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Fuel tanks and SSB counterpoise.
In article ,
(Ron Thornton) wrote:
Well I guess if I tried to push 30 mhz thru a 2 mhz transmitter you
could call the transmitter a choke too. But in reality it ain't and
the coil in the middle of an antenna ain't either. What you describe as
a choke is a tuning inductor, the choking is an inconsequential behavior
of the tuning at a frequency the antenna was never designed to operate
at.
Ron
Ron, Ron,
Loaded Whips, are just that, wires with a big coil in the middle, that
effectivly lengthen the antenna. They are designed to be 1/4 Wavelength
at the Designed Frequency. ( Morad 2800 & 3400 ect) these can be
resonated as 3/4 Wavelenth at higher HF Frequencies very easily by
adding output shunt capacitance in the tuner. The coil does decouple
the antenna above it at something near 4X Designed Resonance. These
type of antennas have been around in Marine Radio for 50 years, and
Eddie Zanbergen RIP (Chief Engineer @ Morad) designed, built, and sold
them throughout the world, and the properties of Impedance vs Frequency
are well documented for them over the years. After one tunes the old
fixed tuned Antenna Tuners, common in the Marine Radio Service for 20
or 30 years, you get a feel for how they tune and how they work. They
DO tune up very well, and ARE as effecent as any other Marine Antenna
System. Been there, Done that, on hundreds of vessels from 20' to 1200'.
Bruce in alaska
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add a 2 before @
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