Another benefit of using twisted pair wire or WD-1A is the
lower Velocity Factor (VF) of the wire: a physically short
antenna “looks” electrically much longer. Using a VF of 58%
for example, a 311 foot long twisted pair antenna is
electrically the same length as a 537 foot single wire (one
wavelength) antenna on 160 meters.
So if I were to use the .58 velocity factor on a 440' single
wire 80M beverage, I should expect to get the same
performance from a 255' twisted pair beverage. Am I
understanding this correctly? Or is there some downside
that I'm not accounting for?>>>
The statement is absolutely incorrect Brent.
The velocity factor of the wire in a transmission line mode
has nothing at all to do with the electrical length of the
antenna.
Only the common mode currents in the wires, where the
currents are parallel, can act as an antenna. Those currents
are unaffected by the differential (across) slowing caused
by the majority of insulation being something other than
air. So a 300 foot long antenna made from .66VF coax or
twisted cable acts exactly like a single conductor Beverage
of the same outer insulation and diameter.
There is no advantage for receiving.
73 Tom
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