Tweet
1973 fender silverface twin rebuild project rewired to 1965 blackface. Hum balance pot rewired to bias control pot. Problem is reverb control knob is also controlling overall volume turning reverb to zero position turns volume off. It is behaving like a master volume. Why?
-
-
When you rewired it, did you include the 470k resistor from the reverb pot to the mixing stage? -
yes I rewired the whole amp with teflon coated 20 gauge wire and followed the schematic at every point numerous times.Comment
-
is that 470k possibly a 47k?Comment
-
No its a 470 K that is what the schematic showed. I replaced all electrolytic capacitors and resistors.Comment
-
Does the control more or less smoothly turn down the volume, or does it more or less leave the volume alone and then kill it suddenly when you hit zero? (That would indicate something in the pot shorting to the cover or a stray bit of wire stranding.)Education is what you're left with after you have forgotten what you have learned.Comment
-
It turns volume down smoothly just like a volume controlComment
-
Sounds like you've got no dry signal. There is a 3M3 mixing resistor bypassed with a 10pf cap. Make sure the dry signal circuit from the .02uf coupling cap has continuity to the mixing resistor.Comment
-
Then something almost HAS to be mis-wired.
Is this what you converted it into?
http://www.schematicheaven.com/fende...b763_schem.pdf
The most obvious guess would be that the wire from the center leg of the reverb control went to the wrong end of the 470k.Education is what you're left with after you have forgotten what you have learned.Comment
Comment