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Out’ and the alert will finish. If the unit ‘Times Out’ and you then approach the
next camera in the SPECs series however, the unit will alert you to that
location at your preset alert distance.
When you have passed the last camera in the series the display will indicate
‘SPECs End’.
Please Note:
If you join a road in the middle of a SPECs series you will
automatically get a visual and audible alert, 250m before the first camera that
you pass.
If you would like to change the alert to a visual alert only press the
MUTE/CANCEL button to temporarily turn off the sound. If at any time you
would like to stop the alert, simply press and hold the MUTE/CANCEL button.
Laser Alerts
The Snooper Evolution incorporates a built-in laser detector. As laser often
requires instant action the device simply gives you an audible or voice alert
whilst the display will flash ‘Laser’.
As GPS is not used to locate laser, it is impossible to indicate the speed limit
or count down accurately the distance to a location in metres during a laser
alert.
If you would like to change the alert to a visual alert only press the
MUTE/CANCEL button to temporarily turn off the sound. If at any time you
would like to stop the alert, simply press and hold the MUTE/CANCEL button.
How Laser works
LASER stands for Light Amplification by Stimulated Emission of Radiation
The laser speed gun uses a method that relies on the reflection time of light.
You have probably experienced the reflection time of sound waves in the form
of an echo. For example, if you shout down a well or across a canyon, the
sound takes a noticeable amount of time to reach the bottom of the well and
travel back to your ear. Sound travels at approximately 1,000 feet (300
meters) per second, so a deep well or a wide canyon creates a very apparent
round-trip time for the sound.
A laser speed gun measures the round-trip time for light to reach a car and
reflect back. Light from a laser speed gun moves a lot faster than sound --
about 984,000,000 feet per second (300,000,000 meters) or roughly 1 foot
(30 cm) per nanosecond. A laser speed gun shoots a very short burst of
infrared laser light and then waits for it to reflect off the vehicle. The gun
counts the number of nanoseconds it takes for the round trip, and by dividing
by 2 it can calculate the distance to the car. If the gun takes 1,000 samples
per second, it can compare the change in distance between samples and
calculate the speed of the car. By taking several hundred samples over the
course of a third of a second or so, the accuracy can be very high.
Operating Instructions
Operating Instructions
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