23 Jul
2013
23 Jul
'13
10:46 p.m.
________________________________
From: Tony Duell <ard at p850ug1.demon.co.uk>
To: cctalk at classiccmp.org
Sent: Saturday, July 20, 2013 2:03 PM
Subject: Re: HP 9830A always turns on with blank display
Right. My guesss is that it's the Init/ signal from the power supply that
is the root of the problem. Porbbly the I/O flag circuitry on the I/O
interface PCB is not being initialised or soemthing.
Check that 74121 on the PSU board and especially the 6.8uF capacitors
around it.
-tony
I will check this out, hopefully this weekend.? Out of curiosity, is there an extender or
some other way of probing these boards while powered up??
By the way, does anybody know the number of the mating plugs to make a cable for the 9866A
printer?? It looks like a 19-pin cannon connector.? These seem expensive, so at least it
would be nice to be confident I'm seeking the right model.? Any info on plugs and
cable would be welcome.
Many thanks,
Dave?