Got a 128!

Picked it up on a whim, for dirt cheap.  Came as-is, untested.  With a 1541, an Atari 2600 Jr. (why, I don’t know, but whatever, I love the 2600).  1541 needs to be cleaned with holy water, as it’s acting a little odd.  I already have 8 or 9 of them, so it’s not that important to fix right now.

Needless to say, it works!

It has some problems.  Missing a key, a spring, and the plungers are broken.  I managed to fix the tab key (needed a spring) so that it didn’t constantly tab the cursor when the machine was on.  The missing key (ALT) is long gone, and I was told these keys are as rare as hen’s teeth.  So It’ll probably be missing for a really long time.

Last problem (so far) and the biggest:  They keyboard matrix was acting weird.  I tore the keyboard apart checking continuity, swapped the 6526 chips around to rule those out.  After more tracing, I found this:

Good times.  The faint blue circle is the problem child.  It’s not allowing EMI21 to connect with pin 3 of the CIA.  Someone recommended a silver conductive pen to fix, but they’re $70 and don’t last.  Another was a fiberglass pen to scrap it down to the copper and solder a jumper wire in there.  I’m going my own route, and soldering a jumper on the underside of the board.  That way I can’t hurt anything (like the socket).