Thanks for the suggestion.
When trying RTS, for what ever reason the DUO goes into transmit mode; as if the signals are reversed. I have the same problem with HRD when trying to use RTS as the PTT control. Fldigi works as it has a native TS-480 configuration in the Hamlib library and looks to be using CAT commands to control PTT.
So there is an issue with either RTS control in the DUO firmware or something strange in my system/configuration. No problems with my various Yaesu transceivers I have in operation so I lean towards the RTS control being broke.
Anyone els using RTS to control PTT on the DUO?
Thanks - Will - N7IPY