Generally the relative level of electric field of the vertical
component is given by cosine of the angle of the radiator
relative to zenith. Thus for a 5 degree angle, the loss
in the power pattern of the vertical polarized component
will be:
Atten = 20*log[cos(5)] = -.03 dB
for 15 degrees slant we get:
Atten = 20*log[cos(15)] = -0.3dB
At 45 degrees the theoretical loss is -3dB, but there may
be some additional loss due to the changes in antenna
efficiency as the radiation resistance of the antenna is
effected by proximity of the wire to the ground.
In short, as long as the antenna is mostly vertical, you won't
see much effect.
73 de Mike, W4EF.....................................................
----- Original Message -----
From: "Bill Gillenwater" <k3sv@pa.net>
To: <towertalk@contesting.com>
Sent: Wednesday, March 05, 2003 8:35 AM
Subject: [TowerTalk] Speaking of Vertical
The "how vertical is vertical" question raises another question. If I put up
a wire vertical, how vertical does it have to be? In-other-words, I have a
tree that is 50 feet high, or even 60 feet high, how much can I "lean" the
vertical wire and get the same results as a "true" vertical wire??
73 Bill
_______________________________________________
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Weather Stations", and lot's more. Call Toll Free, 1-800-333-9041 with any
questions and ask for Sherman, W2FLA.
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