W8JI's on the air tests were done on 80m where I believe the G5RV is
basically omnidirectional. On higher frequencies the antenna has some deep
nulls which could greatly affect the signal strength.
John KK9A
Re: [TowerTalk] G5RV vs 40M dipole
from [Steve Hunt] [Permanent Link][Original]
Subject: Re: [TowerTalk] G5RV vs 40M dipole
From: Steve Hunt <steve@karinya.net>
Date: Sun, 26 Apr 2015 18:58:16 +0100
If you use a G5RV, the simplest way to get improved signal strength reports
is to announce that you are using something else ;)
This from W8JI:
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On The Air Testing
One of the only ways to reliably test an HF antenna is a blind A-B
comparison against another known good reference antenna. Since I also had a
dipole at 100 feet a few hundred feet away from the G5RV (similar height), I
had an ideal testing situation.
Blind Test
I checked into various groups on 75 meters and did a blind A B antenna test.
I would say "this is antenna one one one, this is antenna two two two" while
switching antennas. The results were:
1. Nearly ALL of the reports indicated NO difference in signals! (58
equal reports)
2. When a difference in signal was reported, about equally split either
the full size dipole or G5RV would win. (7 G5RV better, 9 dipole
better)
Announced Tests
I also did tests that called the antennas by name. I would say "This is the
the G5RV,G5RV, G5RV. This is the dipole, dipole, dipole". The results were
rather revealing.
1. When I would call each antenna by the correct name, the G5RV was
reported "weaker" or with "poorer audio" or some other negative
comment more than 80% of the time. The remaining stations reported
no difference!
2. When I would call each antenna by the /*opposite name*/, the antenna
I was calling the G5RV was /*still reported*/ in some negative
context about 80% of the time. The remaining percentage again
reported no real difference.
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Full story on Tom's web site:
http://www.w8ji.com/g5rv_facts.htm
Steve G3TXQ
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