>The G5RV presents a highly reactive load on almost every amateur band and
>therefore a mismatch almost everywhere.
Yep. That's what I've seen! It looks decent on 40M but reactive
elsewhere. VSWR is about 2.5 or 3:1 which isn't too bad......
>It was never the intent of the
>designer to provide an antenna that provided a match on any band; his
>intent was to provide an antenna that could simply be reasonably used on
>lots of bands. Less than optimum efficiency from a G5RV is normal.
So I've learned. I've heard lots of people say that it's an all band
antenna and that you don't need a tuner. It might be usable on all
bands, but I've learned it's a compromise antenna. You sacrifice optimum
performance for being able to use it everywhere.
> Your
>vertical will be efficent if you have a ton of radials under it to minimize
>ground loss, and if the electrical length is sufficient tp present a
>resistive load ( with little reactance), somewhere close to 36 ohms for a
>quarter wave. As the design departs from these ideals, efficiency goes to
>hell.
Well, I don't have a ton of radials. And I don't need to either. The
vertical is elevated above ground by about 15 feet and the radials are
all in free space, so I don't have any ground loss.
Anyhow, efficiency of the antenna is not related to the power I see on
the power meter or how much power the amp will deliver or the amp's
efficiency is it?
I still haven't seen an answer to the question of why I get better PA
efficiency with the beam than I do with the other two antennas.
As for the power numbers, yes that makes sense. Some of the power
reflected at the antenna comes back down and re-reflects from the source
up the transmission line. So yes, the meter would read this twice.
Makes good sense. Seems like I now vaguely remember hearing this many
years ago.
Thanks for the help.
73,
Jon
KE9NA
--------------------------------------------------------------------------
The Second Amendment is NOT about duck hunting!
Jon Ogden
jono@enteract.com
www.qsl.net/ke9na
"A life lived in fear is a life half lived."
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