test-drb May 2012

test-drb@ccmp.vtda.org

189 participants
220 discussions

Free (for the price of shipping) RA-81 chassis

by alanp＠snowmoose.com

I have a RA-81 that I am getting rid of. It is complete except for the disks and the housing that they spin in. It has the motor, so it is still heavy. Probably a local pickup, but I will consider shipping. If there are no takers, maybe it will just appear on the Living Computer Museum's doorsteps. Wait, Ian and Rich subscribe to this list ... alan

14 years

Commodore PET 2001 Video Problem

by wheagy＠gmail.com

Success! I thought I had done the whole reseating of the chips in the socket thing, but messing more with the VRAMs as per your suggestion, seems to have soveld the problem. I tried swapping them and that just made things worse, so I swapped them back and it worked great. Looks like some oxidation in the sockets/pics. So I removed the PETvet and replaced the 6502 and for now, it is running well. Now to test the rest of the machine. Thanks for the help. http://imgur.com/qclhF Win Date: Sat, 19 May 2012 21:35:17 -0400 From: Ethan Dicks <ethan.dicks at gmail.com> To: "General Discussion: On-Topic and Off-Topic Posts" <cctalk at classiccmp.org> Subject: Re: Commodore PET 2001 Video Problem Message-ID: <CAALmim=SKRsX+YVADoEVrn3BNQ_VJd2MSuT==jK6GAbotaJfqg at mail.gmail.com> Content-Type: text/plain; charset=ISO-8859-1 On Sat, May 19, 2012 at 9:23 PM, Win Heagy <wheagy at gmail.com> wrote: > I've made a bit of progress on this since the last post and wanted to get > some additional help if possible. ?I picked up a PETvet board from > bitfixer.org and installed it. ?The 2001 boots now (usually) and I get a > screen like this.... > http://imgur.com/fQxH3 You are quite close now. > The machine works like this, but obviously the vertical lines are a bit > annoying. ?The PETvet replaces the RAM and ROM, but does anyone know if > that includes replacing the video ROM? ?Any next steps are appreciated. Your video (character generator) ROM is likely just fine. It's more probable that you have a either a bad video SRAM or perhaps a stuck bit on the shift register that takes the byte from the ROM. What does the screen look like if you remove the ROM? Do you still see the lines? What if you swap the RAM chips. Does the vertical line move? Since you pulled your RAM for the PETvet, you should have spares to try in the video RAM spot. I've seen up to 25% bad SRAMs in old PETs, so it's a place to focus your efforts. If you can borrow or have a spare character generator ROM, it's worth swapping that out, too. I think you've got it narrowed down to one of 4 chips... ROM, RAM, or shift register. The most likely candidate is RAM, in my experience. -ethan

14 years

cctalk Digest, Vol 105, Issue 45

by elson＠pico-systems.com

From: jim s <jws at jwsss.com> To: General Discussion: On-Topic and Off-Topic Posts <cctalk at classiccmp.org> Subject: Question about Military terminal Message-ID: <4FB8ACE0.8070401 at jwsss.com> Content-Type: text/plain; charset=ISO-8859-1; format=flowed My uncle served in the Navy in the Philippine Islands in a Signal Corps unit doing communications of some sort. One of the interesting souvenirs he made and brought back was a 5 level punched tape, which his oldest daughter had in her collection. This would be Baudot code, used on a bunch of Teletype and Kleinschmidt units from the 1940's through the 1970's, at least. The code is well-known and documented. The Teletype models were such things as the Model 15 and 19, which looked like something like Smith Corona typewriters. There were a variety of sub-models in these families, such as manual-only units (keyboard and typewriter) and ASR (with tape reader and punch). There were also standalone tape readers and punches, and chadless punches, which left a loose flap of the tape where a hole was needed. This same code was still alive in 1991, I found the French-speaking islands like Martinique, Barbados, Guadaloupe, etc. They used a computer to pack the Baudot into blocks and sent it via radio in a synchronous format, but the basic code was still Baudot. Teletypes and Kleinshcmidt machines were used fairly widely during WW-II and even more widely in later wars for transmitting printed orders to the field. Later they were used for transmitting everything like supplies orders and all sorts of routine messages. There were ciphering units for secure messages. If you look at pictures >from the Minuteman silos, you will see a Kleinschmidt printer connected to an AN/UYK-7 computer used to partially decrypt launch orders to the missile crews. Those partially decrypted messages would instruct the crews to each open specified envelopes, and codes in those envelopes could be combined with codes decrypted from data stored in the AN/UYK-7 to create a launch code for the missile. As far as I know, radio hams still use teletypes or software simulations of them to communicate. Packet radio has replaced much of that, however. Jon

14 years

Commodore PET 2001 Video Problem

by dm561＠torfree.net

Original Message: Date: Sat, 19 May 2012 21:23:38 -0400 From: Win Heagy <wheagy at gmail.com> > I've made a bit of progress on this since the last post and wanted to get > some additional help if possible. I picked up a PETvet board from > bitfixer.org and installed it. The 2001 boots now (usually) and I get a > screen like this.... http://imgur.com/fQxH3 > The machine works like this, but obviously the vertical lines are a bit > annoying. The PETvet replaces the RAM and ROM, but does anyone know if > that includes replacing the video ROM? Any next steps are appreciated. > Thanks, > Win ------------------ No, the PETvet does not replace the chracter generator or the video RAM. This one's easy: Your problem is a bad CG or shift register; you don't say which model this is, so, assuming one of the models using a 6540 ROM: - Check that pin 24 of the IC at A2 is not broken or bent. - If it's OK then either carefully bend out pin 24 or, preferably, remove or bend out pin 24 of an IC socket and sandwich it between the chip and its socket. - The screen will probably look the same. - Using a pin and a jumper, ground pin 24 of the socket (not the bent out IC pin); if the screen stays the same it's the SR, if the lines disappear it's the ROM. - If it's an old model using 2316s then it's pin 11 instead of 24. - If it's a dynamic RAM model using a 2316 then it's pin 11 of IC F10. If you need a replacement for the ROM, ask on the Vintage Computer Forum; someone will be able to fix you up. mike

