The bowtie test signal actually consists of three signals, each being fed to a different channel of the CAV system and is used to evaluate the relative amplitudes and relative timing on some CAV waveform monitors such as the WFM300A. The figure below shows the three waveforms in the parade mode. The first signal is a 500 kHz sinewave packet which is fed to video channel 1. The other two signals are identical 502 kHz. The three sinewave packets are generated to be precisely in phase at their centers. Because of their 2 kHz offset, the color difference channels become increasingly out of phase with the luminance channel on either side of center. If the three signals are properly timed, their sum results in the bowtie waveform shown below.