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Old December 30th 08, 01:53 PM posted to rec.radio.shortwave
Dave[_18_] Dave[_18_] is offline
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First recorded activity by RadioBanter: Jun 2008
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Default 5/8 WL Antennas ?

John Smith wrote:
Dave wrote:
RHF wrote:

Dave here is a Picture of a . . .
5/8 WL Ground Plane Antenna


No it isn't.

http://users.belgacom.net/hamradio/s...calantenna.htm


"The "ringostar" based coil:
Is made out of 26 cm of 2,5mm installation wire. Remove the isolation
of the wire and tin with a soldering iron the entire wire. The coil is
1,2 turns and has a diameter of 5 cm. One side is connected to the
antenna and the other side to the boom."
.

Note "Installation Instructions" of 5/8 wave vs 1/4 wave antennas.
1/4 wave verticals require a proper ground plane (radials or sheet
metal) to approximate the other half of a center fed dipole. The 5/8
wave is already over a half-wave long; no plane required. The coax
shield needs a ground, the antenna doesn't.

http://www.diamondantenna.net/m285.html

http://www.diamondantenna.net/hf6fx.html


You can use the outer-braid of the coax, or a ground wire, as a
counterpoise, as your text indicates ... but, for proper operation, at
least in all my experience, a counterpoise IS necessary.

However, as is common, people claim poor antennas are more than
satisfactory, for them ...

Regards,
JS


A "counterpoise" is not a ground plane.

We all would like to drill a hole in the middle of the roof, but
sometimes we are forced to clamp to something. The 5/8 Wave works well
on a clamp, at least as well as the 1/4 Wave in the middle of the roof.

"...However, as is common, people claim poor antennas are more than
satisfactory, for them ..."

"Buckets of irony littered the lobby"