hi Jeff,
I wouldn't attempt to tune the radials exactly to resonance, because that
will be most difficult to achieve due to a number of reasons... the worst
that may happen is that just one radial is exactly resonant, as it will take
(almost) all the return current and diminish the effect of (horizontal)
cancellation... make them all a little longer (or shorter) and tune the
radiator for resonance...
good luck
Uli, DJ2YA
----- Original Message -----
From: "Jeff Blaine" <jeff@ac0c.com>
To: <topband@contesting.com>
Sent: Friday, March 29, 2013 6:56 PM
Subject: Topband: trimming elevated radials
What is the preferred method of tuning elevated radials for uniformity?
I realize you can measure the lengths, try to get uniform heights, etc so
that you match the model as close as possible. However, it seems that
this is good only to the first approximation.
There are two methods that I thought of. Measuring the current at the
base of the vertical/radial union and trimming lengths iteratively trying
to get a uniform current reading on all elements.
The second one was to disconnect all the radials. And then connect them
one-by-one, trimming for the same resonance point for the single
radial+vertical as a pair.
73/jeff/ac0c
www.ac0c.com
alpha-charlie-zero-charlie
All good topband ops know fine whiskey is a daylight beverage.
_________________
Topband Reflector
All good topband ops know fine whiskey is a daylight beverage.
_________________
Topband Reflector
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