The SZI 1029 is a high-power infrared radiator/emitter for use with all wideband and narrow-band modulators, available in 5 W and 10 W radiating power. The radiator is automatically switched on by the RF carrier and can cover areas of up to 800 m² (5 W variants) or 1600 m² (10 W variants) in single-channel operation. High-quality GaAlAs transmitting diodes have been arranged in independent groups to ensure reliable transmission. A malfunction indicator is triggered when the radiating power is reduced by more than 30 %.