View Full Version : Comm antenna distance from pilot? Becker flex antenna?
January 14th 13, 11:41 PM
Help,
Anyone have any good info on how far a comm antenna should be from the pilot?
My current antenna in mounted in the rudder, and the coaxial is cracked inside the rudder.
Trying to find another place to mount an antenna without going external and without cutting into the rudder.
This is in a Silent-IN, and there is carbon in the tail from about the back third of the wing all the way back.
The area around the pilot is glass, and also there is a possibility of mounting behind my seat back.
Considering using the Becker flexible antenna that appears to be made from coaxial. Anyone have any experience with this antenna?
Thanks
Kevin
92
Bob Kuykendall
January 15th 13, 09:17 PM
Full disclosure: The glider I designed also has the VHF com antenna in the rudder. It is a convenient place to put an effective and efficient quarter-wave dipole in a ship with an all-carbon fuselage.
I've tried using those small flexible antennas in a couple of all-metal gliders, and have been consistently underwhelmed with their performance. I'd suggest you explore options for fixing the existing antenna. If you can pinpoint the place where the coax meets the antenna, it could be that the surgery required might not be that invasive.
Thanks, Bob K.
Darryl Ramm
January 16th 13, 08:11 AM
On Monday, January 14, 2013 3:41:35 PM UTC-8, wrote:
> Help,
>
>
>
> Anyone have any good info on how far a comm antenna should be from the pilot?
>
>
>
> My current antenna in mounted in the rudder, and the coaxial is cracked inside the rudder.
>
>
>
> Trying to find another place to mount an antenna without going external and without cutting into the rudder.
>
>
>
> This is in a Silent-IN, and there is carbon in the tail from about the back third of the wing all the way back.
>
>
>
> The area around the pilot is glass, and also there is a possibility of mounting behind my seat back.
>
>
>
> Considering using the Becker flexible antenna that appears to be made from coaxial. Anyone have any experience with this antenna?
>
>
>
> Thanks
>
>
>
> Kevin
>
> 92
As Bob says, fix it properly. Other parts of the fuselage that will block emissions in some directions are not RF opaque. A decent glider shop should be able to help you here. The important thing is to make sure you really know the cable/antenna is bad before you start cutting. When you say rudder do you you mean vertical tail fin? If its a rudder hinge mount you (or your A&P) may be able to just take the rudder off to get access.
Darryl
January 16th 13, 10:16 AM
It is really in the rudder. Removed rudder and was able to free up some of the coaxial and put a connector past the place that was obviously bad, but still showing 2 ohms resistance. Not sure yet, may or may not have fixed my problem.
Kevin
92
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