test-drb

test-drb@ccmp.vtda.org

101090 discussions

by COURYHOUSE＠aol.com

for some reason I remember using a piece of plastic tubing? Ed# _www.smecc.org_ (http://www.smecc.org) In a message dated 7/20/2015 11:13:32 A.M. US Mountain Standard Time, jwest at classiccmp.org writes: What I'd really like, is one of those "light bulb replacement tools" for the 2100 :) As anyone knows who has replaced them before, it's a bit of a frustrating pain to get them inserted just right given clearences and such :) I'm not positive, but I seem to recall back in foggy memory that there was actually a tool for this. J

11 years

AlphaServer 4100 CPU fan

by binarydinosaurs＠gmail.com

Folks, I didn't realise there'd been a clasiccmp server meltdown, wondered why I wasn't getting mails :) We still have a few AS4100s out there in the field and CPU fans are becoming scarce, so being canny we sourced some *almost* identical replacements to no avail. Original spec for the fan is 12V 0.17A, our replacements are 12V 0.18A and the console still reports them as failed. I've sanity checked by using a processor board with a good fan and still nothing. Could the 0.01A cause THAT much of an issue? The wiring is a good 3" longer too but I didn't think that would cause problems either. Any help appreciated. -- adrian/witchy Owner of Binary Dinosaurs, the UK's biggest home computer collection? www.binarydinosaurs.co.uk

11 years

moving cleanout - partial DECmate I / VT278

by COURYHOUSE＠aol.com

what is condition of the mod 100 trs 80? more concerned abut visual as it would go in a tools of the journalist over at the univ or if anyone else has one they could toss in a box and send this way. They were one of the early "issued items" to some reporters to phone home stories. When about it... the 'tools of the journalist' throughout the ages makes for a pretty interesting display especially when you take in to account print, radio and television. the dec may be to much to box and mess with and I certainly can't make the road trip although it has to be better than our 104 degree weather here! Ed# www.smecc.org In a message dated 7/20/2015 12:22:27 A.M. US Mountain Standard Time, hilpert at cs.ubc.ca writes: On 2015-Jul-19, at 10:45 PM, couryhouse wrote: > What are you going to do with it?Looking. For a wt78 but.... this fell in our lap.... While I did expect DEC-anything would attract more interest, I was figuring people would have read my message from earlier in the day, here's the extract/backgrounder: So my house sold yesterday after < 3 days on the market (the market here is nuts). I have about two months to move, so a bunch of stuff has to disappear. Location is the Vancouver, BC, Canada region (Port Moody more precisely). Most of this stuff is larger and I'm not going to have a lot of time to pack & ship, so local pickup is expected. If there is competition for something I guess it goes to the one willing to offer the greater number of bucks, otherwise items are free as the alternative destination is recycling/scrap. Any bucks involved are not because I expect a lot (or anything), but just to sort out who 'values' it the most if there is multiple interest in an item. I reserve the right to be whimsical in any decision. At this point three (distant) parties have inquired about this item. No, I don't want to scrap it, but I can't make promises for shipping something this size at this time. If someone is "really interested" (you have the other bits for example), let me know. Shipping just the CPU board may be another option. (There has been no interest in all the other stuff at this point except the TRS-80 M100 and a question about the XT-clone.) > -------- Original message -------- > From: Brent Hilpert <hilpert at cs.ubc.ca> > Date: 07/19/2015 9:29 PM (GMT-07:00) > To: "General Discussion: On-Topic and Off-Topic Posts" <cctalk at classiccmp.org> > Subject: Re: moving cleanout - partial DECmate I / VT278 > > Further to my earlier message today, something else to go: > > DECmate I / VT278 monitor & CPU > > This is the VT100 monitor/housing with the 6120-PDP8-microproc-based CPU board in one of the logic slots. > Sadly, missing the keyboard and floppies unit, so it's not complete. > > IIRC, I faked a keyboard-present signal at the keyboard-jack some time ago and got it to produce some boot text on the screen. > > See for example: http://so-much-stuff.com/pdp8/decmateI/decmateI.php > > . . found my notes about it from 2011: > > ------------------------------ > > DEC DECMate VT278-AC > > 1983 > > System: > > ? LSI PDP-8 in VT100 case. > ? 6120 microprocessor (D1-6120-9 8) > ? 6 * SIP memory modules w 4 chips each (21-17559-AA / 8252 DP) > ? 2 * 6402 (UART) > ? 2 * 6121 (PIO) > ? SND 5027 D (video controller) > > Pros & Cons: > > ? CON: Missing disk drive. > ? CON: Missing keyboard. > > 2011 Jul: Powered up. PWR-OK and CPU-OK LEDs lit, CRT filament lit. No raster. Schematic obtained from bitsavers. No video or sync signals from processor board to monitor board. CG CHAR CLK to CRT Controller chip is present (1.5MHz), but no sync signals out from CRT Controller. ROM, CPU, CRTC socketed chips rocked for contact, no change. CRT Controller may not be getting initialised in initial ROM boot process. > > Connecting ring (data) to tip (+12V) on keyboard connector after power-up brings up SET-UP message and flashing cursor after several seconds. > > ------------------------------ >

