Abstract: In a color television signal the total line length or period and the bandwidth requirement can be conventional, but the active line period is increased to e.g. about 94% of the line period, giving an aspect ratio of about 3:2 instead of 4:3.

Abstract: In a color television system the luminance signal is split into high and low frequency components, and the high-frequency luminance components are frequency shifted to above the conventional television bandwidth. A conventional receiver uses the low-frequency luminance components (Y.sub.1) and the chrominance component (C), with no cross effects between them. A high-quality receiver can be constructed to recombine the low-frequency and high-frequency luminance components (Y.sub.1 and Y.sub.2 ') giving improved luminance detail, again without cross effects with the chrominance signal. The sound signal (S) is carried between the chrominance and high-frequency luminance. A transmitter (FIG. 4) and receiver (FIG. 5) are described. The system has particular applicability to satellite and cable television.