluminum >plate, but the pins are soldered into rivets in the single-sided PCB, >entering from the etch side (which is closest to the aluminum), so >they will have to be desoldered to get at the etch side to replace the >723. I considered just cutting the pins of the 723 and soldering >another (or a socket) onto it from the component side, but pins 1-7 of >the 723 are right next to a big axial electrolytic so there's no way I >can solder that side. Input and output wires to the board are soldered >into single-pin cup thingies on two opposite edges of the board, so I >can't even get the board into an orientation suitable for working on >it without desoldering or cutting some of the wires. > >I haven't bench-tested the monitor, because I haven't kludged up a >suitable signal source yet, but I don't think there's anything wrong >with it.

11 years

1
0
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Reforming capacitors (technical description, not politics)

by spacewar＠gmail.com

Some people seem to think that "reforming" an aluminum electrolytic capacitor is some kind of cheat, akin to zapping NiCd cells or rejuvenating CRTs. Actually reforming is the same electrochemical process that the manufacturer uses to "form" the capacitor in the first place, building up the aluminum oxide layer, before the sheet is rolled into cylindrical form. The manufacturer typically uses a forming voltage higher than the rated voltage, from 135% to 200%, to provide margin for shelf life. When the capacitor goes unused for an extended time (shelf life), the oxide layer gradually breaks down, increasing the capacitor's leakage current and reducing the effective usable voltage of the capacitor, which is proportional to the minimum oxide thickness. If the oxide has developed spots that are too thin for the applied voltage, it may be damaged ("punch-through") when that voltage is applied. Punch-through tends to be a runaway process, so even a small amount of punch-through usually completely ruins the capacitor. Reforming the capacitor by applying current-limited power rebuilds the oxide layer to prevent this type of damage, and to reduce the leakage current back to within the specifications. The current limiting is what prevents the reformation process from causing punch-through and damaging the capacitor. Many of the capacitor vendors actually publish recommendations for reforming their capacitors. See for example information on manufacture on pages 13-14 and a brief recommendation of reforming procedure on page of 17 of Kemet publication F3304 dated June 2009: http://www.kemet.com/ProductCatalog%20Documents/F3304.pdf Also pages 2-4 on manufacture and page 16 on "recondition" (reform) of "CDE Aluminum Electrolytic Capacitor Application Guide": http://www.cde.com/resources/catalogs/AEappGUIDE.pdf Also pages 1-5 of Nichicon "General Description of Aluminum Electrolytic Capacitors": http://www.nichicon.co.jp/english/products/pdf/aluminum.pdf In at least some aluminum electrolytic capacitor manufacturing processes, there is actually a reforming step done after assembly, in addition to the initial forming. See page 9 of the Panasonic "Aluminum Electrolytic Capacitors Technical Guide", dated April 2013: http://industrial.panasonic.com/lecs/jp/i/29880/TAL_E/TAL_E.pdf The reforming process WILL NOT fix other things that may go wrong with the capacitor, such as failed seals allowing the electrolyte to dry out, or corrosion, or punch through which can result if the oxide layer is degraded and voltage is applied without current-limiting. The US DoD published a technical handbook detailing their policies and procedures for reforming aluminum electrolytic capacitors that sit in inventory for years, MIL-HDBK-1131. As of 1999 this is "for guidance only and should not be cited as a requirement, but the information in the handbook may be useful in determining or evaluating requirements." For non-mil-spec capacitors, it recommends inspection and possible reformation every 3-6 years of shelf storage. It recommends disposal after 12 years of shelf storage, but AFAICT they're just being conservative, possibly due in part to not having enough practical experience with reforming very old capacitors. Shelf storage is of course equivalent to having the capacitor in-circuit but unpowered. Having the capacitor powered in circuit for any significant length of time will reform the oxide to some extent based on the applied voltage, though not up to original factory spec. When I reform capacitors myself, I use a reforming voltage of 135% of the rated voltage. Since I use a suitably low current limit, this has no significant probability of damaging the capacitor, but as with the initial factory forming, provides some margin for further shelf life. In my experience, aluminum electrolytic capacitors in equipment that has been unpowered for 30 years or more almost always need reformation, but they almost always meet factory specs (capacitance, ESR, and leakage at rated voltage) after reformation. Since I don't tend to restore equipment newer than that, I don't have any empirical data on how much shelf life they can have without needing reformation. I'm not particularly advocating for or against reformation, as compared to replacement. Anyone restoring equipment with electrolytic capacitors is advised to to read the references and decide for themselves. Eric

11 years

14
23
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RM 380Z Special Control Unit (?)

by cube1＠charter.net

SOME of the later S100 systems had regulated supplies and then ditched the board regulators, usually leaving a place to put a regulator with just a jumper wire in place of the regulator. tony duell <ard at p850ug1.demon.co.uk> wrote: >> > >> > ... Which also may well not be RML original. The 380Z has a regulated PSU, >> > S100 has separate regulators on each board and an unregulated PSU. >> >> Indeed, although I do recall a heatsink mounted externally on the back of >> the chassis (where the fan would be on the later hardware) with the early >> machines - I just don't know details of the internal PSU. > >I was going to say that that heatsink didn't look original, but fortunately I >kept my mouth shut and didn't insert my foot :-) > >I've only seen the later black 380Z's with built-in 5.25" drives, first at school >and now the one I own. On those the PSU is entirely internal, it's a little >chassis that fits round the mains transformer and carries a PCB of >recctifiers, regulators, etc. For some odd reason the schematic of that is not >in the manual, I guess I should draw it out sometime. It's not complicated. > >Thinking about it, I do wonder what that heatsink/regulator is doing in an S100 >system. Most likely it is the original RML supply and somebody has connected >to the unregulated inputs to its regulators > >-tony >

11 years

2
1
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RM 380Z Special Control Unit (?)

by robert.jarratt＠ntlworld.com

I remember the Research Machines 380Z and wouldn't mind getting one should the opportunity arise. But I have no recollection of a "Special Control Unit", so does anyone know what this is? http://www.ebay.co.uk/itm/Faulty-Vintage-Research-Machines-380Z-Special-Cont rol-Unit-Computer-/331617471655? Some kind of peripheral maybe? Regards Rob

