We replaced resistor R77 (double check that, I don't have the synth open in front of me. It's above the scale blue trim pot), which seems to control the range of the scaling on osc 2, with a 4.7k.
Works perfectly (so far).
Jim
At 10:57 AM 2/20/2013, you wrote:
Hmm...
My Source is in the shop for a calibration and battery change and there were some keyboard scaling issues as I recall. Good luck with the fix. Any signs of battery acid damage?
Paul T
From: Jim Blair
To: vintagesynthrepair@yahoogroups.com
Sent: Wednesday, February 20, 2013 10:44 AM
Subject: Re: [vintagesynthrepair] Re: Moog Source calibration.
Thanks for the replies.
It's not really a "tuning" issue, it's the stretching of the pitch across the keyboard. When the low note are in tune, the high notes are flat, and I'm at the limits of the range of the Scale and High End Compensation trim pots.
Jim
At 09:01 AM 2/20/2013, you wrote:
Jim,
I'm not familiar with the Source... but could you not bring the overall pitch of Osc 1 down a slightly..? Then retune Osc 2 to it?
Just an idea...
Cheers,
TOM
--- In mailto:vintagesynthrepair%40yahoogroups.com, Jim Blair wrote:
>
> Blah.
>
> Actually, two hours of blah.
>
> Following the service manual, but no success.
>
> Anyone have some tips and tricks? It's all about tuning oscillator 2.
> It's just not stretching sharp enough up the keyboard.
> The front panel Osc 2 calibration doesn't really help much.
> Internally, in order to even get close, I have to have Scaling and
> High End Compensation all the way to the left, but the upper end of
> the keyboard is still flat. No room left to stretch the pitch out more.
>
> Osc 1 is fine.
>
>
>
> Blah.
>
>
>
> Jim
>