Building a Wah Pedal NEED HELP

[MattAnonymous]

Hey guys, I'm building a wah circuit (the simple one at http://www.geofex.com/Article_Folders/wahpedl/wah1.gif ) I have gotten to the point at which the 100k audio taper pot will act as a volume control, but there is no wah sound.  I read that the 4.7uf cap may be bad so I swapped it out with a new one and nothing changed.  I'm using the radioshack audio transformer as the inductor and 2n3904 transistors with ceramic caps except for the one 4.7uf electrolitic and .22uf tantalum caps.  What's wrong?

[MattAnonymous]

c'mon guy please help

[Mobisimo]

Could be you didn't ground the 4.7 uf cap.  If you lift the ground on that, it turns into a volume pedal.  I actually put in a switch to do that; its very useful.

[al3151]

Did you use a PCB?If so wich one?

You may also want to check the connections on the .22uf caps as that will give you the volume pedal effect too.Check out the red Fasel inductors at Smallbear or the Dunlop for that matter,those are going to sound alot better than that RadioShack transformer IMHO.

http://www.smallbearelec.com/

[MattAnonymous]

I just used the regular proto boards from RS with the holes and copper circles (cant think of official name).  Anyway I have grounded all the caps that need to be grounded.  Also, should the neg from the bat and two input jacks be connected to the ground?

[AL]

Go to this link and check out the Clyde McCoy Wah link on the left hand side.  There is a lot of good info here and there is a very good layout.  You may need to sub your values but other than that they should be similar.  http://fuzzcentral.tripod.com/

AL

[al3151]

I'm not sure if the .22uf tantalums make a difference if they are polarized but here is another link.

http://www.generalguitargadgets.com/v2/index.php?option=displaypage&Itemid=126&op=page&SubMenu=

[Aharon]

I tried with the Radio Shack transformer (4 of them actually) and it never worked.
Get a proper inductor,I think that that's your problem.
Also there is a proven PCB at Tonepad with the volume  pedal option,Q control and buffers.
Aharon

[Craig V]

If you're using Radio Shack "NPN type 2n3904" transistors where they comes in a box of 15 or something, they aren't all the standard EBC pinout.  I learned this from hours upon hours of debugging a Neovibe.

You may want to buy some transistors from Small Bear, the BC109C's seem to be a popular choice.