No wah in my wah

[Blenji]

Hey.

Ive recently aquired an EH FuzzWah.  It has a small problem tho, it has no wah.

There is a faint wah when the fuzz is switched on with it, but alone there is none, just clean tone.

I guess its just a part needs replacing but im unsure as to what.

Any Suggestions?

Thanks.

[jonathan perez]

first suggestion:

measure and post values

[Blenji]

Measure what in particular?

[captntasty]

http://www.diystompboxes.com/smfforum/index.php?topic=29816.0

[R.G.]

Read "Debugging; what to do when it doesn't work."

[Blenji]

Thanks guys.

[Paul Marossy]

If it's an inductor based wah pedal, assuming all the wiring is solid, it's probably either the 4.7uF cap to ground or the inductor could be damaged. Both of those will make a wah pedal a non working wah pedal. The bad cap would make it sound kind of like a volume pedal and a bad inductor will make it so that the circuit doesn't do much at all.

[jonathan perez]

my vote is for the eletrolytic...

wanna make a bet? 

[Paul Marossy]

my vote is for the eletrolytic...

Most likely. But I have recently acquired a wah pedal that had a whacked inductor, so it's not impossible. It happened to be an El-Rad inductor, which I believe was also used in the EH wah pedals...

[jonathan perez]

i took one apart the other month, and im trying to find the core...tearing that sucker apart was HARD. i figured it was hollow plastic. NO SIR. filled with this super rubbery type stuff, but the inductor was similar to those found in some old radios, with the lead wrapped around vertically, versus horizontally.

i had that problem too, but i was a broken jumper...i look forward to seeing what the problem is.

[Blenji]

Hey, Thanks again guys.

Ive gone over it with a Multimeter and theres a 10uf capacitor coming off the inductor to ground.  Between the inductor and cap its registering 0.61 then cap to ground is 0.

I guess this means i just need to replace the Cap?

Cheers.

[Paul Marossy]

Yeah, replace the cap. That's probably the problem right there.

[Blenji]

I dont know if this is asking too much but im interested in learning, but how would this cause my wah not to wah?

Thanks.

[Paul Marossy]

how would this cause my wah not to wah?

Basically, because the cap is internally shorted, it sends the signal straight to ground. As a result, when you use the pot, it acts more like a volume control.

[Blenji]

So if it was working properly, how would it give it the wah effect?  What properties does it have?

[jonathan perez]

http://geofex.com/Article_Folders/wahpedl/wahped.htm

[Paul Marossy]

If you follow the link above, it will tell you everything that you ever wanted to know but were afraid to ask about wah pedals. 

[Blenji]

Thanks for the link.

Ive tried 2 different capacitors and theres still no signal.  Theres signal going in to it (the capacitors) but not out.

Any ideas?

[jonathan perez]

what capacitors (value) did you use?

[Paul Marossy]

OK, then, check the voltages on the transistor pins. One of the transistors might be a dud.