Using analog phone outgoing on line connected to FXO line

I am trying to use an analog phone to call out on a line connected to a TDM410-FXO line. Asterisk answers as soon as I go off hook. Is there a way to have Asterisk answer on ring voltage so it will ignore the off hook condition?


Hi Roy,

You can certainly use the Answer application :smile:
Here is some sample dialplan


exten => 908070,1,Answer()
exten => 908070,n,Playback(hello)
exten => 908070,n,Wait(2)
exten => 908070,n,Dial(ZAP/1/908070)
exten => 908070,n,HangUp()[/code]

Hope I understood your question properly :smile:


An ordinary phone cannot generate ringing voltage!

Although there is some ambiguity between FXO and FXS, I think you have the type of line card that sources ringing voltage. Even if it has the hardware to support detecting ringing voltage, I wouldn’t expect a PABX to take advantage of it. (Anything could happen, but it seems rather unlikely.)

What are you trying to achieve? How is your phone able to generate ringing voltage?

Im sorry that I did not explain my condition properly. I have a telco line that has both a digium port and a telephone connected to it. Since my asterisk/digium is used for demonstration purposes right now, the line to the telco sits there and seldom is used. I was thinking, wouldn’t it be nice to use that line as an outgoing line from the phone that shares the telco line while asterisk is idle. I was hoping asterisk would not even know that the line was being used but it senses the off hook condition and answers as if the off hook was an incoming call.

I found out from digium that the service would be erratic if you use a phone on that line that is meant to be the FXO line for asterisk

Thanks very much for replying… This is the first forum I have used and I am impressed that you took the time to answer me. Have a good day.

Load the driver like so:
modprobe wctdm24xxp battthresh=20