> Some time ago some kind person NU9S I think put out a number of
> responses about this subject. I am trying to get an inverted L for 160
> going. It is over salt water of the intercoastal waterway. The previous
> posts suggested 130 feet was the best length to start. This goes up 48
> feet on a boat house and the rest horizontal. Fed at the bottom with the
> center conductor of the coax to the antenna and the braid to a 240 foot
> counterpoise at 3 feet above the water along the pier directly below the
> antenna. At 130 feet total it resonated at 1.58 kc. I cut off 3 feet and
> it resonates at 1.6 kc. I cut off 4 more feet and it moved up only to
> 1.625. Am now at 122 feet!! Some where I read 127.5 feet was supposed to
> put me at 1.9 kc. . Looks like I will have to cut off alot more
> before I get to 1.9 kc. Am I going in the right direction? Was 130 feet
> too long to start with over salt water? Shall I keep on cutting until
> I get to 1.9kc ? The coax is 350 feet long out there. Any help will
> be appreciated.
> Dick W5AA
>
Hi Dick,
Put up the length of wire that is resonant by the formula for the frequency
on interest. Then cut the counterpoise to resonate the system, not the
antenna wire. I would install a choke balun at the feedpoint to keep the
shield of the coax from acting as another counterpoise.
GL!
Phil, K5PC
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