Commodore P500 (aka C128-40) |
Commodore Models - 10 have SID chipsby billdeg Total messages in this thread: 1 The following 10 American Commodore computers models with at least one unit sold in stores and also had SID chips are: The Commodore P500, also known as the C128-40 was the first Commodore model with a SID chip.
P500
C64
SX64
C64C
C128
C128D
B500
CBM 128-80
CBM 256-80
B128
Honorable Mention, but not sold in stores:
C64 LCD
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A donation storyby billdeg Total messages in this thread: 3 Updated: [ Archiving Wafers to WAV ] 07/02/2009 As you may or may not know last year my VCF exhibit was supposed to be on the Exatron Stringy Floppy. A month before the show all my drive's belts snapped, and I had to switch my exhibit to a different subject. And that's why I did the TRS 80 Model 1 30th anniversary exhibit. Not my first choice, but that's the way it goes. hoo haa. Since then I found a company to engineer replacement belts. It took 4 belt size/width attempts to finally get it right. Great, 6 months late but I finally had a working drive. I given the parts and such I accumulated I was able to assemble 3 working drives and I was able to use the belt for another related project that uses the same motor/belt. It pays to stick with things. "A donation story" Around lunchtime Friday I was working down stairs at my office in Wilmington, on the IBM Series 1 friends helped me move around Christmas time. The">... [ read more ] |
Panasonic Senior Partnerby billdeg Total messages in this thread: 1 The Panasonic Senior Partner is an attractive IBM clone portable with a built-in printer. ![]() The Panasonic Senior Partner running DOS 2.1
I built a boot disk to be stored with it, and I guess it was a DOS 2.1 machine but I don't have the manuals and such.
More pictures">... [ read more ]
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The lost NASA tapesby billdeg Total messages in this thread: 1 This is an article that illustrates the importance of preserving the skills needed to preserve ancient data from being lost. From Computerworld online: The lost NASA tapes: Restoring lunar images after 40 years in the vault A Mac Pro and 40-year-old tape drives are helping restore the original Lunar Orbiter tapes http://www.comp...12&pageNumber=1 Here are some pictures from an actual Apollo lander computer, courtesy Frank O'Brien from VCF East 3 2006. Apollo Guidence Modules Apollo Guidence Module Closeup 1 Apollo Guidence Module Closeup 2">... [ read more ] |
Bubble on a 16v 3300 ufby billdeg Total messages in this thread: 3 Updated: [ Altair 8800 power supply capacitors ] 06/30/2009 has been restoring an Altair 8800 S/N 220744K. By participating in the restoration process I have learned a whole lot and I am starting to apply this knowledge to this and other projects. For starters, I am going to test every electrical component and compare with another 8800, same model. I want to try to get them both running by comparing and contrasting how they work. This is a good approach for the amateur, if you can find another working system and you know how to use a voltmeter and soldering iron. Anyway, As I was testing the caps in the back by the power supply I found that one of the caps is about to go: Image of Altair 8800 16V 3300 uf capacitor with a bubble forming on the plus side. It's the o">... [ read more ]
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VTL-2 for Altair 680bby billdeg Total messages in this thread: 3 Updated: [ VTL BASIC for 680b - Working ] 06/25/2009 Just a quick note...I have been working with Grant Stockley to build and test ROMs for VTL-2. I helped test. Grant sent me a copy of the three PROMs needed to load Very Tiny Language 2 (VTL-2). Here is the current status. I put all three PROMs in place. I was not able to boot to BASIC, instead I get various inconsistent results and no "OK" prompt. Sometimes a series of 10 or so " . " characters, scroll down the screen, one per line before the system halts; sometimes just a single letter will appear, sometimes nothing happens at all. There are more details, but that's the long and the short of it. I can't get to the ACIA monitor prompt if all three PROMs are in place. I was able to use the toggle switches to check memory. Working backwards from the end of VTL-2, I found that all of the memory was intact/correct (spot checking a few dozen locations). The program is loading">... [ read more ] |
Analog Computers 1961by billdeg Total messages in this thread: 1 ![]() The cover of Popular Electronics December 1961, featuring analog computers.
NOTE: You will need to log in (or create an account) to download these articles.
In the photo above this General Electric EF-140 uses an audio signal generator to send output indicating a correct answer through a headset. The dials have logarithmic and trigonometric scales, plus squared and reciprocal scales.
Best Buys in ED-EL Kits (includes some educational analog computers) by Louis Garner Jr.
An Introduction Info Analog Computers by Julian Sienkiewicz
Advertisement for Minivac 601 Analog C">... [ read more ]
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Altair 680b (2nd)by billdeg Total messages in this thread: 6 Updated: [ FUA7805 in Q1 on 680 mother bd ] 06/21/2009 Two versions of the Altair 680b. The left unit has the older round toggle switches, the right has the newer flat switches. Click for larger image.
