[sdiy] MN3007 Chorus Acting Weird

[Jacob Watters]

I am repairing a Yamaha KM602 mixer, which has a builtin MN3007 circuit.
The chorus circuit behaves a bit odd. Instead of being a modulated delay
that causes a pitch shift, it seems to behave like an auto-pan circuit. The
sound level increases on one side, while decreasing on the other, and
alternates back and forth. It is labelled as CHORUS on the front panel, so
that is not the behavior that I expected.

Is this normal, or is something wrong with the circuit?

I tried finding a pdf of the service manual online, but I was unsuccessful.
Does anyone have the service manual and can provide some input as to how
the circuit should work?


Thanks for your help!

Best regards,

*Jacob Watters*
JacobWatters.com <http://jacobwatters.com/>
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://synth-diy.org/pipermail/synth-diy/attachments/20250215/76f3b90e/attachment.htm>