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Old September 17th 06, 10:07 AM posted to rec.radio.amateur.antenna
J. Kragh J. Kragh is offline
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First recorded activity by RadioBanter: Sep 2006
Posts: 2
Default Endfeed vertical halfvawe antenna

Good morning all

I take the opportunity to answer all of you at once.

Thank you for a lot of suggestions. I had thought about the J-pole the
problem however the problem is that we have some glass fibre tubes only
about 25 mm in diameter, so we are somewhat constrained with respect to
realise a J-pole.

Regarding a groundplane as suggested by some, the idea is to mount the
antenna on top of a mast much like an ordinary 2 meter or 70 cm vertical
antenna. In these circumstances a ground plane is not feasible.

Tom Ring asked about 6 metres in Europe. In some counties among them Denmark
there are few FM repeaters in operation. A number of amateurs have either
old army radios or modified Land Mobile Radios (LMR), typically salvaged
from taxis, fire engines and so on. All these radios operate in FM. Our idea
was to operate in this segment of 6 meter operation, not to operate in the
DX part of the band. Together with som fellow amateurs we have also tried 6
metre mobile. It actually works!

vy 73 and once again thanks for the responses

Joergen, OZ7TA
"J. Kragh" skrev i en meddelelse
k...
Togethere wih a fellow amateur I am trying to design an endfeed halfvawe
vertical antenna for 50 MHz.

We have encountered som problems regarding the impedance match in the
feedpoint. I have surveyed the ARRL Antenna Book and Antennebuch (a
German antenna book very popular in Europe). The properties of the antenna
and its impedance is well understood. The missing point is how to realise
the matching network

In order to avoid reinventing the whee: Does anybody have some good links
to study practical realisations of the matching network?

vy 73

Joergen, OZ7TA