I was lucky enough to get a "new" Altair 680b, very similar to my first one, but with the expansion connector, a 680 cassette card (KSCAR), a 2P/SIO, and two hacked SWTPC MP-M 4K RAM cards attached to a 680 expansion card.
To start, I am checking the IC and voltages. I am able to toggle and recall memory within the first 1K, but the ACIA in ROM slot T is not being written to memory (FF00 --). I swapped the ROM and the ACIA (6850) chip into a working system, to verify that the these chips are OK...they are..so..
I started checking voltages and so far I have found a bad voltage regulator and">... [ read more ]
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Heathkit H-19 Restorationby billdeg Total messages in this thread: 1 Thank you for Herb Johnson who helped troubleshoot and advise repair strategy I bought an H-19 terminal a while back for parts. The previous owner had started converting this computer into a sort of H-89, with power for disk drives and a cassette port. She/He did not get very far. Voltage regulators on the display control board - OK Power supply controller - bad 12-volt regulator (103). Not needed if we're just reverting to a H-19, but might as well fix if ever in the future someone wants to upgrade this to an H-89 with drives. UA78H12S0 Adjusted the yoke to align the display Serial port is marked "330-337", near the brightness knob. Now it works great, using now for testing systems.">... [ read more ] |
Another VC Hacking Weekendby billdeg Total messages in this thread: 1 This time we were put up by Mike Lowen, who hosted the weekend. Pictures: http://sturge...ewen/Oldtech/VCW/ At a minimum,progress was made with the following 2 Heathkit H-89 Computers 1 Heathkit H-19 Terminal 1 Altair 680 - testing VT BASIC 1 Altair 680 - board repair 1 IBM 029 Card Punch Unit - Almost fixed Donner 3500 - Tubes tested and OK Attendees: Herb Johnson, Bill Degnan, Alex Bodnar and Barry Kline, Mike Loewen. Herb Johnson's page from the event: http://www.retro...m/restore/r_loewen.html">... [ read more ] |
Atari 800 ... portable?by billdeg Total messages in this thread: 1 Well not exactly. This unit sports a handsome Casemaker travel bag. ![]() The Atari 800 with a Casemaker travel bag. Click image for larger version.
I don't pay much attention to Atari computers on this web site, but I do think that they're a great company.
I have a small project involving the restoration of the metal shields that are attached to the underside of the cartridge cover. The shields sometimes detach from the inside lid of the cartridge cover because the system's adhesive foam deteriorates.
Three 16K RAM cards and one 10K ROM card are installed in">... [ read more ]
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Cataloging ESF wafer libraryby billdeg Total messages in this thread: 2 Updated: [ format wafer in 2nd stringy drive ] 05/29/2009 I am in the middle of cataloging all of my working ESF programs. I have been side-tracked by other projects, but soon enough I'll get through it all. ...a few screen shots taken during testing: http://www.vin...on_stringy_floppy/ I sold my spare Exatron Stringy Floppy drive on Ebay last week. What's next... Using TRS 80 Model 1 1. Implement a method for converting wafer contents to cassette (Users guide has instructions) 2. Implement a method for converting wafer contents to disk The issue with #2; you can't have the expansion unit and the ESF operating at the same time because they use the same expansion port. So what I believe you have to do is set up two TRS 80's and share one cassette drive. The first TRS 80 will have the stringy floppy and the cassette, the 2nd will share the same cassette (using a switch box) player and wi">... [ read more ] |
Hobbyist Computerized Bulletin Boardby billdeg Total messages in this thread: 1 I have posted a scan of the Nov 1978 Byte Article (page 150) Hobbyist Computerized Bulletin Board by Ward Christensen and Randy Suess This is the important article about the famous CBBS/Chicago BBS - Considered the first home brew BBS. http://vintageco...0ward%20christensen.pdf">... [ read more ] |
Old Timer's Day at PACSby billdeg Total messages in this thread: 2 Updated: [ Slides from Meeting ] 05/17/2009 The Philadelphia Area Computer Society cordially invites the members of MARCH to: "Old Timer's Day" Saturday, May 16th 2009 Super Giant food store Community Center, 2nd Floor 315 York Road Willow Grove, PA 19090 With a special guest appearance by: Bill Degnan from 12 to 1 PM. There will be tables set up for folks to demonstrate their vintage computers after Bill's talk. For further information go to: www.pacsnet.org Please plan to attend, to make this a very special day. Thanks, Ron Kushnier ">... [ read more ] |
Total messages in this thread: 2
Updated: [ CBM P500 PAL to NTSC Conversion ] 07/11/2009
The Commodore P-500 was the first to have a SID chip installed.