Improvements in Color Television Studio Video System Performance

Frank Davidoff

Signal sources such as Plumbicon live cameras, 4-channel vidicon film cameras and high-band video-tape machines provide very high quality inputs to today's color television broadcasting studios. To satisfy the needs of TV program procedures, the studio facilities have been made extremely complex. For example, studios in the CBS Broadcast Center in New York contain three cascaded video-fader and/or special effects generator units to satisfy unusual production situations. Depending on the particular path through the studio, a video signal will normally pass through at least seven or as many as fifteen different amplifiers. Also the studio must present the same electrical length to the color subcarrier regardless of the path taken by the signal. The above factors made it difficult to achieve the high quality color studio performance which is necessary to avoid deterioration of the input signals. One of the most serious problems has been a dip or saddle in the amplitude-frequency response between 1 and 4.2 MHz; another has been a midfrequency (15.7 kHz) smear. After discussion of the solutions to these problems, there are described special techniques developed to make amplitude-frequency response measurements to better than 0.05 dB and to detect midfrequency smears in the order of 1 mV peak-to-peak amplitude.

Print ISSN
Published
1967-08
Content type
Original Research
DOI
10.5594/J09121