Microphone Switching Relay

This was constructed for a project with a divisible room.   Each side had a conventional induction loop system with a room microphone.  When the rooms were combined the mics needed to be combined and the combined feed sent to both amplifiers.

This switching needed to be controllable by a simple relay.

What I ended up with was a bunch of relays controlled by a relay.

Relays

A relay is a pretty simple device. It’s basically a switch that will switch when it has power, and switch back when it doesn’t. If you have a few of them working together they can be used for all sorts of things, including redirecting microphone signals.

Power & Control

In order to control the switching the power to the relays needs to be switchable. Some control processors have a controllable 12v output, some don’t. Usually they will at least have a relay. My design will allow either to be used, but was used with a processor with only a relay available.