test-drb May 2009

test-drb@ccmp.vtda.org

204 participants
322 discussions

by spedraja＠ono.com

Yesterday I installed some CP/M stuff available for the AltairZ80 simulator of SIMH. I am checking the use of the last version of the simulator from one DEC VT220 plugged in the serial port of my laptop. And I checking in essence the PDP-11 (with Unix) and Z80 (with CP/M, MP/M and Oasis) simulators In one of the virtual disks of CP/M exists a copy of the Eliza basic program. I tried it using the MBASIC interpreter. Very funny but interesting as an historical piece of software and as what the program do by itself. But the most funny thing was to check what happened when I show the program to my daughter and son (both under eleven years old). Half and hour later I need to obligate them to close the program. Absolutely addictive. And even more when I expleained them (in simply words) some aspects related with the program. Later, I encountered myself thinking about the evolution of the games, the programs, the artificial intelligence and the computing in general during >from the epoch of Eliza (or before) ot our days. And what can do a good piece of code against some excess of our days in the computing field. Kind Regards Sergio

14 years, 11 months

law enforcement assistance w/paper tape

by shumaker＠att.net

Help! Several months back I posted a request to the list seeking assistance in creating some examples of paper tape media for use by a law enforcement officer wishing to use them in a class he teaches. The course is about computer forensics but for perspective, he does a segment on various types of media with examples. At the time, a list member responded and offered to assist but apparently wasn't able to help... not sure what happened but the officer contacted me again to see if I could ask a second time. Is there a list member with a functioning paper tape unit that would be willing to run some examples for this gentleman? At the time I suggested as classroom examples two each of the following: short roll of blank tape punched tape containing a relatively short program hardcopy printout of the program listing (keeping it period consistent, greenbar would be nice) Any volunteers? - here's a chance to help out. He's located in GA and willing to reimburse any costs involved. Steve Shumaker

14 years, 11 months

Help with Power Supply Input Current?

by jhfinedp3k＠compsys.to

I have seen the specs for input current for various power supplies. Obviously, the higher the maximum output current, the higher the rated input current. I would like to buy a power supply that is about double the usual capacity that I will need, but I am wondering how this choice might affect the UPS up time when the street power fails? If the load for two power supplies is the same, will the input current be similar if the maximum output rating of one power supply is double the other power supply, assuming that the load is within the rating of the smaller power supply? Sincerely yours, Jerome Fine

14 years, 11 months

gsaauctions: interesting looking calculator (Winchester, KY)

by legalize＠xmission.com

<http://gsaauctions.gov/lotimages/regn4/41QSCI09471004C.JPG> Dunno what kind of calculator that is, but it looks 'vintage'. Lot 41QSCI09471004 -- "The Direct3D Graphics Pipeline" -- DirectX 9 draft available for download <http://www.xmission.com/~legalize/book/download/index.html> Legalize Adulthood! <http://blogs.xmission.com/legalize/>

14 years, 11 months

486 case LED display jumpers

by ian_primus＠yahoo.com

--- On Wed, 5/27/09, Philip Pemberton <classiccmp at philpem.me.uk> wrote: > You could probably reverse-engineer one with a multimeter > in about 25 minutes. Remove all the jumpers, Set TURBO off, > find all the lines that are high, repeat with TURBO on. From > that you'll be able to figure out which pins are > always-high, and which depend on the state of the TURBO > input. Anything that stays low is a segment. If dealing with > a common-anode display, reverse "high" and "low". Man, I remember setting these up... but it's been a while. When they were new, of course, the cases came with little diagrams and instructions... You should be able to figure it out with trial and error, it's really unlikely something could blow up. Just fiddle with jumpers until you get it to say either the speed of the computer, or "HI". Every one I've ever seen was set up like Philip described, where each of the seven segments could be on normally, on with turbo, or on all the time. Once you figure a couple of segments out the rest should be simple. -Ian