11 years

4
9
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Equipment available (Wichita, Ks)

by microfilm＠microfilm.kscoxmail.com

Still cleaning the shop, trying to be out by the end of the week-ish. We have the following equipment available: TU-80 family tape drive, in frame. Works, passes diagnostics. Make offer. Photos: http://microfilmks.com/LMSI/ Unknown power supply module. Has NCR part numbers but google gives no love. +5 (x2), -5, +12, -12. Make offer. Photos: http://microfilmks.com/Ebay/UnknownPSU1.jpg and UnknownPSU2.jpg Discom electron tube, PN 123788-2. These came out of COM microfiche cameras, and have a blue display. Not sure how to go about shipping them securely, but if you're interested, we can figure it out. I have several of these. DEC SHD1Z-ZZ SCSI drive cabinet, tower configuration. Has SCSI-2 personality module, power supply, SCSI terminator and cable, 6 drive trays for 50-pin drives. Also has 4 spare drive trays and one spare power supply. Includes 6 1.2G SCSI drives, or if you prefer, I can remove them to lower the shipping weight. Asking $50 obo. All shipping is from Wichita, Ks, 67213 --Shaun

11 years

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accidental post allowance

by jwest＠classiccmp.org

drlegendre wrote: ---- How did his last missive make it through to the list in the first place? Didn't Jay just recently say he was perma-banned? ---- Within moments after I posted that he was banned, I went to the mailman interface, and his account was not in the membership list. I assumed he had unsubscribed himself shortly after his first post. When I saw his next (and last post), I dug further. His email was on a "whitelist" along with all members of cctech. This was a vestige of how the old "two lists joined at the hip" was configured. So I had to manually remove him from the whitelist, even though he wasn't subscribed. My Apologies for the oversight, but I believe it is fixed now. Be advised that there is always a chance he's still subscribed under some other unknown/non-descript email address. I'll weed them out as they are discovered. J

11 years

5
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A Final Word (FINAL)

by slandon110＠gmail.com

On 7/30/15 6:55 PM, Jay West wrote: > You wrote.... >> I really dont see the reasoning behind my classiccmp ban, You just banned me for no reason.. > You are incorrect. Just because you don't understand the reason doesn't mean I banned you for no reason. I will not be dragged into a senseless passive-aggressive exchange about it. > >> Because of you I cant even come out to VCFMW with my 10 year old son.. > You are also incorrect on this point. I did not mention VCFMW at all. I banned you from classiccmp, not VCFMW. > >> You know how much thats going to hurt him that he doesn't get to show off his project that he worked so hard to program on his Apple II. Thats going to destroy him.. So I hope you are happy. >> Thanks for the fun times.. Hope this makes you sleep well at night knowing you destroyed a 10 year olds excitement. > Statements like the above are a good portion of the reason why you were banned. I did not destroy a 10 year-olds excitement. You did that all on your own, through your own actions. > > J > > > > > Jay Seriously go fuck yourself.. That is all. You are a Jackass. If i showed up to VCF Id promptly knock you on your ass, you and mos6581 both. Hence why Im not coming, you bitch boys arent worth sitting in a chicago jail over.. So go enjoy your dope smoking circle jerk and FUCK YOU

11 years

6
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IBM 5150 available ($)

by jwest＠classiccmp.org

Stopped in the local electronics haunt, and the owner directed me to a "Fine to Very Good" IBM 5150. I did not look at it closely, but externally appears to be very good shape with minor scratches on the under-side. It has two FH 5.25's, and a cassette port on back. He did say that "memory had been expanded". No monitor, keyboard, or mouse. He's asking $75.00. If someone has a serious interest, I'd be happy to go look at details on it. The owner is a friend and he'd certainly let me open it up if need be. I'd also be willing to pack/ship for the excruciating cost of. "A promise of a future beer" :) Best, J

11 years

2
1
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Minuteman II Launch Control Computer

by ben＠bensinclair.com

I recently visited the Minuteman II launch control facility in South Dakota, and was curious about the computers used there. Here's a photo of the rack, with the Boeing part numbers visible: http://i.imgur.com/KTaW3Il.jpg Some Googling of those numbers didn't really reveal much. People love to talk about the guidance computer in the missile itself, but I can't find much about what they used when turning the keys. I like the little placard on the computer about encrypted data in memory. The whole place is worth a visit if you're out that way. Does anyone have more information on these? Thanks! -- Ben Sinclair ben at bensinclair.com

11 years

1
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PDP-1 in Verilog (Incomplete) + More

by cube1＠charter.net

Sorry, not interested. My next project of that sort is for the IBM 1410. Kip Koon <computerdoc at sc.rr.com> wrote: >Hi Jay, >I don't know if you are into Motorola microcontrollers or not, but I'm looking for an IP core for the MC68HC11K Microcontroller as I can't find the actual chip on ebay. Would you be interested in implementing this microcontroller in VHDL? I'm trying to learn VHDL, but my many projects keep wanting my time. :) I believe there is plenty of reference material for you to use. I've collected some documentation myself that I would be happy to share if need be. Please let me know what you think. Take care my friend. > >Kip Koon >computerdoc at sc.rr.com >http://www.cocopedia.com/wiki/index.php/Kip_Koon > > > >> -----Original Message----- >> From: cctalk [mailto:cctalk-bounces at classiccmp.org] On Behalf Of Jan Adelsbach >> Sent: Thursday, July 30, 2015 3:32 PM >> To: General Discussion: On-Topic and Off-Topic Posts >> Subject: PDP-1 in Verilog (Incomplete) + More >> >> Hi all, >> >> At the time I've released my DG NOVA in Verilog I was also working on a >> PDP-1 in Verilog. Since I haven't >> touched the thing for quite some time I've decided to just release it before it catches dust. So far it can execute all kinds of programs, >> limitation is that they may not use IO as I haven't implemented the latter yet. (So essentially the same state as my DG NOVA >> implementation) It also supports optionally some PDP-1D features in the OPR and SKP instruction groups. Interrupts are implemented >> but untested. I'm not sure in which state I left the IOT controller if it works then both SBS and SBS16 might be usable. >> TL;DR: https://github.com/Jside/pdp1 >> >> The RCA110 was the project I was working on before I started the DG NOVA, it can execute some instructions but there is to much >> ambiguity in the reference manual on bitsavers in some cases which led me to abandon it. Especially since there is no software to >> cross-check. >> So for reference you can get it here: >> https://github.com/Jside/rca110 >> >> I wanted to mess around a bit with Chisel (a new HDL language used by the RISCV project) so here is the start of a CDC160 (currently >> only the instruction decoder): >> https://github.com/Jside/cdc160 >> >> I've also uploaded my DG NOVA to Github: https://github.com/Jside/nova1 >> >> MC14500B anyone? http://janadelsbach.com/soft/mc14500b.tar >> >> I will occasionally continue working on both the NOVA and PDP-1 (and maybe CDC160?). Also pull requests are welcome. >> As is obvious I *really* like implementing old computers in HDL languages but I always get stuck around IO since for any kind of >> flexibility as with an emulator I essentially would need to write a bus wrapper so that a (soft-core) processor executing Linux running >> an IO server could handle i.e. hard disks and magnetic tapes and that's I think really not worth it. So I might just go over and contribute >> to an emulator/simulator like SIMH if I'm in an must-implement-an-old-computer/processor mood ;). >> >> Regards, >> Jan >

