Hi All, This will no doubt be one of those blindly obvious problems but .... I'm reasonably familiar with Asterisk in normal IAX/Sip type environments. I've just built my own repeater system basically using ACID to get an idea of the technology. I've removed the Allstar registrations and reg script as it is a single node stand alone system at the moment. A lot works. Morse ID, announcements, and audio (from dialing in on the phone patch) are all transmitted. However try as I might I can't get audio from the receiver input to be passed to the transmitter or to a phone extension and the TX is never keyed from the receiver. The usbradio.conf file is set as I understand for carrier squelch: carrierfrom=usb ctcssfrom=no The radio tune procedure worked pretty much OK (except Asterisk crashed when I ran the radio tune txtone 0 command but all other radio tune commands are fine). DTMF digits are also all received and decoded OK as reported by debug output but no audio to the phone line when the auto patch is up. When the patch is up the TX keys fine. The squelch from the radio is recognized by the USB interface as I get radiochan_usbradio NOTICES showing that rxcarrierdetect is following the radio mute OK. But Rpt stats indicates signal on input = no and doesn't change. The rpt.conf file is the example other than the node number and I've also tried adding duplex=4 to the node context but this doesn't change things. A possibly related question is the purpose of the [radio-secure] context in extensions.conf. What is its purpose and where is it referenced from? I already have a context for incoming telephone calls to the system ie 1234,1,Rpt,1234|D Suggestions appreciated! Regards, John ZL4JY