POTS Telephone PC interface for hobby work?

[Invincible Sugar]

Hi. I have an old POTS telephone I'd like to play around with. I know there are VOIP solutions like magic jack to give the phone a working number and dial tone... but are there any other gadgets to reuse older phones for other purposes? Something you can plug into a computer that lets you route audio from the PC to the phone? Or use the phone microphone as your PC microphone? Or use the phone for Discord or Skype calls... or use the dial pad like a num pad for text input... or make the handset ring at the press of a computer keyboard, key... etc?

 

Ideally I'm looking for a mass market gadget, but I'm also open to hobby projects you might know about as long as set up is not too technical... I can't program a raspberry pi or anything. Plug and play would be ideal.

 

Thanks!

[OddOod]

I have no experience in the field, but if it's a real old phone, you could probably rewire a headset cable into a phone line with these diagrams using little more than your teeth and some electrical cable. If you have a multimeter that makes testing continuity easier

 

[Invincible Sugar]

18 hours ago, OddOod said:

I have no experience in the field, but if it's a real old phone, you could probably rewire a headset cable into a phone line with these diagrams using little more than your teeth and some electrical cable. If you have a multimeter that makes testing continuity easier

 

Interesting, thank you! I might play with that... I do have the parts I'd need.

[OddOod]

If you remember, lemme know how it goes. I'm curious.
As for the dialpad, IIRC when you press a button it outputs a specific frequency. If you get the wiring right, and I'm not wrong, you might be able to use Audacity to see the tones. Then you'd have to either scour github for some audio processor to interpret them, or write your own

 

[Invincible Sugar]

2 hours ago, OddOod said:

If you remember, lemme know how it goes. I'm curious.
As for the dialpad, IIRC when you press a button it outputs a specific frequency. If you get the wiring right, and I'm not wrong, you might be able to use Audacity to see the tones. Then you'd have to either scour github for some audio processor to interpret them, or write your own

 

Personally that's more advanced than I have the skills to figure out, if someone else had already done all the work and made a tutorial I could probably follow it but I only surface level knowledgeable about these things, I can copy paste code into a program but I wouldn't know how to code a program.

 

I'll do some more research into this, if I end up coming up with anything interesting I'll keep you in the loop!

[Needfuldoer]

On 7/2/2022 at 8:13 PM, OddOod said:

I have no experience in the field, but if it's a real old phone, you could probably rewire a headset cable into a phone line with these diagrams using little more than your teeth and some electrical cable. If you have a multimeter that makes testing continuity easier
 

[snip]

This might work for a bare handset, but absolutely do not connect your computer to a real phone line this way! POTS lines carry high voltages (to make your phone ring), if someone calls the line while it's plugged in, your sound chip will be zapped by a 48v square wave.

 

You can use a modem as a telephone (greybeards will call this "telephony", rhymes with "Stephanie"), with the right setup.

 

https://docs.microsoft.com/en-us/windows/win32/tapi/microsoft-telephony-overview

 

If you have an analog phone line available, or you can get a phone line simulator or small PBX, or just build a circuit to fake a simple circuit with no ring capabilities, you can "talk" to the phone with your modem. 

 

I have absolutely no idea if this still works with USB modems, or even "WinModems".

 

Or if you're feeling very adventurous, you could set up Asterisk and use a POTS phone adapter to turn the analog phone into a SIP phone, which you can then call through Asterisk with a SIP client on your PC.

 

Be warned, Telco stuff is a mile-deep rabbit hole that's simultaneously in the 1890s, 1980s, and 2020s. The more you learn about it, the more you find you need to learn.

[Slayerking92]

https://www.amazon.com/Xtreme-Technolgoies-XLink-Bluetooth-Gateway/dp/B08RXF16XD

 

LGR made a video on this thing recently.