Project Overview

I dubbed this project the "TeleTone Switch", as it contains two devices used as microphones, both native to the original handset. The mouthpiece for these handsets is a carbon microphone requiring phantom power; this one uses +48V phantom power that is standard in today's microphones that require it. The earpiece is likewise wired to act as a separate dynamic microphone that can be switched to. Both have a vintage telephone sound, albeit different from each other. I made a handful of these and shipped them to several people; I'm hoping to hear some neat projects made with them. We'll see!

This project, for me, started when finding an old handset at a thrift store and wondering what I could do with it. After getting it home, I found this YouTube video which had schematics for the internals. It's a pretty simple project; most of the work is already done in the schematic. The hardest part is getting everything to fit in the handset if you're soldering point-to-point style.