Hello, I have an Icom AH-4 automatic antenna tuner. It has an output to key the transeiver PTT during the tuning process. Is there a pin in the QDX processor, configured in the program I can use to activate the TX from the tuner?
Thanks,
Sergio.

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(Automatic) Antenna tuners can destroy QDX finals withing milliseconds, see recent discussions in this newsgroup.?

I know that finals can be destroyed in milliseconds, that's is exactly why a PTT input is needed.
The first thing the AH-4 does at the start of the tuning process is connect the transmitter output to a resistive bridge, presenting a load close to 50+j0 to it, then it activates the PTT signal to the tx and uses small part of the RF energy to run the tuning process. At the end of it, the AT removes the PTT signal, bypasses the bridge and informs the result of the tuning process. Having a PTT input will protect the finals during the tuning, allowing us to use the AH-4 with the QDX safely.
73's Sergio.