Hi

>> Yes, you are right; it is exactly as you said.
>> http://www.2shared.com/fadmin/26610218/4b21bac3/monopoly.zip.html
> Aaaah! Things become clearer. I have to track the things in reverse. I
> will come back later.

ok, I had a look at that:

Both groups of additional parts appearently are NOT modifications, but
they seem to be the standard wiring of the very first series. (in my
MonoPoly the same connections exists, but they are achieved as traces on
the pcb!)

The one on the VCF board is the the circuit around Q10, R85, R86, D7,
and C27.
The one on the bender board is the regular wiring of the Arpeggiator
Off/On/Latch switch.

The unused connector on the VCO board is appearently only a kind of
testsocket.


My most likely suspect is the portamento potentiometer itself. You wrote:

> During the procedure, I checked all the Portamento pot lines, with
> a polymeter and they work.

If you measure the lines, then you won't recognize if the slider of the
potentiometer itself is broken. Did you try to shortcut the portamento
potentiometer for vco4

Florian