11 years

1
0
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PDP-1 in Verilog (Incomplete) + More

by jan＠janadelsbach.com

Hi all, At the time I've released my DG NOVA in Verilog I was also working on a PDP-1 in Verilog. Since I haven't touched the thing for quite some time I've decided to just release it before it catches dust. So far it can execute all kinds of programs, limitation is that they may not use IO as I haven't implemented the latter yet. (So essentially the same state as my DG NOVA implementation) It also supports optionally some PDP-1D features in the OPR and SKP instruction groups. Interrupts are implemented but untested. I'm not sure in which state I left the IOT controller if it works then both SBS and SBS16 might be usable. TL;DR: https://github.com/Jside/pdp1 The RCA110 was the project I was working on before I started the DG NOVA, it can execute some instructions but there is to much ambiguity in the reference manual on bitsavers in some cases which led me to abandon it. Especially since there is no software to cross-check. So for reference you can get it here: https://github.com/Jside/rca110 I wanted to mess around a bit with Chisel (a new HDL language used by the RISCV project) so here is the start of a CDC160 (currently only the instruction decoder): https://github.com/Jside/cdc160 I've also uploaded my DG NOVA to Github: https://github.com/Jside/nova1 MC14500B anyone? http://janadelsbach.com/soft/mc14500b.tar I will occasionally continue working on both the NOVA and PDP-1 (and maybe CDC160?). Also pull requests are welcome. As is obvious I *really* like implementing old computers in HDL languages but I always get stuck around IO since for any kind of flexibility as with an emulator I essentially would need to write a bus wrapper so that a (soft-core) processor executing Linux running an IO server could handle i.e. hard disks and magnetic tapes and that's I think really not worth it. So I might just go over and contribute to an emulator/simulator like SIMH if I'm in an must-implement-an-old-computer/processor mood ;). Regards, Jan

11 years

2
1
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FFS: GE Mark Century programming manual

by silent700＠gmail.com

Here's a beast of a manual that I've scanned and posted. Will send the original for the cost of shipping (assume at least 5lbs of paper here, coming from 60070.) https://dl.dropboxusercontent.com/u/13043699/pics/GECENT.jpg Scan is here: http://chiclassiccomp.org/docs/index.php?dir=%2Fcomputing/GE Looks like numerical control for machining, not strictly a "computer" but certainly an early programmable device. 1970 edition but the earliest date on it is 1962. Can deliver to VCFMW. j

11 years

2
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A Final Word (FINAL)

by jwest＠classiccmp.org

One thing I will absolutely not abide here is drama of any kind. Regardless of anyone's sentiments in response to his post one way or the other, the list is no place for that. Suffice it to say, his subject line was correct. That was the final word he'll ever get on this list, and I have made his ban on freenode: #classiccmp permanent as well. For the record, my reasoning for the ban has more to do with other issues of his - not just the ones commonly posted here and on other forums. Please kill this thread, the last thing we need is a low SNR. Best, J

11 years

1
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A Final Word

by slandon110＠gmail.com

This is my final word I was recently banned from #classiccmp for selling a machine that was my own, I picked it up for someone else who hadnt paid me for it, sat in my closet for a year now. Hadnt heard from that person, tried contacting them, to no avail, I listed it on ebay the other day, only to wake up to find that I had been banned from #classiccmp for listing that machine. As far as I know its not against the rules to sell my own personal property. I was finally able to get a hold of the person who wanted it and he still does. I am currently arranging a way for him to get it. I know many of you hate me because im this horrible evil scammer pedophile, or thats what you think. Common sense says that if I was a horrible pedophile, I wouldnt have joint custody of my son, But I do. Because of what was posted online over the years. Yes I scammed over 10 years ago, thats in the past, Im not a bad person nor a pedophile. People do change you know. Im a hardworking person who tries his hardest to take care of his kid and family. Yes I enjoy computers.. I enjoy fixing them up and finding them homes. I've been treated terrible in this scene by a number of people. calling me names, you name it. I attended VCF 3 years in a row, Had a blast. This year I will not be attending due to the sheer number of threats I have received. I really wanted to bring my son this year. Hes 10. It would have been fun to share this with him. We really wanted to have a ccmp display during the 2016 Telephone show here in Michigan as well, and you all would have been welcome to come. But if you guy's don't want me in this scene just simply say so, and Ill quietly disappear. Thank you for your time and Good Day

11 years

3
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Wanted: IBM AS/400 in NY for a film

by jnc＠mercury.lcs.mit.edu

> From: Evan Koblentz > we always require a signed contract with strict rules about how our > artifacts can/can't be used by renters. I hope the contract includes a very sizeable 'liquidated damages' clause which comes into force when the artifact is significantly damaged (i.e. scraped paint, scratches, etc don't count) or destroyed; that number should be 5-10 times its assessed value. That would be to stop people like the film crew we heard of who borrowed something, deliberately destroyed it as part of a scene, and them calmly paid the lender the assessed value. If they're looking at having to pay a _ton_ of money if they pull that stunt, they're less likely to. Noel

