Saturating bipolar switch circuit for telephone dial pulsing
Security code selector for telephone access card
Selective ringing receiving device and method
Selective telephone ringing-signal interruption
Selective tone event detector and method therefor
Selectively activated dual tone multi-frequency detector
Self-compensated dual tone multiple frequency generator
Self-lighting type push button input device
Semiconductor integrated circuit for a telephone dialer includin
Sensor circuit for a telephone line
Sensor circuit for telephone line
Sensor circuit for voice/fax switch with cascaded amplifier circ
Service use device
Shortcut dialing apparatus for telephone set
Shutter mechanism for telephone directory
Signal analyzing system
Signal detecting device
Signal detection and discrimination using waveform peak factor
Signal detector with coefficient swapping transform unit
Signal detector with duration-based frame width