Avionics: Antennas mounted.

You can read about the antennas I'm using for my aircraft.

Per the EAA Hints for Homebuilders, I used DAP Alex Plus latex caulking to seal the antennas to the airframe.  It is a "siliconized latex" so it's paintable.  Here is an example of the bead of caulking placed along the perimeter of an antenna prior to bolting it on.  It dries clear and can be peeled away from unprepped surfaces.

This image shows the two comm antennas and one UAT 978 MHz antenna for the SkyRadar DX ADS-B in.

Here is the underside of the GA-35 GPS/WAAS antenna for the GTN-650 GPS/Nav/Comm.  The left image shows the routing of the coax.  I chose not to rivet in the doubler plate I constructed (center).  The side facing the top skin is not primed and primer was removed on the skin around the bolt holes to ensure a good ground connection.  More information on how I mounted this antenna can be found here.

Coax leading to the right and left comm antennas (top) as well as the SkyRadar DX UAT and GTX-330 ES 1090 MHz transponder antenna (bottom).  I plan to fabricate and add a doubler to the UAT antenna.  Although it's close to a rib, that skin is 0.025" and the blade can create significant torquing when slipping/skidding.

The GTX-330 ES 1090 MHz antenna.

The 1090 MHz ADS-B in antenna for the SkyRadar DX has not yet been installed.  I'm still deciding on where to place that antenna.  And the same for the Comant CI-158C-2 VOR/LOC/GS antenna for the GTN 650.