AirNav Systems Forum

AirNav RadarBox and RadarBox24.com => AirNav RadarBox Screenshots => Topic started by: juangelb on August 21, 2011, 01:11:33 AM

Title: SBGR - Brazil - Polar diagram
Post by: juangelb on August 21, 2011, 01:11:33 AM

SC showing range achieved using a homebrew antenna.
There is a lack of signals from 220° to 270° due to a building very near to antenna and 6 meters higer.

Title: Re: SBGR - Brazil - Polar diagram
Post by: daelight on August 21, 2011, 02:28:12 PM

Thats a great range... if you wouldn't mind sharing the secrets of this 'home-brew' ... :) 

Title: Re: SBGR - Brazil - Polar diagram
Post by: juangelb on August 21, 2011, 10:49:52 PM

Hi Daelight,

I make several of this antennaes based on this project :
http://www.nodomainname.co.uk/Omnicolinear/2-4collinear.htm

1- Recalculated for 1090 MHZ and de coax locally found
2- Mounted this one with 8 stacked dipoles.
3- A very short coax cable run (4 meters)
4- Clear line of sigth but the building at 220° to 270°

Indeed it is not needed a very high gain antenna unless You use a very long coax cable run.
The secrets are : 360° of clear line of sight and short cable run.
But this conditions are very seldom achieved, so in my case I needed to use a Ubox and leftit with RB in a sealed box on top of the building and then a 40 meters network cable run till the computer.
This is a remote station that  i use in conjunction with an ICOM IC-PCR1550 to tune VHF tower, ATC, etcs for streaming audio and video (RB screen cature) to my site http://www.maquinasvoadoras.com.br (http://www.maquinasvoadoras.com.br) Select RADAR and choose ono of tem.

Cheers.