On 11/21/09, Philip Lord <email@example.com> wrote: > Hi again, > I just wanted to say a big thanks for everyones help, and to apologize > for being such a dumbass for not being able to fix the board. > > Anyway, Ethan has the boards now, and has kindly offered to take a > look at the problem for me. Thanks again Ethan. So far, it looks like the one board with the PSU issues has fried rectifier diodes - With ~9VAC coming onto the board from the brown wires from the transformer, I get 1.8VDC at the inputs to the 7805s. As for the other board, the one with the 2316 Character ROM on a 6540 adapter that seems to be flaky, I happened to have a 6540-010 ROM and dropped it in place of the ROM adapter. The board comes up, displays the BASIC startup message, and runs a simple loop and print BASIC program. It's hard to read the 2316 Character ROM because of the rust on the package, but it appears to me to read 901447-12. This is interesting because the only ones I was aware of online copies of are -08, -10, and -14 (all of which I think I have in actual boards). -12 could easily be a "lost" Japanese variant. I just need to build a 6540-JEDEC adapter and I can read this out. I don't think I have any 3A rectifier diodes lying about to fix the one board, but they are under $0.20 from most suppliers. -ethan Message was sent through the cbm-hackers mailing listReceived on 2009-11-23 15:00:10
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