test-drb October 1999

test-drb@ccmp.vtda.org

216 participants
748 discussions

Running a 220v computer in a 110v environment

by danburrows＠mindspring.com

The only safe way is to use a transformer that is correctly wired. US mains is 120 - neutral - 120. which gives 240 between the 2 hots. European mains are 240 - neutral. Both expect the neutral to be at / near ground potential. If you wire it to US 240 directly what was neutral in Europe will be at 120v. I have several isolation / step up transformers that I routinely use to accomplish this. You need to be careful how they are wired in order to have both primary and secondary tied correctly to neutral and the grounds MUST be kept separate >from the neutral to meet US electrical code. Dan -----Original Message----- From: Ram Meenakshisundaram <rmeenaks(a)olf.com> To: Discussion re-collecting of classic computers <classiccmp(a)u.washington.edu> Date: Thursday, October 07, 1999 10:19 AM Subject: Running a 220v computer in a 110v environment >Hi, > >Probably some of you have already done this. I have an equipment, a >parsytec xplorer, that runs a 220v. I got it from across the pond. >Since I am in the states and the power output is 110v, is there any way >for me to run this without getting a transformer to pump it up to >220v??? Unfortunately, the parsytec doesnt convert automatically like >PC and laptops of today. In my apartment, there is a funny looking plug >next to out AC. I remember somewhat vaugely that it is actually 220v. >Is this true??? How did you guys solve this problem???? I want to get >a good solid response before I blow up the machine :-) > >Ram > > >-- > > ,,,, > /'^'\ > ( o o ) > -oOOO--(_)--OOOo------------------------------------- >| Ram Meenakshisundaram >| Senior Software Engineer >| OpenLink Financial Inc >| .oooO Phone: (516) 227-6600 x267 >| ( ) Oooo. Email: rmeenaks(a)olf.com > ---\ (----( )-------------------------------------- > \_) ) / > (_/ > >

25 years, 2 months

Dangers of shifting classic computers (was: AT&T PC 6300 Plus Unix box)

by daniel＠internet.look.ca

-----Original Message----- From: Peter Pachla <peter.pachla(a)vectrex.freeserve.co.uk> To: Discussion re-collecting of classic computers <classiccmp(a)u.washington.edu> Date: Thursday, October 07, 1999 12:17 PM Subject: Dangers of shifting classic computers (was: AT&T PC 6300 Plus Unix box) >Hi, > > >....This machine will alwas have a special place in my collection > >though, since it is so heavy I sprained a muscle in my back while > >lifting it so bad that I needed several weeks of therapy to cure. > >One of the hazards of the old computer collector... > >Quite, I've managed to injure myself a number of times shifting medium/large >sized machines over the years. > >I trapped a nerve in my back both times I shifted my old PDP-11/23+ (in an >H960 cab with a pair of RL-01s). And please, believe me, shifting a PDP-11/34 >by yourself is NOT a good idea....my back muscles still wince at the thought. > >Also managed to strain a couple of back muscles when I moved my SGI 4D/70GT >into the house. There were two of us moving that beastie and we'd taken all >the boards out of it first (they're about the weight of my 11/53 on their >own). > > >Not to mention that I've been in agony for a week now with a trapped nerve in >my shoulder. But then again there really was no way to disassemble that "Space >Invaders II" machine which I was moving out of the house.... > >Anyone else hurt themselves, lost limbs etc??? ;-) > > Quite a few times. When I was younger I would move RK05 drives all over the place by myself - killed my lower back. To this day I have bad back problems. My worst injuries are: RK05 / PDP 11/34 (no help) - bad lower back. Honeywell 316 - cyanide poisoning, was in the hospital, wished I was dead for a good 4-5 days as my insides were eaten out. Honeywell 316 - The scrap dealer (Wayne Borer) that got the unit for me brought it to the house when I was rather young. They got the entire case (included H316, fixed head DH, interface bays, air conditioner) to end of the truck when it started to fall. It fell on his NUTS! 3 guys (including my dad) held the case away from killing him. He rolled on the ground for at least 30 minutes in extreme pain. He never did have any kids after that. Honeywell 316 - Rack mounted on a flimbsy case, fell over one night and badly damaged the headboard on my bed. (kept it in my bedroom) H-11 with 2 RK05s and a bunch of other heavy mainframes - Broke the shocks in my dads caddy on the way home from athe Rochester Hamfest, scratches and back pain from making it fit. There have been more painful memories but I can't remember them all. The cyanide poisoning was the worst. > TTFN - Pete. > >-- >Hardware & Software Engineer. Sound Engineer. >Collector of Arcade Machines, Games Consoles & Obsolete Computers (esp DEC) > >peter.pachla(a)virgin.net | >peter.pachla(a)vectrex.freeserve.co.uk | >peter.pachla(a)wintermute.free-online.co.uk | www.wintermute.free-online.co.uk >-- > >

