W5DXP wrote to W7EL:
Question: Why didn't you use a 75m bugcatcher coil for the experiment?
And why did you put toroid at the base? We are talking about loading coils that
are installed at half to 2/3 up the radiator. Try 12 foot radiator with loading
inductor at ~65% up from the feedpoint. The results should be "magnified". Our
theory is that the current drop across the inductor should be roughly
proportional to
the current in the radiator (in degrees) that it replaces (Cosine law).
Judging by description, I would guess that there wasn't much difference. Put
that coil up but don't use scope probes, they will detune the antenna, no
wires, use thermocouple meters. Probes at the base they probably do not distort
the measurements much.
Nice disertation on engineers and modeling. The only small problem is what and
how you model. If your modeling uses 0 size inductance and real measurement
shows something else, maybe there is a reason to question modeling how well it
reflects reality. I went to university first, I designed parts that human life
depended on, and I would think twice about relying on some numbers without
testing and verifying it. Space shuttle tiles modeled OK?
Yuri
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