test-drb April 2011

test-drb@ccmp.vtda.org

184 participants
276 discussions

Wanted: WD1002-HDD docs or Teac SD-520U help

by mbbrutman-cctalk＠brutman.com

I recently received a PCjr add-on which is so unusual, it felt like Christmas. But as always, it needs a little TLC. This is an expansion chassis made by an outfit called "Legacy Technology" in Nebraska in the mid to late 80s. The interesting part of the chassis is a hard drive controller card and hard drive. PCjrs only had hard drives if you bought a 3rd party controller, and they were all pretty hackish. The drive is a 20MB Teac SD-520U and it is very flakey - I am getting data corruption almost all of the time. The corruption seems random; this drive might just be tired. I've low level formatted the drive twice. The controller BIOS supports INT 13, Function 7 (Low Level Format). It's not helping. Since the drive is probably not usable, I'm trying to figure out how to substitute in another drive. Examination of the BIOS extension shows that the controller supports 3 types of 20MB drives and 1 type of 10MB drive. I have 10MB drives that I can use, but not another 20MB drive. This is an XT class controller so I'm expecting to find some jumpers to set the drive type, but they are eluding me. The controller is actually a two part affair - A small amount of logic with the system BIOS extension on it, and then a WD1002-HDD board. The WD1002-HDD board mounts to the underside of the hard drive and then connects to the hard drive using the familiar 34+20 wire ribbon cables. It looks like it is capable of controlling three separate drives; it only has one 34 pin connector, but it has three 20 pin headers, one of which is in use. Does anybody have docs for the WD1002-HDD? If so, where do I find the drive type jumpers on the board? If I can't figure the controllers out I'm going to be looking for a similar drive. I suspect the trusty ST-225 works - the geometry is the same. Regards, Mike

14 years

Good-condition IMSAI for sale

by evan＠snarc.net

We in MARCH are selling the following IMSAI 8080: http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&item=270739896050 Proceeds for this system are NOT going to our club, but rather to the widow of a local computer reseller who died in an industrial accident recently. Our club was asked to fix up the computer and sell it on her behalf. - Evan Koblentz and Bill Degnan

14 years

CMS disk drive?

by wdonzelli＠gmail.com

I have encountered an old 14" disk drive - it looks like it is probably a clone of an IBM 2314. It does not look like a 2314 at all (it is plain blue box with, that sort of looks like a 2311, but with more heads), and no tag at all. The drive interface uses that goofy connector that the late 60s IBM drives standardized on, for talking to the control units. The boards all have "CMS" stamped on them. Any ideas? Was CMS, whoever they were, one of the early clone companies? -- Will

14 years

Selectric speed and durability (was Re: Retro Atari 400 looking Keyboard)

by ethan.dicks＠gmail.com

On Thu, Apr 21, 2011 at 2:47 PM, Fred Cisin <cisin at xenosoft.com> wrote: > On Thu, 21 Apr 2011, Brian Lanning wrote: >> My mom was a secretary. ?She had an IBM selectric. ?World's loudest >> typewriter. ?She could type 90wpm on that thing. ?Oh man, what a >> sound. It sat on a foam mat to try to absorb some of the vibration. ?I >> used that for my papers until I got an original IBM 5150 and my school >> got a much of Apple 2Es. > > Rated top speed for the mechanism was 14.8 characters per second (about > 150 WPM). ?But a 150 WPM typist (yes, I've met some!) would have bursts > substantially higher, and selectrics would come apart. I do not know precisely how fast my mother could type, but her Selectric sounded like a machine gun when she got going. She never had one "fly apart", but she did wear out more than one unit from 8-10-hour-days of multi-page-carbon-set production work (final copies of court transcripts). She was paid by the page, so long stretches of error-free typing was the only way to make a decent wage. At one point in the early 1980s, her machine broke and she took it to a new repair shop in town. The tech was puzzled at the wear he observed during the triage until he watched her type to test out the freshly-repaired unit. As she banged away at a high rate of speed for a full page, the tech nodded and said to her, "you and I are going to become good friends". He was right. (Our 32K PET shared the home office with the Selectric. One afternoon when I was noodling around on the PET and she was deep in production mode, during a pause in the clatter, I remarked that someday soon, she'd be doing all of that "on one of these" (meaning a computer, not specifically a PET). She laughed. Less than five years later, she switched to 512K Macs and an Apple LaserWriter I). > At work, somebody succeeded in running one at 300 baud. ?Briefly. > That was discontinued when the "golfball" went flying into a sheetrock wall. Wow. Who knew full-face-shields were needed in an office environment. -ethan

