Williams Sound Model WIRTX90 User Manual

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Determine Coverage Area
Determine the coverage area needed for the seating area. When using the WIR TX90 transmitter with the RX22-4 receiver, in 
single channel mode, the WIR TX90 can achieve a coverage area of 28,000 ft2 (2,600 m2). In four channel mode, the WIR 
TX90 divides its power among the four signals to achieve a coverage area of 11,000 ft2 (1,022 m2).
NOTE:  The coverage area will vary depending on the sensitivity of the infrared receiver being used. The following 
diagram illustrates coverage area when using a RX22-4, RX15-2, or RX18 receiver with a single WIR TX90 
transmitter in single channel mode.
0
0
-10
-20
-30
-40
-50
-60
-70
-80
-90
10
20
30
40
50
60
70
80
90
10 20 30 40 50 60 70 80 90 100 110 120 130 140 150 160
FEET
FEET
RX22-4 RECEIVER
RX18 RECEIVER
RX15-2 RECEIVER
RECEIVER COVERAGE AREA WITH 
TX9 OR TX90 TRANSMITTER IN 
SINGLE CHANNEL MODE
A136
Figure 2:  Maximum range when using the RX22-4, RX15-2, or RX18 Receiver
These patterns are the direct radiation pattern. The infrared radiation does not drop to zero outside the illustrated patterns; it 
decreases. It still may be useable at a greater distance, depending on the receiver sensitivity and the reflective characteristics of 
the room.
Reflections of the infrared light from walls, ceilings, and floors may change these patterns.
Important: Remember to point the transmitter towards the listening audience!
Remember: opaque objects block infrared light. Thus, the transmitter cannot be concealed behind opaque walls, curtains, etc.
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SoundPlus™ Infrared Listening System
MAN 119H