Discriminating method of tape traveling speed

Abstract

Abstract PURPOSE:To discriminate tape speeds with simple circuit constitution without using any control signal by discriminating the tape speed in the stage of recording by the average value of the output levels of the RF signals reproduced with a rotary video head. CONSTITUTION:The signals reproduced with a rotary video head 4 are inputted to a head amplifier 6, and are restored as reproduced image signals. On the other hand, the reproduced RF signal (b) is inputted to a detecting rectifier circuit 9 which outputs the voltage (e) corresponding to the envelope. A low- pass filter 10 smooths the signal (c) and outputs the voltage (e) of approximately the DC equal to the average level of the signal (c). A threshold forming circuit 12 divides the voltage which is held of peaks with resistors R1, R2, whereby the voltage Vs is obtained. A voltage comparator 13 compares the averaged voltages (e) and Vs and outputs a ''High level'' when the tape traveling speed in the stage of recording differs from the speed in the stage of recording and outputs a ''Low'' level when the speeds are the same.

Inventors

• 👤 Kanji Kubo
• 👤 久保　観治
• 👤 Mitsunobu Furumoto
• 👤 古本　光信
• 👤 Yasuo Nishitani
• 👤 西谷　康夫
• 👤 Hiroshi Taniguchi
• 👤 谷口　宏

Bibliographic Details