GB1358766A - Colour television signal recording and reproducing system - Google Patents

Abstract

1358766 Recording colour television signals MATSUSHITA ELECTRIC INDUSTRIAL CO Ltd 8 Sept 1971 [9 Sept 1970 (2) 14 Sept 1970 (2)] 41895/71 Heading H4F A colour television signal is recorded on monochrome film by combining the luminance and two chrominance signals in frequency multiplex manner, at least one chrominance signal being amplitude-modulated on a subcarrier and the subcarrier being suppressed. As shown in Fig. 2 the I signal is so modulated on to a 1À25 MHz subcarrier, the Q signal is unmodulated, and the luminance signal is amplitude-modulated on to a 5 MHz subcarrier in vestigial sideband form, the integral relationship between subcarrier frequencies enabling the recovery of the 1À25 MHz subcarrier from the luminance subcarrier. Such an arrangement is stated to eliminate interference effects on the luminance signal due to harmonics of the colour subcarrier. In a modification of this arrangement (Fig. 4, not shown) the I and Q signals are combined in phase quadrature to modulate the 1À25 MHz subcarrier. Other similar arrangements with subcarrier frequencies so chosen as to facilitate the recovery of a colour signal to NTSC standards are described. In all these arrangements one colour frame is recorded on one film frame by the synchronized scanning thereof.