[Mikey405]

Hi Ken.

Thank you for the interesting advice. I will try a selection of those things tomorrow.

One thing I had considered is using a separate RF earth for the Spitfire by driving a separate 1200mm copper earth rod into the ground near the aerial and using coax from the Spitfire to both. (My radios are all currently connected to the same "earth" (water pipes) as the RF signal from the transmitter at the moment which may not be helping matters.) I think the RF earth on the Spitfire is the same as the signal earth so I'd still have to isolate the power and the audio signal.

Thanks Ken.

Kind regards.

From Mike.