Korg Poly800/EX800 Users

Hi, Gordon,

I know that blind crazy replacing of all caps is not good...

But... is it possible that one half of amps in quad op amp LM3900  
work, and another one or two amps are faulty?

That op amp is soldered... that would be uncomfortable to get it out.  
The best way to cut pins and get them one by one. And solder new  
socket...

Daniel Forro


On Jan 15, 2016, at 8:55 PM, Gordonjcp gordon@... [korgpolyex]  
wrote:
>
> I'd look at the opamps first.
>
> In the thick end of 30 years of repairing electronic equipment, I've  
> found maybe about seven or eight genuinely faulty capacitors that  
> weren't in cheap shitty switched-mode power supplies.
>
> Whatever you do, do *not* "re-cap" it.
>
> -- 
> Gordonjcp MM0YEQ