Modding 90s PolyChorus to have LED indicator

[Gigahearts_FX]

Mentioned in the DMM thread so making a new one

The 90s poly reissue isnt true bypass, and doesnt have LED indication

TO make it LED indication, you typically need to replace the DPDT switch that is in there:

*note I already replaced the DPDt with a nicer alpha brand version. Yours might look different....

With a 3PDT switch (classic blue 9 pin dealio). Wire it up as per the DPDT. I use a cool O ohm resister as the jumper, but you dont have to:


Next take the red wire that is connected to the PCB at the point marked "LED" and run that to the central lug of the lefter pole of the footswitch. Run another wire from the pole of the footswitch from which the output connections from the PCB are wired (on my pedal, the red and yellow).
As such:


This will allow LED indication.
I find the bypass on mine acceptable. True bypass with LED would require a 4PDT switch I think.

Enjoy!

[hatshirt]

fucking awesome, thanks for the thread!

[bigchiefbc]

I had this mod done to my old school Bass Micro Synth as well. That was back before I learned how to solder and had enough confidence to try it myself. Either way, it's a must.

[Gigahearts_FX]

I had this mod done to my old school Bass Micro Synth as well. That was back before I learned how to solder and had enough confidence to try it myself. Either way, it's a must.

yeah ive done similar on my big box 90s MicroSynth. the difference there was I true-bypassed it also

[braaandooon]

Think I mentioned the polychorus bypass in the dmm thread.

Love me some pics, and thanks for the thread, gonna get this done.

[hatshirt]

did this mod last night and it works great. made a rad pedal even better!!