TRACKING CONTROLLER OF ROTARY HEAD TYPE MAGNETIC VIDEO RECORDERRREPRODUCER

摘要

PURPOSE:To eliminate the need for control tracks, etc. in a VTR, etc. by using an auxiliary head of a deviated track position. CONSTITUTION:The signals having been reproduced with a playback head H1 turning together with a rotary cylinder 1 and an auxiliary head H2 of the track position deviated by 1/2, etc. of the track width from that of the playback head H1 are passed through amplifiers 7, 11 respectively of an equal amplification degree and envelope detection circuits 9, 12 to become the d.c. voltages equal to the level of the reproduction RF signals. While the head H1 is on-track, the voltage from the circuit 9 becomes higher than the voltage from the circuit 12, and when the output voltage of the circuit 12 is applied to a comparator 10 via an amplifier 13 of twice the amplification degree of the amplifier 7 or 11 and is compared with the output voltage of the circuit 9, then the track position of the head H1 is servo-controlled according to the compared voltage. Hence, the tracking controlling of the VTR, etc. is accomplished without using any control track, control head, etc.