These are all good points an I might add the following:
A 2:1 swr could mean either the rig is seeing a 100 ohm load or a 25 ohm
load. It's those low impedance loads that tend to drawl excessive current.
Be careful when operating with a short antenna. For example, using an 80
meter dipole on 160 meters or a short mobile antennas can show what appears
to be a decent swr while jerking huge amounts of collector current.
TT rigs do have rugged final amps and so far, knock on kenwood, I haven't
blown one, even without a circuit breaker in line, but be sure to adjust the
tuner with the lowest power possible then crank it up after obtaining a
match.
Other make rigs have "foldback circuits" which reduce final power
automatically when presented with a mismatch. This has probably saved many
finals from loosing all their smoke. I smoked the coils in a TS-940's tuner
once when trying to match the aforementioned antenna!
Steve Ellington
N4LQ
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