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My Inverted V's PLASTIC COATING has all peeled off. Is this a problem?

Jun 19th, 12:23

K6PAA

Joined: Apr 4th 1998, 00:00
Total Topics: 0
Total Posts: 0
I have an 80-40-20 Inverted V antenna that has been mounted in my backyard in Southern California (ie VERY HOT AND SUNNY) for several years, and the plastic covering has largely pealed off.

My questions are:
1) Should the antenna still function OK?
2) If the antenna is touching a branch, or leaves, is that worse for the antenna with the peeled-off plastic coating, or for an antenna with the original plastic coating still in place?
With NO plastic coating, can electricity leak directly from the antenna to the branch and/or leaves?
OR- Does it not make much difference?

OR- Should I get another antenna with the plastic intact?

Any thoughts appreciated!

Peter A K6PAA
Jun 19th, 14:01

AI4BJ

Joined: Sep 2nd 2003, 12:14
Total Topics: 0
Total Posts: 0
The wire insulation is only an insulator at DC. It is essentially invisible at RF frequencies. It would make for a pretty lousy antenna if that were not the case! :-)

Bottom line: You should not see a discernible change in performance.

73,
Mark AI4BJ
Jun 20th, 07:41

W1VT

Joined: Apr 4th 1998, 00:00
Total Topics: 0
Total Posts: 0
It is best if the antenna not touch live branches or leaves with or without the plastic coating. You still have capacitive coupling through the insulation. The effect is small near current nodes but large near voltage nodes. The high voltage at the ends of the antenna can create safety issues if you run high power. Best to use insulators and make sure that the ends of the antenna are clear of foliage. I would add another insulator to allow bending the ends down if there isn't enough room to be clear of foliage.

Insulation typically drops the resonant frequency of a dipole by a few percent. I would not replace an antenna if the insulation came off, but merely retune it if the frequency shift was an issue.

Zak Lau W1VT
ARRL Senior Lab Engineer
Jun 21st, 12:30

K6PAA

Joined: Apr 4th 1998, 00:00
Total Topics: 0
Total Posts: 0
Hi Mark and Zak-
Many thanks for your responses! Very helpful!
(Plus--- I get to save a few bucks by not buying a new antenna!!)
73, Peter K6PAA

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