Abstract: An automatic timing and scoring system equips vehicles with transmitters and places the receiving antenna on the track used by the vehicles. Each vehicle transmitter has a unique frequency. The receiving antenna is located so that the transmitters pass adjacent thereto. The receiving antenna is coupled to a receiver. The receiver has an amplifier and bandpass filters. The bandpass filters pass all of the transmitter frequencies, while rejecting much of the noise. The signal that is received by the receiving antennas is amplified and then limited to a predetermined amplitude. Then, the received signal is shifted in frequency to an intermediate frequency. The intermediate frequency signal is passed through a narrow bandpass filter that rejects all transmitter frequencies but the transmitter frequency of interest. Then, the intermediate frequency signal goes to a tone decoder, which detects signals having predetermined minimum durations.