DTMF wireless paging system

Relevant key device information applied in this article: UM97085 S%26;P27A 7806 S%26;P27B YN9101 CD4511 KD9561 9013 8050 uses the dual tone multi-frequency encoding signal output by the DTMF encoder to modulate the transmitting carrier frequency, which can form a DTMF Coded radio paging system. This circuit uses DTMF encoding circuit UM97085 and decoding circuit YN9101 to form a small wireless paging system, which is used for internal paging in small enterprises. It is convenient and economical. As shown in the figure, (a) shows the DTMF encoding radio transmission Circuit, Figure (b) shows the radio reception demodulation, DTMF decoding and audio signal sounding circuit.