25 years, 2 months

Next steps (was Re: pdp 8/e)

by ethan_dicks＠yahoo.com

--- Chuck McManis <cmcmanis(a)mcmanis.com> wrote: > Yup, that would be the DEC "standard" three loop current loop interface. > (Tx loop, Rx loop, reader-run loop). Is there a picture of the "standard" 20mA connector with pinout? I want to test my ASR-33 up against a VT220 and I need at least to make a pin-swabbing cable if I don't need a 12V power supply, too. > >Yep. Unfortunately I dont have any peripherals. Except the one RL01, and > >apparently I dont have an interface board for that. > > I don't believe DEC made a Quad RL controller. I've only seen the M8433 > which is a hex wide RL controller that plugs into the PDP-8/a. That is the only RL controller I am aware of. OTOH, I like it a lot. I got one when I could not get RK05 drives, but I could get RL01 drives for around $100 plus shipping (over ten years ago). At that time, RL02's were still many hundreds. > >If the core memory doesnt work out, is the MOS memory actually affordable? I can't say for quad MOS. I've only got hex MOS... I haven't paid over $50 a board for any of it. > >Anyone willing to tell me some PDP parts suppliers that may have some > >interface boards, I have bought much from Continental Computers including an RL8A, KT8A and 128Kw memory board (MM8A-?) but you have to know by handle number what to ask for. I rattled off a list of boards and they only had two or three of the ones I was interested in. > > like whatever I need to hook up that RL01 (what exactly > >is a RL01 anyways). An RL01 is a 5Mb, single platter, embedded servo-style, removable drive. The RL02 is a 10Mb version of the same technology. They aren't all that fast, but they were plentiful, being available for the -8, -11 and various flavors of VAXen. IMHO, there is much less to maintain than than with RK05s. The OS/8 driver for the RL01 defines three logical units per physical drive, 40%, 40% and 20% of the capacity, but the third unit is slower because it fills the nooks and crannies around the first two units. It's because of a physical device size limitation in OS/8. > Maybe I should be looking to add floppy drives, etc. Floppies are nice if you have a stack of media with stuff on it. I have a few games and such. I'd like to be able to back them up to a modern machine and cut a CD-ROM of the disk images. To that end, I've just extracted a Tandon TM-848 floppy from my DataRam Q22 box and need to see about a power harness (six pin, H-shaped) and a 34<->50 pin cable to hook it up to an old box to do media conversion. > >OR, are people using IBM's as a terminal, and running some program that > >pretends to be an attached paper tape reader/punch unit? That might do > >for starters, though its not anywhere near as satisfying. If you didn't have a teletype, I guess a TTY emulator on a PC would be a way to go, but I don't know of any punch/reader emulating software, per se. I guess you could adapt ProComm or something like it that can upload and download data over the application. > >From there you have several choices, perhaps the simplest is the ASR33 with > paper tape software. As attendees to VCF can attest, it makes a loud but > somehow comforting ratcheting sound to hear FOCAL or some other system > being loaded at 10 CPS. On Highgate there is software for RX01's (OS/8 et al) It's not comforting to load papertape basic and Star Trek at 10cps... that's a *lot* of tape. I was glad to have a highspeed reader on the 12Kw -8/L. > Lots of fun ahead, > --Chuck For sure! -ethan ===== Infinet has been sold. The domain is going away in February. Please send all replies to erd(a)iname.com __________________________________________________ Do You Yahoo!? Bid and sell for free at http://auctions.yahoo.com

25 years, 2 months

Apple //gs for sale

by siconic＠jasmine.psyber.com

Here is a non-profit organization trying to unload what looks to be a very nice and relatively complete Apple //gs system (with boxes!). I'd say a fair price for all this (and taking into account that this is a non-profit in need of cash) is $300 + shipping. Just a suggestion. Please reply to the sender. Reply-to: mwsmn(a)aol.com ---------- Forwarded message ---------- Date: Wed, 6 Oct 1999 17:18:08 EDT From: Mwsmn(a)aol.com To: vcf(a)vintage.org Subject: Question Hello, I have a 1988-1987 Apple 2 Gs With The extended RAM installed. With the historical value, how much would the system resell at? -APPLE CPU -14" MONITOR -KYBRD/MSE -250 SOFTWARE TITLES -ORIGINAL BOXES FOR SOFTWARE AND COMPUTER COMPONENTS -IMAGEWRITER 2 COLOR REFURB PRINTER -ALL ORIGINAL DOCUMENTATION We are a nonprofit organization. We are in need of a new system. We look forward to your response. (If you can, please tell us a place to sell it. USA only please) Thanks For Your Time. Hope You Can Help. Also, It's great to find an old-computer show. These wonderful machines brought us to where we are today. Glad you are showing yesterdays technologies! Sellam Alternate e-mail: dastar(a)verio.com ------------------------------------------------------------------------------- Puttin' the smack down on the man!

