antenna placement

[Skint]

I am in the process of installing my Dynons, SL40 and 327. However, I cannot see any instructions on antenna placement.
The aircraft is an RV7a. Any suggestions?

[alpinelakespilot2000]

You will find the basic locational requirements in the installation manuals that came with the avionics. From there you'll have to decide where you think the best place to locate them is. You can do any number of searches on the forums to see where others have located them. Good luck.

[Rick_A]

I have a 7A w/ 480, SL40, GTX327. I used a straight comm ant just behind the spar left of center for the 480, the SL40 uses a bent whip about 18" - 24" behind the baggage bulkhead left of center and the Xpder is just a few inches behind the baggage bulkhead right of center.

I get good range on both comm's.

[agough277]

For best results keep the coax short as possible. I placed the comm and transponder antennas under each landingear mounts forward of the wing spar. The skin there is thicker and does not need additional reinforcing.

[Camillo]

I heard that coax. lenght is not essential for COMM, since they "travel" on relatively long waves. Coax. lenght is essential for transponder and DME, since they go at around 1.000 Mhz.

Also, if you wish to have 2 COMMs, I will suggest one up and one down (so tower could not tell you any more you are "in the shadow" of one of your wings).

I did/am doing as follows:

- COMM1: straight RAMI over the turtledeck, immediately behind the skins joint (when you open the sliding canopy, it will almost touch the antenna);
- COMM2: whip RAMI under the belly (still have to decide final location: maybe just under the pilot seat; avoid major obstacles in the "line" of the antenna, as gear legs; install it in a square 12*12' or 16*16' - can't remember exactly - area; antenna will need it to achieve its correct wave lenght);
- VOR: in VS fiberglass: poles pointing forward;
- XNDR: between pilot pedals, under the belly, just beside the aluminium longeron (must be at least 3 feet from receiver...so pilot side);
- DME (still have to decide: maybe under the belly, baggage area, right side);
- ELT: behind COMM1, at least 2 feet from it (should be 3 but I have not enough space) (leave enough clearance from VS, because it will fold with speed);
- ADF: you will no longer use it: I'm planning to place antenna in the baggage area, left side;
- GPS: under the fiberglass cowl, left side.