test-drb April 2015

test-drb@ccmp.vtda.org

182 participants
220 discussions

by robert.jarratt＠ntlworld.com

The other day my RD54 just stopped rotating, dead in its tracks, while it was running. I guessed one of the motor control power transistors may have failed. I assume they are the series of 6 chunky ones attached to a single heatsink. I have desoldered them (en-masse) and tested them with a Peak DCA55 tester, and they all appear to be working. Does anyone have any other suggestions? Has anyone ever repaired an RD54 control board? Regards Rob

10 years, 1 month

Help needed please re possible loss of a Burroughs B7800 CPU

by evan.linwood＠eastek.com.au

For those who don't know, Monash University (Melbourne Australia) has had the chassis of a B7800 CPU sitting around under a stoir case, left over from the days when a series of large Burroughs systems had been in use there during the seventies. I'm no expert on Burroughs systems, but from all the Internet based trawling I've done over the years it appears that Burroughs had a 'scorched earth' policy, and systematically reclaimed and disposed of all B5000 and onward family machines. At least to date, I haven't been able to find any other surviving example of a B5000 family machine (or major components). Naturally I'd be very happy to be proved wrong. Unfortunately all cards and power supplies had been removed but it still had the basic frame, backplane (very impressive in it's own right) and two large front control panels all in place (also very impressive). (I've been told that the front panels were pulled prior to disposal). Many of you will be familiar with Ralph Klimek and his amazing stories of life as a technician with these machines. He has some pictures of this particular frame, about mid way down this page on his site: http://users.monash.edu.au/~ralphk/burroughs.html Because I live close by, I was dropping in every so often to check up on both this frame, and a (smaller) VAX 11/780 sitting next to it. Because the Uni has quite a decent vintage computer display in place at it's Caulfied campus, I had felt comfortable that both machines were safe. On a relatively recent visit (a few months ago, late last year? I'm not quite sure as life is a bit of a blur at present) I noticed that both machines had gone, and that some renovations were taking place in the building. I felt that the machines must be safe but decided I should try and make contact to be sure (working in ICT for so long, I should have known not to trust an assumption), A few days ago I got a note back saying that the Uni had requested the builders to remove the B7800 chassis and dispose of it (the 11/780 was moved to the Caufield collection). Since then I've gone on a bit of a campaign to try and find out of the machine might still be sitting somewhere with the builder (or their sub-contracter). It's a very long shot, but in this case I think most here on the list would agree it's worth it? Apparently the scrap metal value would be quite low at the moment, and hopefully whoever has it has been too busy to deal with disposal yet (a long shot, as I said). I've managed to speak to numerous people both inside the Uni and the builder, but have realised from them that my enquiries now need to be pushed four ways - into two Schools within the Uni, and also two service departments.?My problem is that I'm attempting to get a startup software company off the ground, so time isn't something that I've got any of, let trying to push my way through contacting people within four different internal departments (and sitting through all the on-hold music, call transfers & drop outs). I don't think that the Uni wants this chassis at the end of the day.? Is there anyone who can attack this at a higher level? I'm happy to pass on relevant details to anyone who could help positively (I don't want to cause unnecessary aggravation by posting everything here, the people I've spoken to have already been as helpful as they can). If it's true that it is possibly one of the last existing CPU frames of the B5000 family, and if it went to one of the major Museums in the US as a result, that would be a great outcome (if it still exists at all). Regards Evan

10 years, 1 month

PDP-11/04 running CAPS-11

by mattislind＠gmail.com

During approximately one and a half year I have been restoring a little PDP-11/04 computer with a TU60 DECassette drive and a LA30P Decwriter. I have followed the trail of Lou and got it to run CAPS-11 as well as CAPS-11/BASIC. It has been an interesting journey to repair it and actually trying to use it give a glimpse of what it was like to develop software 40 years ago on a minimalistic system like this. Since it only has 8kW of memory the BASIC system uses overlays. It takes at least half a minute to load the runtime environment when you hit the RUN command - and then half a minute to get back to the editor again after running. Indeed patience demanding. I put together a webpage: http://www.datormuseum.se/computers/digital-equipment-corporation/pdp-11-04 and a short video when it runs: https://www.youtube.com/watch?v=EQsP444N5zQ /Mattis

10 years, 1 month

RD54 Stopped Spinning

by ard＠p850ug1.demon.co.uk

> I suppose that is possible, but not sure that would explain the dead stop, although I suppose it isn't impossible. I Bad connections rarely do anything you expect :-) > was nowhere near it when it happened. Do the signals I posted look right to you? Would you expect inconsistent > triggering on the scope on just one of the FET outputs? More seriously, have you tried swapping the FETs round to see if the dodgy signal goes with a particular transistor? -tony

