Gain is not VSWR is not Feedline Loss. They are three completely separate
issues.
Doug's point is taken from the overall *system* point of view whereby net
effectiveness is reduced by high VSWR. Possibly true, but the solution is
to determine your overall system goals and then begin to assemble
components in such a way as to achieve them.
Only by understanding component performance and the interfaces between
components can a successful system be built. Our tests address only
component performance - that of the antenna. There are plenty of good
articles on feedline and transmission line matching to help with the rest!
I should never write email at work :-)
73, Ward N0AX
On Tue, 21 Jul 1998, DOUG WALLER wrote:
> Yes, but remember, impedance mismatches reflect some energy back down the
> feeder that could have been radiated by the antenna. Doug - Nx4d
>
> Jim Reid wrote:
>
> > <big snip>
> >
> > > So you can get high performance (gain) IN SPITE OF high swr.
> >
> > this shouldn't be a surprise. but it sure bears repeating!
> >
> > Yes, George, What gives an antenna gain has NOTHING to
> > do with the impedance of the antenna. The impedance
> > relative to the impedance at the end of the amateurs
> > transmission line out the the antenna is from where
> > vswr comes. Gain comes from the geometry of the beast.
> >
> > 73, Jim, KH7M
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