test-drb November 2001

test-drb@ccmp.vtda.org

247 participants
886 discussions

by pete＠dunnington.u-net.com

On Nov 20, 0:53, Tony Duell wrote: > > I've been cleaning up my recently-acquired PDP-8/E, and I've had to remove > > the plastic foam from the inside of the lid, which was fairly horrible. > > Yes, that's a very common problem... Makes a right mess on a the backplane... This hadn't reached the completely crumbly stage, but it did smell of cat :-( > I have never seen conductive foam used on PDP8/e machines. There's > nothing particularly static-sensitive in there anyway (the CPU is all > fairly large-junction bipolar chips (TTL, etc). Mine just had the normal > brown foam throughout. > > Since you can put options with top connectors anywhere in the backplane, > there would seem to be little point in having special foam over the front > slots only. > > But the leakage on conducive foam is not that high, and I doubt that > using it would cause many problems (TTL inputs are fairly low impedance). > It might have an effect if used over core memory units, but actually I > doubt it. I didn't really think it would make much difference, but I can clearly see the impression made by the connectors for the core stack, which is reputedly not working. The machine had modern semiconductor memory in it when I got it -- the 1995 board I mentioned in another post -- and I've not tried the core for myself yet. -- Pete Peter Turnbull Network Manager University of York

24 years

sought: SunPC 3.1b software

by red＠bears.org

I just found a SunPC Accelerator DX in a box of junk at a recycler's. Does anybody have a copy of SunPC 3.1b so I can try to use this on my Solaris 1.1.2 box? Supposedly it was distributed on CD; a disc image or a copy of its contents would be more than sufficient. TIA ok r.

24 years

What is a RL02K-DC?

by kurok002＠tc.umn.edu

I recently found a RL02K-DC cartridge in storage here at work. I was just curious to know if they are worth anything today? Are they still being used?? -- University of Minnesota Cancer Center 590 CCRB MMC 494 420 Delaware Street S.E. Minneapolis,MN 55455 E-mail:kurok002@tc.umn.edu Phone: (612)626-4323 Fax:(612)624-3913

24 years

H7140 PDP 11/24 Power Supply Advice

by cube1＠home.com

I have had a PDP-11/24 for some years, working just fine (last time I had it on was about last May). Yesterday it decided not to work. Looks like the H7140 supply. The +300V on the voltage doubler is there, but the +13V in the Bias/Interface board reads about +7V. I suspect this is central to the problem. (The +12V Bias is also reading about +7V). When I turn the console power switch, I can hear the contactor in the power control unit in the rack, so I don't think it is the switch itself. When I flip the breaker on, I can hear a "chirp" as though an oscillator starts up. If I flip the breaker off, then about 10s later I can hear the chirp of an oscillator shutting down. Any words of advice? Does anyone have a technical description of the H7140? I have schematics (and can read them at the component level), but power supplies are hardly my strong point -- it would be useful to have some description of just how this animal goes thru a power up sequence. Plus, blind diagnosis will be slow -- there aren't any test points, and one needs to make sure the +300V from the doubler has been bled off before yanking cards to solder test tails at strategic points. It would be helpful if someone could give me some guidance so I knew more about how this thing works. Jay Jaeger --- Jay R. Jaeger The Computer Collection cube1(a)home.com visit http://members.home.net/thecomputercollection

24 years

Qbus & Unibus cards avalable

by Innfogra＠aol.com

I have the following Qbus & Unibus card that I want to offer to the list first before offering them on ebay. Please contact me off list at: whoagiii(a)aol.com Dilog MQ696 - This is a current 22 bit Disk Controller Qbus card. It is a 20 MHz ESDI controller for two drives. It also supports two SA450 floppy drives. It supports RX33/50s and MSCP. It is a nice looking design. M5903 Drive Transceiver M7607AP/AH MS630A 1 Meg MicroVAX II Memory - Have 2 M7946 RXV11 LSI11 RX01 Controller M7940 Serial Line Unit M7941 DRV11 16 bit Parallel Line Unit M8029 RXV21 LSI11 RX02 Controller M8186 Rev 202 D0 11/23 CPU M8958 TM78 Translator Unibus - Tape? M9202 Unibus Connector Inverted have 2 M9400 YE LSI11 Ref Boot Cable Conn Netcom NDLV-11 700 0055 MDB DRV11C Program I/O module Plessey 705113-100B Looks like a three serial port card Sandwich board set which occupies 2 sets of slots Andromeda Systems MSI11-2 2 serial port card handwritten serial numbers Have 2 Andromeda Systems MSI11 4 serial port card Rubber stamp SN 304 Codar Tech Has three batteries so I think it has clock functions. There is a 34 pin connector and a 10 pin jumper block? Digital Pathways TCU - 50 Real Time Clock card settable to normal or leap year Address-76077X Don't know its 2000 compatibility. Feel free to ask questions, preferably off list. I have pictures if needed. Paxton Astoria, OR

