COLOR TELEVISION RECEIVER

• Main Authors: SUGIHARA Y,JA, HORAGUCHI A,JA
• Format: Patent
• Language: English
• Published: 01.05.1973
• Subjects: ELECTRIC COMMUNICATION TECHNIQUE; ELECTRICITY; PICTORIAL COMMUNICATION, e.g. TELEVISION

A color television receiver for use in a transmission system such as PAL system in which a pair of color signals provides quadrature balanced modulation of a color subcarrier simultaneously with respect to mutually orthogonal modulation axes with one of the axes being reversed by 180 DEG for alternate horizontal scanning lines and in which the resulting color television signal contains a color burst signal capable of providing distinction of the polarity of the color subcarrier that is phase alternating, the receiver using two reference subcarriers indicating the demodulation axes during demodulation of the chrominance signal, one of said reference subcarriers reverting its phase in consecutive horizontal scanning lines by 180 DEG in correspondence to the respective modulation axis, characterized in that for generating the reference subcarrier having an alternating phase a subcarrier of a frequency of fsc+/-(2n - 1)/2 fH is generated, where fsc denotes the color subcarrier frequency, fH the horizontal scanning frequency and n a positive integer, and this subcarrier is so modulated in a phase modulating means with a sawtooth wave of horizontal scanning frequency that its phase during each line keeps constant relative to the other reference subcarrier.