In article ,
RB wrote:

MFJ says the G5RV, when configured as a single wire fed horizontal antenna,
acts a Marconi type of top loaded vertical.

Specifically, the instructions give me two options for 160M use. One is to
feed one side of the coax at my shack with a single wire to the tuner, and
ground the other side of the coax to a good earth ground or counterpoise. I
have no idea what this becomes in this mode.

The other option is to connect the coax outer conductor to the inner one,
and feed both with a single wire from the tuner, using a good earth ground
or counterpoise to the rig.

A question is what the consensus is as to which of the above feeds would be
the better?

The second is the more commonly-recommended approach, I believe. As I
understand it, you end up with a vertical radiator (the coax braid),
top-loaded with a big capacity hat (the G5RV proper), working against
your counterpoise wire or radials (or against just a ground stake,
which probably won't give great results due to high ground losses).

I'm rather sceptical of the first approach. If your rig is properly
RF-grounded, this approach seems little different than trying to feed
the coax directly from your tuner, except that you'll have some length
of the ground-return current coming back to your rig via its grounding
strap/wire rather than inside the coax. You're going to be trying to
drive a short horizontal antenna (low radiation resistance, in series
with a high capacitive reactance) through coax... a recipe for a very
high SWR and high losses. You may be able to get it to tune up, if
your external transmatch is a capable one, but your on-the-air
efficiency is likely to suffer badly.

If your rig isn't RF-grounded, you've got other problems with the
first arrangement :-(

--
Dave Platt AE6EO
Hosting the Jade Warrior home page: http://www.radagast.org/jade-warrior
I do _not_ wish to receive unsolicited commercial email, and I will
boycott any company which has the gall to send me such ads!