IrDA-9000 --Products link-- <UHF models> QR-4000U UDR-1000/2000 IrDA-9000 SDR-8200 SDR-7200 SDR-5000 SDR-2816SC/1816SC AIR-812/813 R-612/613 <VHF models> SDR-1216/2216 AIR-212 R-303/304 R-1001/2001   2-way Sinc. True Diversity Wireless Microphone System       Receiver Handheld Beltpack   IrDA-9000 General Features   • Patented IrDA technology for 2-way data transfer between transmitter and receiver. Taiwan patent No. : 94128675. • New compandor system adopted totally eliminated noise of the previous generation compandor circuit. • High-efficiency DC-DC convertor circuit design largely reduces current consumption and heat. • Digital volume control for precision setting and low noise output. • Half 19” metal casing receiver. • Transmitter battery weak indicator.