Travel detector of recording medium

Abstract

Abstract PURPOSE:To detect a tape travel speed in case of a control system which records pilot signal of cyclically varying frequency on every track by generating a travel detection signal on the basis of waviness occurring to a reproduction tracking error signal. CONSTITUTION:The pilot signal detecting circuit 32 of a helical scan VTR, etc., detects the pilot signals of different frequencies recorded cyclically on respective tracks for tracking control, and the error signal generating circuit 3 generates a tracking error signal S3 for the frequency difference between the reproduction pilot signals. This signal is applied to a detecting circuit 32 for the number of a waviness period which performs a positive feedback Schmitt amplification, etc.; when the signal S3 exceeds a threshold value, a rising detection pulse S5 is generated in every waviness period of a signal S2. Then, pulses S5 are integrated by an arithmetic circuit 33 to detect securely a travel speed in a quick traversing mode, etc., on the basis of the waviness of period corresponding to the travel speed even in case of this tracking control system.

Inventors

• 👤 Shoji Nemoto
• 👤 根本　章二
• 👤 Hiroshi Yoshioka
• 👤 浩 吉岡

Bibliographic Details