Which is NOT a factor that may affect radar operation?

The speed of the patrol car is not a factor that affects radar operation in terms of how the radar itself functions. Radar operates using radio waves that measure the speed of a moving object against a stationary reference point. The operational effectiveness of radar systems is influenced by the environment, including physical obstructions and reflective surfaces, but not by the speed of the vehicle conducting the measurement.

In contrast, reflective signs, electric power lines, and microwave towers can all impact radar operation because they can cause false readings or interference. Reflective signs might bounce radar signals back in such a way as to confuse the radar unit. Electric power lines can radiate electromagnetic interference that could distort readings, and microwave towers may cause similar interference due to their own transmission signals. These environmental factors directly affect the accuracy and reliability of the radar system, whereas the speed of the patrol car itself does not alter how the radar measures speed.