Author Topic: Recommended distance between PAW antennas  (Read 3288 times)

EuropaStephan

Recommended distance between PAW antennas
« on: May 22, 2017, 10:02:44 pm »
Hi

I have a few different options where to place my PAW antennas.
One of them is to place the antennas together with approximately 10-16 cm separation.

My question is if it's too close? Is there any recommended minimum distance between these antennas?

Thanks in advanced

Stephan

exfirepro

Re: Recommended distance between PAW antennas
« Reply #1 on: May 24, 2017, 10:19:48 am »
Stephan,

Have you read the antenna guide on the main website here...

http://www.pilotaware.com/wp-content/uploads/2016/10/PilotAware-Antennas.pdf

The generally accepted recommendation for minimum separation between antennas is 1/4 wavelength, however I (and others) have installed and run units successfully with both antennas mounted directly to the PAW unit itself.

The critical issue is the positioning of the P3i antenna, due to the low transmit power allowed for this band. It is essential that this antenna is mounted where it can get as good an all round view as possible to warn you of other P3i aircraft. The thinner 1090MHz antenna is 'receive only' and is listening for much stronger ADSB, Mode C and Mode S signals, so its placement is less critical, though optimising the position will always ensure best possible reception.

Hope this helps

Feel free to come back to me once you have read the Antenna document

Regards

Peter

Giver

Re: Recommended distance between PAW antennas
« Reply #2 on: May 24, 2017, 11:12:50 am »
Stephan

On my Europa i used the extended di- pole antenna on the back of the fuel inlet cobra,
It all composite and plastic in that area and pretty much the highest point in the aircraft without going outside,
admittedly i am still not flying at the moment( soon to be rectified 😀) but i have had good reception on aircraft from inside a metal roof workshop, and much better when outside doing engine runs ,

ivor

EuropaStephan

Re: Recommended distance between PAW antennas
« Reply #3 on: May 24, 2017, 11:51:56 am »
Peter and Ivor

Thanks for your explanation. I have read the antenna guide but missed or not understand that information.
My plan (version 1) is to mount both antennas high-ish in the windscreen.

Ivor: hope to you soon somewhere in Europe. This year we are heading for Mallorca, via San Sebastian. Perfect with the PAW installed.

Stephan