11 years

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Wanted: IBM AS/400 in NY for a film

by steve＠oldcomputers.net

I received this email - they want am IBM AS/400 for a film - it doesn't have to work. They will pay for transportation and rent. Near Brooklyn NY I think. Email Bianca below if interested. ====================== Begin forwarded message: > From: Bianca Siu Davies <biancasiudavies at gmail.com> > It does not have to work, it would merely be set dressing for a film. If we could find one by mid-August, that would be great! I'm in New York and I can organize the shipping of it if need be. > > Thanks so much!! > Bianca. > Bianca Siu Davies >>> Art Department Coordinator >>> THE WIZARD OF LIES >>> O: 646-863-7493 >>> C: 415.420.8375 >>>

11 years

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Reforming capacitors (technical description, not politics)

by radiotest＠juno.com

At 4:10 PM 7/29/2015, drlegendre wrote: >... I have somewhere a document from Mallory ... that describes the evolution of the multi-section aluminum can electrolytic ... And at 09:43 PM 7/29/2015, Eric Smith wrote: >Definitely *very* interested. As am I. I have quite a bit of old Mallory literature in-house but don't recall seeing that. Dale H. Cook, Roanoke/Lynchburg, VA Osborne 1 / Kaypro 4-84 / Kaypro 1 / Amstrad PPC-640 http://plymouthcolony.net/starcity/radios/index.html

11 years

1
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DEC M705 vs M7050 in PC05

by j＠ckrubin.us

If you were following Joerg Hoppe's recent PC05 auction on eBay, you might have noticed that his system had an M705 in the backplane where I would have expected an M7050. This is the way he received it and the restored unit works as it should. Clearly the cards are similar but different but are they interchangeable? Would the backplane wiring be different and if so where would this be recorded? My copy of the PC04/05 maintenance manual (DEC-00-PCOA-D(1)) makes no mention of the M705 in this location. The PC04/05 print set on Bitsavers has the M705 on the module utilization list (p45) but crossed out with no reference notes. There is an ECO list on the sheet, showing PC05 ECO's 3, 16 and 30 but no specifics. Is there an available ECO log that would cover these notes? Then there's the K303, but that's another story... Jack

11 years

6
5
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H960 blank panel clips

by Arno_1983＠gmx.de

From: Charles Dickman: Tuesday, July 28, 2015 9:03 AM > If the posts and balls are metal, the panel sockets are going to crack > because there will not be any give in the shaft. If the ball and shaft > is replaced with a solid pin, the panel sockets will get damaged > because the socket will have to flex to conform to the pin. Ah, sorry. I had not payed close attention to how the counterpart works and automatically assumed it was some sort of metal spring fitted into a recess in the plastic panel that clips and holds onto the ball head. As I see now, it is just a tube-shaped outgrowth of the panel plastic itself. Phew... Anyway, thanks for clearing this up. Arno

11 years

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R: Re: IBM RT memory boards

by supervinx＠libero.it

I own two 7012 and could be interested in, if you can shipping overseas :) -------- Messaggio originale -------- Da: Sean Caron <scaron at umich.edu> Data:25/07/2015 16:17 (GMT+01:00) A: "General Discussion: On-Topic and Off-Topic Posts" <cctalk at classiccmp.org>,Sean Caron <scaron at umich.edu> Oggetto: Re: IBM RT memory boards If you're going to toss them otherwise, I'd be happy to keep them and give them a good home until someone came along who could use them ... but I'll take a backseat to anyone who's actually got one of those systems. Best, Sean On Sat, Jul 25, 2015 at 9:29 AM, Mike Stein <mhs.stein at gmail.com> wrote: > Hello, > > Thank you for your interest but it looks like my 70-year-old gray cells > have let me down again; it's been a few years since I scrapped this system > but after some discussion it turns out that these boards are actually for > an early RS/6000 (7012/7013). > > My apologies for raising your hopes/wasting your time ;-( > > (Anybody still interested?) > > mike > > ----- Original Message ----- From: "supervinx" <supervinx at libero.it> > To: "General Discussion: On-Topic and Off-Topic Posts" < > cctalk at classiccmp.org> > Sent: Saturday, July 25, 2015 5:54 AM > Subject: R: IBM RT memory boards > > >? I'm interested in, if you can ship overseas >> >> -------- Messaggio originale -------- >> Da: Mike Stein <mhs.stein at gmail.com> >> Data:24/07/2015? 18:21? (GMT+01:00) >> A: "General Discussion: On-Topic and Off-Topic Posts" < >> cctalk at classiccmp.org> >> Oggetto: IBM RT memory boards >> >> I've got 4 4Mx32 memory boards here from an old RT >> (AFAIR) in case anybody has a use for them. >> >> Each board has 8 512Kx40 (32 bits + 8 ECC) modules >> (20 pcs. 4x256). >> >> Edge connector is DS 42+49 >> >> m >> >> >> >

11 years

2
1
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DEC M705 vs M7050 in PC05

by jnc＠mercury.lcs.mit.edu

> From: Johnny Billquist > DEC made improved cards in many cases, where they added a 0 at the end > of the improved card. The other thing one will sometimes find (in PDP-11's at least, not sure about other machines) is that an M7xyz is replaced by the upgraded M8xyz, e.g. M7265, M7266 (11/34) -> M8265, M8266 (11/34A); M7685 (RM02/3) -> M8685; etc. Of course, there are plenty that follow no system at all, e.g. M7700 (RK05) -> M7680. > There are also examples where the zero was added, and the new module > replace a set of modules that combine to implement a device. The classic example, to me, being the M780 (KL11) -> M7800 (DL11). Noel