14 years, 11 months

BM 029 Keypunch has arrived

by roger.holmes＠microspot.co.uk

> Date: Tue, 26 May 2009 13:28:12 -0700 > From: "Ed Thelen" <ed at ed-thelen.org> > > Congratulations on your purchase of your new IBM 026 keypunch ;-)) Thanks, though it isn't an 026 its an 029, the one with the squared off case. I happen to have a jelly mould one, though it is an 836 with all the extra bells and whistles like a programming patch panel in the left side pedestal. Trouble is it does not work and it has about 3 times the number of relays as a standard 026 and I can't get circuit diagrams for it. I found someone who could supply them for 100 dollars but he wanted a cheque from a US clearing bank which of course I can't do, and things went quiet when I asked about alternatives. > > Our IBM 1401 restoration operation has 4 IBM 026 keypunches restored > to full operation Aha! I am half of the ICT 1301 restoration project. About the same age, the 1301 was announced 1959 and first shipped in 1962. The project was started by BTM, the British Tabulating Machine company which had just stupidly given up the rights to all IBM's patents throughout the British Empire, which by then was shrinking fast. I saw a picture of three of your guys standing around an online card punch and I planned to send you a picture of the two of us standing around our almost identical online card punch, though I'm sure the electronics underneath are different. The relays and the two banks of bakerlite cams are probably the same. Our has a ancient design of board with a Z80? valve on it which powers down the motor if the machine has not been used for a while. What oil do you use in your Geneva gear box? > > > Several notes: > a) None of ours have a ferroresonant regulator. > They are all as wired in > http://www.ed-thelen.org/1401Project/026-KeypunchSchematic.pdf > general area > http://www.ed-thelen.org/1401Project/1401RestorationPage.html#Unit-Record-E… I know it is slightly too modern for my 1301 but my new acquisition is an 029 model C and there was an IBM Field Engineering manual in it. It is not the more modern one with reed relays, it still has the IBM wire relays used in the 026/836. Looking at the manual again it just says model 29, but I always though they were called 029. Maybe I've got it wrong, or maybe they were only called 029 in the UK. > > > b) One or more of the electrolytic capacitors may need re-forming > A symptom of the need is the immediate blowing of fuses when > powering up. > My favorite method is to place a 4 watt 115 volt tungsten bulb in > series > with the charging circuit to the capacitor. This reduces current > and > local heating in the capacitor to acceptable values while the > electro-chemistry is taking place. > http://ed-thelen.org/1401Project/Sched2005Jan.html > see Wednesday January 19th A four watt 115v bulb! Sourcing one of those locally might be tricky. The machine was powered up in the states before shipment so I might be lucky with this. > > > c) Fortunately, 25L6 tubes are available on e-bay ;-)) Er, no valves in either the 29/029 or the 836. There were some in the verifier. > > > d) Two of the keypunches had an open hold coil in one of the relays. > We couldn't find: > - a replacement > - a volunteer to rewind to solenoid > so did a work-around including a 7 watt lamp as a current limiter. > http://ed-thelen.org/1401Project/Sched2006December.html#13 OK, I might have a spare from the verifier. > > > > e) Strong suggestion: Unless you absolutely have to, > don't mess with the print section. > Getting it lined up again will drive you nutz. > One of ours had run out of lubrication and > the print wires would not move correctly - > Bob Erickson, who fixes analog watches for fun, had a long > "interesting" battle !! Absolutely. Back in 1979 I made that mistake on the 836, I tried to clean the print head with a rag pulled side to side - I bent all the print wires and it never printed again, part of my reasons to buy the 29/029. Not that I've given up totally on the 836 but it is WAY down the priority list. Highest priority is to get the check read brushes on the online punch working 100% so I can use it to (slowly) read the precious old cards I have without wrecking them so badly they can't be manually read and re-punched on a keypunch. > > > f) We "re-ink" our own ribbons - by re-oiling them, as there still > seems to be enough "black" in 'em. Very interesting. > > > g) We have two people who have done most of the restoration on the > four keypunches - > Bob Erickson > http://ed-thelen.org/1401Project/TeamBios.html#Erickson > Joe Preston > http://ed-thelen.org/1401Project/TeamBios.html#Preston > They fixed 'em when they were working for IBM, > Oh so many years ago :-)) > Please regard us a resourse of knowledge if you need help. Thank you very very much. > > > ... > >> >> Looking through the parts list there is something I'd like the list's >> opinion on. The diagram shows a transformer but the list says >> "REGULATOR ASM, FERRORESONANT-60CPS 120VA" and a similar option for >> 50Hz which of course I don't have. What are these for? Might they >> work >> at the wrong frequency? Will they be damaged or just not work? This >> is >> part of a 48v DC supply. Should I build a simple 48V supply myself or >> even see what I can find in my verifier spares? > > The ferroresonant question has been correctly answered in another e- > mail, > Our IBM 1401s are "full of 'em" ;-)) > I did some experiments on one, > they are surprisingly "stiff", ie good. > Ours are rated at 133 volts nominal output > Into a light load, the output stayed within 5% > with inputs ranging from 85 volts to 220 volts :-)) Impressive! Not a transistor in sight either. > According to "Solar" documentation - > the output voltage will vary 1% for each 1% deviation of > input frequency. Hmm, so 10 Hz off of 60 means 10/60 so 16.667% x 48v = 8v so output will be 40v instead of 48. For relay logic that doesn't sound too bad to me but then I've never designed relay logic (except for model railways when I was a boy). > > > Good Fortune > Ed Thelen Thanks and good luck with the 1401 restoration.

