Operation
Power up
When the Ranger EZ is first turned on, it will go through a complete self test. The radar will first perform a light
test, in which all of the display's indicators will light, and then the radar will perform a 32 mph internal circuitry
test. After the self-test, the current software version will be shown, followed by the current antenna configuration.
The front antenna type will be displayed, followed by the rear antenna type: “2” for a K band antenna and “0” for
no antenna.
Tuning fork tests in general
A tuning fork test is the standard test for proving that the antenna and counting unit are functioning properly. In
older analog radars, the dual tuning fork tests actually checked two different circuits, one each for patrol and
target speeds. However, the Ranger EZ uses a single circuit, the digital signal processor (DSP), to determine both
speeds, so that testing the Ranger EZ with a single tuning fork in stationary mode actually ensures that the entire
radar is working. Despite this fact, MPH recommends that you follow your court-proven department guidelines
for performing tuning fork checks.
Since the Ranger EZ is a directional radar and the tines of a tuning fork vibrate in both directions, tuning fork
tests are more complicated than they are with non-directional radars. Therefore, the Ranger EZ has a Tuning Fork
Mode, which is used while testing the radar with tuning forks. In this mode, the Ranger EZ works as a non-
directional radar, allowing the tuning forks to work properly.
Placing the Ranger EZ in Tuning Fork Mode
When a self test is performed on the Ranger EZ by pressing the Test button on the remote control, the radar does a
segment check and a 32 mph test. After this, the radar displays an “F” in the hundreds digit of the Target
window. This indicates that the radar is in Tuning Fork mode. The radar will stay in Tuning Fork mode for 30
seconds after the self test is complete.
To place the radar in Tuning fork mode for an extended period of time, press the 2
nd
F button on the remote
control and then the Fork button. The radar will remain in Tuning Fork mode until it is manually taken out of
Tuning Fork mode by pressing 2
nd
F followed by the Test button. You may need to do this to fully test the radar.
Stationary mode tuning fork tests
To perform a stationary mode tuning fork test, place the radar in Tuning Fork mode and strike the tuning fork on
wood or plastic and hold the ringing fork in a fixed position two or three inches in front of the antenna with the
narrow edge of the fork facing the antenna front. This will cause the target speed window to display the speed
labeled on the fork (+ 1 mph). While performing the tuning fork test, the audio volume level may be set to a
desirable level.
Fastest mode may be tested by using the lower speed tuning fork as above and by placing the ringing higher speed
fork into the antenna beam at a greater distance since the fastest target should be a weaker signal than the target.
The Fastest button must be pressed and held on the remote. The audio will switch to the fastest target when
present. For example, for forks marked 35 mph and 65 mph, the target would read 35 (the closer fork) and the
fastest window would read 65.
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