11 years

1
0
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need help getting a Sun Ultra-10 working

by lists＠y42.org

Hello Folks, I just assembled an Ultra-10 (replaced memory, CPU, NVRAM chip, IDE hard disk, IDE CDROM) and it seems to be hanging somewhere. I don't get anything from the VGA connection on the 1280x1024 LCD monitor that is connected, but on the serial console I see the output pasted below. The system does not respond to any input via the attached sun keyboard/mouse or via ttyA after printing the last line in the output below. Obviously, the NVRAM battery is dead, and I'm working on getting a replacement. Does anyone have a good source in Germany? The chip says "M48T59Y-70PC1U". Could the dead NVRAM battery explain the behavior described? thanks, Rob Urban ----- serial console output BEGIN ----- Hardware Power ON @(#) Sun Ultra 5/10 UPA/PCI 3.31 Version 0 created 2001/07/25 20:36 Probing keyboard Done %o0 = 0000.0000.0055.4001 Executing Power On SelfTest @(#) Sun Ultra 5/10 (Darwin) POST 3.1.0 (Build No. 626) 13:56 on 06/27/00 CPU: UltraSPARC-LC (Clock Frequency: 300MHz, Ecache Size: 512KB) Init POST BSS Init System BSS NVRAM NVRAM Battery Detect Test *********************** STATUS =FAILED TEST =NVRAM Battery Detect SUSPECT=NVRAM U13 MESSAGE=NVRAM Low Battery addr 000001ff.f1001ff0 exp 00 obs 10 Status of this POST run: FAIL manfacturing mode=CHAMBER Time Stamp [hour:min:sec] 28:6a:c1 [month/date year] 0b/2c 2130 Power On Selftest Completed Software Power ON0.0000.0000.0001 ffff.ffff.f00b.31a8 0000.3333.0200.001b @(#) Sun Ultra 5/10 UPA/PCI 3.31 Version 0 created 2001/07/25 20:36 Clearing E$ Tags Done Clearing I/D TLBs Done Probing Memory Done MEM BASE = 0000.0000.2000.0000 MEM SIZE = 0000.0000.1000.0000 11-Column Mode Enabled MMUs ON Copy Done PC = 0000.01ff.f000.201c PC = 0000.0000.0000.2060 Decompressing into Memory Done Size = 0000.0000.0006.eba0 ttya initialized Starting real time clock... Incorrect configuration checksum; Setting NVRAM parameters to default values. Setting diag-switch? NVRAM parameter to true Reset Control: BXIR:0 BPOR:0 SXIR:0 SPOR:1 POR:0 UltraSPARC-IIi 2-2 module Probing Memory Bank #0 256 + 256 : 512 Megabytes Probing Memory Bank #2 0 + 0 : 0 Megabytes Probing UPA Slot at 1e,0 Nothing There Probing /pci at 1f,0/pci at 1,1 at Device 1 pci108e,1000 network Probing /pci at 1f,0/pci at 1,1 at Device 2 SUNW,m64B Probing /pci at 1f,0/pci at 1,1 at Device 3 ide disk cdrom Probing /pci at 1f,0/pci at 1 at Device 1 Nothing there Probing /pci at 1f,0/pci at 1 at Device 2 Nothing there Probing /pci at 1f,0/pci at 1 at Device 3 Nothing there Probing /pci at 1f,0/pci at 1 at Device 4 Nothing there ----- serial console output END -----

11 years

3
4
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H960 blank panel clips

by jnc＠mercury.lcs.mit.edu

Saw this auction for a pair of H960 blank front panel clips: http://www.ebay.com/itm/391207099375 and though I'd pick them up... until they went for $30 (including shipping),at which point I decided I'd go back to my previous plan to fabricate some out of some scrap wood, and a pair of screws. Time to find someone who can do injection molding... (I don't think these could be 3D printed, the necks of the bulb-heads are under a lot of stress when removing panels, they often snap off; will 3D printed parts be that strong?) Noel

11 years

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Reforming capacitors (technical description, not politics)

by cube1＠charter.net

Better explanation than mine. Eric Smith <spacewar at gmail.com> wrote: >Some people seem to think that "reforming" an aluminum electrolytic >capacitor is some kind of cheat, akin to zapping NiCd cells or >rejuvenating CRTs. Actually reforming is the same electrochemical >process that the manufacturer uses to "form" the capacitor in the >first place, building up the aluminum oxide layer, before the sheet is >rolled into cylindrical form. The manufacturer typically uses a >forming voltage higher than the rated voltage, from 135% to 200%, to >provide margin for shelf life. > >When the capacitor goes unused for an extended time (shelf life), the >oxide layer gradually breaks down, increasing the capacitor's leakage >current and reducing the effective usable voltage of the capacitor, >which is proportional to the minimum oxide thickness. If the oxide has >developed spots that are too thin for the applied voltage, it may be >damaged ("punch-through") when that voltage is applied. Punch-through >tends to be a runaway process, so even a small amount of punch-through >usually completely ruins the capacitor. Reforming the capacitor by >applying current-limited power rebuilds the oxide layer to prevent >this type of damage, and to reduce the leakage current back to within >the specifications. The current limiting is what prevents the >reformation process from causing punch-through and damaging the >capacitor. Many of the capacitor vendors actually publish >recommendations for reforming their capacitors. > >See for example information on manufacture on pages 13-14 and a brief >recommendation of reforming procedure on page of 17 of Kemet >publication F3304 dated June 2009: > http://www.kemet.com/ProductCatalog%20Documents/F3304.pdf >Also pages 2-4 on manufacture and page 16 on "recondition" (reform) of >"CDE Aluminum Electrolytic Capacitor Application Guide": > http://www.cde.com/resources/catalogs/AEappGUIDE.pdf >Also pages 1-5 of Nichicon "General Description of Aluminum >Electrolytic Capacitors": > http://www.nichicon.co.jp/english/products/pdf/aluminum.pdf > >In at least some aluminum electrolytic capacitor manufacturing >processes, there is actually a reforming step done after assembly, in >addition to the initial forming. See page 9 of the Panasonic >"Aluminum Electrolytic Capacitors Technical Guide", dated April 2013: > http://industrial.panasonic.com/lecs/jp/i/29880/TAL_E/TAL_E.pdf > >The reforming process WILL NOT fix other things that may go wrong with >the capacitor, such as failed seals allowing the electrolyte to dry >out, or corrosion, or punch through which can result if the oxide >layer is degraded and voltage is applied without current-limiting. > >The US DoD published a technical handbook detailing their policies and >procedures for reforming aluminum electrolytic capacitors that sit in >inventory for years, MIL-HDBK-1131. As of 1999 this is "for guidance >only and should not be cited as a requirement, but the information in >the handbook may be useful in determining or evaluating requirements." >For non-mil-spec capacitors, it recommends inspection and possible >reformation every 3-6 years of shelf storage. It recommends disposal >after 12 years of shelf storage, but AFAICT they're just being >conservative, possibly due in part to not having enough practical >experience with reforming very old capacitors. > >Shelf storage is of course equivalent to having the capacitor >in-circuit but unpowered. Having the capacitor powered in circuit for >any significant length of time will reform the oxide to some extent >based on the applied voltage, though not up to original factory spec. > >When I reform capacitors myself, I use a reforming voltage of 135% of >the rated voltage. Since I use a suitably low current limit, this has >no significant probability of damaging the capacitor, but as with the >initial factory forming, provides some margin for further shelf life. >In my experience, aluminum electrolytic capacitors in equipment that >has been unpowered for 30 years or more almost always need >reformation, but they almost always meet factory specs (capacitance, >ESR, and leakage at rated voltage) after reformation. Since I don't >tend to restore equipment newer than that, I don't have any empirical >data on how much shelf life they can have without needing reformation. > >I'm not particularly advocating for or against reformation, as >compared to replacement. Anyone restoring equipment with electrolytic >capacitors is advised to to read the references and decide for >themselves. > >Eric

