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Old September 5th 08, 12:52 PM posted to rec.radio.amateur.antenna
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First recorded activity by RadioBanter: Sep 2008
Posts: 14
Default r7 vertical resonates too high

Those 5 spokes are a 'capacity hat' loading the bottom half of the 'dipole'.

If the problem is on ONE BAND, I would look at the capacitor assy for that
particular band. They are usually the first item to fail. Your R7 has been
on borrowed time for a few years.

Emil
W9NM

"Edmund H. Ramm" wrote in message
...
In "Ed Cregger"
writes:


[...]
The R7 doesn't use radials or a counterpoise.


Yes it does, those 5 spokes are the counterpoise.

It is the electrical equivalent of a 1/2 wave antenna on all bands.


Lambda 3/8.

[...]


Like the OP, I tend to agree that the problem is in the black box.
There were several articles published on how to restore the black box to
original specs. Anyone know of their location?


http://www.iol.ie/~bravo/r7_vertical.htm

73, Eddi ._._.
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