Tape recording system for broadcast video signals - provides wide bandwidth luminance and chrominance signals without increase in tape speed using linear circuits

摘要

The received signal from an aerial tuner (1) is filtered (41) and fed via an automatic gain control circuit (3) to a circuit (42) where it is mixed with a 33.15 MHz local oscillation. After sound signal separation (44), the mixed signal is fed via another bandpass filter (45) and linear pre-emphasising circuit (46) to a circuit (47) which subtracts the 5.75 MHz signal component. The resultant signal is then added (48) to a 5.75 MHz signal, 90 deg. out of phase with the first, before being amplified (16) and recorded (17,18). On playback, the processess is reversed, with the 90 deg. 5.75 MHz component being subtracted and the 0 deg. 5.75 MHz signal being re-instated.