>On Mon, 24 Dec 2007 11:42:03 -0600, AD5VJ Bob wrote:
>
>>Will an 1/8 wave vertical work for top band or do you have
>>to start with 1/4 wave? Perhaps top loading it would
>work??
It is just short of amazing what sort of efficiency you will
gain if an 1/8 wave pole is top loaded even with the top guy
wires connected down to 20% before insulators and then
connecting a jumper wire around connected to the antenna
side of the insulators in a skeleton umbrella capacity hat.
This technique drives impedance up at the feed point as long
as the guys do not slope down more than 45 degrees which may
cause cancellation of the top loading effect described.
Perhaps someone will model this break even point but a 60
degree downward slope of 3 25 foot wires on a 65 foot pole
will do well IMO.
Herb, KV4FZ
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