VOIP FXO Gateway

rm501

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Hi

Does anybody know of a good FXO gateway that works well with SA PSTN? I currently have a Digium TDM400 wildcard, but we having issues with hangup detection. I came right with telkom, but looks like with MTN and Vodacom incoming calls, the system cannot detect hangup.
I was wondering if there is a good gateway (4 FXO port) that's ICASA tested for SA to use with Asterisk.

Thanks
 
There is only one way to handle analog trunks in Asterisk, and that is get rid of them and go ISDN. You will never regret changing to ISDN.
 
If ISDN is not an option, I have had success with the quintum range and hangup detection.
 
Your problem is probably with the "hanguponpolarityswitch" settings in either Asterisk and/or on the cell routers. Normally you can connect a serial cable to the cell routers to program this.
 
Thanks for the feedback.
@Solar: I'm glad you mentioned the quintum range, as that's what I'm considering. Thanks!

Also, we having a problem with the volume received to party's on the other end of Telkom lines. In other words they complain that we sound too soft. I have adjusted the txgain and rxgain in chan_dadhi, but this makes no difference. I'm using Grandstream GXP285 phones. We can hear the person on the other end loud and clear, its just we sound too soft.
Any ideas or suggestions would be appreciated.
Thanks again.
 
Simplest, cheapest and quickest solution is just to port your land-line phone numbers to an operator that can deliver the calls to you as pure VoIP. No mess with levels, hardware, hangup, etc. No new hardware cost. 3 working days. Continuous service: no interruptions for line conversion and installation of the new hardware; the VoIP trunk runs live in parallel with the analogue lines for a few days in advance so that the cutover is seemless.

If that is not an option, then I have to agree with WarwickW: convert to ISDN BRI.

The Quintum gateways are among the best available in SA. I have a 4-port FXO Quintum unit that has spent most of its life in its original box as the client cancelled the order and since then it's just been used for occassional testing. If you want to buy it cheaply, you're welcome to make an offer. It's in the original box with original cables, manuals, etc.

Levels are a pain with analogue lines, however, as quite a softly spoken person, I have had issues with Grandstream GXP2000 phones before with exactly what you're complaining about: i.e. microphone versus speak level inconsistency. It wasn't a problem for my colleague who speaks loudly, but a big problem for me as I tend to mumble. Fact is, people can hear me clearly, despite my soft voice, on a Snom, LinkSys, Siemens or Yealink phone. Aside from that, I won't touch Grandstream any longer as their firmware is often buggy.

To the best of my knowlege, the newer GXP285 does have a setting that allows you to boost the microphone level without boosting the speaker, at least if recent firmware is installed. I think that this is the very first thing you should look for. If the phones arn't right, you can change the lines until you're blue in the face. The easiest way to test the phones would be to call between two extensions internally. Just ensure that you are in different rooms and cannot hear one another in the background at all. If you can, either borrow another make of handset, or, download and install X-Lite softphone and see if people can hear you clearer through that.
 
-1 for Grandstream. It's cheap and nasty. We've used one or two in the early days and they all had issues. Buzzing noise when you lift the receiver (even before making a call), bad quality calls and short meantime before failure.
 
I'm currently using a Grandstream GXW4104 for our two incoming PSTN lines.

I've managed to come right with hangup detection, and it seems to work reasonably well. The only problem I am currently having is that I am trying to setup the caller ID recognition, and it is giving me no joy with that. Otherwise seems like a nice piece of hardware.

BTW - if anyone has any pointers on the CID issue, pls pm me ;)
 
GWX4104 Hangup Detection config

I'm currently using a Grandstream GXW4104 for our two incoming PSTN lines.

I've managed to come right with hangup detection, and it seems to work reasonably well. The only problem I am currently having is that I am trying to setup the caller ID recognition, and it is giving me no joy with that. Otherwise seems like a nice piece of hardware.

BTW - if anyone has any pointers on the CID issue, pls pm me ;)

Can you please post the config? I am struggling with hangup detection.
 
Hi Jaq316,

Not sure if you got the response to your PM last week, but for everyone else's benefit, here it is again.

This is the current config on one of my customers setups. They have 2 Telkom Lines coming into the GXW4104, and the PBX software is 3CX.

Both hangup detection as well as CID are both working great with these settings.

FXO TERMINATION SETTINGS
Enable Current Disconnect - Yes
Threshold - 100
Enable Tone Disconnect - Yes
Enable Polarity Reversal - No
Silence Timeout - 20
Enable Call Answer Supervision: No
Incoming Call Ring Timeout: 10
AC Termination Impedance - 3

CALL PROGRESS TONES
Dial Tone - ch1-4:f1=400@-10,f2=0@-10,c=0/0;
Ringback Tone - ch1-4:f1=400@-10,f2=0@-10,c=40/20-40/200;
Busy Tone - ch1-4:f1=400@-10,f2=0@-10,c=50/50;
Reorder Tone - ch1-4:f1=400@-10,f2=0@-10,c=25/25;


Also while I'm at it - There are some settings out there for Caller ID that didn't work for me - My settings:

Number of rings before pickup - 3
Caller ID Scheme - 2
Caller ID Transport Type - 4

If you need any more info, just let me know.

Good Luck!
 
Hi Jaq316,

Not sure if you got the response to your PM last week, but for everyone else's benefit, here it is again.

This is the current config on one of my customers setups. They have 2 Telkom Lines coming into the GXW4104, and the PBX software is 3CX.

Both hangup detection as well as CID are both working great with these settings.

FXO TERMINATION SETTINGS
Enable Current Disconnect - Yes
Threshold - 100
Enable Tone Disconnect - Yes
Enable Polarity Reversal - No
Silence Timeout - 20
Enable Call Answer Supervision: No
Incoming Call Ring Timeout: 10
AC Termination Impedance - 3

CALL PROGRESS TONES
Dial Tone - ch1-4:f1=400@-10,f2=0@-10,c=0/0;
Ringback Tone - ch1-4:f1=400@-10,f2=0@-10,c=40/20-40/200;
Busy Tone - ch1-4:f1=400@-10,f2=0@-10,c=50/50;
Reorder Tone - ch1-4:f1=400@-10,f2=0@-10,c=25/25;


Also while I'm at it - There are some settings out there for Caller ID that didn't work for me - My settings:

Number of rings before pickup - 3
Caller ID Scheme - 2
Caller ID Transport Type - 4

If you need any more info, just let me know.

Good Luck!

Thanks for the info bud. Got a GXW4104 today and have been struggling with the hangup detection - gonna try this out tomorrow morning :)
 
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