| 摘要 |
PURPOSE:To provide a cordless telephone set with a secret talk function and interphone function, by providing a means of disconnecting the circuit of a station other than a master station or subordinate station while the master station or subordinate station is engaged with the line wire, and by disabling the means to operate in interphone operation. CONSTITUTION:The master station is provided with a transmitter-receiver and connected to the subordinate station by radio, and the interphone of the subordinate station can be connected to its line wire. While telephone set 2 of the master station is engaged, relay RY-5 is excited through the operation of circuit connection detecting circuit 27 to disconnect the circuit of the subordinate station. When the subordinate station is busy, closing the answer switch generates tone signal f2 and the master station has relay RY-1 excited to hold itself in a transmission state; and line wires L1 and L2 are connected to the subordinate station via relay RY-2 to offer the master and subordinate stations the secret talk service with the line wires. For an interphone call, relay RY-3 is excited and the means of disconnecting the circuit is turned off to connect the master and subordinate station together. |
