Met Dave Kerr at the Hamfest in Brampton. He gave me a number of old chips for the Mod 80 along with a decent 5V power supply. Among the chips were some more 1702A EPROMS and several dozen 2102A RAM chips, including a great many early MIL gold plated chips. Some were made in 1972. Also got a nice MIL MF8008A CPU chip as well. Among the parts I got there was another custom vector board that was made so that the monitor 80 code located in high memory could be executed automatically upon system reset.
Mod-80 Restoration: Got a hold of a RS232 to current loop converter. This allows me to connect the teletype to my PC. I was successful in both transmitting and receiving data from teletype machine at 300 baud. Now all that remains is to figure out why the print head occasionally doesn't line up correctly. Ordered a full manual with schematics for troubleshooting. Hopefully I can solve the issue.
If not, the tests proved that I should be able communicate with the Mod-80 computer through a PC at least. I will, however have to figure out how to get the Mod-80 TTY board to communicate at 300 baud instead of 110 baud.
Replaced all the 22 uF electrolytic capacitors on the boards with new ones. The new ones fit better and of course, the old ones could have been dried out by now.
Also removed all the components from the Mod 8-2 board and restored it to its original design condition.
Noticed that one if the transistors on the board seemed to have a melted lead.
Patched some trace cuts as well.
Charles Baetsen holds a Bachelor and a Master's degree in Engineering Physics from McMaster University in Hamilton, Canada.