Vintage Synth Repair

Thanks, I'm supposed to get it in, in a few days, so I assume I will have a better idea what's going in there... That particular one if told to be the first version of the Minimoog D. I don't think it has been played much as the pratt-read keys are totally in one level and the bushes are not sticky as you would expect from that old keyboard. One the other hand it looks as it has suffered some abuse, might be only thrown at storage for years... Testing for voltage stability will surely tell something about the problem being supply related or a contact issue as Tom suggested - although I can't see how a drift could be observed without seeing a drop in voltage - it IS supposed to be voltage controlled after all :/ 



--- In vintagesynthrepair@yahoogroups.com, "Quazimodo" <noddyspuncture@...> wrote:
>
> On my Mini these crimped connectors DID affect all oscillators equally! In fact, the tuning drifted - but also the SPAN (Scale?) drifted, again equally for all Oscillators. So not only was the synth out-of-tune... but also out-of-tune with itself over the octaves... if you get my meaning. The higher end went "sharper" etc.
> 
> Easy way to check... take the back off and just move those wires slightly with a pencil... see if the symptoms come and go.
> 
> Cheers,
> TOM
> 
> 
> 
> --- In vintagesynthrepair@yahoogroups.com, Malte Rogacki <gacki@> wrote:
> >
> > No, no, no:
> > 
> > You're not supposed to solder the connector to the PCB, just the wires to
> > the connectors! The stock ones are only crimped.
> > 
> > But before you jump to this let's examine the problem a bit deeper. Since
> > all three oscillators are affected it is very likely that the source sits
> > somewhere before the summing amp of each oscillator. I'd try to see if one
> > of the various control voltages suddenly changes. Same for the supply
> > voltages.
> > The common control voltages are
> > 
> > - Bend
> > - Tune
> > - Keyboard
> > - Mod
> > - Ext
> > 
> > if I'm not mistaken.
> >
>