Planned to continue with wiring through the cockpit today and started out measuring and cutting 4 new brackets for the right (passenger) side and drilled AN3 bolt holes in them (for the adel clamps) and 2 rivet holes each. Before I match drilled the attachment rivet holes onto the fuselage uprights, I checked to see what size adel clamp I might need (the right side bundle is smaller than the left side). It was at this point I knew I needed to make a decision - where am I going to mount the transponder and ADS-B antennas?
Taking grounding plane size, proximity to each other, proximity to other antennas, antenna cable length (important for the transponder) and maintenance accessibility into account, I decided the transponder antenna will go up front just forwards of the passenger's left rudder pedal. The ADS-B antenna will be mounted somwhere below the passenger seat. With that decision behind me I shifted gears and decided to start installing the transponder antenna. I got as far as fabricating the antenna cable with a standard BNC connector on the antenna end and a TNC connector on the transponder end. The transponder end is installed - next up it's time to drill a hole in the cabin floor for the antenna.
TNC connector attached to the transponder antenna cable on Dynon's TNC fitting installation notes.
Transponder antenna cable attached to transponder - was a tight squeeze tightening that on!
"X" marks the spot for antenna placement just in front of passenger left rudder pedal.