Decatur Electronics G3, User Manual & Installation Manual

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Always use high quality alkaline AAA batteries to power the remote .
Install batteries as shown below . Replace battery cover before
placing remote back into service .
• If the G3 is used in cold weather, the alkaline batteries
may not deliver enough current to drive the IR emitter
properly . In this case, use a high-quality Lithium AAA
rated for low temperature . A recommended battery is:
Energizer L92 Ultimate Lithium
7.0 Communication System Controls
You can configure the G3™ through the serial communications (COM)
port on the rear panel to communicate with PCs, speed signs, and
in-car video systems, such as the Decatur Electronics Responder
1000™ in-car video system . The communications cable does not
come with your order and can be purchased separately from Decatur
Electronics . See Appendix A for the more details on the serial
communications port configuration .
8.0 Performance Tips
Understanding potential radar interference sources and what to do
when they occurs can greatly improve your results .
8.1 How Radar Works
Determining a motor vehicle’s speed begins with the radar antenna
transmitting and directing a beam of microwave energy (radio
waves) at an approaching (or receding) target motor vehicle . When
energy from this beam strikes a moving motor vehicle, a small
amount of the beam is reflected back to the antenna .
The reflected signal frequency shifts by an amount proportional to
the speed of the target motor vehicle . This is known as the Doppler
Effect . The radar device then determines the target motor vehicle
speed from the difference in frequency between the reflected and
transmitted signal .
8.2 Interference Sources and Remedies
When properly installed and operated, Doppler radar technology
is extremely accurate and reliable . However, variations in the
environment can cause situations and circumstances, which
can cause spurious (erratic and unusually low or high) speeds to
display . Signs that a speed is spurious can include the following
characteristics:
• A reading appears when no target motor vehicle is in the
operational range of the antenna .
• A target motor vehicle entering the operational range overrides
the interference signal, causing the display speed to change
suddenly to the motor vehicle’s speed .