TV antenna ground plane?
 

After reading the following paragraph, I'm wondering if my TV
antenna is affecting my Antron 99 either positively or negatively...

11. If you mount two or more antennas close to each other, you will
alter the transmission patterns of each one. The affect may be either
positive or negative. We recommend that a minimum of 12" exist between
your CB antenna and other types of antennas.

http://www.firestik.com/Tech_Docs/63Things.htm

Both are clamped directly to the same pipe/mast. The TV
antenna is clamped 12" below the bottom of the Antron, and the highest
point of the antenna is about 6" below the Antron.

Another thing that's got me wondering if it is affecting the
radiation pattern is that fifteen years ago, I didn't have the TV
antenna under the Antron, and the neighbors whined so much about
hearing me in their telephones that I put all my CB stuff in the
attic. Now, I've put the exact same equipment back up two weeks ago,
with the addition of the TV antenna, and I haven't had one complaint.
Could the TV antenna be affecting my radiation pattern?

Could be.. Most likely acting as a minimal ground plane, and elevating the
radiation angle a bit.

--
KC6ETE Dave's Engineering Page, www.dvanhorn.org
Microcontroller Consultant, specializing in Atmel AVR

Hello Glenn S:

As Dave has said it may be acting like a ground plane, to some extent.
And changing the elevation pattern. Or even helping decouple some of the
energy coming down the coax.

Also maybe the neighbors have cable TV now. Which is a big help.

Jay in the Mojave



Glenn S. wrote:

After reading the following paragraph, I'm wondering if my TV
antenna is affecting my Antron 99 either positively or negatively...

11. If you mount two or more antennas close to each other, you will
alter the transmission patterns of each one. The affect may be either
positive or negative. We recommend that a minimum of 12" exist between
your CB antenna and other types of antennas.

http://www.firestik.com/Tech_Docs/63Things.htm

Both are clamped directly to the same pipe/mast. The TV
antenna is clamped 12" below the bottom of the Antron, and the highest
point of the antenna is about 6" below the Antron.

Another thing that's got me wondering if it is affecting the
radiation pattern is that fifteen years ago, I didn't have the TV
antenna under the Antron, and the neighbors whined so much about
hearing me in their telephones that I put all my CB stuff in the
attic. Now, I've put the exact same equipment back up two weeks ago,
with the addition of the TV antenna, and I haven't had one complaint.
Could the TV antenna be affecting my radiation pattern?

You pose an interesting question.

One antenna (your transmitting/receiving antenna) is vertically
polarized; the tv antenna is horizontally polarized. Normally, a
ground plane is formed by wires running away from a vertical antenna -
or - a mesh of wire extending away from the antenna.

Since neither exist, I suspect you would have little coupling to the
tv antenna. The horizontal elements are so short that I doubt any
directly beneath the vertical would have an effect and the boom might
have a small effect, but only in the directions that it is running
beneath the vertical.

I'm not saying there is no effect; I am of the belief that any effect
would be exceedingly small (with a possible exception of a small
change in the radiation pattern in the direction (both ends) of the tv
antenna.

The best solution is to convince your wife that you need an 8 element
rotatable cross-polarized lightning deflector mounted on top of a 120
foot tower :))
(can we spell 'Yagi'?) LOL

(why do I see a number of the group planning to try and convince their
wives that they need a similar 'lightning deflector'?)



73 from Rochester, NY
Jim

My rule, keep as far away as posible...another suggestion...run as many
elements as you can afford, less watts you'll need to talk ..beams beams
beams

--
..



---
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From: (George=A0Kinzer)
My rule, keep as far away as posible...another suggestion...run as many
elements as you can afford, less watts you'll need to talk ..beams beams
beams
--
..
Great advice. Of course, if your house is located next to a large body
of water, sometimes you can sound like you are King of the hill

Twistedhed wrote:
From: (George Kinzer)
My rule, keep as far away as posible...another suggestion...run as many
elements as you can afford, less watts you'll need to talk ..beams beams
beams
--
.
Great advice. Of course, if your house is located next to a large body
of water, sometimes you can sound like you are King of the hill

let me guess twist you are talking about george ;)

From: (jim)
Twistedhed wrote:
From: (George Kinzer)
My rule, keep as far away as posible...another suggestion...run as many
elements as you can afford, less watts you'll need to talk ..beams beams
beams
--

Great advice. Of course, if your house is located next to a large body
of water, sometimes you can sound like you are King of the hill

let me guess twist you are talking about

george ;)
_
Geo runs an illegal linear on channel 6.