On Mon, 09 Jan 2006 15:50:20 GMT, Cecil Moore wrote:

Ricke wrote:
If SETUP right , There the best HF I've ever used.

Maybe the only one? :-) The G5RV, with tuner, is a pretty
good 80m, 40m, 20m, and 12m antenna. If the series section
is varied from 20 feet to 36 feet, it becomes a very good
all-HF-band antenna. With the addition of a parallel 1000pf
capacitor with the series section at 22 feet, on 75m my "G5RV"
has SWR of 1.3:1 and works as well as a 75m 1/2WL dipole.

Now that is one of those things about a G5RV, no two are alike.

What are the key factors that "define" a G5RV? The things that I
recall from Varney's article we

- 31m long dipole
- centre fed
- flat top / inverted V
- open wire section of half wave length on 20m, from his physical
description, Zo about 520 ohms, but IIRC he suggests Zo is not
critical
- undefined length of either coax of open wire line of undefined, but
low Zo (50 - 120 ohms though he seemed to think figure 8 flex has a
lower Zo than it probably does).
- balun or no balun at the coax to open wire line transition,
depending on his article, he changed his mind.

My question is how many of these characteristics can be dispensed
with, or varied significantly and still legitimately speak of it as a
G5RV?

I am watching the argument between those who swear by a G5RV and those
who swear at a G5RV and suspect that one of the reasons (and not the
only reason) is they are not talking about the same thing.

There is a tendency to call anything with a ~30m centre fed dipole a
G5RV, and yet that component's pattern is independent of everything
else (excluding feedline radiation) and its efficiency is quite good
independently of everything else. It is "everything" else that
contains the losses that result from the dipole's feedpoint load
impedance, and it is the "everything else" that makes or breaks the
antenna.

Owen
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