[sdiy] Fwd: Jupiter 8 pitch bend board issue

[Massimo Gremini]

Hello to every one, I'm trying to repair this beautiful synth (first
version with kenton midi mod) for a friend with no luck since now.
here's the problem.
If you engage the VCO1 or VCO2 switch then pull up the the range fader
pitch start to bend down immediately even if is centre position.
Checked voltage rails +15 and -15 looks good on my DVM.
pitchbend pot is working, ad range fader are ok.
turning trimpots VR1 and VR2 has no effect on pitch range and if I check
them I display a max range of 18kohm (should be 100k but maybe something in
the circuit is lowering it), anyway I will replace it since looks really
unstable wen you trim it.
Tr8 and D1 looks ok, Can IC1 or IC5 be the problem?
Vr9 doesn't exist in my board
pin 1 and 3 of all faders are inverted from schem i've got to real board.

Thanks for any help!
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