Never Buy Another Radar Gun. The Sensor-1 GPS Speed Sensor is a completely self contained GPS unit in a plastic. The Sensor-1 Speed Sensor has an integrated magnetic mount for ease of installation. You can customize your Speed Sensor with connectors for Raven, Tee-Jet, DICKEY-john, John Deere and many other brands of Monitors and Tractors. The Sensor-1 Speed Sensor features a Radar Pulse of 57 Hz for most applications and comes standard with a 15 foot lead wire.