[queued] TEAMS-, ZOOM-Headset by upcicling an old Phone


A while a go I found these two beautiful old phones in my parents cellar. A wall-mount PTT Model 50 (manufactured 1954) and PTT Model 70 from 1976.
Bothe were very popular Phones in Switzerland.
After have a look inside, they where still in very good and functional conditions. But you know, these times are gone where analog phones worked.
So my thought was to give them a new live, by upgrading it for todays Video-Calls and Conferencing with MS TEAMS and ZOOM.

Based on a Teensy 4 plus Audio Board the Phones working now as Audio-Device (Headset), Keyboard (Dial Numbers) and Serial Interface.
If you pick up the phone, a sinus tone is activated to emulate the line tone.
The Dailer works as well and the designated Number will be printed by the USB Keyboard Function.

While a call is coming in, (Detected by Audio Signal coming from the PC over USB). The Ringer goes on. After picking it up, a key combination is send to tell the application to accepting the call. Put the Phone back to the hook it sends the key combo to end the call.

The Bell is working as well :)
Using an DC/DC Upstep Converter to 24V the coil has enough power to ring the bell. Slower than original but is rings.

And Last but not least there are a button to mute the Microphone and a second to switch between MS TEAMS and ZOOM key commands.

So at the end ist fully operational as back in the old times and can even more.
It makes so much Fun, when it rings and talk to the colleagues by the old phone.
Many Laughts and big Eyes are for sure.

So it would make me happy if you put this to the Blog:
If anyone is interested in the Source... just write me an e-mail on mike@utzs.ch



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This is in the queue to get a blog article (likely within the next few months).

I hope you'll consider putting the source on a site like Github. This is a fun project I'm sure some other people would love to build, if the source and needed info is published.
Dear Paul
Thank you very much! I really appreciate.
I`ll put the source and schematics to Github in the next days. You can use this Link: https://github.com/UTZbox
There are few other projects for teensy as well :)
Kind Regards