I received about a dozen E-mails asking for the size of the coils. The coil
reactance will vary quite a bit with the impedance of the antenna.
When I was experimenting with my loaded Beverages it was in the 70's, and the
data is long gone. I used sampling probes and a Vector Voltmeter to measure
phase delay (with some long matched lines) and it would be unlikely that
anyone could duplicate that.
As I recall the coil reactance was around 800 ohms at 2 MHz, the termination
impedance was well over 1000 ohms, and the wire was #16. Someone may try
modeling this, with loads spaced every 1/8 wl.
Series inductive loading raises the impedance and slows the velocity of
propagation in the wire. The slower velocity of propagation increases the
directivity.
Sorry, but it was an antenna I never kept many notes on.
73 Tom
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