I opened up my SB-220 the other day for the first time (to replace the
diode board so I could see my real HV) and discovered something odd. It
appears to have the Measures mods to the parasitic suppressors in the
anode circuitry (2-turn coils, paralleled resistors, and the 2
unequal-length wires from the plate choke to the blocking cap) but there
are also what seem to be high-voltage resistors in series with the Measures
suppressors, and between them and the plate RF choke. They are pretty
discolored, but the color code seems to be 10 ohms.
Anyone have any idea what this mod is, or what it's for? Could it be
responsible for my low output on 10m.(ca 750 watts)?
73, Pete Smith N4ZR
n4zr@contesting.com
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