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February 29th 04, 06:03 AM

(RHF) wrote in message . com...
(John) wrote in message . com...
(RHF) wrote in message . com...
JD,

The G5RV is a good Antenna and an Off-Shoot of the common Dipole.

ALL TRANSMITTING THEORY ASIDE:
* For SWLs think of the G5RV as a Dual Opposing Inverted "L" Antenna
with common mode vertical (dual element) Leg.
- Here the G5RV is more Omni-Directional.
* For SWLs some specific Frequencies the Top Arms of the G5RV
Antenna function like a Dipole that is 'cut' for that Band or Bands.
- Here the G5RV is very 'directional' Dipole.

Thanks for all the responses so far. Yeah, that "dual opposing
inverted L" seems to make a lot of sense. And it is low noise. As for
directional properties: I don't seem to notice any. Maybe I haven't
bothered to experiment enough; but I've noticed that I seem to receive
stations on a par with reception reports I've read here and other
places. As for the top arms being "cut" for certain bands; again,
maybe I haven't experienced all, but I seem to get all I can get on
any band just as everyone else does. Anyways, those are just my
observations. I have always been happy with the G5RV. Some day I'll
need to get a bit more motivated and stretch out a really long wire
and see what difference it makes at my location.

Again...thanks to all the replies received.

John

.

JOHN,

There is only way that you will be able to "KNOW For Sure" that
your current G5RV Antenna is Omni-Directional or very Directional
on various SW Bands.

Take the G5RV Antenna down; and re-mount the G5RV Antenna
perpendicular (90*) to it's former position.

Then try listening to your old good stations and next Scan the
SW Bands for new stations that you could not hear before.

IF - The old Stations are 'weaker' and you are hearing NEW
Stations: Then your G5RV is very Directional like a Dipole.

However - If the old Stations 'sound-the-same' and you can not
hear any New Stations: Then your G5RV is Omni-Directional.

iane ~ RHF

Will depend on the band quite a bit though. Will always be pretty
omnidirectional on the low bands, unless the antenna is real high in
wavelength for the band used. "1/2 wave or higher" Max gain will be
straight up for the usual heights involved.
The G5RV acts pretty much as an 1.5 wl dipole on 20m, and should show
broadside gain of 2-3 db over a 1/2 wave dipole. The maximum "clean"
broadside gain will be at about 12 mhz. "appx 5 dbi". This is where
the antenna is an extended double zepp. The pattern is X shaped on
20m, with less gain. On 21 mhz, you will see an X pattern with about
4.7 dbi in four directions. On 28 mhz, you have a six lobe pattern
with max gain in four "x" directions. "about 4.6 dbi". But even with
the lobes and gain, it's quite probable you wouldn't totally lose any
station when turning 90 degrees, due to ground effects, metal in the
area, etc, unless you found a fluke good null by chance. You could
peak a few up though, and probably find a few good nulls, if you could
rotate the antenna.
The G5RV will act the same as any other 102 ft dipole, assuming no
feedline radiation. "Which it shouldn't have". If I were to run a G5RV
for all bands, I'd feed it with ladder line the whole way to the
tuner. I'd dump the coax and choke. Just causes excess loss, and a
quite larger chance of imbalance. MK