[Antennas] How can I keep RF off rotor cable when loading tower

Tue Aug 17 21:17:37 EDT 2004

Hi all,
Still working on loading my tower that is on insulators. Currently loads nice
on 80 between 3MHZ and 4MHZ. Reviewing the tower is Universal 40ft with AL 
mast,
rotor, 6mtr beam and 2mtr beam. Do have radials in the ground. Keep adding 
more...
Seems to load nice except RF coming down the rotor line (and assume the 2 
and 6mtr coax)
Have to disconnect the rotor cable if testing the tower. Are their 
isolators for this??
Want to add 160mtrs probably as inv-L and assume need trap or relay at top 
to switch between.
Wild thought here as follows:
If tower and ant on top now load at say 3.5MHZ this is 1/4wave vertical 
(equv to prox 60ft) and
I added approx 600ft from top horizontal to some trees that would make the 
ant system 5 - 1/4waves
on 160 and 11 - 1/4waves on 80. Since these are odd 1/4waves I shouldn't 
need a trap or relay at
top of tower right?? I understand the feedpoint resistance would go up but 
don't know much other than
that. Would like to model this but since I am just starting to learn the 
EZnec program will
be too far out for me.... HI...
Maybe you guys can enlighten me if I am headed in the right direction or am 
I going downhill here.....
By the way I can't afford this as an option which is for sale::::
http://www.k4ja.com/
Tnx agn for all the discussions here.
Phil W9IXX (/4)
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Philip Florig e-mail:pflorig at ieee.org
115 Horne Rd. (or):W9IXX at arrl.net
Columbus, NC. 28722 amateur radio:W9IXX
USA also:C6AXX-J3X-T30,31,32,33P-VP2MPF
 team member:AH1A-C6DX-J3A-VP2MX
 MARS:AAM4ENC/AAR4XX
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