| 摘要 |
FIELD: checking devices for vending machines. SUBSTANCE: device has light source, which is connected to controlled direct current power supply, and photodetector, which is connected to threshold circuit, which generates authenticity signal. Device also has additional photodetector and circuit for comparison of its signal against level of signal of reference voltage source. Output of said comparison circuit controls anode current of light source. EFFECT: increased validity of checking. |
