Integrating 3CX into an intercom system

[Paul Omans]

I thought this was pretty cool, so I wanted to share. This last week, I onboarded a client who had an old analog phone system that was integrated into a PA system around their shop and warehouse. When they pressed the intercom button on their phones, it sent an intercom to the speakerphone output of all their phones as well as an RCA jack plugged into the PA amplifier. In order to keep that functionality with the new VoIP 3CX phone system, I created a page group that included all the new VoIP phones and I put a custom speed dial on each phone labeled "Intercom" which dialed that page group. Although this worked to send an intercom message to each phone, I still needed to integrate the old PA system with the audio sent over the intercom speed dial. To do that, I used a dedicated Yealink T42G which by default sends all audio (including page audio) through its headset connection when headset output is enabled. I connected an RJ9 to 3.5mm adapter to the headset connection on the T42G and then I used a 3.5mm to RCA adapter and then I added the T42G to the page all group so when someone presses the "Intercom" speed dial on their new VoIP phone, all the VoIP phones send the intercom audio through their speakerphone as well as the T42G which send the intercom audio out of its headset connection and through the PA system. Although this is a "quick-and-dirty" fix I feel that it is stable enough to keep as a permanent solution for having audio from 3CX go through an existing intercom system.

 

[Paul Omans]

I wanted to update this thread in case anyone comes across it looking for a way to integrate an existing intercom/public address/PA system into 3CX. Snom (one of the supported 3CX IP phone manufacturers) released a product called the PA1 for bridging 3CX with an existing PA system. Here are the links to both the Snom product page and the 3CX configuration guide:

https://www.snom.com/broadcasting/public-address-system/
https://www.3cx.com/sip-phones/snom-pa1/

 

[Paul Omans]

Use Snom PA1. much more easier to connect SIP to analog paging system

Correct, please see my post above explaining that exact product. The reason I took a more complicated route in my first post is because 1. I was under a time crunch and I did not have the ability to wait for additional hardware to be delivered, and 2. I was not aware Snom had a product specifically designed to address this issue.

 

[jbryant84]

We used to dismantle a phone and splice into the speaker wires. We've been using PA1 adapters instead, they have a few output options, so we've been able to integrate them into any setup thus far.

 

[Paul Omans]

Want a super cheap solution to overhead paging on 3CX?

Purchase an inexpensive entry level IP phone, take the backing off the phone, and connect the pair of speakerphone wires, to the audio input on your amplifier. Register the phone to your 3CX as an extension, and add it to your paging group. Now when you make a page to the paging group, it will amplify over the speakers. Ta da!

That's exactly what I did, explained in the first post in the thread.