11 years

1
0
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H960 blank panel clips

by jnc＠mercury.lcs.mit.edu

> From: Chuck Guzis > Does anyone have a photo or mechanical drawing of one of these things? There are several kinds. These: http://ana-3.lcs.mit.edu/~jnc/tech/pdp11/jpg/H960FrontPanelClips.jpg are some of the better ones; they are connected to the rack via countersunk screws (go in the holes), and have embdedded nuts for use with the blank panels which have the matching captured bolts. The 'usual' ones don't have the embedded nuts, just the two ball/post things on the ends, and to attach them to the rack, they have (on the back) a pair of prongs with a fishhook-tang-like capture device on them. The back prongs were an even bigger crock than the ball-and-post things. The latter at least worked, even if they did occasionally break; the prongs wouldn't hold for s^*&^(*. I'll look and see if I have any of those, to take a photo of. Noel

11 years

6
5
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Microsoft multiuser Basic for the Altair 8800

by cube1＠charter.net

OK at the risk of restarting a long discussion about the value of reforming or lack thereof.... Reforming a cap means to apply power to the cap at or a little below its rated voltage but limiting the current with a resistor in series with the cap until the voltage drop across the resistor indicates acceptably low leakage current. At the low voltages in use on an Altair I typically use something in the range of 4.7k ohms. I have a dual 1-20v power supply to do this. The idea is that this redeposits some of the aluminum that had migrated into the electrolyte while the cap was idle reducing the leakage current of the capacitor. This procedure done correctly with the correct polariy and voltage will never harm the cap, so it isn't unreasonable to reform all of the filter caps on a linear supply like that on an Altair 8800. The current list!meeting resistor prevents the cap frm drawing too much current and overheating or worse until the reforming is complete or too much time has elapsed without reaching an acceptably low leakage current. Just google it and you will find articles on the procedures. As others have pointed out, this will not help if the cap has unacceptably large effective series resistance (ESR). On a linear supply, That will show up as unacceptably high ripple ac on top of the DC the supply is designed to provide. I would test the supply with at least SOME test Load before using it to supply the machine. When I did this to my Altair a few years back I think rather than disassembling the power supply to unsolder the caps I clipped one lead of each one so that one lead was free, but that then leaves one with the need to splice them back, but does avoid potential damage to the board. I also recently did that with an ALTOS which has switching supplies. Both would probably have done just fine without reforming. I also did in on an IMSAI, same story. I also did it to a pdp12, which had blown out rectifier before I did this. Doing a good job of restoring a machine does often mean disassembling and reassembling. It comes with the territory. It sounds like you !might have pretty limited electronics experience, and if that is the case you might try and find Someone local to help you over the humps. SAFETY FIRST. Kip Koon <computerdoc at sc.rr.com> wrote: >Hi Jay, >Thank you so much for the advice. What is reforming a capacitor? Does that mention the electrolytic capacitors may have to be repolarized? If so, how to you do that? How do you know if a power cap needs to be reformed or not? To get to the transformer, I'll have to take out just about everything including the card guides. Labeling the wires will be paramount too. I don't want to get those rascals mixed up! If remember my linear power supplies correctly, I don't need to put a load on them when I test them, but I will need to test the caps disconnected, correct? I doesn't sound too difficult, just tedious and much detail to consider. I definitely want to baby this thing. :) Thanks again for the restoration advice. I'll need it and more before I'm finished. Take care my friend. > >Kip Koon >computerdoc at sc.rr.com >http://www.cocopedia.com/wiki/index.php/Kip_Koon > > >> -----Original Message----- >> From: cctalk [mailto:cctalk-bounces at classiccmp.org] On Behalf Of Jay Jaeger >> Sent: Thursday, July 16, 2015 9:39 AM >> To: cctalk at classiccmp.org >> Subject: Re: Microsoft multiuser Basic for the Altair 8800 >> >> First of all, safety first when working around these power supplies. >> You have mains voltage exposed all over the place, including the front panel switch. >> >> What I typically do is take it all the boards out and disconnect the power supply, and pull it out. I then re-form the capacitors by >> taking them off completely or, more often, unsoldering one lead. In one case recently the power supply was regulated (an Altos >> computer), and the power transistors were inserted through the power supply case and into the board from the backside, making >> removal both a pain and a little risky, so I just clipped one lead of each larger in place to do the re-forming (it turned out that in that >> particular case, they really didn't need it). I'd be pretty surprised if you actually had to replace your capacitors. For reforming I have >> had pretty good luck with a 4.7K ohm resistor in serial with the capacitor, and in more than half the cases, the capacitors really didn't >> need it. >> >> The transformer is either good or not - and it is probably just fine. >> Just measure its output voltages. Do make sure that the transformer is wired for your voltage depending upon where you live. One >> could disconnect it first, but the odds of it putting out too high a voltage are very very slim, so long as it is wired for the mains voltage >> wherever you happen to live. Bad ones either put