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Can't Get Wha to Work

:

12/8/1999 7:51 PM

Can't Get Wha to Work

I built a Wha circuit board using a homebrew pcb from JD Sleeps site which is, I guess based on a VOX847. I installed
all the trim pots but not all of the switchable
caps (I just put in the 10n stock one). I used
the inductor (TDK) and NPN transistors from my
old crybaby. I hooked up the pot, jacks
and battery w/o the switch to test it out plugged
in a guitar and amp and...nothing. I checked for
bad solder joints, improperly place components, bad
traces, used a different battery, reversed the orientation
of the transisters but still got nothing. I would
appreciate any help.

Thanks,
jc

12/8/1999 8:19 PM
Joe Fuzz	JC: Just a couple of guesses but: 1) Check the harness. Compare it with the diagram on the Fulltone site (if applicable). 2) Connect an ohmmeter between the two pads that the inductor is soldered to. In other words, 2 legs go to one pad, the other 2 legs go to another pad. What does it read between those two separate pads?

12/8/1999 8:33 PM

So that I understand - you desoldered and removed the transistors from your old crybaby, and installed & soldered them into this one?

Two possibilities leap immediately to mind

1) cooked 'em with all that heat (one of my greatest talents)

2) Wron orientation - did you go by pin number or by which pin went to which next component? As noted in an earlier thread this is an easy place to get disoriented.

That said, I hope Mr Fuzz has the correct answer.

12/8/1999 8:43 PM
jc	I have a multimeter that has a transistor checker. The only way I could get any numbers out of it was when the transistors were in the npn side. The display showed an hfs of ~300 for both of the transistors. I checked them as I was reversing the orientation too. I assumed that this means that they were still good. Jack

12/9/1999 12:21 AM
Don Symes	That's good. It's down to solder joints and basic wiring (and wrong values). Patience, and good luck.

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