test-drb March 2004

test-drb@ccmp.vtda.org

273 participants
673 discussions

by marvin＠rain.org

As quite a few people are aware, I tend to *really* like documentation and books. Today was a good day for that as I acquired part of the library from someone who had died a few years ago and was into computers. The computer related books ranged from the 50's to the early 80's. A couple of books I had not seen but look to be very interesting are: The Computer from Pascal to von Neumann - Goldstine The Analytical Engine - Bernstein Sequential Machine: Selected Papers - Moore There were quite a few books on software design, digital hardware design, analog and hybrid computer design, compter logical design, operating systems (including Tanenbaum), etc. This is enough to keep me busy for a while checking them out :). Unfortunately, an H-89 had already been recycled but there is still the possibility that the manuals, etc. are still around. After I cull out the books I want, I'll list them on the Computer Marketplace.

20 years, 2 months

H744 +5 supply - easy to fix?

by brad＠heeltoe.com

I finally got my TS11 racked this morning and after a good cleaning found that it has no +5v. (I must say, I love DEC manuals...) Looks like the H744 supply is not working. Anyone know about these? Are they easy to fix? Should I just pull it, find a schematic and start probing? (anyone have one they want to part with? :-) thanks! -brad

20 years, 2 months

H744 +5 supply - easy to fix?

by GOOI＠oce.nl

Hello Paul, just to enable all readers to understand I'll answer in English. The "RCD" (say Dutch Radio Control Service) has changed their policy since Sept, 1st, 2003. You can get -if still available- within some restrictions (depends on the license) the call you like (for $$$). I had the C license, and wanted to "upgrade" from PE1CKF to PE1PDP, but I was studying for the morse exam. I passed the very last morse code exam last December, and changed the prefix also to reflect the A license that I now hold. For insiders: I hope to be QRV on HF in a few months, and what that makes special is that I use equipment from RACAL, no Japanese toys! What is RACAL? Check my home page on www.pdp-11.nl and on the opening page at the bottom right, click on the animated gear box ... 73, - Henk, PA8PDP. > -----Original Message----- > From: Paul Koning [mailto:pkoning@equallogic.com] > Sent: donderdag 4 maart 2004 15:10 > To: cctalk(a)classiccmp.org > Subject: RE: H744 +5 supply - easy to fix? > > > >>>>> "Gooijen" == Gooijen H <Gooijen> writes: > > Gooijen> success with your repairs, - Henk, PA8PDP > > Aardige roepletters! Ik wist niet dat de RCD tegenwoordig roepletters > op verzoek leverde. > > paul, ni1d, ex-pa0pkg

20 years, 2 months

8Kx8 EPROMs -- was Re: MS BASIC for a Panasonic HHC RL-H1400

by pete＠dunnington.u-net.com

On Mar 4, 14:52, John Allain wrote: [ about Motorola MCM68764 EPROMs ] > > Fancy parting with a few? They're 24-pin 8Kx8, which makes > > them particularly useful for some DEC boot ROMs > > Spit out some part numbers for compatible EPROMs and > I'll check my cache of pulls for you. Thank you. Trouble is, I don't know of any equivalent EPROMs, except the Motorola MCM68766 and SCM90448 ;-) All the other 8Kx8 EPROMs I know are 28-pin. While I remember, does anyone know what DEC ROMs 23-398E4 and 23-399E4 are? They're in Motorola SCM90448Cs, which is what reminded me. I can't remember what they came out of; possibly a PDT. Anyone know about 23-126E4 and 23-127E4 (mask ROMs)? Does anyone have any KDF11-B or KDJ11-B boot ROMs I could add to my collecton? -- Pete Peter Turnbull Network Manager University of York

20 years, 2 months

MS BASIC for a Panasonic HHC RL-H1400

by pete＠dunnington.u-net.com

On Mar 4, 10:53, Roger Merchberger wrote: > > > > The insurance ROMs are Motorola MCM 68764C and appear to be UVEPROMs. > > > > > > You and the rest of the HHC community. I've got an HHC myself, and all > > > mine has are the insurance EPROMs, too. > > I actually have about 20 *pounds* of these eproms... Fancy parting with a few? They're 24-pin 8Kx8, which makes them particularly useful for some DEC boot ROMs (which is the only place I've seen them before). They fit *my* programmer :-) -- Pete Peter Turnbull Network Manager University of York

