So the workshop was great for all of us! Lots done, lots of fun! :) 16 showed up Saturday, 8 Sunday. 5 of us worked on Commodore 1541 drives Saturday. Others worked on S100, PDP-8, Terminals, etc. The five working on the 1541s mostly sorted through The Federation's 1541 drives and tested which were good, medium or bad. Some were fixable with just using a q-tip and alcohol to the drive head. Some attempts at re-seating chips and voltage testing was done, but only for a small percentage of the drives. Further repair and diagnostic wasn't possible due to running out of time. I worked on my own personal 1541 drives myself was only able to tell which were working or not without opening up, repairing or running diagnostics. I spent a lot of time helping with The Federation drives and other Federation business (running the workshop etc.) and had little time for my own stuff. I did learn from Bill Degnan basic troubleshooting for 1541 drives. I hope to work on them and apply what I learned next month and be able to actually guarantee most of them 100% working. We had a special visit on Sunday from Rob Clarke. He is a Commodore guru who lives in Switzerland. He was in the Philadelphia area for some other event and hung out with us on Sunday. Since I lost all my Commodore help with the 1541 drives (they went home Saturday night), I decided to get Computer Eyes up and running. After about 3 hours I was able to get it to work! I captured a black and white image of myself and later a group photo. I even printed them out. Can others tell what they worked on and their progress? Our next Workshop is Feb. 27/28. I hope to see many of you there!
I worked on my TI Peripheral Expansion Bay and floppy drive. With the generous and expert help of Doug, Ian, Jeff, Jeff, Jeff and others it was checked out, cleaned, running and fixed. On Sunday, January 31, 2016, Jeffrey Brace via vcf-midatlantic < vcf-midatlantic@lists.vintagecomputerfederation.org> wrote:
So the workshop was great for all of us! Lots done, lots of fun! :)
16 showed up Saturday, 8 Sunday. 5 of us worked on Commodore 1541 drives Saturday. Others worked on S100, PDP-8, Terminals, etc. The five working on the 1541s mostly sorted through The Federation's 1541 drives and tested which were good, medium or bad. Some were fixable with just using a q-tip and alcohol to the drive head. Some attempts at re-seating chips and voltage testing was done, but only for a small percentage of the drives. Further repair and diagnostic wasn't possible due to running out of time.
I worked on my own personal 1541 drives myself was only able to tell which were working or not without opening up, repairing or running diagnostics. I spent a lot of time helping with The Federation drives and other Federation business (running the workshop etc.) and had little time for my own stuff. I did learn from Bill Degnan basic troubleshooting for 1541 drives. I hope to work on them and apply what I learned next month and be able to actually guarantee most of them 100% working.
We had a special visit on Sunday from Rob Clarke. He is a Commodore guru who lives in Switzerland. He was in the Philadelphia area for some other event and hung out with us on Sunday. Since I lost all my Commodore help with the 1541 drives (they went home Saturday night), I decided to get Computer Eyes up and running. After about 3 hours I was able to get it to work! I captured a black and white image of myself and later a group photo. I even printed them out.
Can others tell what they worked on and their progress?
Our next Workshop is Feb. 27/28. I hope to see many of you there!
On 1/31/2016 11:53 PM, Dean Notarnicola via vcf-midatlantic wrote:
I worked on my TI Peripheral Expansion Bay and floppy drive. With the generous and expert help of Doug, Ian, Jeff, Jeff, Jeff and others it was checked out, cleaned, running and fixed.
On Sunday, January 31, 2016, Jeffrey Brace via vcf-midatlantic < vcf-midatlantic@lists.vintagecomputerfederation.org> wrote:
So the workshop was great for all of us! Lots done, lots of fun! :)
16 showed up Saturday, 8 Sunday. 5 of us worked on Commodore 1541 drives Saturday. Others worked on S100, PDP-8, Terminals, etc. The five working on the 1541s mostly sorted through The Federation's 1541 drives and tested which were good, medium or bad. Some were fixable with just using a q-tip and alcohol to the drive head. Some attempts at re-seating chips and voltage testing was done, but only for a small percentage of the drives. Further repair and diagnostic wasn't possible due to running out of time.