14 years

I wanted 100 pieces of Windows NT4 with license

by curador＠museudocomputador.com.br

Please send a email -- * * * * <http://www.floy.com.br/painel/painel.php> *in English: http://museudocomputador.com.br/homeingles2.php V?DEOS SOBRE O MUSEU, RECICLAGEM E COTAS. * *SEJA UM PARCEIRO DO MUSEU, COMPRE UMA COTA DE R$ 250,00 E LEVE O MUSEU PARA SUA ESCOLA 2X AO ANO. LIGUE J? 11 4666-1338 OU 4666 7545 COM JOS? CARLOS VALLE* *V?DEOS SOBRE O MUSEU E PARCERIA ASSISTAM:* Olhar Digital http://www.youtube.com/watch?v=EIVcCDl4LnI http://www.youtube.com/watch?v=-yLggafyqkk O Museu em Recife fev 2011: http://www.youtube.com/watch?v=-tpEA3xlXyc O Museu no Jornal Nacional, notem que o Museu teve o maior tempo: http://www.youtube.com/watch?v=RJEIuMcYtzA TV Gazeta http://www.youtube.com/watch?v=OaxqyqgJakA NO site do Museu: http://www.youtube.com/watch?v=OKgUCeoXZ8c *MUSEU VIRTUAL EM 3D:* *http://www.youtube.com/watch?v=gQ4uyVBW-tw* o Curador filmou a m?quina do Babbage ao vivo em 2007, na visita ao maior Museu do Mundo de Computadores, o Museu do Computador tem parceria com eles, e este v?deo mostra uma pe?a rara ao vivo. http://www.youtube.com/watch?v=NsI0rtM2ZYw Degiratti Link: http://www.youtube.com/watch?v=Rl7GEcY8DRc&feature=related IN English: http://www.museumprofessionals.org/forum/tell-us-about-your-museum/7015-mus…

14 years

Lisa sighting at Notacon

by keithvz＠verizon.net

So I attended Notacon, and some people may be interested to know that there was a Lisa there brought by the CMU Computer Club. They hacked together a demo on it, which was pretty decent given the clock speed, etc. They claim "first lisa demo ever." --- you know how that goes around here! :) The demo concluded with the apple logo in COLOR, which they did by translating the brightness-level information into color on the FPGA board. They used an fpga development board to bring digital video signals in off the chips, and frame buffer it and output to an HDMI output port. They didn't actually scan convert it, but left it at its native resolution, which was something weird. Like 700 x 300 or something? (quick google says 720 x 364) When pushing them for more answers on details of their hacked together video solution, and ideas for scan converting --- they clammed up, and said that since they will be offering a commercial product at some point in the future, they couldn't talk about it. Weren't going to document it publicly, post it online, etc. I suppose it's not too surprising that college kids don't understand the difference between raw ideas & prototyping vs executing and marketing an actual product. I just found it disappointing that it happened at a place where the fundamental point of getting together is to share information. I guess they consider sharing a one-way street. Keith

14 years

Wanted: WD1002-HDD docs or Teac SD-520U help

by tshoppa＠wmata.com

Eric writes: >Fred Cisin wrote: >> "trusty ST-225"?? > Well, as compared to some brands, yes. JTS comes to mind, though it > wasn't contemporary with the ST-225. Most of my suffering with MFM drives happened at the upper end of the cost/complexity spectrum. Looking back 20 years I in fact have good respect for the simpler of the MFM drives and the ST-225 is an example. Maybe my expectations were just lower for a drive that didn't cost $4000 (list price of a XT-2190). But it's also quite true that ST-225's didn't crap out at the rate as the much more expensive MFM drives and for that I have to really give them some credit. Tim.

14 years

OT: vacuum tube question

by evan＠snarc.net

Can someone here please explain to me, in ** simple English **, the difference (in usage, not in how they work) between a "control grid tube" and a "barrier grid tube" ... ? I tried Googling but that led to me being more confused, not less. :)

14 years

S-100 Serial IO boards available

by lynchaj＠yahoo.com

Hi! There are bunch of S-100 Serial IO boards left so if anyone would like one or more please let me know. John has a nice description of the board here: http://s100computers.com/My%20System%20Pages/Serial%20IO%20Board/Serial%20IO %20Board.htm These are respin PCBs which resolve all the minor issues from the original release and the board is 100% without any modifications. These are generic IEEE-696/S-100 serial IO boards with dual serial ports, optional USB, and optional voice synthesizer support. There are also some parallel pins available. They are available for $20 each plus $3 shipping in the US and $6 elsewhere. If you have questions you can contact me or ask on the mailing list http://groups.google.com/group/n8vem-s100 Thanks and have a nice day! Andrew Lynch PS, although these are home brew PCBs you can use them in either building your own S-100 from scratch, restoring/repairing a vintage system, just adding them to an already working system for more IO.

14 years

IMSAI 8080 for sale, for a good cause

by billdeg＠degnanco.com

MARCH is selling the following IMSAI 8080 http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&item=270739896050 Proceeds for this sale will go to the widow of a veteran Trenton Computer Festival exhibitor whose husband died in an accident. She donated her husband's collection to the Mid-Atlantic Retro Computing Hobbyists, and asked that we sell one nice system from that lot to help her financially. Bill

14 years

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test-drb April 2011