Rockman A12-50 Guitar Amp

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CJ

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kind of a rare breed, about 500 made so go the rumors,

Sholtz/Randall product,  solid state with the Ultimtum Distortion Generator circuit,

kind of a nightmare to fix, no schematic on the planet, and the board looks to be heavily modified,  :'(

turns out it is factory modified, wtf, over?

some help at the patent office under Donald Sholtz,  here we go with the front panel of this 50 watt 12 inch combo>

 

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here is a shot of the preamp board, some jumper slots now have resistors, one of the fets is gone, vertical mounted resistors spliced in, caps added across resistors, traces cut to some of the tone controls, double decked switcher chips for quicker response time,  :eek:  whole lotta fun,

 

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so, the challenge is to trace out the schemo since none exist, including the mods,

here is what we have so far, next opamp stage will be the distortion circuit with LED's and diodes and fets,

TL074 is the chip,
 

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Hi, just wondering if you had figured any more out with this amp?
I bought one a few months back and I am experiencing loud popping sound when I drive the input too hard.
 
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