Finnegan, Henderson, Farabow, Garrett & Dunner
DTMF signal discriminating circuit
 A DTMF signal discriminating circuit for a remote control apparatus, the DTMF signals corresponding to a plurality of predetermined operating modes of the apparatus, the apparatus including in OGM signal generating source responsive to an input signal from a remote source for indicating that the apparatus can receive DTMF signals. The DTMF signal discriminating circuit includes a signal coupling circuit for selectively supplying the OGM signal to the remote source and receiving the DTMF signals from the remote source, including a circuit for suppressing the OGM signal for substantially preventing operation of the apparatus in any of the predetermined operating modes in response to receipt of the OGM signal by the signal coupling circuit, a discrimination circuit for receiving the DTMF signals from the signal coupling circuit and a microcomputer responsive to the discrimination circuit for controlling operation of the apparatus in an operating mode corresponding to the received DTMF signals. 
Kabushiki Kaisha Toshiba
H
H04M
inventional
Yasuo Yukihiko
Suzuki Sasaki