I worked on my own personal 1541 drives myself was only able to tell which were working or not without opening up, repairing or running diagnostics. I spent a lot of time helping with The Federation drives and other Federation business (running the workshop etc.) and had little time for my own stuff. I did learn from Bill Degnan basic troubleshooting for 1541 drives. I hope to work on them and apply what I learned next month and be able to actually guarantee most of them 100% working.
We had a special visit on Sunday from Rob Clarke. He is a Commodore guru who lives in Switzerland. He was in the Philadelphia area for some other event and hung out with us on Sunday. Since I lost all my Commodore help with the 1541 drives (they went home Saturday night), I decided to get Computer Eyes up and running. After about 3 hours I was able to get it to work! I captured a black and white image of myself and later a group photo. I even printed them out.
Steve Toth and I were the first string 1541 testers. We did a quick clean with a disk format head cleaner and then some functional testing. We tested about half seeing if the drive would load DK Junior from a "reference disk". Turned out many would load the first part of the program, but the "chain" to the next part would hang. We judged that this perhaps was an unfair test not actually knowing the absolute quality of the diskette involved. So we switched to using Chris Fala's 1541 test cartridge which did a r/w performance test. Turns out we had some good documentation to recalibrate and board troubleshoot but we didn't really have time to dig in to that level (which I think we all thought we would). There were a lot of drives to give a first pass to! The usual good time getting together with the workshop crew!
Can others tell what they worked on and their progress?
Our next Workshop is Feb. 27/28. I hope to see many of you there!
On Sun, Jan 31, 2016 at 11:44:48PM -0500, Jeffrey Brace via vcf-midatlantic wrote:
Can others tell what they worked on and their progress?
Worked on the straight 8. I fixed the known fault of accumulator bit going to zero when it was rotated left. This was a bad diode on one of the accumulator boards. I also replaced two bad bulbs and a third that died during the repair. Since one that died was one I previously replaced I'm going to use the not quite matching bulbs with heavier wires for future repairs. The wires are just too thinn on the 1762 bulbs and now that they have aged they break too easy. I then found that the teletype interface wasn't working and replaced a diode on a R220 to fix output. Input is not working properly. I have traced it to a particular flip flop on a R220 where when the data changes it feeds through to the output without the clock active. I ran out of time to identify the component that needs replacing. The teletype is also not working properly. I did not get any time to look at it. I also helped Herb with his 8/A. I will let him describe that activity. Had a good time talking with people and seeing what they were working on.
Huge thanks to everyone who helped check out the group's disk drives and who helped us save warehouse space + increase budget by adopting some of the excess!! A personal thank you to David G. for the PDP-8 operation lesson. I previously understood the very basics of how front-panels tell a computer what to do and how they report the output back to users -- enough to satisfy most museum visitors who ask simply, "How does the [Altair / PDP-8 / etc.] work>" -- but David sat me at the controls and answered all my questions about how to actually enter his chasing-the-lights demo program, verify it, and run. He also showed me the 8's interior "restart" switch, so I can demonstrate core memory keeping its data after the computer is restarted. I'll need some more practice (any recommendations for a web-based or Linux emulator?), but now I feel pretty comfortable that I can teach this same simple lesson to others.
On 1/31/2016 11:44 PM, Jeffrey Brace via vcf-midatlantic wrote:
So the workshop was great for all of us! Lots done, lots of fun!:)
Can others tell what they worked on and their progress?
Our next Workshop is Feb. 27/28. I hope to see many of you there! I was testing and repairing S-100 boards from the stash that I have accumulated over the last 5 years or so. I have been meaning to set some time aside to test some boards and never seemed to be able to get to it so the workshop was a perfect opportunity to concentrate on the task. I tested quite a few boards, a good number worked as intended, fixed a few by replacing and reseating chips and found found a few that need more attention to get working. I also brought a number of both vintage and news blank S-100 boards to build but I never got around to it. Perhaps I will find time at the February workshop as I already have my hotel booked. It was a lot of fun talking to the other participants and seeing what they were working on. Looking forward to the next workshop! Jeff Galinat
I'd like to thank Ian for the lesson on AC DC conversion in a display power supply board. I'd like to learn more about this, but I feel like I finally get the basics enough to troubleshoot these boards. I have always kind of kept to the DC side of things. Bill
participants (7)
-
David Gesswein -
Dean Notarnicola -
Douglas Crawford -
Evan Koblentz -
Jeff Galinat -
Jeffrey Brace -
william degnan