RECORDING STATUS DISCRIMINATING CIRCUIT OF VIDEO TAPE

摘要

The circuit for determining video tape recording state in a video set having an A/V signal amplifier, a controller, a microprocessor and a display unit is characterized in that DC converters for smoothing to a DC voltage, A/D converters for converting the DC voltage to a digital code and the microprocessor having a logic operation unit for comparing an output envelope level value with a preset reference value are sequentially connected to image and sound output terminals for outputting image and sound envelope levels of the A/V signal amplifier, image and sound S/W pulse terminals, monostable oscillators and an oscillator are connected to inputs of AND gates, and the control terminals of the A/D converters are connected to the outputs thereof.