> ANY feedline repeats the Load Z (Impedance) every
> 1/2wavelength..remember that must take into account the velocity
factor
> of the feedline...for normal coax its about 66% so 0.66 x 468/freq in
> MHZ = length of 1/2 wl coax at that freq...the only thing about this
is
> you can use ANY feedline bewteen radio and antenna as long as its 1/2
wl
> and the radio will match the antenna (if the antenna is 50ohm +0j
> already)....SWR at the radio will be accurate.....if the antenna is
NOT
> 50ohms or has reactance, the feedline will always cause a WRONG SWR
> reading at the xmtr unless it is a 1/2 wl (in coax)..
wrong. The swr in the coax doesn't change with length, except for small
losses that always reduce it.
The problem is cheap meters or installations that have rf on the outside
of the coax... again, a metering problem. The swr does not change with
length.
_______________________________________________
See: http://www.mscomputer.com for "Self Supporting Towers", "Wireless Weather
Stations", and lot's more. Call Toll Free, 1-800-333-9041 with any questions
and ask for Sherman, W2FLA.
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