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Old May 12th 07, 02:10 PM posted to rec.radio.amateur.antenna
Yuri Blanarovich Yuri Blanarovich is offline
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First recorded activity by RadioBanter: Jul 2006
Posts: 170
Default Phase Shift through a 75m Texas Bugcatcher Coil


"Richard Harrison" wrote in message
...
The antenna signal travels from the transmitter through the coil and
through the stinger until it reaches the tip where it is forced to
reverse course by the open circuit. All the signal which has not been
radiated or lost in waste enroute starts its journey back toward the
transmitter. This reflected energy from the antenna tip is of no help in
determining delay through the loading coil but the ripples it makes,
when it adds and subtracts from the waveform of the forward energy,
makes measurements difficult. .....

Best regards, Richard Harrison, KB5WZI


Which brings me back to my question: How important is the Q and low
resistance of the coil and stinger? The subtracted waveform (current) seems
to show slight increase at the base of coil, which we are trying to
achieve - prolonging the high current portion along the radiator system.

If we had traveling wave situation along the radiator - almost uniform
distribution (need resistive loading at the tip, just like in Cecil's coil
example or Rhombic/Beverage antennas) - how would that affect overall
efficiency?

When Barry, W9UCW did his experiments and measurements, he was surprised
that quality of the loading coil made hardly any difference. Like good
Bugcatcher coil vs. bad Hustler type resonator.

Do we have the case where some power is being lost for the benefit of
stretching the high current portion along the radiator and making up for
losses?
Normally we always try to minimize the resistive or other loses, but seems
that something "fishy" might be going on, or is it insignificant form
practical purposes, but I still believe that when involving more loaded
elements in an array, things add up and become worthy of considering.
(We are talking about quarter wave vertical resonant radiator not the
Goosian soup :-)

73 Yuri, K3BU.us