[NSRCA-discussion] Trainer box frequency interference

[J N Hiller]

Question for Tony
I have herd of a transmitter being used as a trainer box transmitting a
signal while turned off. Today I witnessed the condition. While starting my
airplane a club member was preparing to fly with a buddy box. The non
primary transmitter (buddy box) was on my frequency and caused interference
even though it was turned off, luckily I hadn't gotten started yet and
noticed the interference. As a test we pulled the crystal from the buddy box
TX being used which stopped the interference.
The primary TX was on another frequency and the buddy box TX was on my
frequency but of a different brand than their primary TX.
If you would please explain how this is possible it may save someone's
airplane and possibly some hard feelings. I the future the club members will
just get both frequency clips, but how many more are out there. We were
lucky today.
I was about to upgrade to 2.4 but the dentist the $$ yesterday.
Thanks
Jim Hiller
Spokane WA.