polaris semi-successful surgery
2007-09-19 by spistrich
I finally got some more "orange S+H caps" and went back at my bad #5
and 6 voices with the soldering iron ....and now # 5 works fine..yea!...
But #6 is still distorted and raspy and sounds like 2 out of sync
oscillators in chorus but TUNE ALL wont fix it , it just shuts off
voice #6. I can play #6 alone and it is not like the others.(it always
sounded a little worse than #5 when both were bad) and it doesnt go
away when i hit the sync button. (that made the other bad voice #5
sound better 'temporarily' before i replaced the s+h caps) So i tried
switching the two 4105 chips with another voice and that didnt solve
it. Now i did damage 2 of the board traces around the .33mfd caps on
#6 (it was the first one i did...got better at it) but i carefully
established continuity with solder and a tiny piece of fine wire and it
looks like its ok. Particularly the 3/8" long trace that joins one
leg the 2 smaller .33 caps. cause the short trace ripped out of the
board when i pulled the old cap out. THESE 2 SMALLER CAPS ARE SUPPOSED
TO BE CONNECTED ---RIGHT? [Ive done that sort of pc board trace repair
before on a Korg polysix and it worked ]
So im wondering if THe voice problem might be elsewhere, but where?
another chip? I would like to think that I didnt damage the Caps again
when soldering... and my other big question is WHAT DO I LOOSE IN
PERFORMANCE AND SOUND QUALITY IF I JUST KEEP VOICE #6 TURNED OFF AND
FORGET ABOUT IT FOR NOW?
and 6 voices with the soldering iron ....and now # 5 works fine..yea!...
But #6 is still distorted and raspy and sounds like 2 out of sync
oscillators in chorus but TUNE ALL wont fix it , it just shuts off
voice #6. I can play #6 alone and it is not like the others.(it always
sounded a little worse than #5 when both were bad) and it doesnt go
away when i hit the sync button. (that made the other bad voice #5
sound better 'temporarily' before i replaced the s+h caps) So i tried
switching the two 4105 chips with another voice and that didnt solve
it. Now i did damage 2 of the board traces around the .33mfd caps on
#6 (it was the first one i did...got better at it) but i carefully
established continuity with solder and a tiny piece of fine wire and it
looks like its ok. Particularly the 3/8" long trace that joins one
leg the 2 smaller .33 caps. cause the short trace ripped out of the
board when i pulled the old cap out. THESE 2 SMALLER CAPS ARE SUPPOSED
TO BE CONNECTED ---RIGHT? [Ive done that sort of pc board trace repair
before on a Korg polysix and it worked ]
So im wondering if THe voice problem might be elsewhere, but where?
another chip? I would like to think that I didnt damage the Caps again
when soldering... and my other big question is WHAT DO I LOOSE IN
PERFORMANCE AND SOUND QUALITY IF I JUST KEEP VOICE #6 TURNED OFF AND
FORGET ABOUT IT FOR NOW?