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Oberheim Ob-1 SEM oscillator.

Oberheim Ob-1 SEM oscillator.

2008-10-01 by SynthX SynthX

Hi,

I am having some problems with two synthesizers that I am trying to
fix.

The first one is an Oberheim Ob-1 where the square wave on Oscillator 2
in the "Fund" mode is not strong enough. I have replaced all OPamps 741´s
one CA3080 and all transistors (3905,4302, 5172 ...) But still the Square
wave is very low in volume. Any ideas what to look for and where ?

I also have a SEM module where oscillator 2 wont sound att all, weird thing is
changing the tune on oscillator 2 results in a tune change on oscillator 1 (which
does work). Everything in OSC2 is replaced but not resistors, diodes and a few
caps. I´ve even tried replacing the CA3086 but nothing commes out of this module.
Any ideas what and where to look next ? (The mix potentiometer on the front is
measured and it works btw). (Oscillator1 is sounding fine though).

Hitta någon att mysa med i höstrusket! MSN Dejting

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