Vintage Synth Repair

I was recapping the power supply in my E-II and mistakenly fiddled with all four trimpots on the PS circuit, trying to set the correct voltages. I found that only two of them affect the voltage rails (-15v/+15v/+13.2v) but the other two don't affect the voltage at all.

I now have no idea how these other two trimpots (marked as R109 and R110 on the schematics) should be set and am afraid that being set wrongly I will damage the E-II.

Does any of you have any idea what they do and how they should be set, or have an access to the calibration procedure of the E-II ?

here are the two trimpots as appearing on the schematics:
http://www.fileden.com/files/2006/10/13/285304/E-II%20PS.JPG

Thanks very much !!

--- In vintagesynthrepair@yahoogroups.com, "Gil" <gilwe@...> wrote:
>
> 
> I was recapping the power supply in my E-II and mistakenly fiddled with all four trimpots on the PS circuit, trying to set the correct voltages. I found that only two of them affect the voltage rails (-15v/+15v/+13.2v) but the other two don't affect the voltage at all.
> 
> I now have no idea how these other two trimpots (marked as R109 and R110 on the schematics) should be set and am afraid that being set wrongly I will damage the E-II.
> 
> Does any of you have any idea what they do and how they should be set, or have an access to the calibration procedure of the E-II ?
> 
> here are the two trimpots as appearing on the schematics:
> http://www.fileden.com/files/2006/10/13/285304/E-II%20PS.JPG
> 
> Thanks very much !!

Those pots are on the High-voltage DC side of the power supply
These will more likely affect switching frequency of the supply and not any output level
The +12 and -15 will be fixed voltages.
>

Thanks, what does this mean practically ?
I currently set them both to center position, and the sampler works fine. I just haven't managed to find any calibration instruction for the power supply unit. Can you think of any way to calibrate it ? or is it safe to use it this way ? (trimpots to center)

Thanks!


--- In vintagesynthrepair@yahoogroups.com, "Scott" <painintheamp@...> wrote:

>
> 
> --- In vintagesynthrepair@yahoogroups.com, "Gil" <gilwe@> wrote:
> >
> > 
> > I was recapping the power supply in my E-II and mistakenly fiddled with all four trimpots on the PS circuit, trying to set the correct voltages. I found that only two of them affect the voltage rails (-15v/+15v/+13.2v) but the other two don't affect the voltage at all.
> > 
> > I now have no idea how these other two trimpots (marked as R109 and R110 on the schematics) should be set and am afraid that being set wrongly I will damage the E-II.
> > 
> > Does any of you have any idea what they do and how they should be set, or have an access to the calibration procedure of the E-II ?
> > 
> > here are the two trimpots as appearing on the schematics:
> > http://www.fileden.com/files/2006/10/13/285304/E-II%20PS.JPG
> > 
> > Thanks very much !!
> 
> Those pots are on the High-voltage DC side of the power supply
> These will more likely affect switching frequency of the supply and not any output level
> The +12 and -15 will be fixed voltages.
> >
>