Hi,
I have a Farfisa S-80 amplifier (from B8-80 or
Twin-80 guitar/organ amp), circa 1967, with discrete components. I also
have the Farfisa blueprint schematic. However, two of the transistors are
blown. In the power amp, there are 4 AU103 switching transistors.
However, between these and the transformer are 2 unnamed transistors (SFT
0). These are unusual transistors, with three wires, mounted in the air,
about 1/2 inch long tubes, with no writing and some trace of red. I
am wondering if any other Farfisa amplifier circuits from this era might have a
similar design and better description.
Thanks!
Kirk