TX/RX Gain per channel (2014)

Distro Discussion & Help
1

There was a topic with this title which was closed last year. I need adjusting the gain on a dahdi channel, and just one, because the line connected to it is too low, and the line connected to the other channel is correct. Global adjust will do no good since the second channel would be too high.

The post I mentioned said it was not possible, if I understand well the discussion. (A user said it was, but he never gave a code to enter in a file to achieve that).

I was wondering if there was some progress on this point since last year.

I am unsure if my version of FreePbx is the last one, I am using a Xorcom 2000.

Thanks if you have any idea.

What I tried already :

<code>

rxgain=10.0

txgain=10.0

</code>

in the files chan_dahdi.conf and dahdi_channels.conf

But no success.

 

 

 

 

2

Disable the dahdi module in FreePBX and set them manually, currently the module doesn’t support such granularity and will overwrite your manual setup on each reload.

3

OK, it works.

I think the dahdi module was already disabled in FreePbx because I don't find any module like that in the Module Admin

The file to modify is : dahdi_channels.conf

  • In the code below, I set a gain of 14 dB on channel 13 (a FXO channel).
  • Notice I MUST reset rxgain and txgain in the following channel because parameters are inherited by the following channels.
  • The .0 is mandatory : rxgain=14 won't work

To restart the service without a full restart :

  • /etc/init.d/asterisk stop
  • /etc/init.d/dahdi restart
  • /etc/init.d/asterisk start

Here is the code :

; Span 2: XBUS-00/XPD-10 "Xorcom XPD [usb:X1063701].2: FXO" (MASTER)
;;; line="13 XPP_FXO/00/10/0  (no pcm)"
signalling=fxs_ks
callerid=asreceived
group=0
context=from-pstn
rxgain=14.0
txgain=14.0
channel => 13
callerid=
group=
context=default


;;; line="14 XPP_FXO/00/10/1  (no pcm)"
signalling=fxs_ks
callerid=asreceived
group=0
context=from-pstn
rxgain=0.0
txgain=0.0
channel => 14
callerid=
group=
context=default

 The reason for which my first tests did not work is probably modifications made on a wrong place.