14 years, 11 months

Doorbell switch with an intrersting brand name...

by ard＠p850ug1.demon.co.uk

Today I was in one of the fairly local 'pound shops' (for those across the Pond, they're much the same as your 'dollar stores' -- they're shops that sell everything for \pounds 1.00 per item). Anyway, one of the items they were selling was a fairly nice brass doorbell pushbutton switch. No, I have not decided to post somethign totally off-topic to this list. The reason I mention it is that the brand name on said switch is 'Heath/Zenith', and the way they're written is very similar (I'd say identical) to the old Heath/Zenith brand used on classic computers On the pack (amongst other things) are the statements 'Should you require it, Heath Senith offer a range of otther accessories and bell wire' (in that one , the 'Heath Zenith' is in a normal font. And 'DESA UK LTD www.desaeurope.com ... A division of Desa International Inc. The world's largest doorchime company' So is that what happened to the Heath and Zenith brand names :-( -tony

14 years, 11 months

receptacles (was IBM 029 Keypunch has arrived)

by tiggerlasv＠aim.com

As Tony suggested earlier, maybe a cord-mount receptacle might be the easiest route to go. Here is a (random) e-bay 20-Amp cord-mounted receptacle, which takes varying sizes of "SO" (rubberized) cord. . . http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&item=170201407022 Someone had pointed out earlier that, if you're going to use a box-mounted receptacle, that cutting out for a decora style outlet would be the easiest, but I tend to disagree. If you're only going to be plugging in ONE device, then use an outlet like this. . . (Also a random e-bay item) http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&item=260376549688 It's much easier to cut out a single round hole. ;-)

14 years, 11 months

The Museum of Computing gets a new home

by info＠museum-of-computing.org.uk

After a year in storage, the Museum of Computing is delighted to announce that it will be re-opening in July 2009 in Swindon town centre. Our volunteers are now hard at work transforming what was previously retail units into one of the most exciting and original venues in Swindon. The museum will be located at 6-7 Theatre Square, an section of the town that has been designated a cultural area in Swindons regeneration plan. For more information and to see the press release http://www.sourcewire.com/releases/rel_display.php?relid=47892 We would like to thanks all our friends for their support and look forward to welcoming you to the new museum. If you would like to help in any way with the new museum we would be delighted to hear from you. Simon Webb www.museum-of-computing.org.uk <http://www.museum-of-computing.org.uk/>

14 years, 11 months

IEZ-11 driver source?

by kahrs＠caip.rutgers.edu

The IEZ-11 is a VMS driver for the SCSI 488/D box made by Iotech. I have several of these and was wondering if anyone had the source for this driver so I could use it with *ix instead. Also, there is a 488/S box that is apparently compatible with Suns. But that ain't classique.

14 years, 11 months

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test-drb May 2009