by EWBrown » Wed Jul 21, 2010 10:26 am
I tried, but that didn't have the "spam" and "RAOTFLMAO" smilies
I copied the last row photos which showed the stuffed and loaded PC bpards.
It didn't take me too long to figure out the rather simple circuitry, after all with only 10 resistrors and 4 caps per channel, it wasn't too daunting a task. And two of the resistors (330 ohms and 1K, 3W) are connected in parallel to act like a 250 ohm resistor.
I suspect that a 12AX7 would be a better match than 12AU7 for the VA/PI circuit. I'll run it through Tube-CAD to determine which is better.
It's basically nearly identical the "K-502" or "K-12" schematic, just with different resistor values, bigger tubes, and no obvious NFB loop - at least its components are not on the PC board. Nothing fancy, nothing special, pretty much a "textbook" design with no originality.
/ed B
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