searchnig for schematic Threshold Fet one

if that drek is in my workshop , I would find what's the culprit - without asking and replacing everything .....

that's just plain and simple preamp .......



with "everything" I meant on everything in PS section ; it certainly needs recap after all those years ....... and you have - what - few more parts , except caps ...


2007-08-23 4:53 pm
As I said, a lot of transistors (13).
The Caps are all ok. Resistors too.


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Nominal capacitance 1.5 mF, measured 1.9/2.0 mF.
Typical ESR 170 mOhm, measured 120/130 mOhm.

Same advice as "change everything"?


well - you must confess that novice ( who is asking for schm of simple preamp ) isn't supposed to have ESR meter .... and I couldn't know in which condition they are .....

so - to rephrase my self - for proper repair of preamp - replace all broken parts ..... :clown: