Hi,
you can also test it with the Diode function if your AVO has it which operate at a higher voltage.
But the simplest test if a GND PTT line at the tip of connector is working is if you
- enable both the +5V and the GND PTT in the configuration menu and
- then measure the voltage between the tip and ring.
It should be around +5V.
--
73 Bojan S53DZ
