In this project, I show you how you can make a simple intercom system from a pair of old corded telephones. The phones already have all the circuitry that is needed for processing a voice call. All you need to add is a 9 volt battery and a resistor. This is an easy electronics project for beginners and it is great to do with children. Try it out and have fun.
Here’s the full build on MAKE: Projects and on Instructables.
See the full series here.
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My name is Jason Poel Smith. I have an undergraduate degree in Engineering that is 50% Mechanical Engineering and 50% Electrical Engineering. I have worked in a variety of industries from hydraulic aerial lifts to aircraft tooling. I currently spend most of my time chasing around my new baby. In my spare time I make the how-to series "DIY Hacks and How Tos."
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