WHAT TIME IS GREEN ?
In color television, the colors on the screen are determined in a special way. A reference signal is sent and then the color signals are matched against it. For example, when the second signal is out of step by 50-billionths of a second, the color is green; 130-billionths means blue. For colors to b e true, the timing must be exact. An error of unbelievably small size can throw the entire picture off color. A delay of only a few billionths of a second can make a yellow dress appear green or a pale complexion look red.
BELL TELEPHONE
To ready the Bell System's television network for color transmission, scientists at Bell Telephone Laboratories developed equipment which measures wave delay to one-billionth of a second. If the waves are off, as they wing their way across the country, they are corrected by equalizers placed at key points on the circuit. This important contribution to color television is another example of t h e pioneer work done by Bell Telephone Laboratories to give America the finest communications in the world.
To keep colors true in television, signals must be kept on one of the world's strictest timetables. Equalizers t h a t correct offschedule waves are put into place at main repeater stations of the transcontinental radio-relay system.
LABORATORIES
IMPROVING TELEPHONE SERVICE FOR AMERICA PROVIDES CAREERS FOR CREATIVE MEN IN SCIENTIFIC AND TECHNICAL FIELDS.
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