[Elecraft] Antenna Theory
Vic Rosenthal
[email protected]
Thu Mar 25 12:35:01 2004
Mike McCoy wrote:
> Since there seems to be no clear advantage to using coax (other than the
> fact virtually every piece of equipment made has a SO-259 on the back) why
> then is coax THE most prevalent feedline in actual use?
1) It is unaffected by nearby conductors. It can be run through metal
conduits, taped to a tower, even buried (if you get the right kind of
jacket).
2) An unbalanced tuner is much simpler and cheaper than a balanced
tuner. If the SWR is moderate, then losses are acceptable.
3) An unbalanced output circuit in a transmitter, especially a multiband
transmitter, is much simpler than a balanced one.
4) Given 2 and 3 above, there is likely a need for a transition from
unbalanced to balanced -- and as many have pointed out, this can be
difficult to achieve efficiently in a multiband system.
--
73,
Vic, K2VCO
Fresno CA
http://www.qsl.net/k2vco