Hello
Am 09.03.2012 14:24, schrieb dir_marillion:
> Is the TL072CP under the capacitors (inside the circle) ?
Yes. There are two, but the one which affects VCO4 is under the second
bentover capacitor (counted from the bottom of the circle).
> Do you suggest to replace the TL072 or I may have a damaged 4006 ?
There is a basic principle of search for faults: never change two things
in the same step.
So the order of steps should be:
∗ Replace IC10 (TL072)
∗ Check the portamento of voice 4
∗ If it does not work: check the fourfolded portamento potentiometer, in
case of doubt shortcut in each layer of the potentiometer the two outer
contacts
∗ Check the portamento of voice 4
∗ If it does not work: insert a cable into the portamento socket (this
switches the 4066).
∗ Check the portamento of voice 4
> Second question. As VC04 is also detuned about 4 notes and I do not
> have the KLM398, which are the switches for the 4rth VCO that I have
> to tune ? I show two white circle tuners under the fourth VCO (check
> my uploaded picture).
You don't need KLM398, but only KLM354. I described the tuning procedure
in detail at
http://fa.utfs.org/diy/korg_monopoly/vco_adjustment.htmlI would NOT do the full procedure, but simply try to change the offset
with VR402
See
http://fa.utfs.org/diy/korg_monopoly/mp_16_klm_354_layout_TRIMMERS.jpg the most left light green marking at the bottom named with "tune offset"
Florian