Discussion about the Korg PolySix synthesizer

This could be a number of things.  Start with the cheapest first: test 
the rectifiers in-circuit with the power off using the diode checker 
function of a typical DVM.  Check the big electrolytic caps for dead 
shorts..in fact, just replace them.  With the fuses removed, turn on the 
power and measure the AC voltage that appears across the two lower clips 
of the fuse holders.  IIRC it should be around 30VAC.  Unbolt the board 
from the back fo the case and make sure there is no crud underneath 
causing shorts.  Q6 looks a little odd, is the lower lead actually exposed 
going up the side of the part?

  Just a few offhand guesses to get you started...

Crow
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On Sat, 14 May 2005, hoggy_bogger wrote:

> > I'd check the Powersupply board for shorts - I can't remember but I 
> > think there should be a few transistors at the area - check them out 
> > for shorts.
> 
> I disconnected all the power to the other boards, and just had power
> to the KLM-376, powered on and it blew the fuses (both 250v 1a on the
> board).   Obviously there is a short somewhere in that board?  The D1
> diode lights up for a sec when it's powered on, then  dims out.  
> 
> Can't seem to find any shorts in there, any idears?  I have a few
> photos here of the board, maybe there's something obvious to you guys
> (other than the fuses not being in there, took em out)