Hi,
I m trying since 3 weeks to test some reduced size beverages .
I have roll 180m of wire on a 20mm PVC plastic pipe at 20cms of the ground
of 24m long .
Best match with 50 Ohms cable was around 240 Ohms so I've used 7:1
transformer to match.
Resistivity of my used wire on total length is 12 Ohms.
Actually the Beverage is not load , so bidirectional ,results are nice
compare to my EWE , but I planned to do a reversible system on single wire.
I saw an article from W8JI in the "Communications quarterly , spring 2007
page 103" that it is possible to feed both side of the antenna . So the rx
direction of the antenna will change cause system with be load or not on
both side.
But in this kind of system w8ji write : ". termination resistance is made
equal to the coax feed line's impedance. The transformer step the
termination impedance up to the proper value, just as they step the
receiving end's impedance down to match the cable".
So if I understand it is better to use some 75 Ohms cable than 50Ohms to
lift the termination, so have more effect !!??
May somebody has ever done this system . and can donate own opinion.
Thanks in advance.
B R 73s
Damien F4AZF
www.f4azf.com <http://WWW.F4AZ.COM>
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Topband Reflector
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