LTI 20-20 Marksman
Laser Technology, Inc.
IACP approved
Note: European version has a different speed measuring range and different minimum and maximum operating distance.
OPERATION
CONTROLS
DISPLAYS / INDICATORS
Target Speed
0 to 200 mph (0 to 320 kmh)
plus (+) for approaching, minus (-) for receding targets
accuracy: +/- 1 mph
or
Target Range
30 to 3,500 feet (9 to 1067 meters) -- late 1990's models.
30 to 1,000-2,000 feet (9 to 300-600 meters) -- early 1990's models.
accuracy: +/- 6 inches
ERROR MESSAGES
Measurement error
Timing error
System error
other errors
not all versions have all error messages
E01 -- target never acquired. The target was out of range or was too close.
E02 -- insufficient data. The instrument's view was obstructed or the target moved out of range.
E03 -- unstable targeting. Caused by poor aiming or by panning off the target
E07 -- optical interference detected. Indicates the possible use of a laser jamming device. Accompanied by a warble tone.
E04 -- the instrument did not have enough time to determine the speed. Minimum time is 1 second.
E05 -- the instrument had too much time to determine the speed. The maximum time is 99.99 seconds
E50, 51, 54 -- self-calibration failure. The instrument detected a problem during self calibration. Contact manufacturer.
E52, 53 -- temperature failure. The instrument is being operated outside its recommended operating temperature range.
E60, 61, 62, 63 -- memory failure. The instrument's electronucs may have been tampered with. Contact manufacturer.
E70 -- key activated. A function key was pressed during power-up sequence. Power off, then on again.
do -- Display overflow. The number to be displayed exceeds the display capacity.
lo b -- Low battery. The Instrument's supply voltage level is
insufficient.
EUROPEAN VERSION
TARGET SPEED
0 to 155 mph (0 to 250 kmh)
accuracy: +/- 1 mph up to 60 mph, 3 percent over 60 mph
TARGET RANGE (stationary target)
65 to 1,300 feet (20 to 400 meters)
SPECIFICATIONS
The unit is programmable, some specifications and features, such as speed/range in English or metric units (mph/ft or kmh/m) are a function of software version installed.
Manufacturer claims unit processes a target if more than 75 percent (45 out of 60 pulses for US version) of target echoes during one sample period (0.3 second) are valid. Valid echoes must be within 20 centimeters (about 8 inches) of expected range (about 1.3 nanoseconds).
speed range +/-200 mph (on-coming and going traffic) speed accuracy +/-1 mph velocity sample time 0.3 seconds target range 30 feet (min) to 1,000 or 2,000 feet range accuracy +/- 0.5 feet (6 in) range (claimed) beamwidth 3.5 mrad (0.2 degrees) early models 3 mrad (0.172 degrees) aperture separate transmit / receive transmit above receive aperture wavelength approx 904 nm pulse rise/fall less than 1 ns light source 3 diodes lined up side-by-side environmental -22 to 140 degrees Fahrenheit (-30 to 60 degrees Celsius) dimensions 3.5 x 5 x 8 inches weight 4.5 lb Data Output serial data for still or video camera LASER PULSES reported (best guess) 60 pulses per sample time 200 pulses per second (sample time 300 ms) 125 pulses per second (European version) pulse width 12 ns pulse width