Two-way communication device system

A two-way communication device system, comprising:

• a first two-way communication device including a controller having a clock function;
• and
• a second two-way communication device installed at a different location from a location of the first two-way communication device and configured to communicate with the first two-way communication device, wherein
• the controller included in the first two-way communication device creates an operator input operation history when the first two-way communication device receives an input operation from an operator operating the first two-way communication device for a first time,
• the controller included in the first two-way communication device transmits an input signal to the second two-way communication device when the first two-way communication device creates the operator input operation history,
• the controller included in the first two-way communication device creates an other-device input operation history when the first two-way communication device receives an input signal from the second two-way communication device for the first time,
• the controller included in the first two-way communication device sets the first two-way communication device to a first state when both the operator input operation history and the other-device input operation history do not exist,
• the controller included in the first two-way communication device sets the first two-way communication device to a second state when only one of the operator input operation history and the other-device input operation history exists,
• the controller included in the first two-way communication device sets the first two-way communication device to a third state when both the operator input operation history and the other-device input operation history exist,
• when a current time recognized by the clock function has passed the specific date and time, the controller included in the first two-way communication device (i) deletes both the operator input operation history and the other-device input operation history at a specific cycle date and time and (ii) resets the specific cycle date and time,
• each of the first and second two-way communication devices includes two arms including a first arm and a second arm, and is configured such that (i) in the first state, the two arms are lowered, (ii) in the second state, the first arm is raised and the second arm is lowered, and (iii) in the third state, the two arms are raised, and
• each of the first and second arms has a shape drawing an arc.