20 years, 2 months

H744 +5 supply - easy to fix?

by pete＠dunnington.u-net.com

On Mar 4, 7:44, Tom Uban wrote: > I've seen a number of the rectifiers fail, so I would concur that it > is a common component to fail. Also, those supplies have always > whistled, even when new from the factory. Well, I've seen a few that don't whistle, and I don't really think they should; the coil laminations are supposed to be glued together and encapsulated. -- Pete Peter Turnbull Network Manager University of York

20 years, 2 months

TRS-80 Model 12 crt substitution - Now I need help with 8" drives

by redodd＠comcast.net

Thanks to all who replied to the crt problem. The crt from the TRS-80 Model 4 was a perfect replacement for the Model 12. Now I have 2 - 8" Tandon thinline TM848E dsdd drives that have problems (in the Model 12). Drive 0 (lets call it A) used to work fine but now all it does is blink (the red busy led). 3 blinks followed by 1 blink or maybe it's 1 blink followed by 3 blinks, hard to tell. Drive 1 (call it B) always made noise and wasn't as reliable as A. I took A out, made B drive 0 and installed the resistor pack. Now B won't boot, I get to "initializing" and then I get a seek error. I have an original TRSDOS 2.0b disk and a copy and both used to work. Both get the same error. The drives have what I am going to call a logic board that's easy to remove. It has the drive and power connectors on it. I've tried every combination of mixing drives and logic boards but I still get the same errors. Does this blinking make sense to anyone and can I cure the seek errors on the other drive? Thanks again for listening to my ranting. Ralph

20 years, 2 months

H744 +5 supply - easy to fix?

by GOOI＠oce.nl

Just my 2c. I repaired 2 H744's up till now. They are indeed an easy piece to work on. One had a defective rectifier bridge (the 1 x 1 inch square block with 4 terminals) and the other was more peculiar: one big electrolitic capacitor (AFAICR it is connected directly to the PCB, fixed with screws) made a short circuit between the housing of the capacitor and a trace on the board. The plastic insulation of the capacitor some how was that bad to allow the short circuit ...! success with your repairs, - Henk, PA8PDP > -----Original Message----- > From: Brad Parker [mailto:brad@heeltoe.com] > Sent: woensdag 3 maart 2004 22:39 > To: General Discussion: On-Topic and Off-Topic Posts > Subject: H744 +5 supply - easy to fix? > > > I finally got my TS11 racked this morning and after a good cleaning > found that it has no +5v. (I must say, I love DEC manuals...) > > Looks like the H744 supply is not working. Anyone know about these? > Are they easy to fix? Should I just pull it, find a schematic and > start probing? > > (anyone have one they want to part with? :-) > > thanks! > > -brad

20 years, 2 months

H744 +5 supply - easy to fix?

by pete＠dunnington.u-net.com

On Mar 4, 8:22, Gooijen H wrote: > I repaired 2 H744's up till now. > They are indeed an easy piece to work on. > One had a defective rectifier bridge (the 1 x 1 inch square > block with 4 terminals) and the other was more peculiar: > one big electrolitic capacitor (AFAICR it is connected > directly to the PCB, fixed with screws) made a short circuit > between the housing of the capacitor and a trace on the > board. The plastic insulation of the capacitor some how was > that bad to allow the short circuit ...! Hmmm... one of mine had a faulty rectifier too. Not hard to diagnose or replace, but I wonder if that's a common failure? Another one had a bad filter cap -- but it had died of age (leaked) rather than causing a short. Another common "problem" seems to be whistling from the coil, if it's begun to delaminate. Probably a sign of previously running hot, and not necessarily anything to worry about. Several of my "brick" PSUs had faulty bulbs, and I found the easiest way to fix that ws to replace the bulb with an LED and a resistor, as found on the later versions. -- Pete Peter Turnbull Network Manager University of York

