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Author Topic: Antenna coverage comparison  (Read 16696 times)

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NF2G

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Antenna coverage comparison
« on: March 17, 2010, 08:50:22 PM »
The RadarBox documentation advises against long coax feeds to rooftop antennas due to likely signal loss in the cable (unless you use hardline).  I compiled a polar plot map with the supplied magnet mount antenna sitting on top of a curtain rod in my 1-storey house.  Then I connected the RadarBox to my multicoupler, which is fed by a discone at 30 feet above ground level using about 70 feet of Belden 9913 cable.  (The antenna is at the far end of the house.)

The upper screen shot shows the polar plot for the original antenna.  The lower shot is the plot for the discone on the tower.  While there was some improvement in coverage in a couple of directions, the overall effect is not large.  This is probably because of coaxial cable losses.


NF2G

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Re: Antenna coverage comparison
« Reply #1 on: March 22, 2010, 03:14:46 PM »
The rooftop antenna didn't make much difference due to cable losses, but changing windows was another story.

The previous polar map was made with the supplied antenna on the curtain rod over my south-facing window.  The one below is with the antenna over my east-facing window - much worse!

« Last Edit: March 22, 2010, 03:19:35 PM by NF2G »

CZUL

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Re: Antenna coverage comparison
« Reply #2 on: July 01, 2010, 06:22:28 PM »
Hi

I currently have my RB antenna ( supplied SBS-1 antenna) about 60ft up. Cable run is quite long almost 90ft. Reception is fantastic. I see you are near Albany. I'm the Montreal feeder. I see your coverage over network. Looks really good from here.

CZUL

naird

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Re: Antenna coverage comparison
« Reply #3 on: July 03, 2010, 12:13:36 AM »
Great job CYUL  nice coverage paul. NF2G I'll send a screen shot from Kingston, I enjoy your coverage.



Neil


naird

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Re: Antenna coverage comparison
« Reply #4 on: July 03, 2010, 12:15:25 AM »
here's the screen shot

[attachment deleted by admin]

viking9

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Re: Antenna coverage comparison
« Reply #5 on: July 03, 2010, 07:18:57 AM »
Then I connected the RadarBox to my multicoupler, which is fed by a discone at 30 feet above ground level using about 70 feet of Belden 9913 cable.  (The antenna is at the far end of the house.)

I aasume your discone has a wide frequency range. An antenna cut for 1090MHz is necessary for max range.

Tom




Tom
Bury St Edmunds, Suffolk UK
15 miles SE of EGUN
32 miles SE of MAM > DIKAS track
http://www.viking9.co.uk

pure3000

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Re: Antenna coverage comparison
« Reply #6 on: July 03, 2010, 10:31:55 AM »
just wondered, has anyone constructed a dipole for 1090mhz to see the results?