IIgs --- no composite video; RGB is okay

[buggie@ben15.unm.edu (stephen e buggie)]

   IIGS CPU:  COMPOSITE VIDEO IS OUT, YET RGB VIDEO IS PERFECT
   ===========================================================

I got yet another IIgs CPU, which passes the self-test.  But the RCA-jack
for composite video output does not work.   The standard db-15 RGB video
output works perfectly.

I removed and inspected the motherboard, but there is no looseness or
physical damage around the RCA composite video output jack.   Physically,
there is no apparent damage elsewhere on the IIgs motherboard.

Any advice on troubleshooting?  I realize that its much better to have RGB
capability than just composite video, but I'd like to repair this fault.
I have several blown IIgs motherboards in the shop from which I could
salvage components ---- I can desolder them okay.

Steve Buggie



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