Greetings,
Still having fun with my SB-200. Took some time today to look at the input
VSWR on each band. 40 and 20 meters are 1.0:1, 15 meters ranges from 1.4 to
1.7:1, 80 meters is over 5:1--seems like an easy adjustment of the input
tank coils. My plan here is to remove the SB-200 from its case to expose
the input tank coils. Each one is marked in the book as to the band. I
think the safe way to do this is to make a slight adjustment, then fire up
the amp to see what the effect was--slowing getting to where I want it to
be. Is this the best method?
10 meters acts strange. The output oscillates as does the VSWR--not a fast
one but noticeable on the power meter. If I drive the amp hard enough the
relay in the amp will drop out and begin to oscillate as well. Any ideas
on this one?
TU es 73 de Tom, K4NR
PS Just built the small switching circuit (single NPN, two 1K resisters
and a diode) that Rich Measures had on his homepage to use the positive 12
volts from the TS-450 to switch over the SB-200--what a pleasure as I got
to turn that noisy relay in the TS-450 off. Thanks again Rich...
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