Wah Cap Mod

[soupbone]

I was doing some modding to my crybaby wah.I decided to go with using a dpdt toggle switch to change between two differen't sweep caps.I was going to use a .01uf(stock cap)and .022uf cap(like the zakk wylde crybaby).I really like the sound of a .033uf cap too.(the Dunlop Hendrix Wah).Is there some way to be able use all 3 without having to use a rotary switch?

[italianguy63]

Use a 1P3T slide switch, but makes mounting a bit more difficult.

[dwmorrin]

Use a DPDT center off toggle.
Wire the common (center) terminal of the DPDT to one side of the original 0.01µF cap.
Wire one side of the switch to another 0.01µF cap.  Return this new 0.01µF to the side of the original cap that isn't connected the center terminal.
Wire the other side of the switch to a 0.02µF cap and return this to the same place as the 2 0.01µF caps.

When the toggle is in center off, there is no connection, and you have the original 0.01µF value.
When the toggle connects the new 0.01µF, it is in parallel with the original, resulting in a 0.02µF value.
When the toggle connects the 0.02µF in parallel with the original, the resulting value is 0.03µF.

[pinkjimiphoton]

+1

exactly what i was gonna say!!

[soupbone]

+1

exactly what i was gonna say!!

Cool!You said it results in a .03uf.Did you mean .033uf?That was the cap size I was going for.

[dwmorrin]

If the original is 0.010µF (the extra zero is intentional),  you need a 0.023µF cap to get exactly 0.033µF.
You can make this by putting two smaller caps in parallel.
Examples: 0.022µF cap + 0.001µF cap (aka 1000pF cap), or a 0.020µF cap + 0.002µF  cap (2000pF).

Or you may find that the 0.022µF, which combines will the 0.01µF for 0.032µF is close enough for your tastes.

Capacitance meters have become very common on even cheap DMMs... if you have one, check the values of your caps, because you may have 0.022µF marked caps, that actually read 0.021 or 0.023.

Of course, this is only if you really want that kind of tight tolerance.  I'm not sure how tight it has to be for your application.  You may use a 0.020µF and be satisfied.  Use the paralleling trick if you need an odd value, and let your ears guide you.

[soupbone]

If the original is 0.010µF (the extra zero is intentional),  you need a 0.023µF cap to get exactly 0.033µF.
You can make this by putting two smaller caps in parallel.
Examples: 0.022µF cap + 0.001µF cap (aka 1000pF cap), or a 0.020µF cap + 0.002µF  cap (2000pF).

Or you may find that the 0.022µF, which combines will the 0.01µF for 0.032µF is close enough for your tastes.

Capacitance meters have become very common on even cheap DMMs... if you have one, check the values of your caps, because you may have 0.022µF marked caps, that actually read 0.021 or 0.023.

Of course, this is only if you really want that kind of tight tolerance.  I'm not sure how tight it has to be for your application.  You may use a 0.020µF and be satisfied.  Use the paralleling trick if you need an odd value, and let your ears guide you.

Cool!Thanks!

[dwmorrin]

Here's a wiring diagram for you, soupbone.
Make sure the switch is CENTER OFF (no connection in center position), and you can use either a DPDT or a SPDT (we only need one pole).
It should not matter which side is the common side (all the caps tied together) or which side is switched.
You could mount the new switches directly to the switch terminals if there's no easy place to mount them otherwise.

[soupbone]

Here's a wiring diagram for you, soupbone.
Make sure the switch is CENTER OFF (no connection in center position), and you can use either a DPDT or a SPDT (we only need one pole).
It should not matter which side is the common side (all the caps tied together) or which side is switched.
You could mount the new switches directly to the switch terminals if there's no easy place to mount them otherwise.

Thanks!What program did you use for the pic?Just curious,-soup

[dwmorrin]

DIY Layout Creator
It's the top post (sticky) in this forum section. 

[soupbone]

DIY Layout Creator
It's the top post (sticky) in this forum section. 

Cool.Thanks!