21. It consists of a video signal with a blacked-out picture. 22. Its output was 10 frames per second at 100 lines per frame video signal . 23. However, this no longer works when S-Video signals are used. 24. The recording on the metal tape was a mirror image of the video signal . 25. However, little equipment has actually been produced that outputs a SECAM analogue video signal . 26. A video codec accomplishes the same task for video signals . 27. Video signal generators are primarily classed according to their function.28. C-Cube makes chips that translate digital video signals from satellite broadcast into television images. 29. These lines are typically inserted into the vertical blanking interval of the video signal . 30. This signal is then amplified and inverted, and then represents a positive video signal .