Lo-Fi Telephone Microphone

Watch me dissect and old phone and repurpose its carbon microphone.

Constructing a lo-fi microphone from an old telephone’s carbon microphone, and seeing what other parts we can make some sounds with.

I got this old phone at Goodwill for a couple bucks, interested in seeing if it had a carbon microphone that I could salvage. It turns out getting that microphone out was a breeze. Then I started seeing what other parts might be interesting–the keypad, the chip that makes DTMF tones. Finally, I put together the circuit for the carbon microphone, and got it back in the handset, adding a new specialty carbon microphone to my mic locker (such as it is).