Second Com Antenna

[Doggitz]

Hi Everyone - great to see a bunch of you at the Oshkosh barbecue

I want to mount a second com antenna of the belly of my 7SS which is still precover. I plan to use this is a back up antenna for a handheld com radio if my main com fails. I plan to use a bent antenna to allow plenty of clearance in the bush.

I have looked through the forum and have not found any posts on this subject - perhaps I just missed them. Has anyone done this? I spoke with J McB this morning and he told me that there is an autopilot servo mounting plate available, but I intend to use that option for my autopilot.

Thought that I would query the group to see if anyone has done it or has any suggestions

Thanks

Fred

KF 7SS - Building
Rotax 915

[109JB]

For a backup you don't really even need an external antenna. I used a handheld with headset adapter and the rubber ducky antenna that came with the radio for many years without problems on my Sonerai. Recently had something happen to my external antenna and am now back to the rubber ducky. Works fine and on that airplane it is my primary and only radio.

[jiott]

I have seen guys install coax patch ports on the panel so you can easily patch in your handheld to the main comm antenna. Seems easier and simpler than a second antenna.

[alexM]

I have rigged two airplanes with a connector in the coax that would allow me to disconnect the com and plug the antenna into my handheld, even while flying. Works great. Far better than trying to use the rubber duck on the handset.

[napierm]

I have rigged two airplanes with a connector in the coax that would allow me to disconnect the com and plug the antenna into my handheld, even while flying. Works great. Far better than trying to use the rubber duck on the handset.
Just don't key the TX with the antenna disconnected. The BNC connector went open circuit on my 601HDS (I wasn't the builder) and it blew a soldered in fuse in the radio. The COM radio TX doesn't like all the power to be reflected back in.

[Birdseyeview]

Although this doesn't address your specific question, you mentioned going with a bent antenna to give yourself plenty of clearance while landing in the bush. If your plane isn't covered yet you might consider an internal antenna that isn't hanging out in the breeze at all for the ultimate in ground clearance. I installed a folded dipole in my tail that has worked great. Bought it at Aircraft Spruce for $118. There has been a few other internal antenna options discussion in past forum history.

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