out nothing for one of the voltages (open winding) or get hot (shorted winding). >> Neither is dangerous to the rest of the power supply. >> >> Then, check all the voltages to make sure they are not way too high, and throw and oscilloscope on it to make sure that there isn't a >> whole lot >> of ripple (typically caused by a bad rectifier). Remember that on the >> original Altair and most S100 machines each board had its own regulator, so this isn't an exact thing. (On my machine, I actually had >> to add a second 8V supply in order to provide power for a backplane completely full of boards.) >> >> For bootstraps, perhaps look for a ROM board on eBay (a Bytesaver or the like), and burn yourself a ROM. >> >> For a serial card, you can find T-UART or IMSAI MIO and the like show up >> on eBay pretty frequently. Be patient so you don't overpay. ;) Real >> MITS Altair cards come up far less frequently. Make sure you research (say, on bitsavers.org/pdf) which ones support current loop if >> you really want to hook up a real teletype. >> >> Not sure where you'd find your multi-user basic, but there is quite a lot of Altair/S100 software available as part of the SimH >> environment, and a separate web site at http://schorn.ch/altair_6.php >> >> JRJ >> >> On 7/15/2015 1:56 PM, Kip Koon wrote: >> > Hi Drlegendre, >> > How did you go about checking things out before you applied power for the first time (again)? :) I think I need to check out the >> electrolytic capacitors and the transformer at least. >> > In my system, the front panel is wired to the backplane along with the power supply wires so when I do power up, how do I protect >> everything? >> > There are screws the power wires come from, but they are difficult to get to. Do I need to consider replacing any other caps? >> > Do you have a write up about your experience? Any help you can give in the hardware department is most appreciated. Thanks in >> advance. Take care my friend. >> > >> > Kip Koon >> > computerdoc at sc.rr.com >> > http://www.cocopedia.com/wiki/index.php/Kip_Koon >> > >> > >> > >> >> -----Original Message----- >> >> From: cctalk [mailto:cctalk-bounces at classiccmp.org] On Behalf Of drlegendre . >> >> Sent: Wednesday, July 15, 2015 1:15 AM >> >> To: General Discussion: On-Topic and Off-Topic Posts >> >> Subject: Re: Microsoft multiuser Basic for the Altair 8800 >> >> >> >> Hey Kip >> >> >> >> I can't help you with the software, but I just finished an Altair >> >> restoration (my first) a few months ago, and am still interested in >> >> getting the machine connected and actually doing something >> >> interesting. The Altair was almost totally below the radar by the time I really started getting up to speed on micros, which would >> have been around 1983-1984 or so. This one was sort-of given to me by a former colleague of mine, around eight years ago. It was a >> total basket case, a real pile.. but it seems to be sorted at this point. >> >> >> >> It would be great if you'd let me follow along, keep in touch and let >> >> me know how you're working to get the Altair linked up to the term, >> >> getting the system bootstrapped, loading software, etc.. that's been a problem here, figuring out the serial I card (or finding one to >> replace it, that does have docs). >> >> >> >> Best, >> >> Bill >> >> >> >> On Tue, Jul 14, 2015 at 11:56 PM, Kip Koon <computerdoc at sc.rr.com> wrote: >> >> >> >>> Hi Guys, >> >>> >> >>> I have finally decided to restore my original Altair 8800 which has >> >>> been in storage for over 30 years. Does anyone have a copy of >> >>> Microsoft's Multiuser Disk Extended Basic for the Altair 8800? When >> >>> I was in college in '79 to '81, in the computer room was an ASR-33 >> >>> Teletype and 3 Learseigler terminals connected to an Altair 8800B. >> >>> An IMSAI was also there connected to one >> >>> ASR-33 Teletype. I'd like to resurrect this multiuser Basic >> >>> software environment on my Altair someday once the restoration is complete. >> >>> Any help in securing a copy of all the necessary software would be >> >>> most appreciated. >> >>> Thanks a bunch in advance. Take care my friends. >> >>> >> >>> >> >>> >> >>> Kip Koon >> >>> >> >>> <mailto:computerdoc at sc.rr.com> computerdoc at sc.rr.com >> >>> >> >>> <http://www.cocopedia.com/wiki/index.php/Kip_Koon> >> >>> http://www.cocopedia.com/wiki/index.php/Kip_Koon >> >>> >> >>> >> >>> >> >>> >> >>> >> >>> >> > >> > >

11 years

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H960 blank panel clips

by jnc＠mercury.lcs.mit.edu

> There are several kinds. ... I'll look and see if I have any of those, > to take a photo of. Alas, I don't. I do have some of the third kind (which are intermediate between those two previously discussed; they have the holes for bolting to the rack, but don't have the captive nuts). > From: William Donzelli > I THINK YOU FORGOT SOMETHING... I linked to the eBay listing in the first post in the thread. Anyway, the sale's over now? > toober Ah, so it's you I've been buying PDP-11 stuff from! I like the user name! :-) Noel

11 years

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DEC Power Conditioner on Ebay

by dj.taylor4＠comcast.net

I ran into this looking for something else on ebay: Digital Constant Voltage Conditioner H7225 item 331591861028 I don't think I ever saw one of these before, were they of any use?

11 years

2
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DC300XL/P-600 tapes available

by microfilm＠microfilm.kscoxmail.com

While cleaning up the shop, I found a stockpile (qty: 85) of brand new, in the plastic wrap, Carlisle DC300XL/P-600 QIC tapes. They're arranged in one complete case of 50 (subdivided into boxes of 10, each of which has two smaller boxes of 5). The boss wants something for them, but didn't say how much. I'm asking $0.50 per tape, in lots of 10. $20 for the full case. You pay shipping from Wichita, Ks 67213. --Shaun

