On 26.02.20 20:43, Al Kossow via cctalk wrote: Would have loved to pick that up....

I hope I can get this one running.

Bob, I had my 4054A display stop erasing when you press PAGE key or BASIC PAGE command. I found the 4054 Parts and Schematics Service Manual on bitsavers.org at http://www.bitsavers.org/pdf/tektronix/405x/4052_4054/070-2839-00_4054_Serv… I've narrowed my issue using that manual to a 74123 one-shot multivibrator that creates a short delay for the erase to complete. I've got a 74123 IC ordered and should get it this week. When I upgraded my 4054 to 4054A with an F39 option kit - the MAS board and the IO Board were both upgraded. Those schematics aren't in the 4054 service manual. Then I remembered my list of your documents at Living Computer Museum - and there was an 4054A Update to the 4054 Parts and Schematics. I've asked the Museum to scan the manual update and I'll post the scan - so it can be saved on bitsavers.org too. BTW - I plan to exhibit my 4054A with the 4907 floppy drive system at VCF Pacific Northwest Festival at Living Computers Museum on March 21 and 22. Monty On Wed, Feb 26, 2020 at 5:38 PM Mark Linimon via cctalk < cctalk at classiccmp.org> wrote: