The TC-Z912 infrared transmitter is a microprocessor based central unit which is designed to modulate and transmit 12 audio channels to different carrier frequencies. It features independent channel level control, independent channel output level indicators, and independent channel audio output sockets for sound recording. Test mode produces a different frequency tone for each channel. Two BNC sockets can link up infrared radiators in two lines. A transmitter can connect multiple interpreter consoles in a daisy chain.