25 years, 2 months

Dangers of shifting classic computers

by steverob＠hotoffice.com

> > Not to mention that I've been in agony for a week now with a trapped nerve in > my shoulder. But then again there really was no way to disassemble that "Space > Invaders II" machine which I was moving out of the house.... > > Anyone else hurt themselves, lost limbs etc??? ;-) About 10 weeks ago, I was working on the drives on my HP9000 and severly sprained my lower back. I have been weight training for many years and was lifting correctly. A little turn in the wrong direction and OUCH!!! When asked what happened, I told everyone at work that I hurt myself installing a hard drive in my computer. Most of the guys laughed and called me a wuss. :-) BTW: I'd guess those drives weigh about 125# each. Steve Robertson -<steverob(a)hotoffice.com>

25 years, 2 months

Help wanted in dumping EPROMs

by edick＠idcomm.com

I have an old multibus-1 board from "Little Machines" on which the 186's and '286's among other things are wired backwards and soldered to the board because the original Intel data sheet didn't distinguish between the top and bottom of the JEDEC "A" package which is a leadless ceramic chip carrier of the type often seen in early PC/AT types. The board is so busy you can barely see any of the surface, and it's much the same on what ought to be the wiring side, as there are oodles of passives and other small-outline parts, I'd say as many as 1000, on the "back" of the board, since there wasn't room for anything more on the "front" where there are well over 100 DIP packages of various sizes. This solder-in of the leadless chip carrier package was done interestingly enough, in that the pins from an LCC socket were aparently extracted and soldered, one-by-one, to the board and the device inserted UNDER them in order to allow them to be soldered from the top. It can happen to anyone, I guess. Dick -----Original Message----- From: Tony Duell <ard(a)p850ug1.demon.co.uk> To: Discussion re-collecting of classic computers <classiccmp(a)u.washington.edu> Date: Wednesday, October 06, 1999 1:14 PM Subject: Re: Help wanted in dumping EPROMs >> >> Yes indeed! The data sheets for the two parts will answer all the >> questions. All one has to do is to stay awake. I wouldn't make such a >> statement if I didn't know of instances where one has gone to sleep . . . >> that's one who shall remain nameless . . . > >Make it 2, OK :-). I very nearly wired up a transputer socket >mirror-reflected because one book showed the chip from the top and >another showed the socket from the bottom. I caught the error just in time... > >-tony >

25 years, 2 months

FW: Free to good home: Byte Magazine 1993 - 1998

by kyrrin＠bluefeathertech.com

If anyone would like a complete collection of BYTE mags from 1993 until the last issue in 1998, drop an E-mail to the fellow below. He's just looking for a home for them. -=-=- <snip> -=-=- On Thu, 07 Oct 1999 12:19:07 GMT, in seattle.forsale.computers you wrote: >>Includes the last historic issue published in July 1998. >>This i s a collector's set. My wife prefers basement space to >>history. I would rather see someone enjoy the collection >>than turn it in for land fill. >> >>Any takers? >> >>Please respond by e-mail. Remove % from the address >>before pressing SEND. Actual address is tcox(a)jps.net -=-=-=-=-=-=-=-=- Bruce Lane, Owner and head honcho, Blue Feather Technologies -- kyrrin (at) bluefeathertech [dot] com Web: http://www.bluefeathertech.com "...No matter how we may wish otherwise, our science can only describe an object, event, or living thing in our own human terms. It cannot possibly define any of them..."

