Hi, this is Wayne again with a topic “DIY Hacks & How To’s: Phone Intercom”.
Today, I’m going to show you how you can make a simple intercom using a pair of old telephones. So the first thing that you need for this project is two corded telephones. The phones contain all the circuitry necessary for processing and transmitting a voice. Call the only thing that they need is a power source.
Phones normally get all the electricity that they need directly from the phone line, in this case, we’re using a 9-volt battery to supply the power to connect the two phones together into a basic intercom system. All you need is a phone cord, a 9-volt battery and a 300 ohm resistor. First, we need to cut open the phone cord to access the internal wires. Take a sharp knife and cut through the cord along the center then cut the insulation off one side to reveal one of the internal wires cut this wire in half and strip the insulation off the ends now connect one of the wires from the phone cord to The 9-volt battery and connect the other wire to the resistor, lastly, connect the other ends of the battery and the resistor together. This should make a working intercom system after testing it out to make sure that it works it’s time to start our everything together before making each connection put a piece of heat shrink tubing onto one of the wires, then solder, the wires together slide the tubing over The exposed part of the wires and heat it so that it fits tightly in place do this for each connection to keep all the parts together. Neatly I put them in a three by two plastic project enclosure. You just need to cut a slot in the side of the enclosure, for the phone cord hold the cord up to the edge of the box and mark the outline. Then using a sharp knife cut a slot in both ends of the top and bottom pieces of the enclosure, now carefully fit all the parts into the housing and close it up plug the phone cord into both phones and your intercom is done when you speak into One phone, the person that the other phone should hear you clearly with a typical 9-volt battery. You should get about twenty to thirty hours of you set of the intercom.
If you’d like to make this project a more permanent intercom system, you can replace the battery with an AC power adapter if you’re interested in doing this, you can check out my project on how to convert battery powered electronics to run on AC power. Well: that’s how to make a simple intercom system from a pair of old corded phones, thanks for watching and check back soon for more DIY hacks and how-to .