[HELP] Getting started with asterisk with modem card

Asterisk Asterisk Support
1

I am trying to experiment with Asterisk in Linux, first using a Conexant modem card with a Linuxant HSF modem driver. I can run asterisk -vvvc (runs a console) and I can type “dial” so it uses the soundcard like a phone and plays the sample menu on the speakers. (To dial extensions I have to type "dial " into the console.)
However, I have no idea how to get the modem recognized by and integrated into Asterisk. I am successfully able to use the modem with the kppp program, so at least the Linux operating system has it registered. Also, the Linuxant driver and modules were installed with the “free” license that gives a approx. 14Kbps limit.
When I type “console”, it says it is using the “dsp” device. It uses the “OSS/dsp” channel during a call. Typing “console /dev/modem” or “console modem” gives an error. I obviously don’t know what I’m doing.

In short… Please help me get Asterisk to use the modem. I will be happy when I can hear the Asterisk menu on the phone attached to the modem.

2

Sorry you need a FXO / FXS card (yes they are voice modems but only a few chipsets)

the real deal TDM400P (about 140.00 I think is the loweset with a single port)

For a cheap junker plenty of Echo and bad sound look for X100P on Ebay
about ten bucks and in most cases over priced at that.

3
  1. So you’re saying that Asterisk can only use one brand of modems? Why can’t it use modems in general?
  2. FXO/FXS cards appear as regular voice modems, right? Let’s pretend my card is an FXO/FXS card – what would I do to use it with asterisk, step-by-step? (I’m asking because perhaps there are limited functions the one I have can actually be used for?)
4

Asterisk only supports a certain type of Intel Tiger Jet voice modem. This device was for a while rebadged as a Digium X100p, thus the Asterisk support. Many clones are available on ebay. However as bubba said they are junk, it is common to get bad sound quality, unsolvable echo, various caller id problems, etc etc. They plain old suck.

Theoretically if * created drivers for other voice modem chipsets then it could use them. However nobody bothers to because (among other reasons) there are a very large number of them to try to support, and there is not a large demand for supporting them. Most of the people who use * (vast majority) would rather pay a few bucks extra and get something more reliable.

If asterisk says its using OSS/dsp that means that it is using your sound card (or trying to). Asterisk can use a machine’s sound card as a ‘phone’, which is controlled from the * console. This is often used for overhead paging systems- connect the * box speaker output to a paging amplifier and overhead speakers.

I would highly consider that you look into one of the many telephony boards that are available, the Digium TDMxx series and Sangoma A200 series are both excellent products and for a single-fxo (same as voice modem- one phone line connection) card is usually around $100.

That said, if you want to hack at it anyway-
First, don’t use Dial at the console cuz it’s not as useful IMHO. I suggest get a free softphone program like SJphone voip-info.org
Set up that (sip.conf and extensions.conf) so it can dial a few things like echo test etc.
Then in the softphone’s context (extensions.conf) make a line like
exten => 1234,1,Dial(Zap/1)
that should pick up Zap/1 when you dial 1234.

Then make zap/1 exist. set up /etc/zaptel.conf and /etc/asterisk/zapata.conf to define channel 1 as an FXSKS type (fxo cards use fxs signalling and vice versa, yes I know it’s backwards).
Then start zaptel, and restart asterisk, and dial 1234.

You will almost certainly get nothing. Sorry :frowning: