Topband: 1/2 wave inv L

[Charles Moizeau]

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 at contesting.com> on behalf of Roger Kennedy <roger at wessexproductions.co.uk>
Sent: Sunday, February 18, 2018 5:54 PM
To: topband at 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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