Just thinking here - I can hold my hand on a 75 watt lightbulb for a few
seconds. 10 of those lightbulbs-worth of heat isn't very much heat,
dissipated over the surface area of the bark of a tree, 60 feet tall, in
winter, with low temps, and maybe even some wind can't really have much in
the way of visible impact, could it? Gone up in flaming glory?
Good logical thinking. It's difficult to know a 6 dB change without
measurement, let alone three dB.
Take a tank coil as an example. Even 50 watts of loss could make it smoke or
melt if the loss is concentrated in one small area, say just a few turns.
If loss is spread over enough area, even 1000 watts power loss might not be
noticeable.
This not only applies to trees, it applies to everything from ferrite cores
to transmission lines. 0.1 dB loss in a coax connector can melt it down
at amateur power levels, 10 dB loss in a 100-foot cable might be
unnoticeable.
73 Tom
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Topband Reflector
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