#1
i am having problems with my wah. Can i test the pot in it with a multimeter? how would I do this? will i have to un solder it?
#3
ok I just true bypassed my crybaby wah by following the instructions on here and im now having some issues. the true bypass works great but when i turn the wah on it doesn't sweep any. it just sounds like its in the heel up position and never changes. could I have ruinned my pot? is there something else that could be wrong? could I test it with a multimeter? I really need some help here. thanks
#4
Quote by Alex88
ok I just true bypassed my crybaby wah by following the instructions on here and im now having some issues. the true bypass works great but when i turn the wah on it doesn't sweep any. it just sounds like its in the heel up position and never changes. could I have ruinned my pot? is there something else that could be wrong? could I test it with a multimeter? I really need some help here. thanks


If you have a resistance check on your meter then yes.
Power down the unit and probe the two outside lugs to ensure the componants actual value is what it should be. This can be done with the pot installed. The intended value will be written on the pot or be in the schematic, I think it's 100k for the Dunlop wah if memory serves me right.
Then take one of the probes to the centre lug, wiper, and turn the pot knob to ensure the values are changing as expected.
If it passes this test it's OK.
Did you change any other parts on the board at the same time?
#6
Quote by Alex88
ok so i tested the pot and it read 100k but it didn't change when I turned it. I removed the buffer on the circuit board. I followed these instructions.

http://www.indyguitarist.com/mods_new/Dunlop_wah_true-bypass.pdf
thanks


When checking for the value changes did you connect one test lead to the centre lug or wiper? If still connected to the two outside lugs you wont see any difference.
Do you do the vocal mod?
#7
umm this pot has the lugs in a triangle formation so there isn't really a center lug and I dont know what the wiper is. Yes I did the vocal mod.
#8
The wiper the connection that moves as you turn the pot. It's connected to the center lug. My guess is that perhaps you connected the lugs on the pot incorrectly. I'd double check that.
#10
Quote by Alex88
I didn't disconnect the wires from the lugs on the pot.


Ah I forgot what pot the wah has. The one with the black wire goes to ground so connect one test lead to it and probe the other two until you find the one that changes in value, that my friend is the wiper.

As you didn't disconnect the wires and the outer lugs are reading fine I'm willing to guess it's OK anyway.
I'd be looking more for cold solder joints where you did the vocal mod.
Look for loose componants, greyish bubbly solder and also use your multi-meter to trace continuity between each point you worked on.
What value did you use in place of the 33k?
Make sure it reads that value with your MM.
Ensure there's continuity between between the resistor wire and the trace underneath the board, your meter should read a very low ohm value if it's ok, mine reads .4 normally (leads shorted) and also .4 on a good junction.
Also check the componants where you removed the input buffer. Do you have good continuity between the switch lug and the point you've entered the board? What about the entry point to the rest of the effect.
I know it sounds dumb but did you reconnect the ribbon cable properly? I've noticed if it's not seating right the bypass works fine but with the wah on you get a volume drop and a dull tone.
Double check all your work in this fashion and I'm sure you'll find your problem.
#11
Quote by Alex88
I didn't disconnect the wires from the lugs on the pot.

In your first post you said that you modded the wah for true bypass. This is why I assumed that you had disconnected the pot. I'm not aware of how you would get true bypass without replacing the stock SPDT with either a DPDT or a 3PDT. If you've got some magic up your sleeve, could you enlighten me?
#12
What I ment was that I didn't connect the wires from the pot its self. obviously I did from the switch. I will check that stuff when I get home from work today paolo.
Thanks