7A and 9A Owners, Transponder antennas Where to mount??

[flyvans.com]

COM1 bent whip below the righthand baggage compartment bay, close to the center tunnel. excellent functionality.

XPDR stub antenna just beside the fuel vent in the front right bottom skin. working great!

COM2 used elt antenna mounted to the inside/rear of the rollover bar on the righthand side. dismal performance. would look for alternative location next time. works ok for short range on ground / formation in the air. but e.g. very poorly for atis reception.

3 GPS antennas on the glareshield. working great.

FLARM short stub 2.4ghz antenna opposite to the COM2 on the lefthand inner side of the rollover bar. again appears to be a poor location, not getting as much reception as would be ideal. may rewire this one of these days.

so in general, stay away from the rollover bar / inside cabin other than the glareshield if possible.

[swisseagle]

Hi Bernie

Thanks for your input ;-) will do it like:

- The transponder in the lower right corner, beside the fuel vent.
- COM1 on top, rear fuselage.
- COM2 on bottom between fornt and rear spar.
- ELT behind roll over bar (not ideally, but in a flipped condition, there is hopefully still a "window to the sky".
- FLARM on glareshield.
- GPS: 1x on glareshield, 2x FWF.

[mcencula]

I spent some time with the Garmin manuals and selected locations that nearly meet all the requirements:
Transponder far aft in the tail, just forward of F-710 bulkhead.
ADSB just aft of the baggage bulkhead.
2x COM antennas just aft of the main spar, in between the outboard most seat ribs on either side.

My plane isn't flying yet, so I can't comment on performance.

More info here.

[ron sterba]

OK I checked on the coaxial cable called 400 something. Non burnable, are you ready for the price?????? $8 a foot,,, darn, I think I'll stay with the R 58, think thats the one that works just fine for all the antennas,

Ron in Oregon

[roee]

Originally Posted by ron sterba

Hi Guys, Well time has come to mount my 3 antennas, Transponder,ADS-b and com antenna on my RV9A. Using the Skyview 10" and Ads-b TRANSPONDER and one ICOM 210. LOOKING AT LOCATIONS YOU FINE FAVORABLE for these antennas.

Thanks
Ron in Oregon

A while back I did a little write-up on antenna placement. You can read it here:
http://www.kalinskyconsulting.com/rvproj/antennas.htm

Originally Posted by ron sterba

OK I checked on the coaxial cable called 400 something. Non burnable, are you ready for the price?????? $8 a foot,,, darn, I think I'll stay with the R 58, think thats the one that works just fine for all the antennas,

Ron in Oregon

RG-400 is superior to RG-58 in RF performance and flammability characteristics, and has long ago replaced RG-58 as the modern standard.

Not sure where you looked to find it at $8 / ft. I just checked the first two sources that came to mind, B&C and SteinAir, and they both sell it for under $3 / ft. Best price I've seen recently is from B&C at $2.35 / ft.

[Walt]

Originally Posted by flyvans.com

XPDR stub antenna just beside the fuel vent in the front right bottom skin. working great!

Xpdr needs a ground plane approx 8" dia (4" from the edge).

Originally Posted by mcencula

I spent some time with the Garmin manuals and selected locations that nearly meet all the requirements:
Transponder far aft in the tail, just forward of F-710 bulkhead.

Xpdr antenna should be kept as short as practical, 8' is the max with the garmin units (with RG400).

[larrynew]

I mounted the transponder and ads-b antennas just behind the 705 bulkhead/rear wing spar.



Both transponder and ads-b boxes are mounted under the baggage floor just a few inches from the antennas. My lower comm antenna is mounted just forward of the 707 bulkhead. Not flying yet but they work in my garage.

[ron sterba]

Nice job Larry! I hadn't thought of mounting the units in the floor but a real eye catcher. You got me thing'in know. Neat idea my friend.

Ron in Oregon