| 摘要 |
<p>PURPOSE:To reduce the number of UP/DOWN switches only to a pair by providing a tracking circuit with a limiter for connecting counters strong a normal reproducing delay time and a slow reproducing delay time respectively and an UP/DOWN switch selectively to a counter. CONSTITUTION:A signal is sent from a remote control decoder 31 to OR gates G1-G4. When a system controller 17 outputs a signal F1 by a signal outputted from the gate G3, the limiter 19 is connected, the output of the gate G1 is transmitted to a counter 3a and the output 23 of the counter 3a is inputted to a normal reproducing monostable multivibrator 8a through a switching device 22, a D/A converter and contacts Sc-Sa of a switch 22. A tracking delay time is determined by the contents of the counter 3a. The D/A converter 5 consists of an analog switch S and a divided resistor R and the counter 3 generates a signal of 5 bits by a preset value 4 and the selection of the switches 1, 2, shorts the divided resistor selectively, changes a time constant, and changes the delay time of the monostable multivibrator 8. In such constitution, it is unnecessary to prepare two pairs of tracking adjusting means such as UP/ DOWN counters.</p> |
