AUTOMATIC ANSWERING TELEPHONE SET CAPABLE OF AUTOMATIC PRODUCTION OF WAITING STATE

• Main Author: HASHIMOTO KAZUMI
• Format: Patent
• Language: English
• Published: 23.08.1986
• Subjects: ELECTRIC COMMUNICATION TECHNIQUE; ELECTRICITY; TELEPHONIC COMMUNICATION

PURPOSE:To eliminate various inconvenient cases due to a fail where a switch for automatic waiting mode is not duly turned on, by setting an automatic answering telephone set under an automatic waiting state by means of an AND circuit for the output of a timer circuit which is stored automatically and the output obtained when an incoming signal arrives. CONSTITUTION:When an operating button STOP is pushed, a flip-flop IC-8 is set to set a terminal Q at an H level. Thus the charging of a capacitor C20 is started and a flip-flop IC-7 is set when the charging voltage reaches a prescribed level. Then the terminal Q of the IC-7 is set at an H level to activate a NAND gate G-1. Thus an automatic answering telephone set is put under a waiting mode. The call signals are detected by the photocouplers of NE and CdS, and a terminal 1 of the gate G-1 is raised up to an H level. The terminal of the gate G-1 is set at an L level for each input of a call signal. Thus a capacitor C3 is charged to set a flip-flop IC-1 and a flip-flop IC-2 is set by the pulse of a capacitor C4. Then the drive of an answer tape T-1 is started for transmission of a message.