Freepbx with Bogen PCM

I’ve run into a snag and I’m hoping you may be able to help.

This one client previously had a digital phone system with two amplifiers and one Bogen PCM unit that allows the system to choose a paging zone by using dtmf. This was done by using a CO trunk line of the digital system. So the end user presses 9 to access the trunk, they hear a tone generated by the Bogen PCM, then dial 0, 1, or 2 to page to the intended zone.

So I need to duplicate this. I need to press a code on my Freepbx, that will access an FXO port(currently trying Grandstream T813 and a Yeastar TA410), giving a dial tone, NOT trying to complete a call all in one shot, then be able to dial DTMF to choose the paging zone.

I have the FXOs registered, but when I use the outbound route to access the trunk, its giving an all circuits are busy right away. I believe this is because the FXO is expecting a 10 digit phone number to dial. Where I need it to just go off hook and let me go from there.

Is this even possible? Is there something I can do in the freepbx to allow this or do you think the FXO needs adjusting?

Using FreePBX

What sort of configuration did you do to the Grandstream gateway?

The only changes I’ve made was to register the FXO with the system. For the Grandstream I had to enable ChanSIP which I really didn’t want to do. Couldn’t seem to get it registered using PJSIP. So I hope this answers your question, I followed this video.

So typically in a sip environment there is no such thing as offhook. You have to dial a number to reach the Grandstream gateway. How do you have it configured to reach the gateway?

Can you provide the asterisk log of an attempt where you are dialing the number for the gateway?

Is this on the same network? Why is it trying to do NAT?

Is this really important? IMO, it’s cleaner if the user dials 5990, 5991, or 5992 to page the desired zone. That way, you can e.g. have a speed dial button to page a specific zone, or hit redial to repeat the last page. It’s also a simpler setup.

The problem is you can’t dial ‘nothing’ on the trunk. If the FXO device supports it, you could have its dialplan rewrite some code to [null] and you’ll hear dialtone from the Bogen. If not, you could try sending e.g. a DTMF A, hoping that the Bogen won’t recognize it and continue playing dial tone.

The clients will be on the same network, I only have a hosted pbx in my office to test with. I just realized there was a mistake in the TA though.

Going back to what you said however,

sip environment there is no such thing as offhook.

This is what led me to believe this wont work anyway. Is it possible to be able to just go off hook? Or maybe have 3 speed dial buttons for the three page zones with some Pauses for the dtmf?

Yes, but that is added complexity as well as more hassle for the end user.

Is this really important?

Its not at all.

Its two zones, and the “3rd zone” is just both. So they have two amps, I would want to have the ability to reach each zone, or both at the same time.

Typically I use a Snom PA1 for paging interface.

What do you think is the best way to go about this?

Set up your Outbound Route with
prepend: (leave blank)
prefix: 599
match pattern: X
callerID: (leave blank)

The user dials e.g. 5990, the PBX sends 0 on the trunk, and the FXO device sends DTMF 0 to the Bogen.

Of course, you first have to get the trunk working properly. Your log showed it wasn’t reachable.

Yeah I had the TA still registered to another pbx on accident.

The user dials e.g. 5990, the PBX sends 0 on the trunk, and the FXO device sends DTMF 0 to the Bogen.

Is it really this simple? Do you think I would need a pause?

The HT813 allows you to configure the delay before it sends DTMF; default is 500 ms. I would expect other FXO devices to have a similar setting. There is also often an option to wait for dial tone before sending, though that might not work if what the Bogen plays is non standard.

You could use a sip paging adapter and save the headaches.
Algo, Bogen, Valcom, and Cyberdata come to mind.

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Sure, but most don’t have the multi-zone and combined zone features the OP desires. Those that do are $$$$.

Plus the Bogen PCM was existing, and its for a nonprofit school so budget was key. Your prefix outbound route was all that I was missing. I had 599 in the match pattern thinking when it matches this, use the trunk then go “off hook” etc… My mistake

Thank you for your help Stewart and everyone else!

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