A tale of 2 Wah Wahs

[PoPo75]

I have 2 crybaby GCB-95 Wah Wah pedals. One is only a few years old and works perfectly with no mods. The other is probably from 1995-96 time frame. It stopped working at some point YEARS ago (I have no idea why). That's why I bought a new one. Anyway, I figured since I had the non-working one I would repair it and/or modify it. I opened up both wah pedals to compare and came up with a ton of questions.

First is the differences; I've done some research on this and for little info except that some time in the 90s Dunlop modified their circuit (some websites say the board should be stamped with a "REV 2" on it) and also changed their board by mounting the input/output jacks onto it.

Here are the 2 back to back:



The one on the right is the older one. Different circuit board but the jacks are still mounted on it. Also, a lot less components on the older one.

Can anyone explain the differences between the two circuits?

My next question is what would be the steps to trouble shoot the broken wah wah? It was working one day then just quit. No sound coming out at all.

[Plexi]

Bigger and closer pics would help 

As I can appreciate at the distance: the older one board doesn't seems to be 'original'.
I don't remember seen some FR1 board in some Dunlop pedal.

I can perceive that they re-build the pcb without Buffer stage/components.

What I would do?
Definetevely, rip off that board, rescue inductor/jacks, and build a McCoy wah.

[thermionix]

If the older wah only has two transistors, it doesn't have the input buffer.  I'm not sure which came first, the input buffer or the board-mounted jacks.

I agree bigger pics would help.

[PoPo75]

I've been reading up on it and found a few resources. The input buffer cam after the jacks being mounted on the board. I would like to trouble shoot this on and get it back to working order.

I posted bigger pics. If you click on them they go to original size.

[Plexi]

As I said, its the first time I see a Dunlop's board of that kind (FR1).
Maybe it's too old?

Can you dismount it, and see what's under on the solder side?

The unit sounds on bypass?
I don't discard that the spdt switch and/or the pot reached their utility lifetime.

[Myampgoesto12]

Did youget the broken one used? If so some folks like myself set the bypass switch kinda high to make it easier to turn it on. This can make it easy to break the rocker inside of the switch. If you have a bypassed tone, but don't have a wah tone it could be the switch. If you have a basic voltage meter with continuity check you can check if it still functions with that. Same for the pot as well. If the pot reads open in certain or all positions of its rotation its bad.

Also it could just be a weak solder connection. Or even possibly a break in a battery wire since its older and can move around when replacing the battery. I had this happen in my Morley, a much newer pedal.

Do as Plexi mentioned about looking at the trace side of the board. If no problems found there it may be age on the components.

Good luck!