"Robert Bullock" wrote in message
news:YEn3e.59$Iq6.35@okepread01...
I have a Pac with a low 6M* line, when I piggyback a 74LS86 (IIRC,
whatever
chip generates that signal) on it, it's fine, but taking it off, the game
'bogs down', sometimes, but plays with no glitches but somtimes the music
slows down speeds up, etc. Looks like low TTL levels measured at Pin 1 on
the z80 sync buss card. When I say piggyback, I put my logic comparator on
it and it raises the levels by about .4V

Do folks just slap some HC chips in the circuit or is there a better
classic
way to fix this? Course I could just solder a duplicate chip on top I
guess.
I suppose something else tied to that line may be pulling it down but I
haven't gotten that far yet. Replacing the crappy sync buss single wipe
socket may help of course.

Ideas? Does anyone talk fairly serious tech here or should I take all this
to sci.electronics.repair?


You've either got a weak chip driving the bus, or something is pulling it
down. Try replacing the chip driving first and see where that gets you.