11 years

moving cleanout - partial DECmate I / VT278

by couryhouse＠aol.com

What are you going to do with it?Looking. For a wt78 but.... this fell in our lap.... Sent from my Verizon Wireless 4G LTE smartphone -------- Original message -------- From: Brent Hilpert <hilpert at cs.ubc.ca> Date: 07/19/2015 9:29 PM (GMT-07:00) To: "General Discussion: On-Topic and Off-Topic Posts" <cctalk at classiccmp.org> Subject: Re: moving cleanout - partial DECmate I / VT278 Further to my earlier message today, something else to go: DECmate I / VT278 monitor & CPU This is the VT100 monitor/housing with the 6120-PDP8-microproc-based CPU board in one of the logic slots. Sadly, missing the keyboard and floppies unit, so it's not complete. IIRC, I faked a keyboard-present signal at the keyboard-jack some time ago and got it to produce some boot text on the screen. See for example:? http://so-much-stuff.com/pdp8/decmateI/decmateI.php . . found my notes about it from 2011: ------------------------------ DEC DECMate VT278-AC 1983 System: ? LSI PDP-8 in VT100 case. ? 6120 microprocessor (D1-6120-9 8) ? 6 * SIP memory modules w 4 chips each (21-17559-AA / 8252 DP) ? 2 * 6402 (UART) ? 2 * 6121 (PIO) ? SND 5027 D (video controller) Pros & Cons: ? CON: Missing disk drive. ? CON: Missing keyboard. 2011 Jul: Powered up. PWR-OK and CPU-OK LEDs lit, CRT filament lit. No raster. Schematic obtained from bitsavers. No video or sync signals from processor board to monitor board. CG CHAR CLK to CRT Controller chip is present (1.5MHz), but no sync signals out from CRT Controller. ROM, CPU, CRTC socketed chips rocked for contact, no change. CRT Controller may not be getting initialised in initial ROM boot process. Connecting ring (data) to tip (+12V) on keyboard connector after power-up brings up SET-UP message and flashing cursor after several seconds. ------------------------------

11 years

Multibus arbiter design

by spacewar＠gmail.com

Is anyone aware of any published detailed designs of Multibus arbitration circuitry, NOT using the Intel bus arbiter chips (e.g., 8218, 8219, 8289, 82289)? I know various vendors making Multibus CPU cards for non-Intel CPUs (e.g., 68K or NS 32K) sometimes designed their own arbiters out of TTL and/or PALs, but I haven't found any schematics. The only thing I've found so far is an application note "A Multibus Arbiter Design for 10 MHz Processors" in the 1988 AMD PAL Device Handbook, but I'd like to see other examples. I'm considering designing a Multibus I/O card that needs to be a bus master, and while an 8289 or 82C89 would do what I want, they're relatively hard to find and expensive, so I'd rather just do it in my FPGA, with suitable buffering to meet the Multibus electrical specs. It appears that the inner workings of the Intel 8289 arbiter are documented in US patent 4,257,095. The Intel MDS-800 circa 1975 used a bunch of TTL, but it was pretty tightly intertwined with 8080-specific logic, and since the MDS-800 predated the Multibus spec and has a few obvious differences from it, I don't think it serves as a particularly good bus arbiter design example.

11 years

PDP 11 gear finally moved

by cube1＠charter.net

Well, all I can say is that my experience differs. I have had newer capacitors fail, and old ones, too, of course, but nothing points to wholesale replacement as a cost or time effective strategy, especially on something like an Altair. FWIW, I don't run my vintage machines all that often. Of course reforming a bad capacitor, whatever the failure mode, is going to be useless. Tothwolf <tothwolf at concentric.net> wrote: >On Fri, 17 Jul 2015, Jay Jaeger wrote: >> On 7/17/2015 1:33 PM, Rich Alderson wrote: >> >>>> It is generally a good idea to re-form electrolytic capacitors in >>>> power supplies, and to bench check the power supplies (under some kind >>>> of load) before actually applying power to the whole unit. >>> >>> It is always a good idea to replace electrolytic capacitors in power >>> supplies. The rest of the advice is sound. >>> >> Replace - no, I don't agree - especially not for those of us who don't >> have the kind of budget that your organization has. In my experience, >> for equipment of this quality and vintage, 95% or more of the time an >> hour to a few hours of re-forming is all that is necessary - and as Tony >> has pointed out, even that is not often really necessary. > >Replace - yes, *especially* if you don't have a big budget. Aluminum >electrolytic capacitors are CHEAP and easy to obtain. Replacement >semiconductors by comparison are expensive and can be quite difficult to >find. > >While it might be worthwhile reforming a special purpose NOS electrolytic >that isn't much older than 15-20 years old, reforming 20-30 year old >heavily used (read: past usable service life; evaporation of the >electrolyte, corrosion of the foils and especially foil to terminal >junctions, etc) is a complete and total waste of time. > >Ironically, 20-30 years ago this same mindset used to persist with people >who collected vacuum tube (valve) based radios and television, however >that attitude no longer seems to be present in those communities today >(not worth risking an irreplaceable transformer or inductor over >$5.00-$10.00 worth of aluminum electrolytics).

