My husband and I recently had to ask our local police department for a letter to verify our good standing in order to adopt. I was embarrassed to find out that we had about a dozen speed warnings between us. If it wasn't bad enough that the chief of police now knows us and our record, the National Institute of Standards and Technology has developed calibrator/simulator units that will certify the accuracy of across-the-road photo radars to Ī1 mph at 65 mph. The unit picks up the radar's continuous wave signal and frequency modulates it at the Doppler rate anticipated for the moving vehicle target. Frequency modulation is achieved using a five-pole microwave switch driven by a digitally-based function generator which is programmed to simulate the Doppler return from vehicles traveling at speeds of 15 to 120 mph (25 to 200 km/h). The units can also be used to calibrate other speed-measuring radars in military and weather forecasting applications. For more information, contact Claude Weil by phone: 303-497-5305 or email: firstname.lastname@example.org.