FWIW,
I still fly 72 Mhz, and after what you described, I would have sent the TX in for repair after #3 or outright replaced it. No way would I have continued to use it
I watched a guy put in three planes one day at the field I fly at, not only all on the same TX, BUT THE SAME RX! 1st one was his fault, lost it in the sun. First flight of a new plane too. The rest? The infamous "I don't got it..." syndrome.
Good luck!
Bill S.
PS: Im a fan of Futaba
