Dual Comm Antenna Placement

[pvalovich]

I've checked the archives and have gotten conflicting info.

-8A with an SL30 and ICOM for dual comm. 2 Comant bent whip antennas on the bottom aft of the wing staggered so the aft antenna mount is slightly aft of the end of the foward antenna tip, but on opposite sides of the fuselage.

My buddy has raised the question of whether such placement is too close and transmitting on one radio will fry the other. Other posters have said "no problem". What is truth?

****, it's always something.

[Jim P]

Paul,

I have a Garmin 480 and SL-30, each with seperate COM antennas. They are Comant bent whips, located about 1.5' aft of my main spar, and about 3' apart on my RV-7. Both COMs work great.

[vmirv8bldr]

Paul, I've been struggling with this myself. (Planning for a 430/sl40)combination. I've seen an -8 with the comms on the inboard-most inspection panel of each wing. But, there are some concerns about proper grounding, etc. I have not done so yet, but am contemplting putting them on the wings to get the 3' spacing suggested. (On the wings a la bent whips, NOT IN the things a la Bob Archer style.)

Still mentally debating this.

Whatever locations I choose, they will be at least 3' apart as per manufacturer's recommendations, 'cause if something breaks.....

[tomagin]

I'm still mulling it over but had the same concern about separation on an -8. I have been considering putting the two bent whip antennas on the first inspection plates outboard on each wing. Seems like an easy place to install, remove if necessary and wire ---- with separation of more than 6ft.

On the same subject I have the Bob Archer VOR/LOC/GS in the right wingtip and the Bob Archer MB antenna in the left wingtip. My Comms are a 430W and Becker 4201. The TXP will be close to the center of the fuselage but avoiding the pushrod just aft of the rear seat.

[AX-O]

Here is another question related to this issue. If you have an antenna foward of the second antenna, how do you messure the distance. Is it from the front of the foward antenna to the front of the aft antenna? or is it from the rear of the foward antenna to the front of the aft antenna?