TX/RX Gain per channel

Where do I put tx and rx gain to effect the individual channels?

I am really craving additional command input fields under edit for the DAHDI channels as well as under the general option.

For now, what is the location and format to manually do so in something like dahdi_channels_custom.conf?

You can not set gains on a per channel its a global setting only.

That’s not true Tony, one’s dahdi channels are initially defined in /etc/dahdi/system.conf and you can set the channels up individually and apply anything appropriate to that channel there.

Perhaps, Schmooze considers it a “global” in it’s GUI but for more granularity, that requires bash access to your system, the OP obviously needs to learn to do that :slight_smile: but with that knowledge, she will be fine.

Just for what it’s worth, unless you have a “bog standard” PRI or two getting timing from the net,then all that dahdi module crap just doesn’t work very well, whoever wrote it. so I advise generally to not use it and DIY :slight_smile:

I never said it could not be done at a config file level. He asked about doing it in the DAHDI module which I responded it was not possible Dicko as its a global setting in the DAHDI module.

I misunderstood, I thought you said you said:-

. . .You can not set gains on a per channel its a global setting only. . . . There was no caveate, I simply corrected you.

I just revised my post to cover exactly your post . . .

But hopefully Jessica is no longer stymied and can do exactly as she wants.

I guess that portion of my post was missed as I am aware of how it works now. Thanks for current workaround dicko.

Dicko, where can I find more details on issues with DAHDI which cause problems as I am currently using it and need to know where any landmines are?

Not really a workaround, it has always worked like that, even when it was zaptel, maybe the dahdi module will be rewritten for “the rest of us” one day. . . You never know, maybe someone will someday need an AMI/D4 connection to a legacy PBX with e&m signaling and authoritative timing.

I’m back through the looking glass (SSH). etc/dahdi/system.conf has a big warning not to modify. Inexperienced as I am, I need a reliable location and syntax and procedures. Pushy aren’t I.

Landmines are often caused by using incomplete software to setup your dahdi channels. you really have to understand PSTN to get the best from it, and every implementation is unique. Understand that dahdi is neither part of asterisk nor part of FreePBX, they just use it as appropriate.

I don’t know what your problems are, I conjecture badly setup FXO/FXS interfaces, possibly echo or just pissed of users . . .

Ignore it, it’s probably that incompetent dahdi module. if you get rid of that albatross and run


it will autogenarate, depending on your


file, and will be equally wrong. So I suggest you just do it the old fashioned way (by hand) and you will a) understand and b) have a working system.

Well I guess you are offering to re-write it with all those PHP skills you told me you had and all your vast experience. Its not a Schmooze Module like you seem to think. It is a Digium module that we gave some TLC to make it work again and add missing things but we could not add everything.

Please feel free to add the remaining missing features.

Problem: Audio on my PSTN channel is to low.

Tony, can you end this nightmare and tell me exactly what I have to enter to adjust the audio levels on individual channels rather than just globally (while I wait for Dicko to add custom fields to the DAHDI GUI)?

Tony, you are pretty well wrong in everything you posted. I PM’d you sentence for sentence. I am absolutely happy editing my /etc/dahdi/system.conf file. It has always worked, and surprisingly, still does.


is an easy way to look at the unbutchered version, just effing read it folks!

The DAHDI module does not allow for this. Sorry. It only has gains at a global level. You would need to hand configure your dahdi card to do this as Dicko said.


I never once said gains could not be done per channel in DAHDI in general. The post from the OP was obvious he was using the DAHDI module in FreePBX and my whole response was around its not possible in the module as that is what he was asking about. Its a global only setting in the module. Please quit trying to change the focus. The user is asking about the GUI as he just asked again how to do it in the module and I am trying to tell him he cant.

I remember from the original post

“. . .For now, what is the location and format to manually do so in something like dahdi_channels_custom.conf? . . .”

so please don’t go there, if it was obvious that he was using the dahdi module, but was prepared to manually reconfigure is possible, I posted the solution even against your BS categorical denial that it was impossible, you were even courteous enough to agree, the module is just not ready for prime time and needs more TLC.

The focus will always be in these forums to help a poor sucker out, I believe I did, you , hmm not so much . . . right?

Also you should look at the module again. Sounds like you have not used it in 2.10 in the past 5 months when we closed over 50 bugs and features in it. 95% of things can now be set in the GUI for DAHDI including Sangoma cards using wanpipe.

One of the few things that did not get done was setting custom settings at a per channel basis but you can set custom settings for almost everything else.

And I am pretty sure your example above can be done in the DAHDI module now but do not have time to verify that.

Hmmm unless I missed something pretty sure this is what you stated was not possible.