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| | |-+  Does it matter how you mount a J-pole antenna? Vertical/horizontal/angle??
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Author Topic: Does it matter how you mount a J-pole antenna? Vertical/horizontal/angle??  (Read 8214 times)
commercialcobb
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« on: January 18, 2008, 07:22:02 PM »

I am going to use a J-pole antenna for my setup, I need to know if it makes any difference how its mounted??  Fixed vertical, horizontal, thrown into a tree??  Is there a certain direction it must pointed or aimed to receive better??  I just cant hide a Discone antenna at my apartment... Any tips?
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Now I got a school boy heart, a novelist eye
A stout sailor's legs and a license to fly,
I got a native tongue from way down south
It sits in the cheek of my coastal mouth....
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KSYR-pjr
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« Reply #1 on: January 19, 2008, 12:07:52 AM »

Vertical (straight up) and fixed to a mast or other stable mount, as high and as far away from computers or florescent lighting as possible.  Why?  Because the people who build these things and know more about radio waves than I do all mount them this way.  Smiley   When you think of it, though, radio waves peak and trough more or less perpendicular to a level plane so you would want the maximum surface area of the antenna meeting the wave (at least that is what I recall from two semesters of college physics - but this was back in the early 80s).

As far as in what direction, I was instructed here on this site to aim my j-pole antenna so that the lower arm is closest to the transmission towers of the frequency I want to receive, like so (cue cool ascii art) :

|
|
|  |                        <------  source of waves (broadcasting antenna/airport)
|  |
---
|
|
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Regards, Peter
ATC Feed:  Syracuse (KSYR), NY
KB6HLM
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« Reply #2 on: January 20, 2008, 02:22:37 AM »

Maybe I can help put it in a more simple way ?

Transmissions from (aircraft/ATC) are mostly vertical so therefore it would make more since to mount the antenna polarization as close to vertical as possible

More info on antenna polarization can be found here http://ham-shack.com/polarization.html
This would explain why it's important to have VHF/UHF antennas mounted in the right polarization


Good DX & 73s
Glenn Las Vegas, NV
« Last Edit: January 20, 2008, 07:25:53 PM by KB6HLM » Logged

KSYR-pjr
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« Reply #3 on: January 20, 2008, 08:56:31 AM »

Maybe I can help put it in a more simple way ?

Perhaps if I underlined more words it would have been a simple explanation?    grin  grin  grin

But seriously, thanks for the link.  Interesting reading, there.
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Regards, Peter
ATC Feed:  Syracuse (KSYR), NY
KB6HLM
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« Reply #4 on: January 20, 2008, 07:45:30 PM »

Maybe I can help put it in a more simple way ?

Perhaps if I underlined more words it would have been a simple explanation?    grin  grin  grin

But seriously, thanks for the link.  Interesting reading, there.

Sorry if you felt I was undermining your reply "I meant no harm" and was only trying to help with the understanding of antennas

I did not poke fun at your writing so why did you poke fun at mine ??

I did however remove all the underlines on the reply

Are you happy now?

Luke 6
37"Do not judge, and you will not be judged"


Good Day
Glenn Las Vegas, NV


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KSYR-pjr
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« Reply #5 on: January 20, 2008, 08:46:59 PM »

Sorry if you felt I was undermining your reply "I meant no harm" and was only trying to help with the understanding of antennas

I did not poke fun at your writing so why did you poke fun at mine ??

Wow.
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Regards, Peter
ATC Feed:  Syracuse (KSYR), NY
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