Discussion about the Korg PolySix synthesizer

Both the crystal and capacitors have characteristics quite important to achieving god oscillation, especially in the old days. ;-)  Make sure all the values are spot on and that the crystal is of the correct type/cut. You should be able to use the crystal from the old board using normal desoldering techniques. Hope the old crystal is functional. Also be careful of too much flux or other contaminants in osc area.  

The scope will probably show a weak sine wave only. I don't have a Polysix, so I'm just speaking in general terms here. Where you should see a decent square wave is on the address lines (as low order as you can get without running into the data lines if they are multiplexed on this CPU).

GB