Archive of the former Yahoo!Groups mailing list: Discussion about the Korg PolySix synthesizer

Hello PS6ers. Just got one of these babys which looks great with my
Sigma. I bought this thing knowing it didn't work hoping it was a
battery problem but I found out the the rectifier diodes on the power
supply were shot. After replacing them and all of the lytics,I got
LEDs to light up and +5v and +15v were present but no -15v and -5v.
After further investgation, I found that by unplugging the boards
both negative voltages appeared. My thought was "dead short on one of
the boards". I did a primitive "put the ohm meter across each plug
contact to ground" to see if a dead short would stare me a the face
but that wasn't the case. I then loaded a few different resistors
across the power supply -15v terminals with all of the boards
unplugged to find out that if can reproduce the problem. The voltage
was stable until I went down to 100 ohms and then I noticed the
voltage drop immediately. I then put the 100ohm resistor across the +
voltages to see if I could get those voltages to drop but they stayed
stable. My first thought was that one of the regulators/transistors
is weak or bad so I was able to find replacements and got them on
order. This is a stab in the dark so I'm asking for some of your
thoughts/advise. Replacing the regulators/transistors/ and the 2 ICs
will not hurt. But I'm not totally convinced that this is the whole
problem. I noticed that some of the power supply circuits have been
changed once before therefore some phenomina is happening or the guy
who had this before had some bad luck with line voltages. Hope to
hear from you experts and thanks to reading this email.