Vintage Synth Repair

I have had a polysix that I've been wanting to restore or at least repair to a working state again. The power wire has been replaced and I'm not sure its correctly connected, so I guess I'll start there! When I plug the synth in it just hums constantly unless I switch the tape output switch then the hum gets softer. All the lights are on and I'm not sure if this is correct or if a power problem is causing this. The speed knob seems to be working but nothing else as far as sound or knobs. Anybody have any ideas where to start? 

Thanks, TheCat

Does it have the infamous battery damage?

A blinking speed LED indicates that the key assigner circuit is probably
working (which also means that the four key mode buttons should
theoretically work).

If all the other lights in the programmer section are lit it hints at a
problem with the processor board (KLM367).

There is an active Polysix yahoo group which I suggest subscribing to.

I would start in usual way - with power supply, cleaning all  
connectors, reseating IC's in sockets if there are any, changing RAM  
battery, then...

I sold all my PS6 I had in the past, so I forgot about it. But for  
sure not all LED's should be lit.

If you don't have Service Manual, I'm sure it can be easily found on  
the net. Or I can send it to you. There were two different production  
versions of Polysix.

Daniel Forro

On Nov 6, 2011, at 12:31 PM, ericthecat@... wrote:

>
>
> I have had a polysix that I've been wanting to restore or at least  
> repair to a working state again. The power wire has been replaced  
> and I'm not sure its correctly connected, so I guess I'll start  
> there! When I plug the synth in it just hums constantly unless I  
> switch the tape output switch then the hum gets softer. All the  
> lights are on and I'm not sure if this is correct or if a power  
> problem is causing this. The speed knob seems to be working but  
> nothing else as far as sound or knobs. Anybody have any ideas where  
> to start?
> Thanks, TheCat