What i want to accomplish is to detect video to see if a commercual ad was played or not. No specific ad just need to know if there was an absense of video when the video ad should have played. This is for a tv broadcast station use. As it is now the only way to know is to go back and review the recording. A light should come on for the master control operator to see. I am looking for ideas and info on this. I am limited on my knowledge but one idea i have is to use a digital tv converter box for analog tv. Use the composite video to see if there is any video. Design a detection circuit, then use an arduino circuit as data logger to flash an led, to record the time of incident and to visually show the time of the incident. The led and circuit can be reset at any time manually. As a note here the tv station is broadcasting in digital not analog. I am here in the U.S. so using 8vsb scheme. Also there are up to 7 channels of video to detect from just one station frequency. This station operates more than one channel frequency, like channel 12 and channel 38 as an example, but keep in mind there can be 7 subchannels for each. If there was a way to step through these with one device it would be better. but a light is needed for each subchannel.like tv station channel 12.1,12.2, 12.3 etc so the master control operator knows which channel did not play the ad. For clarification, if the ad doesnt play they cant charge the customer for that ad spot. So any help or ideas are greatly appreciated. Thanks