Years ago I tried a a weather balloon filled with hydrogen from a hired
canister. The balloon's spherical shape made it highly susceptible to being
disturbed by even a fairly mild breeze. In my case the vertical wire was
tilted well away from being vertical. Fairly soon the balloon met the branch
of what was a pretty distant tree. Pop! Down came the wire and the ARRL
Topband contest which had just begun was finished (quite respectably, I should
add) with a center-fed dipole.
Now, years later, with a bit of experience in kite flying, a not-so-distant
public park with lots of open space and being a dedicated QRPer, I'm tempted to
try something larger than my 26m vertical + 21m horizontal wire over a 2.5 km
field of in-ground radials. My thoughts are centered on a kite-supported 7/8
wavelength vertical, the 4/8 wavelength bottom section base fed through an LC
tank circuit, decoupled from the top 3/8 wavelength section by just a capacitor.
72 (QRP-speak for 73),
Charles, W2SH
________________________________
From: Topband <topband-bounces@contesting.com> on behalf of Roger Kennedy
<roger@wessexproductions.co.uk>
Sent: Sunday, February 18, 2018 5:54 PM
To: topband@contesting.com
Subject: Topband: 1/2 wave inv L
Many years ago, a friend of mine used to operate on 160m with vertical
antennas suspended on a big Weather Balloon filled with hydrogen . . .
After using Quarter-wave verticals for a few months, he changed over to
Half-wave verticals . . . he found they worked much better !
He didn't have much of a radial system (due to lack of space), mainly just
earth rods at the base . . . so I suspect that's one of the reasons why.
Roger G3YRO
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