20 years, 2 months

86/330 Problem(s)

by hirschopd＠msn.com

Joe, We solved the hardware portion of our problem and are now trying to resolve some iRMX system issues. How do I get availability and price on some of the Intel Manuels included in your list and that of Alossow's. Paul Hirsch >From: "Joe R." <rigdonj(a)cfl.rr.com> >Reply-To: "General Discussion: On-Topic and Off-Topic >Posts"<cctalk(a)classiccmp.org> >To: "General Discussion: On-Topic and Off-Topic Posts" ><cctalk(a)classiccmp.org> >Subject: Re: 86/330 Problem(s) >Date: Sat, 28 Feb 2004 12:27:28 -0500 > >At 02:27 AM 2/28/04 +0000, you wrote: > >Joe, > >do you have part numbers on the booards you have? > >Paul Hirsch > > > Here is a link to a Multibus webpage that I've been working on. ><http://www.classiccmp.org/hp/multibus/multibus.html>. MOST of the cards >that I have are listed there along with descriptions, part numbers and >pictures. It's still a work in progress so there are some missing bits and >pieces and I still have a stack of cards to add to it. It seems like >everytime I turn over a rock around here I find more Multibus stuff :-) > > FWIW I gutted* four Intel 86/330s a couple of years ago so I have all >the >cards for them. > > *Before anyone complains about me gutting vintage systems I'd like to >point out that these had had the hard drives removed before I got them and >I didn't have any Sw or docs for them and that I spent several months >trying to track down the stuff before I gave up and stripped them. I posted >several requests on this list and didn't get a single reply. > > Joe > > > > > > > >>From: "Joe R." <rigdonj(a)cfl.rr.com> > >>Reply-To: "General Discussion: On-Topic and Off-Topic > >>Posts"<cctalk(a)classiccmp.org> > >>To: "General Discussion: On-Topic and Off-Topic Posts" > >><cctalk(a)classiccmp.org> > >>Subject: Re: 86/330 Problem(s) > >>Date: Fri, 27 Feb 2004 18:17:09 -0500 > >> > >>At 02:28 PM 2/27/04 -0800, you wrote: > >> >On Fri, 27 Feb 2004, Paul Hirsch wrote: > >> > > >> >> We have an 86/330 that will not boot. We are using the RMX 5.1 > >>Operating > >> >> System. Following power on we compete the SCT Test and begin >booting > >>and > >> >> get a "Divide overflow occured". We have replaced the 8086 >procrsser, > >>the > >> >> 8087 coprocessor and the memory boards. At this point we are out of > >>options > >> >> unless it is the cpu board (144548-003 Rev C). 1) if any one has >any > >>advice > >> >> I would appreciate it, or if anyone has a board or computer that >they > >>would > >> >> like to sell. > >> > > >> >Sounds like a software problem. > >> > > >> >What's an 86/330? > >> > >> Sounds like an Intel 86/330 computer (8086 CPU Multibus system). I >have > >>parts for them and I've already replied to him. > >> > >> Joe > >> > >> > > >> >-- > >> > > >> >Sellam Ismail Vintage Computer > >>Festival > >> > >--------------------------------------------------------------------------- > >>--- > >> >International Man of Intrigue and Danger > >>http://www.vintage.org > >> > > >> >[ Old computing resources for business || Buy/Sell/Trade Vintage > >>Computers > >> ] > >> >[ and academia at www.VintageTech.com || at > >>http://marketplace.vintage.org ] > >> > > >> > > > > >_________________________________________________________________ > >Watch high-quality video with fast playback at MSN Video. Free! > >http://click.atdmt.com/AVE/go/onm00200365ave/direct/01/ > > > > _________________________________________________________________ Fast. Reliable. Get MSN 9 Dial-up - 3 months for the price of 1! (Limited-time Offer) http://click.atdmt.com/AVE/go/onm00200361ave/direct/01/

20 years, 2 months

← Newer
1
...
61
62
63
64
65
66
67
68
Older →

Jump to page:

2024

2023

2022

2021

2020

2019

2018

2017

2016

2015

2014

2013

2012

2011

2010

2009

2008

2007

2006

2005

2004

2003

2002

2001

2000

1999

1998

1997

test-drb March 2004