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-   -   Flexible ADSB/Transponder antenna (https://vansairforce.net/community/showthread.php?t=181835)

Planecrazy232 04-27-2020 02:28 PM

Flexible ADSB/Transponder antenna
 
My ADSB and Transponder both use the little TED antenna below. For some reason I like breaking these things when I'm under the plane. I'm up to two now. Is there a flexible version of this thing??


PhatRV 04-27-2020 02:51 PM

I haven't flown but I bought a low profile blade antenna for my RV8. I also thought the single pole model is too easy to break.

cfiidon 04-27-2020 03:15 PM

Blade
 
I also use a blade from Delta Pop Aviation, and thus just listed my monopole like yours for sale.

Don

lr172 04-27-2020 03:29 PM

I have broken a few. I solder them back on with silver solder and keep them in the plane as spares. They are not hard to disassemble for soldering. Just need a jig to hold the rod in place.

Larry

jliltd 04-27-2020 04:59 PM

On an aircraft that flies as fast as and RV the blade shaped antennas have a lot less drag than the ball and stick type. You wouldn't guess it by looking but the round profile (cylinder) has significantly more drag. Google it.

So why not upgrade to a blade type?

I have a few TED brand antennas and on my Aviat Husky the white nylon support keeps falling down the stem rather than staying in place. This might be another one of those you gets what you pays for situations. I still have about 10 each of the TED UAT and TXP antennas new in the baggie. I use them for slower airplanes. But understand the difference between a $25 antenna and a $100 antenna.

Jim

ReidVaitor 04-27-2020 07:39 PM

Ted antenna
 
I built a fiberglass shark fin and put the antenna inside it, looks like the expensive ones but it costs about $6 to build one
Create foam mold big enough to fit the antenna into, when you have the right size (Remove the antenna) cover it with micro balloon mixed with resin and lay a couple ply of fiberglass over it, sand it, get 3m double sided (15lb) tape and install over the antenna on plane.
Been working for years without an issue. Did it for both the ADSB and transponder antenna.

Scott Hersha 04-27-2020 07:47 PM

True.... But ?a lot less drag = about 1/4 KTAS on an antenna of this length. I?ve broken 2 of these antennas, one Delta Pop blade, and one of the rod/ball antennas.

I re-epoxied the DP antenna, and then just straightened the rod/ball unit. Both check out fine on the bench. The rod unit has been flying , after bending it back to straight, for 3 months, including a transponder recert/ADSB test, and it?s working fine so far. I?m sure my DP antenna would too.

Dirty air on your belly doesn?t pay the same penalty as something in smooth air. A rod antenna is definitely more ?draggy? than a blade, but is it worth 4X the cost? Especially if you think you may damage it cleaning the belly, maybe more than once? I still have my repaired DP blade if anyone wants to buy it. I?ll sell it to you for the cost of a six pack - your choice on brand.

If you are anal about cleaning your belly (99% of us are), you WILL damage a belly mount antenna eventually. You will need to repair or replace it.

Snowflake 04-28-2020 08:07 AM

I sense another part coming from Steve from his 3D printed parts factory... :) A shark-fin to fit over the stub antenna would be pretty easy to print.

Scott Hersha 04-28-2020 06:30 PM

I?m in if he does it. He?s a hangar neighbor, so I will be happy to Beta test it!

jliltd 04-29-2020 01:59 AM

Quote:

Originally Posted by Snowflake (Post 1425917)
I sense another part coming from Steve from his 3D printed parts factory... :) A shark-fin to fit over the stub antenna would be pretty easy to print.

That would be great if he did. I would encourage him to use the UAT tuned version vs the transponder tuned version. The UAT is ever so slightly longer due to the lower 978 frequency and it takes a keen side by side comparison to notice the difference. But it does exist. The 978 Mhz UAT length cover would be backwards compatible with the 1030 Mhz/1090 Mhz version.

Jim


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