>
> I have an opportunity to make a 1100 ft 2-wire Bev on a remote
> site, but
> the wires will be suspended independently in tree branches. Line
> impedance will therefore not be uniform along the length. Do
> you think
> it is better to use open and short terminations or a reflection
> transformer in these circumstances?
>
> 73 + HNY,
> Greg, ZL3IX
Greg,
the difference between terminating and not terminating the beverage or wave
antenna is between resonant - standing wave, and non resonant - traveling wave
antenna.
It is better to terminate it with resistance equivalent to impedance of the
antenna. I would use the reflection transformer for the same reason.
Before analyzers were available, I used to tune the Beverage with antenna
tuner on desired frequency and then replace the antenna with non inductive
resistor bank and while keeping the settings on the tuner the same, I would
adjust the resistance for 1:1 SWR and then read the resistance and use that
value for the terminating resistors.
Fluctuating the height of wire or its direction within few feet is not
significant especially when wire is terminated.
It is good to have short and loooong Beverages, for contester, that brings
different results under varying propagation modes and angles. Staggered or
phased Beverages sure cleanup the pattern and add some gain. Check
http://www.teslaradio.org/w8lrl.htm for some pictures of Wall's beverages and
other hardware.
73 Yuri, K3BU.us
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