I have the replacement capacitor in my SB-220. I wouldn't call it heavy duty
but the spacing is wider than the original SB-220 tuning capacitor. I have had
no problems with the band switch arcing in my amplifier. However, my plate
voltage seems to run a bit lower than some other SB-220s I have seen.
I highly recommend that you solve your arcing problem before you put in the
replacement capacitor. File down and smooth out the plates in the original
capacitor first using very fine crocus cloth. It may be that your parasitic
suppressors need to be replaced. The original carbon suppressors age and change
value over time. I replaced my suppressors with ones I found at Dayton a few
years ago. I think they came from either an L4B or an L7. They are comprised of
three, 120 ohm, 2 watt resistors in parallel. The coil is 3 1/2 turns of tinned
bus wire wound around one of the resistors. My SB-220 is unconditionally stable
on all bands, including the WARC bands.
73, Dennis W0JX
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