This infrared transmitter use PWM (pulse width modulation). The transmitter is equiped with LM567, tone decoder circuit. Audio signal ( at least 50mVvv ) is amplified with T1 and then it is used to ...
The CMX823 programmable paging decoder IC is a high performance, low power audio tone decoder. It supports tones from 280 kHz to 3.5 Hz and allows users to create their own tone frequency alphabet for ...