Advice for analog phone line to 4G gateway

[owiecc]

I am looking for a reasonable gateway to connect our door phone. It uses an analog line to call people. We pay ca. €70/month for a landline and we can get a €3/month 4G SIM with 5h talk limit so the time has come to drop the landline. With these savings we can get an industrial grade gateway and no one is going to cry.

Can you advise me on something good? A 12 or 24V supply would be nice because we have these voltages on a door phone UPS.

[bw2341]

I'm not using this type of gateway, but here is an example of the ideal device for your situation:

https://ztecanada.com/zte-wireless-home-phone-and-internet/

It supports 4G and VoLTE and has a built-in battery so you don't need to connect it to a UPS.

However, this model is built for the Canada/USA market so it doesn't have European LTE bands. Maybe band 7 might work? Also, if you buy a used one from Canada/USA, it is very likely to be carrier locked. Even worse, they would be designed for Canada/USA analog telephones which are not the same electrically as European ones. Your door phone system is unlikely to have changeable settings to allow it to work on Canada/USA phone lines.

Check with your local mobile carriers and phone sellers to see if a similar product is available. Some local wired ISP/telecom providers also market these products to serve customers outside their wired network area. You could also search for wired telephone service in your country to see if independent providers offer this type of product as an alternative to the traditional wired providers.

You can also contact credit card payment, alarm system, elevator service and access control companies in your country to see if they have a industrial version of a voice gateway. They may not be willing to outright sell you a gateway as they usually charge monthly fees for their service.

If you have wired Internet close to your door phone, you can also try an analog telephone adapter and paid over-the-top VoIP service.

Edit: phone line electrical compatibility

[ralphrmartin]

An alternative approach is to get something like a Fritzbox to connect the analog doorbell-come-phone to the internet, and use any VOIP service with outgoing calls.