11 years

moving cleanout - IBM XT(s), assorted macs, green-screen NTSC monitors, TRS-80 types, etc

by hilpert＠cs.ubc.ca

So my house sold yesterday after < 3 days on the market (the market here is nuts). I have about two months to move, so a bunch of stuff has to disappear. Location is the Vancouver, BC, Canada region (Port Moody more precisely). Most of this stuff is larger and I'm not going to have a lot of time to pack & ship, so local pickup is expected. If there is competition for something I guess it goes to the one willing to offer the greater number of bucks, otherwise items are free as the alternative destination is recycling/scrap. Any bucks involved are not because I expect a lot (or anything), but just to sort out who 'values' it the most if there is multiple interest in an item. I reserve the right to be whimsical in any decision. The following is 'off-the-top-of-my-head', I haven't examined this stuff in awhile. If someone would like a photo of something, let me know. Additional stuff may filter out in the near future. ======== XTs IBM 5160 (XT) - CPU with one floppy and hard drive, but the hard drive is flaky (booted from floppy last time I checked) - clicky-keyboard with special coloured keycaps for some video-editing system, still functions as normal keyboard, missing one keycap (whatever is immed. below the RETURN key) - IBM 5151 green-phosphor monitor XT-class clone labeled "IDM Research X88 Turbo" not readily bootable, IIRC the 'multi-function' board was damaged by battery leakage, the hard drive is flaky on this one too, IIRC might be consider for parts/modules or as a base to complete an XT - with keyboard & amber-phosphor monitor ======== Macs Mac Quadra 605 / LC475 68040 pizza box - with ADB keyboard and mouse - no monitor Mac Performa 5300CD beige all-in-one, kind of the all-in-one predecessor to the original iMac - with ADB keyboard and mouse Mac PowerPC tower beige G3 - with ADB keyboard and mouse - no monitor yes, bland and unexciting, the redeeming point is it's kind of a "multi-medium machine": zip drive floppy drive CD-ROM drive SCSI bus IDE bus RS-232 USB ethernet some video/audio IO original iMac Rev A 'the very first iMac model', bondi-blue of course - complete with puck mouse, the proper keyboard and the proper 'clear' power cable - original Mac OS8 install media and box I think it has 40 or 60MB of memory but could really do with more - a couple of memory sticks were zapped as I was swapping them testing another machine. I'm not completely sure how many ADB keyboard/mouse sets there are, at least 2. ======== NTSC monitors 4 green-phosphor 12" NTSC monitors. I think 2 of them will go and I may hang on to 2. Typically used with late-70s / early-80's micros. I have to hang on to one of them to go with my SWTPC CT-1024 terminal, for example. One of them (NEC) was originally sold in a package with and used with an Apple II. ======== TRS-80s 2 or 3 TRS-80 CoCos TRS-80 Model 100 the laptop TRS-80 portable/luggable I'd have to check/confirm on this one, it was at the radio museum, if it's there it should go. ======== bonus circa-1980 colour TV, 13-14" If you really want the authentic (i.e. awful) RF-modulated-display experience from your vintage 80's micro, without the mass of a 17,19,21" CRT, this could be it. ================================= =================================

11 years

Linear Power Supply (Conversion Equipment Corp) from a basic four 510

by ad＠ardiehl.de

The one from my 510 does not supply the main +5V, all the other voltages are present. Does someone have a schematic for that one, would me more easy. I have uploaded pictures here: http://basicfour.de/mai510-PSU/small/ Thanks a lot Armin

11 years

MFM reader emulator

by djg＠pdp8online.com

I'm doing another run of boards. The description of the board changes and the expected price are at: http://www.pdp8online.com/mfm/board_revb.shtml If you desire any please respond by email not to list with 1) How many bare boards you wish. I will assume production boards unless you state how many of the ENIG boards available now you wish. Production boards may be a monthish. 2) If you wish the surface mount chips installed on the bare boards. 3) How many fully assembled boards you wish. The PCB is included. 4) For fully assembled boards do you wish a BeagleBone Black (BBB) provided with it. 5) Any questions you have.

11 years

Front Panels Sample layout.

by rodsmallwood52＠btinternet.com

Hi Guys! Further to my previous email. If anybody would like to see the artwork I can send you a copy. Its in *.svg format. Regards Rod

11 years

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