High-definition television signal converter

摘要

A high-definition signal is band-compressed and is supplied to a simple MUSE processor. The simple MUSE processor generates a simple high- definition television signal. A scanning line processor converts said simple high-definition television signal into an interlaced scanning signal with less scanning lines than the television signal of the present system. The television signal output from the scanning line processor is converted into an analog signal. Two color difference signals, are input to a quadrature modulator which uses a sub-carrier that follows a clock synchronized with the sampling pulse of the high-definition television signal, and is obtained from a synch regenerator. The clock is then input to a phase-locked loop circuit which generates the color sub-carrier, which is phase-synchronized with the clock, and supplies the color sub- carrier to the quadrature modulator. Therefore, the field frequency of the input television signal can be set to invert every frame so long as the field frequency of the input television signal is maintained. The frequency of the color sub-carrier can be draw-in range of a color processor of NTSC system.