NWade wrote:More evidence that this is radiated signal: If I put a piece of 0.025” aluminum just in front of the antenna (blocking line of site to the EFIS display panel) and touching the turtledeck (so stray signal can drain to ground), the “incoming signal strength” on the COM display drops to 0.
Two things come to mind that I will pass on for your consideration.
1) I have my comm antenna mounted on the bottom of my taildragger just ahead of the main spar tunnel. I'm using a stainless steel whip and LMR-240 coax. My radio is a Flightline 760 and I use the MGL singles. On the belly my radio sends and receives extremely well. Got a "loud & clear" radio check the other day from pattern altitude from another pilot 45 miles away. Ground ops work well also with a belly mount antenna.
2) With that much RFI coming from that EFIS unit you should consider your own safety & health. I have no way of knowing how much or what frequency of radiation you are dealing with but it's getting into the antenna behind you so you will be getting a good dose of it yourself.
Dunno if this helps,
Dale Williams
N319WF @ 6J2
Myunn - "daughter of Cleanex"
120 HP - 3.0 Corvair
Tail Wheel - Center Stick
Signature Finish 2200 Paint Job
165.2 hours / Status - Flying
Member # 109 - Florida Sonex Association