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Old April 20th 04, 10:38 PM
Irv Finkleman
 
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Cecil Moore wrote:

Irv Finkleman wrote:
I used 300 ohm TV twin lead for years. Why the concern about 600 ohms? It
really doesn't matter unless you have a 600 Ohm feedpoint. The losses are
still very low regardless of conditions, and as for dirty or rain, I had
some up from 1983 to 1996 -- and never noticed any changes. When I took
the antenna down the twinlead was as good as new and I used it for other
things.


Here's the 600 ohm concern. A dipole's feedpoint is likely to vary from
about 60 ohms min to about 6000 ohms max. With 300 ohm line, the SWR varies
from 5:1 to 20:1. With 600 ohm line, the SWR is relatively constant
at 10:1, i.e. 600 ohm line gives more consistent SWRs over the entire
HF range than does 300 ohm line - just my two cents.
--
73, Cecil http://www.qsl.net/w5dxp

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Understood, Cecil, but when the SWR losses are of so little concern
then the SWR consistency becomes likewise, at least IMHO.

Irv

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--------------------
Irv Finkleman,
Grampa/Ex-Navy/Old Fart/Ham Radio VE6BP
Calgary, Alberta, Canada