Central Unit The TS-820RC is a Central Unit of the Infrared Conference System that allows easy installation and flexible layout. By connecting TS-905/907 IR Transmitter/Receiver, TS-820RC can control the Chairman and Delegate Units via wireless infrared signal. It features the installation confirmation function that allows the connection status of IR Transmitter/Receiver and Chairman/Delegate Units to be verified. The TS-820RC is also equipped with FBS (Feedback Suppression), enabling effective control of acoustic feedback. In addition the unit employs an MP3 recorder that makes it possible to record all conference contents to either a connected USB memory drive or internal memory. The system can be controlled by PC (*1). With the use of an optional rack mounting bracket, it can be mounted in an EIA Standard equipment rack (4 unit size).(*1) Relevant control software is supplied on a custom-made basis. The Central Unit shall include the following functionalities. “Number of Open Microphones Setting” supports a well-organized meeting. One, two, three or four persons can be allowed to talk at any one time to prevent the confusion that could result from several participants all speaking at once. “Speech Priority Setting Function” sets speech when Talk Keys on the conference units are activated exceeding the set number of authorized speakers, microphone ON/OFF operation can be set to any of the following: first-in-first-out, last-in-first-out, or last-in-first-out after 2nd unit (the microphone stays ON for the unit whose Talk Key was first pressed). “Auto Mic-Off Function” prevents inadvertently leaving the microphone on. With this function ON, the microphone will automatically switch itself off after a 30-second period of silence after the Talk Key was pressed. “Installation Status Checkup Function” for the at-a-glance confirmation of communication. If activated on the Central Unit, the microphone indicators in the Chairman/ Delegate Units light up. “Feedback Suppressor (FBS) Function” that locates up to seven feedback frequencies and sets notch filters to eliminate them. “Recording Function” allows to record in mp3 format and audio files can be stored to a supplied 1 GB internal memory or additional USB memory (up to 32 GB). With the use of an optional rack mounting bracket, it can be mounted in an EIA standard equipment rack (4-unit size). The Central Unit shall provide one external microphone input (600 ohms, -60 dBV, unbalanced, phone jack), one auxiliary input (10k ohms, -20 dBV, unbalanced, phone jack), auxiliary outputs: (1) 10k ohms, -20 dBV, unbalanced, phone jack, (1)10k ohms, -10 dBV, unbalanced, RCA jack and (1) Headphone mini jack. (1) External Control Terminal (D-sub connector 9P or USB-B). The optional Infrared Transmitter/Receiver shall be connectable to the BNC jacks on the rear panel. Speech volume control adjusts the microphone volume of the Chairman unit and Delegate Unit shall be located on the front panel. Priority chime volume control adjusts the output volume of the chime tone that sounds when the Priority Speech Key on the Chairman Unit is pressed which shall be located on the rear panel. Power requirement shall be 100-240 VAC, 50/60 Hz, maximum 72 W power consumption (using the provided AC Power Supply) and the operating temperature range shall be 0°C to 40°C (32°F to 104°F). The Central Unit shall weigh 2.8 kg (6.17 lbs) and be constructed of surface-treated steel plate with black metallic paint, semi-gloss finish with dimensions (W x H x D) of 361 x 122.6 x 179.8 mm (14.21" x 4.83" x 7.08" ). The Central Unit shall be the TOA model TS-820RC. The rack mounting bracket shall be the TOA model MB-TS920. The Infrared Transmitter/Receiver shall be the TOA model TS-905 or TS-907.