I bought an SB220 amp that wasn't putting any power out on 10 meters, but
1200 to 1300 on 20 and 15 mtrs. It turned out to be a fried bandswitch on
10 thru 20, but was hanging on with a hair on 15 and 20. I replaced the
bandswitch and while I was at it, i installed Harbach mods. (parasitic
suppressor, soft key, soft start, and rectifier-metering board kits) I also
installed new resistors across HV caps from Rich Measures yesterday. Now
on 20 it will arc a bluish color on bandswitch when driving it up to abt
300 watts out. I tried it on another band(I think it was on 15) and the
exact same thing. I noticed that the tune control on 20 mtr tuneup was
peaking out at the 10 mtr position(knobs are installed correctly). This
tells me that there is too much inductance in the circuit.
Has anybody had this problem and can tell me what I should look for??? I
checked the bandswitch and it is installed correctly. Thanks
73, Bob
KQ7J
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