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ADSB receiver location question

Yank

Active Member
I assume the ADSB receiver is located in the aft section of the tail (based on the wiring harness I installed that came with the tail kit). Any opinions on if this is a good location. I’m worried about moisture getting into this area.
 
Do you mean Antenna? If so, yes, on the belly toward the aft end of the aircraft.

Have a look at the Delta Pop Ultra Low Drag version...it's quite nice.

http://www.deltapopaviation.com/Ultra_Low_Drag_Transponder_Antenna.html

Works across the 1GHz band with very low VSWR (UAT @ 978 MHZ, 1040MHz, 1090MHz)

You can always run a bead of clear RTV (Silicone) around the base if you're worried about water incursion.
 
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I assume the ADSB receiver is located in the aft section of the tail (based on the wiring harness I installed that came with the tail kit). Any opinions on if this is a good location. I’m worried about moisture getting into this area.

I put my ADSB receiver behind the panel and its antenna is mounted under the baggage compartment. The antenna location in the tail, under the vertical stab. was for when ADSB and transponders were separate boxes - they are combined in newer avionics and, at least Garmin says to mount the antenna closer than at the tail. In that case, you won’t need the coax that goes all the way to the tail.
 
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I put my ADSB receiver behind the panel and its antenna is mounted under the baggage compartment. The antenna location in the tail, under the vertical stab. was for when ADSB and transponders were separate boxes - they are combined in newer avionics and, at least Garmin says to mount the antenna closer than at the tail. In that case, you won’t need the coax that goes all the way to the tail.


Thanks, now I need to figure out how to cover the hole where the antenna was supposed to mount... will need to hit up my multiple RV build neighbor for help....
 
Ooops...

I'll admit a mistake...

The antenna location in the tail of the RV-14 in F-01479 is for a UAT device (978MHz).

If you are planning on a Garmin GTX 330ES, 23ES, 345(D), 45R, GNX 375, etc. or similar unit that combines Transponder + 1090ES, ADS-B/In & Out, you should use the location as drawn on page 26-11, Figure 1 - also on page 26-14, Figure 1, for the antenna.

The dB loss/attenuation incurred by RG-400 at 1090MHz is about 18dB/100ft (varies a little with manufacturer...) GTX 330 has a limit of 1.5dB max loss and GTX 345 has a limit of 2dB max loss which means you are limited to < ~9Ft of RG-400.

Now I get to patch some holes and remove a chunk of RG-400, c'est la vie...
 
I'll admit a mistake...

The antenna location in the tail of the RV-14 in F-01479 is for a UAT device (978MHz).

If you are planning on a Garmin GTX 330ES, 23ES, 345(D), 45R, GNX 375, etc. or similar unit that combines Transponder + 1090ES, ADS-B/In & Out, you should use the location as drawn on page 26-11, Figure 1 - also on page 26-14, Figure 1, for the antenna.

The dB loss/attenuation incurred by RG-400 at 1090MHz is about 18dB/100ft (varies a little with manufacturer...) GTX 330 has a limit of 1.5dB max loss and GTX 345 has a limit of 2dB max loss which means you are limited to < ~9Ft of RG-400.

Now I get to patch some holes and remove a chunk of RG-400, c'est la vie...

Really good info -- filed away for my (still some weeks away) aft fuse construction.
 
Thanks, now I need to figure out how to cover the hole where the antenna was supposed to mount... will need to hit up my multiple RV build neighbor for help....

I just put a $25 “twig” antenna in the aftmost hole. Looks like it belongs and might keep the bugs out. :rolleyes:
 
I'll admit a mistake...

The antenna location in the tail of the RV-14 in F-01479 is for a UAT device (978MHz).

If you are planning on a Garmin GTX 330ES, 23ES, 345(D), 45R, GNX 375, etc. or similar unit that combines Transponder + 1090ES, ADS-B/In & Out, you should use the location as drawn on page 26-11, Figure 1 - also on page 26-14, Figure 1, for the antenna.

The dB loss/attenuation incurred by RG-400 at 1090MHz is about 18dB/100ft (varies a little with manufacturer...) GTX 330 has a limit of 1.5dB max loss and GTX 345 has a limit of 2dB max loss which means you are limited to < ~9Ft of RG-400.

Now I get to patch some holes and remove a chunk of RG-400, c'est la vie...

I'm working on this section right now. I'll be installing a Garmin GNX-375 so it appears I don't need this furthest aft antenna location. I've final drilled the #12 holes in F-01479 but I didn't final drill the larger 9/16" hole. I think I'll put an LP4-3 rivet in the center #30 hole but what would I use to patch the #12 holes?

This is the area I'm referring to:
 

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Modern Garmin transponders use the blade transponder antenna for ADS-B in and out, so no need for that little stubby thing in the tail. Check your chosen avionics install manual to verify.
 
Patch

I'm working on this section right now. I'll be installing a Garmin GNX-375 so it appears I don't need this furthest aft antenna location. I've final drilled the #12 holes in F-01479 but I didn't final drill the larger 9/16" hole. What did you use to patch the holes?

This is the area I'm referring to:

Pictures Pictures Pictures...

It's overkill...
 

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I mount the Dynon ADS-b receiver perhaps a foot away from the antenna, in the tail. This provides for minimal coax loss.

I make a simple U shaped mount out of 0.032” aluminum, the legs get some Proseal as adhesive to the inside of the tail bottom skin. The mount has nutplates for screws to attached the ADS-b receiver.

The receiver is connected to the SkyView system via a single, four #24 conductor shielded wire.

Carl
 
The dB loss/attenuation incurred by RG-400 at 1090MHz is about 18dB/100ft (varies a little with manufacturer...) GTX 330 has a limit of 1.5dB max loss and GTX 345 has a limit of 2dB max loss which means you are limited to < ~9Ft of RG-400.
+1 on Brian's comment; shorter is better for the transponder coax run, as long as you have the minimum required length (3 ft for the GTX-45R).

I'm not familiar with the Vans-defined antenna locations on the -14, but putting the antenna close to the center of the airframe will improve its tx/rx pattern somewhat. Does it make a huge difference? Probably not, but it's something to consider.

HTH

ds
 
Pictures Pictures Pictures...

It's overkill...

Thats a great solution to cover the middle 9/16" hole. But, what would you do if the middle hole hadn't been final drilled yet and was still #30? I could put an LP-4 in the #30 hole but what about the #12 holes? Are there pulled rivets that will fit in those holes? I've looked but so far haven't been able to figure out what size rivets those would be. Sorry, new builder here...
 
Thats a great solution to cover the middle 9/16" hole. But, what would you do if the middle hole hadn't been final drilled yet and was still #30? I could put an LP-4 in the #30 hole but what about the #12 holes? Are there pulled rivets that will fit in those holes? I've looked but so far haven't been able to figure out what size rivets those would be. Sorry, new builder here...

I would drill them all up to #12, use #10-32 3/8 truss-head screw on the outside and AN960-10 washer, AN365-10 nut on the inside.

Thinking down the road a bit, we were going to repurpose this hole for a camera mount location for either a GoPro or Natika Backup Camera for those under body video shots...
 
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