Sorry to hit more than one reflector, but this one really seems to straddle
both.
I have an SB-220. This morning, I measured the SWR curves of my Force 12
C-3 through the SB-220 (with the amp off) and then with a barrel connector
replacing the amp. To my surprise, there was a huge difference! For
example, on 20m. with the amp in the line the SWR minimum was at 14.4 mHz,
with very broad frequency response. With the barrel, it was at 14.2 and
the frequency response was much more like what one would expect.
For the antenna folks - can you suggest a theoretical explanation? It
seems counter-intuitive that a foot of coax and two sets of relay contacts
inside the SB-220 could have such a major effect.
for the amp-heads - What should I be looking for inside the SB-220 that
might explain this? I'm a real neophyte with amps, and I don't want to go
in any blinder than necessary.
Thanks in advance.
73, Pete Smith N4ZR
n4zr@contesting.com
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