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Vibrato Project...

12/27/1999 2:16 AM
Rob W.	Vibrato Project... Hello All!!! After having enough holiday cheer, I decided to venture back to the bench today... My recent project is to install a 6G16 Vibroverb style vibrato into my AB763 Twin. (The opto died recently, so i felt a change wouldn't hurt The install went off without a hich, the new bias modulating vibrato sounds much better, but I am encountering a small problem. I installed a SPDT 250K-L Intensity pot, so i can disconnect the vibrato effect when not in use. But, when I disconnect the circuit, I get this annoying sort of hum!!!! ;-( I have had no luck in trying to trace this problem down yet... I guess that I can leave the vibrato on all of the time, but that defeats the nifty disconnect pot.. ( By the way, the disconnect circuit is designed to just pass the bias voltage around the pot, uneffected in theory from the vibrato circuit...) Suggestions / Ideas???? Cheers! Happy Holidays! Rob W.

12/27/1999 2:16 AM

Rob W.

Vibrato Project...

Hello All!!!

After having enough holiday cheer, I decided to venture back to
the bench today... ;-)

My recent project is to install a 6G16 Vibroverb style vibrato into
my AB763 Twin. (The opto died recently, so i felt a change
wouldn't hurt ;-)

The install went off without a hich, the new bias modulating
vibrato sounds much better, but I am encountering a small problem.
I installed a SPDT 250K-L Intensity pot, so i can disconnect the
vibrato effect when not in use. But, when I disconnect the circuit, I get this
annoying sort of hum!!!! ;-( I have had no luck in trying to trace this
problem down yet... I guess that I can leave the vibrato on all of the
time, but that defeats the nifty disconnect pot.. ;-)

( By the way, the disconnect circuit is designed to just pass the
bias voltage around the pot, uneffected *in theory* from the
vibrato circuit...)

Suggestions / Ideas????

Cheers!
Happy Holidays!
Rob W. :-)

Replies:

tboy Rob,A defeat switch... -- 12/27/1999 10:43 PM
Scott Swartz I can't tell exactly how you hooked... -- 12/27/1999 10:56 PM