Author Topic: Digitech Whammy XP-100 Powers on but no effect or output  (Read 308 times)

jpistolas

Digitech Whammy XP-100 Powers on but no effect or output
« on: June 04, 2018, 02:56:24 PM »
The title says it all. Powers on, I've done the factory reset but same end result. The one thing different is the only AC adapter I had to test it with is 10vAC whereas the XP-100 calls for 9vAC. Would one volt cause this behavior? I wanted to see if I could get some insight before I purchased a power adapter for a pedal I'm not sure will work properly either way. It was given to mee with a box full of other broken pedals. Was able to easily repair most all of the standard analog pedals but DSP is a bit out of my wheelhouse.

Please, anyone with any experence with these things please chime in.

Thanks-
"The only thing that interferes with my learning is my education."  - Albert Einstein

Prehistoricman

Re: Digitech Whammy XP-100 Powers on but no effect or output
« Reply #1 on: June 13, 2018, 04:46:53 PM »
The extra 1V is normal. Under no load, transformers output a bit more voltage than they're spec'd to.

Do you have an oscilloscope? If not, you can use your amp as one by putting a small capacitor in series with the input. 40nF that kind of thing.
Probe pin 8 of U3. This is the input to the DSP. Any signal?
Probe pin 8 of U4. That's the output. Any signal?

If you've got signal at both of those, check pin 1 of U23 and U5.

Govmnt_Lacky

Re: Digitech Whammy XP-100 Powers on but no effect or output
« Reply #2 on: June 14, 2018, 11:42:07 AM »
Just one quick tip too....

Be sure your Volume pot is turned up. I say this based on experience. Once spent 30 minutes getting ready to tear apart an XP200 only to find out that the Volume pot was all the way down  :icon_eek:

Make sure the pot is not broken or cracked also. I have seen that a few times as well. They are vulnerable to damage from kicking and such. If the wafer cracks or breaks it can cause no output.
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Prehistoricman

Re: Digitech Whammy XP-100 Powers on but no effect or output
« Reply #3 on: June 14, 2018, 11:51:24 AM »
Be sure your Volume pot is turned up. I say this based on experience. Once spent 30 minutes getting ready to tear apart an XP200 only to find out that the Volume pot was all the way down  :icon_eek:

Broken user!  :icon_biggrin: