On Thu, 2008-05-08 at 15:20 -0700, Jim WA9YSD wrote:
> Lowest loss matching an antenna has to be the antenna that does not
> need a metal composite balun or a tuner and use only Type "N" connectors
> through out.
Nah, 7/16 DIN connectors are lower loss than N types.
>
> With that said, and saw some one say use single band antennas.
>
> Use a COAX CHOKE at the feed point.
Providing you demand all the radiation be from the dipole and don't want
the diversity from the feed line's radiation.
>
> You want a 50 ohm center impedance at the feed point and use 50 ohm coax.
So you raise and lower the antenna to get that 50 ohm impedance?
>
> At this is telling me that an inverted vee would be the optimal antenna to
> use.
>
> If you have a 100 foot tower and a yagi at the top and all what I just had
> said was can be ignored.
The yagi or the double extended Zepp or an array of radiators gets more
RF in a particular direction or two, if the feed system loss is low.
If the feed line is long the losses in a small diameter feed line will
mask antenna mismatches and will definitely affect system loss or
efficiency. And what is long depends on the frequency and the size of
the coax. In years past, 3/4" cable TV distribution cable was a handy
source of a low loss feed line good from DC through at least 1296 MHz.
>
>
> Keep The Faith, Jim K9TF/WA9YSD
>
>
73, Jerry, K0CQ
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