25 years, 2 months

S-100 Bus

by edick＠idcomm.com

please see embedded comments below. Dick -----Original Message----- From: Allison J Parent <allisonp(a)world.std.com> To: Discussion re-collecting of classic computers <classiccmp(a)u.washington.edu> Date: Wednesday, October 06, 1999 9:21 PM Subject: Re: S-100 Bus ><If you're an S-100 user, particularly if you have experience in bringing ><up a system from totally dead to totally alive, I'd certainly like to ><see what your impression of your needs from such a device might be. > >I've brought up several IMSAIs, Altairs, NS*, Netronics explorer 8085, >several mongrels and my multi-CPU s100 crate. > I've also brought up a number of S-100's and SBC's, not to mentions systems on the MULTIBUS-I. The only case in which I've used a front panel has been the one MULTIBUS-user-client I had once whose SW types thought it would help. I doubt that it did, but it was a fun job! > >Front pannel systems were rich enough to accomplish the task once the FP >was known working or nearly so. Often the problems were dirty switches, >broken wires, failed oneshots or maybe a bad LED. Other problems were the >older boards that didn't like Bus pins 20 and 70 (protect/unprotect). > >Must haves: > > ability to display memory > ability to write to memory > Start, stop and single step the CPU Those go without saying. After all, this is supposed to be a diagnostic tool. >Most front pannel systems (alatir, Imsai, Ithaca intersystems, PDA-80 have >the basic resources. A scope may be needed if there are timing issues >or one shots that are drifted off. > >The non front pannel systems required a FP that could be plugged in. the >easiest way was a a minimal CPU (Computime SBC880) that can drive the bus >but is otherwise self contained. That and a terminal is as good as a front >panel (better). I agree, except that I belive that your PC-compatible would make an even better FP substitute, with its nearly 1 GHz processor, 1GB of RAM and several 3-doz-GB HDD's. Moreover, since it can not only load programs and monitor their execution, clock-tick-by-clock-tick, and disassemble unfamiliar code in real time, generally waiting for the resident processor to catch up, it has potential not yet exploited. You can use it for logic analysis, signature analysis/failure detection, code verification, profiling, etc. It's just another tool, but if it can be sold for less than IMSAI's FP, then it's not only an improved tool, but less costly, too. Since you can repetitively stimulate the S-100 in a short loop, you can easily address signal quality issues previous too slippery for most folks. You can look over the processor's shoulder or you can take him out of the loop and run things yourself. When you've narrowed the problem you have down to a small set of signals, you can poke around with your 'scope to see that all's as it should be. >The multi-cpu system needed more as the CPUs were not commercial units >IE: they never worked before so they had to be debugged first and that >required a bus logic analyser (capture bus state 1024 cycles deep) that >could trigger on specified conditions. This was needed to look at the >interaction of the many cpus and DMA devices. Once the system could run >code predictably (could still crash but reset to rom monitor was reliable) >The bus analyser was almost by un-needed. I never used a front panel until I was asked to build one for a multi-processor system on a VERY extended Multibus-I. That was fun and profitable, but wholly unnecessary, I felt, since all the processor boards were completely self-sufficient with the exception of mass storage, and since the CP/M image was in ROM, it didn't take long to boot, either. >A simple logic probe was the single common tool besides a front panel or >its analogue. A multi trace scope was handy for Altairs (too damn many >one-shots!) and other system where the problem was logic that was damaged >from lightining (my old NS* system). > I've normally addressed lightning damage with a call to the insurance company, though they usually don't respond promptly. The procedure for socketed boards is to take the parts out and test them in a tester. Most prom programmers can do that. I really don't see how a logic probe can help you until you've narrowed the problem down to a single board. What's more, it's common enough to have several boards which work correctly in a system that doesn't. Sometimes they just don't work and play well with others. CompuPro boards were famous for this. They often wouldn't work with other boards from CompuPro. They weren't alone in this, but their idea of interoperability was that MOST of the boards in a system which they sold would work together. Their excellent marketing and advertising made them the main force behind adoption of a standard too weak to work, and too vague to provide guidance. They, more than any other maker of S-100 stuff ignored whatever parts of the standard that it suited them to ignore, and they weren't alone. The problems of this sort are exactly the sort I'd seek to address with a bus probe. What's more, there are few tools which will automatically allow you to find inadvertent connections between signals, say, because of a mis-jumpered board, or such, or to find that what one board maker uses for signal is GND to another. > >Allison > > > >

25 years, 2 months

Site update and Compaq 486

by jolminkh＠nsw.bigpond.net.au

r. 'bear' stricklin wrote: >The very first EISA machines were brand new in June of 1989, and were >powered by 25 MHz 80386 CPUs. I used to have a copy of the Byte in >question, which also featured MCA clones. I wish I knew where it got to. > >I don't think the first machines using 33 MHz 80486 CPUs were released >until sometime 1991. I don't think its the Byte article you mention, but the May 1990 Byte goes into a comparison of EISA and Microchannel. Says the first EISA machine was a HP Vectra 486 and talks as if the Compaq Systempro was next. Hans

25 years, 2 months

Still Looking for DEC CR11/CM11 Card Reader!

by mcquiggi＠sfu.ca

Hi Group: A repost, just in case anyone missed it: > > Hi Gang: > > I'm interested in finding a card reader for my pdp-11 machines. There was > one advertised as available earlier this week, unfortunately it has been > claimed. > > The CR11 and CM11 models are what I'm looking for - they're a desktop > variety that would work nicely with my current machines. > > Anyone out there have one they will part with? > > Kevin --- Kevin McQuiggin VE7ZD mcquiggi(a)sfu.ca

25 years, 2 months

← Newer
1
...
58
59
60
61
62
63
64
...
75
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 October 1999