10 years, 1 month

Altair Turnkey and some DEC stuff cheap

by jnc＠mercury.lcs.mit.edu

> From: B Degnan > I have one Altair turnkey (chassis only) and a bunch of DEC components > available from a lot of computers I picked up the other day. So I wound up with all the DEC gear from this (I gather the Altair is gone too), but I'm not at all sure I want the System Industries hard drives. (I assume there's at least one controller for them there, but all I know is what's in Bill's posting. :-) Is there anyone out there who'd be interested in them, if I decide I don't want them? Free (basically) to a good home (although if you can't do a pickup, we'd have to look into shipping). Noel

10 years, 1 month

Altair Turnkey and some DEC stuff cheap

by jnc＠mercury.lcs.mit.edu

> From: B Degnan > I have one Altair turnkey (chassis only) and a bunch of DEC components > available It sounds like Bill's mailbox is exploding... :-) Apparently the DEC stuff already has several people who are willing to take it. Noel

10 years, 1 month

Pertec OEM Sperry 1900/10 System

by ehogan＠unimetrix.com

We have the subject system in our New Jersey facility if anyone is interested. Early 1980's manufacture.

10 years, 1 month

SGI Indigo2 graphics options

by seefriek＠gmail.com

From: Jochen Kunz <jkunz at unixag-kl.fh-kl.de> > Similar: We had some Indigos in indogo color but with "CDC Cyber 910" > (yes, CDC as Controll Data Corp.) printing at the Unix-AG. Ha! Memories. I have a recycler friend who called me up one day having a line on a st00pid number of "CDC computers" for dirt. He thought maybe he could make a few dollars on machines from the Center for Disease Control. I took a look and realized they were rebadged SGIs from Control Data, workstations and servers. I hooked him up with some folks into that sort of kink and he sold each one for about 15 times what he paid for them. I bought a car and a really nice grill with what he kicked back to me for the intel and the hookup. Good times.

10 years, 1 month

hpdrive hpib

by marc.verdiell＠gmail.com

Bob Brown wrote: >Does anyone have experience with the hpdrive project? I do. I use a small board NI PCI card. Like this one: http://www.ebay.com/itm/National-Instruments-High-Performance-GPIB-interface -for-PCI-Model-PCI-GPIB-/221231586346?pt=LH_DefaultDomain_0&hash=item33826e1 c2a Works wonders. >I'm wondering if the following card might work with it: >http://www.ebay.com/itm/HP-Agilent-82350A-E2078A-PCI-GPIB-Interface-Card->/ 351361191725?pt=LH_DefaultDomain_0&hash=item51cec24f2d It won't. As you can see in the picture, it's based off the TI9914 which is specifically excluded from the compatibility list. Search National Instrument PCI-GPIB on eBay and there is a ton of these. The older large ones are less expensive than the newer small ones. Jay West wrote: > I had read somewhere that most PCI cards did not [work]. They do. But you need an National Instrument card based off the chipsets that Ansgar lists, because he wrote his driver for the NI chipset series. I use the relatively recent (vintage 2002) small form factor NI GPIB PCI card. Although he doesn't have it listed as tested, it is based off the TNT5004 chipset and works without any problems with his driver.

10 years, 1 month

Altair Turnkey and some DEC stuff cheap

by billdeg＠buzz1.com

I have one Altair turnkey (chassis only) and a bunch of DEC components available from a lot of computers I picked up the other day. I am looking only to recover expenses (truck and gas) and I don't want much. These are best for someone who has experience cleaning a "barn find" as this is where I got these items. The real "cost" will be the time needed to take apart these systems and clean thoroughly. I did not see evidence of any chewed wires fortunately, just nests, some urine staining, seed storage, etc. All of the computers were working maybe 20 years ago-ish but they have fallen into neglect. http://vintagecomputer.net/temp2/ Best offer for some/all, pick up only. Landenberg, PA. No I will not deliver to VCF. CONTACT ME HERE: http://vintagecomputer.net/contact.cfm - PDP 11/34 #1 (no serial card but otherwise populated) * - PDP 11/34 #2 (with Hard drives, racked, no serial card but otherwise populated) * - PDP 11/44 (mostly populated complete maybe) * - Tall rack with RK05 ** and hard drive for DEC 11/34 #1 - Altair Turnkey, chassis only. * asterisk key: * items contains/contained a rodent nest. ** I tried but could not extend from rack, rails rusted? NOTE - I will keep these items outside ready to be taken. They will be tightly covered with a new tarp, the weather should be nice for a while. That said, if you want these items held for an extended period I can't guarantee that they'll stay dry forever. Act Now! Bill

10 years, 1 month

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test-drb April 2015