BOWLING GREEN v. BAMMER

JAMES W. BACHMAN, Judge.

Complainant, Patrolman Dan Adams, has charged defendant, Corey H. Bammer, with speed unreasonable for conditions (49 m.p.h. in a 35 m.p.h. zone), on Sunday, August 25, 1991, at 7:55 p.m., eastbound on East Wooster Street at the I-75 overpass in the city of Bowling Green, Wood County, Ohio, this being an alleged third moving violation within the last one year.

On October 11, Bammer filed a motion to dismiss the charge on the basis that the traffic speed radar device used by Adams (the "Stalker") is not a reliable device to determine accurately the speed of a target vehicle moving toward the complainant's patrol car. The court has also deemed that motion to be one objecting to the prosecution's intention to use as evidence the readout from the Stalker traffic speed radar device.

On October 18, 1991, the court heard evidence on the motion, concluded that it was not well taken, and overruled the motion. Thus, the court concluded that the Stalker was a reliable radar device for determining the speed of a vehicle moving on the roadway. Now the court renders a written decision on that ruling.

The prosecution presented the testimony of John L. Aker, a representative of Applied Concepts Marketing, Inc., the company that manufactures and markets the Stalker. Aker has a Bachelor of Science degree in electrical engineering from the University of Louisville in 1962. He was chief engineer and vice president of Custom Electronics, a major supplier of police radar units. He holds two patents on police radar inventions. In about 1987 he began working with Applied Concepts to develop a new radar unit, which was the Stalker gun; he wrote the software program for the Stalker. The prosecution also filed the operations manual and related documents.

The Stalker is a speed measuring Doppler radar device. It provides all of the features found in conventional speed detection radars; however, it operates on channels different from those radars, namely, it operates on channels in the Ka band ("K sub-a band"), rather than X band radar and K band radar. As a result, current 3-band radar detectors cannot detect the Stalker's operation, even when the Stalker is transmitting continuously, because they are not currently operating in that band.

Stalker is FCC (Federal Communications Commission) approved for operation over a range of Ka band frequencies (channels), whereas X band and K band radars must operate on one specific channel. Therefore, Stalker's Ka band frequency operation provides the flexibility to counteract even future improvements in radar detectors.

The device provides a standby (or hold) mode which reduces the possibility of detection by radar detectors. More significantly, it also operates in the Ka band from 34.2 to 35.2 GHz, which most radar detectors do not receive.

Stalker uses a state-of-the-art digital signal processor computer chip to process the Doppler signal and control all other functions (that technology is closely related to what is used in computer disc players, and provides similar improved performance). The older radar units ( e.g., K 55 radar and S 80 radar) use analogue signal processing. The advantage of digital signal processing is that it is not subject to temperature variations or variations in time due to component aging.

All of the "smarts" of Stalker are contained in a plug-in software chip that controls the digital signal processor. The plug-in chip is easily changed. Accordingly, as radar detector technology advances, Stalker can be readily upgraded to stay ahead of that technology.

The Stalker comes in two models: the stationary model (patrol car not moving) and the moving model (patrol car moving).

The Stalker is designed to conform to NHTSA (National Highway Traffic Safety Administration) minimum performance specifications.

A few hours of instruction normally are enough to qualify an officer as an operator of the Stalker. The operator need not understand the scientific principles of radar or be able to explain the inner workings of the radar unit. It is sufficient, to qualify as an operator, that the officer has sufficient knowledge from training and experience to set up, test, and read the Stalker.

Before the officer uses the Stalker on any given day, there are three tests to determine if the unit is operating properly: power-on self-testing; internal circuit test; and tuning fork test. Also, there is an optional moving-vehicle test.

Each time the officer powers on the Stalker, it automatically self-tests to verify that the unit is functioning properly as shown by the display indicating "888 888." If the unit is not functioning properly it displays "fail."

Secondly, the officer then performs an internal circuit test by pressing the test key, which causes the unit to transmit briefly. This checks the transmitter frequency against an internal reference. This also checks the two internal time bases against another to verify the accuracy of time intervals used in speed measurement. The LCD indicator will show either "test okay" or "test fail."

If all test parameters are correct, the target display will indicate a speed of "40." The manufacturer recommends that the officer do this internal circuit test daily before using the device, and when the officer discontinues use of the device.

Lastly, the officer performs a tuning fork test, by striking a 40-mile-per-hour tuning fork against a hard non-metallic surface and then quickly holding it in front of the antenna end of the unit. The target speed should display 40 miles per hour, plus or minus 1 mile per hour ( i.e., 39 m.p.h. or 41 m.p.h.). The manufacturer recommends that the officer do this tuning fork check daily before using the device and when the officer discontinues use of the device.

There is an additional optional test, called the "moving vehicle test," but it is not a substitute for the tuning fork test. While driving the patrol vehicle with an accurately calibrated speedometer, the officer aims the unit down an empty roadway directly in front of the vehicle. The speed indicated by Stalker should match the speedometer indication to within a small error (depending on the speedometer accuracy).

Generally, the Stalker operates like any other speed radar device. The officer simply aims the unit at the target and pulls the trigger and an "XMT" indicator appears on the radar unit's display — indicating that a radar signal is being transmitted.

If the target is in range, an LED readout of the target speed will appear in the unit's target-speed window. Also, a Doppler audio tone will be heard on the speaker. The audio tone will be proportional to the target speed. The Stalker will continually measure the target speed and will continually emit a Doppler audio tone as long as the trigger is pressed and the target is present. When the officer releases the trigger, the last reading obtained will be retained on the display until the officer presses the trigger again. The unit transmits while the trigger is pressed and switches to standby (hold) when it is released. In the standby mode no signal is transmitted.

At any time either while transmitting or in standby, the officer may lock in the target speed in the "lock speed" window on the right half of the display. He does this by pressing the lock key. Doing this will have no effect on the target-speed display, which will continue to function as before, showing the present target speed.

Whenever the officer is tracking a target, a Doppler audio tone will be heard from the speaker. The pitch of the tone indicates target speed, while the tone quality is useful for judging possible interfering or multiple targets.

The officer's estimate of excessive speed (from visual observation), when confirmed by the reading of the radar device and when the suspect vehicle is out front, by itself, nearest the unit, is sufficient to identify the vehicle, if the officer's visual observations support the radar evidence.

The Stalker, like any other traffic speed radar device, is subject to a variety of interference sources — both natural and man-made — such as terrain, rain, electrical noise, moving objects inside the vehicle, interference from other transmitters, and power supply. However, a trained and observant officer will note those symptoms and take the appropriate steps to avoid the cause of the problem or to ignore misleading indications.

So, in conclusion, the court had decided that the Stalker is a reliable device for accurately determining the speed of a target vehicle moving toward the patrol car. Accordingly, the court has overruled the defendant's motion to dismiss and motion objecting to prosecution's intention to use evidence.

Motions dismissed.