Vintage Synth Repair

With the panel face down and open and separated from the base.


On the main board, immediately to the left of the transformer fastened to the back and the spacer bar are 5 solder points in a row at the edge of the pcb.


Starting from your left looking down with the din /back facing you and knob side down, the colours of the original wire, left to right are:


yellow, green, orange/red, black, and, white (closest to teh mount brace and transformer.






On the din socket with the notch on the left,


bottom (top w knobs) of the socket, from the left white and black


then yellow (left ) (on mine another yellow* with the Green, and slightly below the orange.





So from the base of the unit, notch to the output side, From the bottom the circle is:


yellow, green, orange, black, white.  White is now immediately below the factory yellow wire.


Screw to case one below and one above the locking din female socket.





Two cool Mutron Mods:





My yellow * is soldered onto the green at the din jack.  It goes to a cv In jack.  No ground needed.  Jack is grounded by contact to the case.





To the left 1/4" of the pcb line of 5 is a double row off three just above say 1" in from the pcb edge for a switch.  I tap off the middle left to get the Cv for LFO1 out.





I drilled and put in a jack for each, one above the other with lfo 1 on the bottom.





Phaser out A & B are grey wires that go to the pcb.  Sorry need a camera for that.





I use the cv in to send S&H to my phaser (an old Oberheim trick from their guitar phaser pedal).  It sounds very cool and rhythmic.


I think I got the mod out of an old PAIA issue.


cheers





Lorne in Canada  ( in memory of Kevin lightner, who also shared)





From: vintagesynthrepair@yahoogroups.com [mailto:vintagesynthrepair@yahoogroups.com]
Sent: October-17-14 11:56 AM
To: vintagesynthrepair@yahoogroups.com
Subject: [vintagesynthrepair] mutron biphase din jack wiring








hello,  I just bought a replacement din jack to replace the one removed from a mutron biphase.   But because the wiring was disconnected..  I do not know the pinout of the din jack.   the schematic shows 3 of the 5 connections to the pedal,  but the others are not labeled.





anyone have the pinout or have a picture of the din jack from the back?





I have searched the internet with no luck,  any help would be much appreciated.


-steve