Telephone communication is a rather old invention, it was invented at the beginning of the 19th century, and to date there have been no fundamental changes. The telephone itself has become completely different, but the principle of operation is almost the same.
Materials and tools for homemade:
• two telephone sets;
• the wire;
• batteries or a 20 volt power supply;
• patch cord (telephone wire).
Telephone network manufacturing process
Step 1. Choosing a cable
For home almost any type of wire can be used in the telephone network, in this case the author used a twisted pair cable 25 meters long. If necessary, you can use a longer wire, there are no strict restrictions.
Step 2. DC source
In a regular telephone network, the voltage is from 60 volts, during a conversation the power rises slightly. For a home network, 20 volts of voltage will be enough, it can be supplied by two Krona batteries or a power supply unit of the corresponding power.
Step 3. Connection
For this procedure, you need to take a telephone wire and cut it in half. It has very thin veins; it is impossible to strip them with an ordinary knife; they must be burned. If the batteries will be used, you need to connect them in series, you can use contact clips, but this is not a prerequisite and without them everything will work. The current source is sequentially connected to the circuit, the contacts must be isolated.
Conclusion
After connecting, you can use the mini-network, but its only drawback is that there is no way to call another subscriber. To make this possible, it is necessary to provide alternating voltage in the telephone line, as is done in ordinary telephone networks.