2600 repair suggestions needed

Robot robot at sdic.net
Sun Jan 12 11:46:27 CET 1997

Okay, I just got a scope from a gratious engineering family member who had
it sitting, collecting dust in his garage.  So I thought I'd like to tackle
my bum S+H on my 2600.  I traced though some of the things that might be
going wrong.  The noise generator works fine and makes it to the pin in on
the 4015 module just fine. The internal clock works fine and is correctly
converted to a pulse trigger on the rising edge for the pin in on the 4015.
No output though.  The service docs don't have schematics of the individual
modules as I presume ARP had originally never intended for techs to work on
modules.  They probably believed some module replacement deal would work
under warrantied parts, etc.  But alas now that it is a million years later
and ARP has deceased and I don't know the best plan to aproach it.  The
sevice docs I have simply say replace the module if it's not working.  DUH!
I need to fix it though. So far I have pulled the 4015 out and am planning
to start by replacing the caps as I haven't a very good way of determining
which if any caps are bad.  My DMM does capacitance but it only seems to
work properly when the cap is removed from the PCB.

Any help or suggestions on the best approach to fixing the poor sample&hold
module for my 2600 will be very appreciated.

-robert           | |___   ____   ____ _____
                  | |_  \ / -__/ /  _/ |  _ \     __________
                  |_____/ \___\  |_|   | |__/    / -studio- \
_________________________________      |_|
http://icse1.ucsd.edu/~rcurlee/  \

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