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VOR whiskers antenna mounting

Stockmanreef

Well Known Member
do you think that it is OK to mount the VOR antenna under the horizontal stabilizer on the empennage skin on a 14-a or a tricycle in general? It would be nice to mount there because the kit already had a coax cable run to that point for ADS-B.

Just wondering since the tail of the plane is off the ground and could be a poking hazard.

thanks
ken
 
do you think that it is OK to mount the VOR antenna under the horizontal stabilizer on the empennage skin on a 14-a or a tricycle in general? It would be nice to mount there because the kit already had a coax cable run to that point for ADS-B.

Just wondering since the tail of the plane is off the ground and could be a poking hazard.

thanks
ken

Ken,

How about mounting the antenna here:


29368682048_84c832a2b6_k.jpg
[/url]fullsizeoutput_2f4 by Tom Valenzia, on Flickr[/IMG]
 
I have so much other stuff to get done, I thought that I would take the easy way out for once with this plane. I would not have to run more cable to the tail, don't have to take off the fairing, etc. Just need to make a doubler plate and install. Also, the puck won't completely fit in that spot, so it will stick out.

I am still debating that option. I do have enough cable to run it.

I do have a question about the existing coax cable. Can I put a male end on a short piece and to connect to the antenna or can I transition to regular wire and run about 6' of wire to the antenna. Will signal be compromised?

This way I can run a short cable to the transponder/ADS-B under the baggage are.

thanks
 
I've got mine mounted on the bottom of the tailcone under the HS and haven't had any "poking" issues in almost 4 years of flying. If I built another one I wouldn't hesitate to use that location again. Now that's for a tri-cycle, can't speak to a taildragger.

Here's an old pic (all I have access to at the moment).
FP10122014A00023.jpg
 
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I have so much other stuff to get done, I thought that I would take the easy way out for once with this plane. I would not have to run more cable to the tail, don't have to take off the fairing, etc. Just need to make a doubler plate and install. Also, the puck won't completely fit in that spot, so it will stick out.

I am still debating that option. I do have enough cable to run it.

I do have a question about the existing coax cable. Can I put a male end on a short piece and to connect to the antenna or can I transition to regular wire and run about 6' of wire to the antenna. Will signal be compromised?

This way I can run a short cable to the transponder/ADS-B under the baggage are.

thanks

If you choose to mount the antenna at the top, continue to use coax all the way up to the antenna.
 
I have so much other stuff to get done, I thought that I would take the easy way out for once with this plane. I would not have to run more cable to the tail, don't have to take off the fairing, etc. Just need to make a doubler plate and install. Also, the puck won't completely fit in that spot, so it will stick out.

I am still debating that option. I do have enough cable to run it.

I do have a question about the existing coax cable. Can I put a male end on a short piece and to connect to the antenna or can I transition to regular wire and run about 6' of wire to the antenna. Will signal be compromised?

This way I can run a short cable to the transponder/ADS-B under the baggage are.

thanks

Here you go:
https://www.amazon.com/Splice-Connectors-extending-cables-Compatible/dp/B00KRJMQVK

Typical loss at com/nav frequencies to do this would probably be around 1-2 dB; you'll never know it's there without hi-$ test gear.

Bigger risk is corrosion over time. If that concerns you (it wouldn't concern me, unless it's lying in the 'bilge'), you can just squirt the BNC connectors full of dielectric grease before connecting them.
https://www.amazon.com/Permatex-22058-Dielectric-Tune-Up-Grease/dp/B000AL8VD2/ref=asc_df_B000AL8VD2/?tag=hyprod-20&linkCode=df0&hvadid=312442771380&hvpos=1o1&hvnetw=g&hvrand=15442378917872986348&hvpone=&hvptwo=&hvqmt=&hvdev=c&hvdvcmdl=&hvlocint=&hvlocphy=9013892&hvtargid=pla-434092625191&psc=1

Or, you could listen to the next guy who tells you the wings will fall off if you try this...

Charlie
 
but at some point the BNC connector does have to transition over to regular wire to connect to the antenna. Correct? Or did I purchase the wrong one? My antenna just has two screws to attach wire to.
 
I was addressing the 'cable too short' issue. Terminating at the antenna would be in whatever manner the antenna mfgr recommends. There are tens of thousands of dipole antennas in service that use screw terminals to transition from coax to the antenna. Most will show the center conductor on one screw, and a short pigtail soldered to the shield and tied to the other terminal. Some will spec a 'balun' (impedance matching transformer); follow the mfgr's instructions. If you do that, it should 'just work'.
 
Have you bought your antenna? I have a RAMI AV-12L and it came with 25ft of cable with the appropriate connecters for the antenna on one end. As I mounted mine on the tailcone I didn't have to splice it at all. It's just one continuous run from the antenna to my splitter mounted on the instrument sub-panel.
 
do you think that it is OK to mount the VOR antenna under the horizontal stabilizer on the empennage skin on a 14-a or a tricycle in general? It would be nice to mount there because the kit already had a coax cable run to that point for ADS-B.

Just wondering since the tail of the plane is off the ground and could be a poking hazard.

thanks
ken

It is a poking hazard. Just think of your plane parked on the ramp and a kid runs under the tail, your plane is in the hangar and your dog runs into it or you drop something and get it right in the eye when you forget and bend over to pick it up.

A wingtip VOR antenna will do everything you need - and is the only VOR antennas I use on RVs.

I do have two bent comm antennas on the belly of my RVs, but they all get a piece of hose on them with a red flag anytime the plane is parked. They have saved my eyeballs on more than one ?clean the belly? efforts.

Carl
 
VOR/ ILS antenna

+1 on it being a serious eye poking hazard. Having seen a situation where someone almost lost an eye to a similar projecting wire (it went down between his eyelid and eye - still resulted in serious injury but ended with a full recovery) I would say -don?t try to save $200.00 on a $150K airplane to do a cheap crappy looking job that probably doesnt work that well anyway and creates a serious injury risk for anyone getting under the horizontal surface.
The VOR/ ILS signals are all horizontally polarized so putting the antenna close under the horizontal surface will at best change the antenna match and radiation patterns.

KT
 
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