A friend had installed a tail position mounted type ADSB out beacon in not a biplane. At the same time he also installed a new comm radio and new LED bulbs in the position lights. When he turned on the position lights to power up the beacon, there was severe radio noise (even when the engine was not running) when he installed the wiring for the new comm radio he did not use shielded wire. All thoughts were that the new ADSB transmitter was causing the issue due to the non shielded wire on the audio wiring. Wrong, while doing due diligence check (removing power from the tail position light ADSB beacon) he removed the new LED position bulbs, no more noise. It appears that the LED style bulbs where putting out some kind of interference that made the radio unusable. Who would have thought, this is just a heads up for those who are installing the LED type nav light bulbs they may cause issues. Shielding the audio wiring may have fixed the issue, but removing the LED bulbs and going back to standard bulbs cured the issue.
FYI Phil
FYI Phil
