WAH PEDAL HELP

[dangb523]

 :ok im building a wah pedal ,and for one of the capictoors (.01 uf and .022 uf), i would like to use a pot to adjust between the two. Unfortuanatly i have absolutly no idea had to do this. technically this is waht i want to do: .01 cap      .022 cap
                                                                                                                                         100k pot

i want to have an adjustably range. COuld someone instruct me on how to do this , or give me a diagram or somthing,


also i would like to kno how to do this with a capacitor, can i replace a 68k resistor with a 100k pot? i read online i could use this as Q control , but i dont kno what gets connected to what ( the pot has 3 metal thingies sticking oout) sry im a noob

thanks!

[Fuzzy-Train]

I think you'd need a rotary switch for that... a pot reaplaces resistors (pot=variable resistor)

I can't help with wiring a cap switch though since I've never done that.

[jonathan perez]

well, rather than a pot, i would suggest a switch. in your case, a DPDT switch will do.

anyone have that diagram? i know i saw it somewhere around here, last week...

[enigmur]

Do you only want to have those two caps in there, or do you want a range of caps from 0.01uf to 0.022uf? \

You will need a rotary switch like this - http://myweb.tiscali.co.uk/nuukspot/decdun/gc/rotarysw.l.jpg
You can get different amounts of positions, I have a 6 position switch - so you could add 6 different value caps. You hook the capacitors up to the outside lug (Depending on how many positions, lets just say 6 positions. I believe it works like lug 1 - lug 7, lug 2 - lug 8 ect.)

Then the middle 2 pins go to where the capacitor would be placed on the circuit board.

By the looks of things you are modifying the 'Sweep' Cap, I would get a 6 pos rotary switch (make sure it has 2 output lugs) and try a broader range of caps - for example 0.01 - 0.048.

If you do only want the two caps you named, you could do this with a DPDT toggle switch.

[Transmogrifox]

also i would like to kno how to do this with a capacitor, can i replace a 68k resistor with a 100k pot? i

You can do that.  You probably want to replace the 33k resistor with a pot for Q control.  I would consider that to be the best choice.

The pot is just like a resistor with tap into the middle of it that can be moved to different positions.  That part is called the wiper.   If you solder a wire between two of the lugs on the pot, then you would have a variable resistor adjustable from 0 ohms to the value on the pot.  For example, you would have a resistor that is variable from 0 ohms to 100k ohms if you did that with a 100k pot.

You may want to put a 10k in series with it, since much lower than 10k would pretty well do away with the wah wah effect. 

[spiderman2812]

I agree if you want different values use the rotory switch. I myself don't like all of that stuff on my pedals so i just experiment and find out what i like best. I recently built an output buffer with a 100k trimpot and decided to remove it and just use the 100k resistor. The whole point was to have control over the volume of the pedal but I've found it is better to lower  the input resistor to around 47k if you go true bypass. They say if you go lower you could pick up radio interference and then you have to add caps to stop that. But it's your pedal Have fun!! Good Luck!!!!