M P H Industries Inc SDRRK02 ユーザーズマニュアル

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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. 
 
Moving mode tuning fork tests 
 
Moving radar units are designed to acquire a patrol speed and look for target speeds that are faster 
(opposite direction) or slower (same direction) than the patrol speed.  These two speeds can be 
simulated using tuning forks.  The two forks are manufactured to vibrate at different frequencies.  
One fork will be used to simulate patrol speed and the other target speed.  In moving mode, the 
speed printed on the target fork will not match the speed shown on the RANGER display.  It will 
be added to or subtracted from the patrol speed depending on the mode switch selections. 
 
 
For opposite direction moving mode, the lower speed fork will simulate patrol speed while the 
higher speed fork will represent the target.  For same direction moving mode, the higher speed fork 
will be the patrol while the lower speed fork will be the target. 
 
 
To perform the tuning fork test, place the radar in Tuning Fork mode and strike the patrol fork 
(lower frequency) on a hard nonmetallic surface.  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.  The speed 
will be shown in the patrol window.  While continuing to hold the ringing fork in place, strike the 
other fork and hold it next to the patrol speed fork.  Both forks must be vibrating while being held 
an approximately equal distance from the antenna.   
 
For opposite direction moving mode, the radar should display the low speed fork as patrol and the 
difference between the forks as the target speed.  For example, for forks marked 35 mph and 65 
mph, the patrol would read 35 (low speed fork) and the target would read 30 (high-speed fork 
minus low speed fork). 
 
Testing the same direction moving mode with tuning forks is a little more difficult.  The radar will 
display the high-speed fork as the patrol speed.  However, since a tuning fork vibrates in both 
directions, the unit cannot determine whether it should add or subtract the low speed fork from the 
high speed fork.  Therefore, Tuning Fork mode turns off the direction sensing of the radar and 
allows you to tell the radar whether to treat the target fork as approaching or receding. 
 
To accomplish this, the Fastest button on the remote control is used.  In Tuning Fork mode, the 
RANGER assumes that the target is moving faster than the patrol speed.  Therefore, with forks 
marked 35 mph and 65 mph, the patrol would read 65 (high speed fork) and the target would read 
100 (high-speed fork plus low speed fork).  To test the other case, when the target speed is slower 
than the patrol speed, press the Fastest button.  This makes the radar momentarily subtract the 
target speed from the patrol speed.  With forks marked 35 mph and 65 mph, the patrol would read 
65 (high speed fork) and the target would read 30 (high-speed fork minus low speed fork).