24 years

Slightly OT: Atari 2600s game collecting on "Antiques Road Show" on PBS TV

by claudew＠videotron.ca

Its not computer collecting on TV but very close... I tune in to PBS antiques road show (that TV show that goes around US and Canada towns and people bring their antiques to get them evaluated and info on them...) tonight and there was a short (2 mins?) segment on Atari 2600 cart collecting and they showed some examples of sought after carts...and some "values"...explaining this was very "hot collectibles" Do they know about computer collecting also? Claude http://www.members.tripod.com/computer_collector

24 years

Intel C8080A chip brings $565 on EBAY

by ajp166＠bellatlantic.net

That only applied to some of the darker ceramics and early parts were the white. They still had to remove or reduce the gold used in the bond wire and lead frames even for plastic. What drove the price of ceramic way up is ram and cpu prodution rates really jumped up from 1978 to 1984 and the production of ceramic packages could not keep pace. Plastic was always used for ram, and lower in cost. The problem was the early gray silicone plastics were far from hermetic. There would be several generations of the black stuff in an attempt to make the plastic less absorptive of moisture while trying better methods of passivating the die. Then there was the matter of disapating the heat. Even as late as 1984 the failure rates for the D416/4116 dynamic and 2114 and 2167 static parts was noteably higher for plastic than ceramic. I use those cases as they were mature parts by then and still plastic was viewed as less reliable though far lower in cost. Allison -----Original Message----- From: Bob Shannon <bshannon(a)tiac.net> To: classiccmp(a)classiccmp.org <classiccmp(a)classiccmp.org> Date: Monday, November 19, 2001 10:22 PM Subject: Re: Intel C8080A chip brings $565 on EBAY >In my experiance, very early chips used a purple ceramic with a high thorium >content causing the distinctive color. Unfortunatley, this thorium emits low >level >particles that cause soft errors, which became apparent in the early days of DRAM. > >This drove a change in ceramic processing and costs, pointing the way towards >todays plastic packages. > >Sellam Ismail wrote: > >> On Mon, 19 Nov 2001, John Galt wrote: >> >> > As far as the color, chip collectors refer to that color chip as >> > "purple". If you look at it next to a normal "gray" CerDIP, you can >> > see the difference. Besides, it would not have mattered had it been >> > black. The fact is, it's not the white/gold color of a normal Intel >> > C8080A. The printing on the chip is also somewhat different. My >> > guess is it's a late run C8080A that was put in the same package they >> > used for some of the later C8085AH's. >> >> My questions is: why does this matter? Will researchers 50 years from now >> find the Purple one useful for any sort of study? What makes the Purple >> one special beyond just being a pretty if not questionable shade of >> purple? >> >> Sellam Ismail Vintage Computer Festival >> ---------------------------------------------------------------------- -------- >> International Man of Intrigue and Danger http://www.vintage.org >

24 years

Slightly OT: Atari 2600s game collecting on "Antiques Road Show" on PBS TV

by mythtech＠Mac.com

>I tune in to PBS antiques road show (that TV show that goes around US and >Canada towns and people bring their antiques to get them evaluated and info >on them...) tonight and there was a short (2 mins?) segment on Atari 2600 >cart collecting and they showed some examples of sought after carts...and >some "values"...explaining this was very "hot collectibles" And what were some of the wanted carts? Not that I will ever part with any of mine, but it is always nice to know if you have something of monitary value (although, in my case, most of it will be "I had that!", since a "friend" walked off with most of my good ones years ago... kind of like all the first series star wars action figures I blew up with firecrackers in my youth) -chris <http://www.mythtech.net>

24 years

OT: paging MAC expert(s) --- What's a Performa?

by mythtech＠Mac.com

>I can't think of a way for a virus to jump onto a disk on a Mac simply >by the disk being there, without any virus-infected program >running. Unless a virus has attacked the Finder or the OS itself, >which is a possibility, I suppose. WDEF could do this, but it was rendered dead by System 7 (it infected the System 6 and earlier desktop database, so when a disk was inserted, it could spread to any uninfected desktop databases) >But even then, the virus can't jump *off* the disk onto a previously >clean system without running something from the disk, and that won't >happen unless you explicitly tell it to. If there's some way for that >to happen on Windows, then Windows is definitely more virus-friendly! Auto-Start worms, but then, you are really sort of running something off the disk (the worm), and these can be stopped by turning off the auto run on insert in the QuickTime control panel. -chris <http://www.mythtech.net>

24 years

Slightly OT: Atari 2600s game collecting on "Antiques Road Show" on PBS TV

by Innfogra＠aol.com

In Oregon it is on in 40 minutes, at 8:00 PM PBS. I look forward to it. Paxton Astoria, OR

24 years

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test-drb November 2001