14 years

Platinum Apple //e broken keys

by list_cctalk＠greencroft.co.uk

Recently resurrected my //e from storage (used an ATX PSU as the Apple one let the magic smoke out), and it's got broken keys 0 and . (and missing keycaps) on the numeric keypad. Anyone know a good place to get some replacements in the UK? thanks greg

14 years

Wang Disk Packs - including TM-VS-C

by lbickley＠bickleywest.com

I was doing my usual rummaging around Weirdstuff (WS), when a car drove up and dropped off six (6) Wang 80 MB Disk Cartridges. The P/N on the Cartridges is 725-0183. One of the packs contains the operating system "Task Monitor, TM-VS-C, Release 2.20". The other packs contain system backups. The WS folks alerted me fast enough that I was able run outside and talk to the guy who dropped off the cartridges. Unfortunately, the Wang system they came from was long ago scrapped - including the disk drives for the cartridges. If anyone has a drive which can read the packs and can preserve the OS, etc., please let me know and I'll work with WS to make the packs available to you. Cheers, Lyle -- Lyle Bickley, AF6WS Bickley Consulting West Inc. http://bickleywest.com "Black holes are where God is dividing by zero"

14 years

Commodore PET 2001 Video Problem

by wheagy＠gmail.com

I've made a bit of progress on this since the last post and wanted to get some additional help if possible. I picked up a PETvet board from bitfixer.org and installed it. The 2001 boots now (usually) and I get a screen like this.... http://imgur.com/fQxH3 The machine works like this, but obviously the vertical lines are a bit annoying. The PETvet replaces the RAM and ROM, but does anyone know if that includes replacing the video ROM? Any next steps are appreciated. Thanks, Win On Mon, Apr 16, 2012 at 2:07 PM, MikeS <dm561 at torfree.net> wrote: > ----- Original Message: > Date: Mon, 16 Apr 2012 09:55:12 -0400 > From: Ethan Dicks <ethan.dicks at gmail.com> > > >> Try powering up with the video RAMs removed (they are in the back and look >> like they have dots on them). ?With no RAM, the PET should power up to a >> blank screen > > Tsk, tsk, Ethan, you know better than that ;-) Yeah... thinking about it - that's what you get with the Character ROM removed... sorry. The thing I was trying to communicate was that the video should certainly be uniform with the RAM removed. I just misremembered what "empty" does. > A PET with a working video section and video RAM removed will show the > classic checkerboard pattern or under certain circumstances a pattern of > small black squares. Right... the character for 0xFF is the 50% checkerboard - it would look largely the same in inverse video (unless you count from the edge which "phase" it is). > No doubt there's considerable PET knowledge on this list, but as Terry > suggested previously the VCF forum or one of the PET/CBM-specific lists > might be a better place to find help with a sick PET... Perhaps. I'm not a big forum denizen (too many disconnected places to keep up with) so I rarely see help requests posted to them. -ethan

14 years

VCF East question

by auringer＠tds.net

Hi All, I was wondering about the attendance at the recent VCF. Does anyone have some idea how many people showed up that weren't already active in classic computing? Do you think that we pulled any new people into the hobby? -Jon

14 years

KIM-1 and Commodore [was RE: You're too late now, but

by dm561＠torfree.net

----------Original message: Date: Fri, 18 May 2012 12:04:03 -0700 (PDT) From: Cameron Kaiser <spectre at floodgap.com> > ...But the KIM-1 is much more capable than it appears (this is not saying > much, mind you, but there were numerous reasonably practical applications > for it in the era). If you hooked it up to a terminal, it became much more > useful. Even more so in the case of the AIM 65: with an 80x24 terminal connected to its RS-232 (or current loop) interface and the optional 40kB RAM and BASIC, Forth, PL/65 and Pascal in ROM, it was more powerful (and also better supported) than a lot of its better-known contemporaries, not to mention its on-board printer, 20 (or 40) column display and full keyboard for standalone use. > I liked the AIM-65, personally, but I don't have one. Time you got one then ;-) m

14 years

Any interest in 1990s Microsoft software (MS-DOS, Word, Fortran)?

by kevin_anderson_dbq＠yahoo.com

Back in 1985, while I was still in graduate school working on my doctorate degree, I purchased my first computer, a brand-new Zenith Z150 PC clone. that I actively used into the early 1990s. I still have that computer, although it doesn't run any longer, along with a Zenith-branded composite monochrome monitor that was sold at the time, both in their original boxes. Potentially more important is that I still have all the various levels of software I had bought, including updates, with manuals and original diskettes. I haven't done a complete inventory, but there should be several versions of MS-DOS up to I believe version 5, Microsoft DOS-based Word (from I believe version 1 up to 4), Microsoft FORTRAN (probably two versions), and maybe some miscellaneous stuff like Turbo Pascal. I would also have a complete set of Bitstream fonts. Again, all of this should have matching manuals and original 5-1/4-inch diskettes. Most of this is branded as Zenith, but isn't necessarily limited to just the Z150 computer. Is there anyone interested in the lot somewhere close to Dubuque, Iowa? If so, please get in touch with me and we can talk about a price. I am getting ready to sell the house and would really rather not throw this lot into the rubbish bin or give the computer to the local scrapper. It's got to be more useful to someone else. Let me know. Kevin Anderson Dubuque, Iowa

14 years

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test-drb May 2012