could someone lend me a quick look at this wurlitzer schem?

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dramadisease

Well-known member
Joined
Jun 17, 2004
Messages
110
Location
portland - or
I have been working on this Wurlitzer 140 for a bit now and im at a juncture that requires some help. heres a copy of the schematic.
basically my problem is that the signal from the keyboard mic (main input) reaches the base of T2 and then goes nowhere. doesn't pass the signal. now heres the tricky part, if i put an oscillator into the phono input at about the same amplitude (maybe a small bit more) t2 works fine. the voltages on the transistor are about the same, nothing too wierd.
i did replace those varistors, though im not 100percent sure of their function, (they were cracked and old) with 1k resistors just to see if that would bring the unit to life, and though that section seems to be working properly, i still have this problem in the second preamp stage.
any thoughts?

-bryan sours
wurlitzer.jpg
 
The varistors act as a VCA for the tremolo. (Variable shunt resistor in a voltage divider; shunt is split into two paths with opposite CV polarity, to avoid thumping.)

JH.
 

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