Understanding Radar and Laser
Your Detector
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19
Understanding Radar and Laser
Your Detector
18 English
Understanding Radar and Laser
•
Radar Speed Monitoring Systems
Four band frequencies have been approved by the Federal Communications
Commission (FCC) for use by speed monitoring radar equipment:
X band
10.525 GHz
K band
24.150 GHz
Ka band
33.400 – 36.00 GHz
Ku band
13.435 GHz
Your detector detects signals in all four radar bands.
VG-2 and Spectre 1
VG-2 and Spectre 1 are “detector detectors” that work by detecting low-level
signals emitted by most radar detectors. Your detector does not emit signals
that can be detected by VG-2 or Spectre 1, but does detect VG-2 and Spectre 1
signals and will alert you when a device is in use near your vehicle, if you
so choose.
Safety Alert Traffic Warning System
FCC-approved Safety Alert transmitters emit microwave radar signals that
indicate the presence of a safety-related concern. Depending on the frequency
of the signal emitted, it can indicate a speeding emergency vehicle or train,
or a stationary road hazard.
Because these microwave signals are within the K band frequency, most
conventional radar detectors will detect Safety Alert signals as standard
K band radar. Your detector, however, is designed to differentiate between
standard K band and Safety Alert signals, and give separate alerts for each.
Safety Alert technology is relatively new. Safety Alert transmitters can
be found in limited numbers in all 50 states, but the number is growing.
Depending on your location, you may not receive these alerts regularly
and may often encounter emergency vehicles, trains and road hazards
without being alerted. As the number of transmitters increases,
these alerts will become more common.
When you receive such an alert, please watch for emergency vehicles ahead
of you, on cross streets and behind you. If you see an emergency vehicle
approaching, please pull over to the right side of the road and allow it to pass.
Strobe Alert
Special strobes mounted on the light bars of authorized emergency
vehicles (fire trucks, police cars, ambulances) automatically change traffic
signals as the vehicle approaches an intersection. These strobes and the
special strobe detectors located on the traffic signals, introduced fairly
recently by 3M and Tomar, are already in use in more than 1000 cities
nationwide. Cobra’s exclusive Strobe Alert detector will detect these
special strobes and give an emergency vehicle alert.
When you receive such an alert, please watch for an approaching
emergency vehicle and pull over to allow it to pass. To inquire about
coverage in your area, contact your local fire and police departments.
LIDAR (Laser)
The correct name for the technology that most people refer to as
laser is actually LIDAR, which stands for Light Detection and Ranging.
LIDAR operates much like radar. Its signal spreads out like a radar
signal, though not as widely. Unlike radar, LIDAR must have a clear
line of sight to its target vehicle throughout the entire measurement
interval. Obstructions such as sign posts, utility poles, tree branches,
etc., will prevent valid speed measurement.
Some common questions about LIDAR include:
■
Does weather have any affect on LIDAR?
Yes. Rain, snow, smoke, fog, or airborne dust particles will reduce the
effective range of LIDAR and can, if dense enough, prevent its operation.
■
Can LIDAR operate through glass?
Yes. Newer LIDAR guns can obtain readings through most types of glass.
However, the laser pulse also can be received through glass to trigger
an alarm by your detector.
■
Can LIDAR operate while in motion?
No. Because LIDAR operates by line of sight, the person using it cannot
drive the vehicle, aim and operate the gun all at the same time.
■
Is LIDAR legal to use?
Yes. It is legal in all 50 states.
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