11 years

1
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Microsoft multiuser Basic for the Altair 8800

by computerdoc＠sc.rr.com

Hi Guys, I have finally decided to restore my original Altair 8800 which has been in storage for over 30 years. Does anyone have a copy of Microsoft's Multiuser Disk Extended Basic for the Altair 8800? When I was in college in '79 to '81, in the computer room was an ASR-33 Teletype and 3 Learseigler terminals connected to an Altair 8800B. An IMSAI was also there connected to one ASR-33 Teletype. I'd like to resurrect this multiuser Basic software environment on my Altair someday once the restoration is complete. Any help in securing a copy of all the necessary software would be most appreciated. Thanks a bunch in advance. Take care my friends. Kip Koon <mailto:computerdoc at sc.rr.com> computerdoc at sc.rr.com <http://www.cocopedia.com/wiki/index.php/Kip_Koon> http://www.cocopedia.com/wiki/index.php/Kip_Koon

11 years

7
10
0 0

H960 blank panel clips

by Arno_1983＠gmx.de

On Mon, Jul 27, 2015 at 11:58:36AM -0400, Noel Chiappa wrote: >Saw this auction for a pair of H960 blank front panel clips: > > http://www.ebay.com/itm/391207099375 > >and though I'd pick them up... until they went for $30 (including shipping),at >which point I decided I'd go back to my previous plan to fabricate some out of >some scrap wood, and a pair of screws. > >Time to find someone who can do injection molding... (I don't think these >could be 3D printed, the necks of the bulb-heads are under a lot of stress >when removing panels, they often snap off; will 3D printed parts be that >strong?) John Wilson <wilson at dbit.com> wrote: > So I'd be inclined to do a better design where > the posts are made of metal (or at least have a screw or stud through them > for extra strength). Hello, metal ball heads with a hex base on threaded posts are available as spares for R/C cars and similar, see e.g. ebay auction 161768309137 (10 for less than EUR 4,-- + S/H). You could probably just screw them into a suitably-sized hole in a plastic body like a self-tapping screw, or glue them in. Hope that helps, Arno

11 years

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Huge news! MARCH's 501c3

by evan＠snarc.net

We heard back from Uncle Sam @ the IRS: MARCH is finally a federal 501(c)3 non-profit charity. It took 9 years of prognosticating and 1 year of actual work. :) We needed to file using a different name than "Mid-Atlantic Retro Computing Hobbyists" so that's the other big piece of news here. Our charity's official name is: Wait for it ......... "Vintage Computer Federation". We'll continue to do business as MARCH. The new name, which happens to have the abbreviation "VCF" (get it? -- and yes we got permission from Sellam and from Erik K.), allows us to potentially expand beyond just being a regional computer club. Stay tuned for more announcements about this. :)

11 years

7
10
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Huge news! MARCH's 501c3

by couryhouse＠aol.com

March can now compete with chm ?for the larger cash donations and grants now I would assume! Sent from my Verizon Wireless 4G LTE smartphone -------- Original message -------- From: Jason Scott <jason at textfiles.com> Date: 07/27/2015 1:06 PM (GMT-07:00) To: "General Discussion: On-Topic and Off-Topic Posts" <cctalk at classiccmp.org> Subject: Re: Huge news! MARCH's 501c3 Congratulations to MARCH on the new phase of existence! On Jul 27, 2015 2:06 PM, "geneb" <geneb at deltasoft.com> wrote: > On Mon, 27 Jul 2015, Al Kossow wrote: > >? On 7/27/15 10:54 AM, Evan Koblentz wrote: >> >>? "Vintage Computer Federation". >>> >>> >> Great >> >> I hope Sellam gets on your ass over that. >> > > Al, don't be a dick. > > Evan clearly mentioned that he got Sellam's and Erik Klein's(sp?) OK on > the name. > > g. > > -- > Proud owner of F-15C 80-0007 > http://www.f15sim.com - The only one of its kind. > http://www.diy-cockpits.org/coll - Go Collimated or Go Home. > Some people collect things for a hobby.? Geeks collect hobbies. > > ScarletDME - The red hot Data Management Environment > A Multi-Value database for the masses, not the classes. > http://scarlet.deltasoft.com - Get it _today_! >

11 years

3
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Just got a big C= Haul

by slandon110＠gmail.com

Thought id share what I picked up about 2 hours north of me Pet 8032 with 8050 Drive and Matching Printer Amiga 500 with 590 HDD- Needs some work Brand new in Box C16 Brand New in Box Plus 4 Commodore Colt PC 2 VIC 20s. Ones an early one with silver label Lots of Disks for the A500 All in all not a bad haul for a 2 hour drive. The only thing im keeping is the Amiga 500, and maybe the colt PC the rest is up for grabs. If your interested in it let me know. I can deliver to VCFMW if its prepaid. Heres pics for you all to look at https://www.flickr.com/photos/67970316 at N08/sets/72157656357657105 Steve

11 years

5
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PDP-8 GTF question

by blstuart＠bellsouth.net

I need to pick the brains of some PDP-8 experts. According to the references I can find, especially the Small Computer Handbook, the GTF instruction should include the M837 interrupt inhibit bit in AC3. However, maindec 8E-D1HA test 05 seems to depend on this not being true. Running the GTF instruction on my 8/M when the inhibit FF is set results in a 0 in AC3. Furthermore, both simh and Doug Jones' emulator omit the interrupt inhibit bit in the GTF instruction. In fact Dr Jones' emulator has a /*?*/ comment in the code. Does anyone know the origin of this discrepancy? Was the behavior the same on pre-Omnibus versions of the 8, or did earlier address extensions include that bit in the GTF result? I came across this oddity in the course of writing an emulator of my own, and I'd like understand what's going on here a little deeper than "ignore the documentation, and make it work like the real hardware." Thanks in advance, BLS

11 years

3
6
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First Computer Store

by COURYHOUSE＠aol.com

I find USB useful and with USB 3 pretty darn quick! only downside it does not like to run 45.5 baud to run our 60 wpm UPI Teletype machine in the Journalism Display. Hey anyone have a AP Teletype we need one in AP dress too! Ed# _www.smecc.org_ (http://www.smecc.org) In a message dated 7/26/2015 6:14:58 A.M. US Mountain Standard Time, ard at p850ug1.demon.co.uk writes: > > Remember when USB was referred to as the Useless Serial Bus after it was introduced? I think it was a solid 1-2 > years after it was introduced that I began to notice peripherals designed for it. I still call it 'Useless Serial Botch' most of the time. It's not a bus, after all. -tony =

11 years

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