Wrong reflector, but I disagree completely with this:
The HV build up was mitigated by the 10pf cap between the 40-20M positions
which also reduces arcing on the SB-220 which is a shorting switch and a
cap can be adapted to some 160-10M amps. The right hand one in that photo
had the 80-40M contacts replaced and Id bet there was still a carbon track
that wasnt removed, you can easily see the deposits all around that wafer;
a good sign of a poor repair tech. Originally a sure sign of high VSWR or
open relay.
Same style wafers as in the SB-220, Clipperton L , AL-80 family and others
that lived on the edge that still arc today. The arcing is usually a high
VSWR, open circuit due to relay, way out of tolerance carbon parasitic
suppressor resistors, mistuning as was likely the cause on the left wafer
on 10M, and CB use since the NCL-2000 was one of their favorites in the
70-80's. Another cause is not knowing how to read the manual tuning
instructions and tuning full bore key down in the SSB position. As built
it was a 1000W INPUT CW amp and 2000W INPUT PEP on SSB. That is about
600/1200W output respectively as was common on many amps of the pre 1500W
output era. Funny how they all seemed to be OK before the rules changed
and switch configurations werent an easy way out to cast blame.....
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