I flew mine quite happily on PPM BUT had to route the aerial from the fueslage mid nose to the wingtip to get good range.

IMHO your problem is running your aerail along the fuz. The ECU - PUMP - TURBINE are all electronically noisy. Get your aerial well away from them. THEN DO A RANGE CHECK WITH THE TURBINE RUNNING. Trial and error until you get good range.

P.S. I use a 500mm whip now on Jets.