The telegraph is an exercise not only in basicĀ circuitry, but also in problem-solving, communications, and teamwork.
Each team builds two stations, each of which can act both as transmitter and receiver, separated by a long twisted-pair wire linking two separate rooms.
The teams have to create a communications protocol, enabling them to transmit not only message information, but also flow-control signals such as Request to Send, Terminal Ready, Resend, etc.