Overhead paging "hack" for the cheap, like me :)

[efounco]

OK, I know they sell SIP overhead paging modules, but they want too much money for them because it's a specialized device that caters to business needs. I also know that you can buy phones that will answer all incoming calls automatically and uses the headset jack to supply audio to an amplifier. Some people use this method but not all phones have this feature. However, for ~$4.00 and a trip to Radio Shack, you can convert just about any SIP phone that has a speaker phone into a overhead paging module. Here's how:

I used a spare SPA942. This phone is nice to modify because it's inexpensive, has POE and is easy to take apart.

Open up the phone to expose the insides.

Here's the ~$4.00 3.5mm audio jack you need from Radio Shack. It disconnects the audio to the speaker when something is plugged into it.

Using a soldering iron unsolder the wires going to the speaker.

Solder the speaker wire to the input of the plug and solder a length of extra wire from the output to the speaker. I drilled a hole in the bottom of the case and used a bit of hot glue to secure the plug.

An there you have it, a phone that you can connect to any amplifier using a mini y-adapter.

Simply set the phone up as an extension and assign it to a paging group. Use the volume adjustment on the phone to increase/decrease the output levels.

 

[willow]

you just use an fxo or fxs gateway and save yourself a phone

 

[leejor]

you just use an fxo or fxs gateway and save yourself a phone

Will an FXS (assuming it's an FXS as it is accepting a page) output the audio automatically as this set does? Have you set one up with some sort of audio adapter cable that plugs into the RJ11 jack that then goes to an amp? Can you share the schematic with us?

 

[efounco]

you just use an fxo or fxs gateway and save yourself a phone

Will an FXS (assuming it's an FXS as it is accepting a page) output the audio automatically as this set does? Have you set one up with some sort of audio adapter cable that plugs into the RJ11 jack that then goes to an amp? Can you share the schematic with us?

Yeah, I would be interested as well. I know there are some 70V PA amplifiers that support FXS/FXO inputs, but they are generally much more expensive than the ones without.

Either way, these phones cost us nothing; I'd be pretty hard pressed to find a compatible receiver and a FXS gateway for ~$4.00. And, the phones still work fine if I disconnect the audio cable...

 

[willow]

valcom and viking make paging adapters and bogen makes amps it already included

 

[efounco]

The Valcom and Viking adapters are ~$200 - ~$400 each. Bogen 70V amplifiers start at around $300.00 for the entry level models.

I'll stick with a cheap Linksys phone and a $4.00 Radio Shack part

 

[willow]

there is way more functionality in an adaptor or amp, but to each their own. As a business owner I would not support such a setup as you show and love to get the hourly billing rate to fix any issues that arise.

 

[efounco]

Well, you shouldn't worry about it then. This is a quick and dirty "hack" for technically inclined end users. I never suggested it should be marketed to customers. However, if a customer has enough technical knowledge to open up a phone and hack into the speaker, then they probably aren't paying much for 3CX support anyways.

 

[sigma1]

Snom PA1... cheap and reliable.