What is the purpose of the tuning fork test for radar?

The tuning fork test for radar is specifically designed to ensure that the radar system operates accurately by confirming that it works within 1 mph of the indicated speed. The test involves using a tuning fork that vibrates at a specific frequency corresponding to a known speed; when introduced to the radar, it allows the user to check if the indicated speed aligns closely with the actual speed of the tuning fork's frequency. This is crucial for validating that the radar is functioning correctly and is calibrated properly, as any significant deviation could lead to inaccurate speed readings and ultimately impact enforcement actions.

While the other options may seem plausible in a broader context, they do not accurately capture the primary aim of the tuning fork test. The tuning fork's role is not about measuring general speed or assessing compatibility with vehicles, nor does it evaluate the power output of the radar unit. Its focused purpose on ensuring accuracy within a narrow margin of error is foundational for reliable speed enforcement.