The sweep frequency is the line and frame rate of tube monitors.
The images are usually written line-by-line on picture tubes. The horizontal deflection frequency is the number of lines written per unit of time. The vertical deflection frequency is the number of images per time unit.
Within television sets with picture tubes, a tilting part with the horizontal and vertical deflection frequency is required, the output of which is routed to deflection coils on the picture tube.
In Europe, the line frequency is 15.625 Hz, the vertical deflection frequency is 50 Hz. The line jumping process transmits each image as two fields so that the image frequency is only 25 Hz. This requires only the transmission of 25 images, but the eye is presented with 50 half images, which greatly reduces the flicker. The method halves the required transmission bandwidth with similar quality. Edit source text
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