TESA WS2900C-PRO Operation Manual page 14

Wireless communications are susceptible to interference, distance,
walls and metal barriers. We recommend the following best practices
for trouble free wireless communication.
Electro-Magnetic Interference (EMI). Keep the console several feet
away from computer monitors and TVs.
Radio Frequency Interference (RFI). If you have other 433 MHz
devices and communication is intermittent, try turning off these other
devices for troubleshooting purposes. You may need to relocate the
transmitters or receivers to avoid intermittent communication.
1. Line of Sight Rating. This device is rated at 100 meters line of
sight (no interference, barriers or walls) but typically you will get
50 meters maximum under most real-world installations, which
include passing through barriers or walls.
2. Metal Barriers. Radio frequency will not pass through metal
barriers such as aluminum siding. If you have metal siding,
align the remote and indoor console through a window to get a
clear line of sight.
The following is a table of reception loss vs. the transmission
medium. Each "wall" or obstruction decreases the transmission
range by the factor shown below.
Medium
Glass (untreated)
Plastics
Wood
Brick
Concrete
Metal
RF Signal Strength Reduction
5-15%
10-15%
10-40%
10-40%
40-80%
90-100%
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