If the photograph is clicked, it grows.

TTL CMOS DTL Logic Checker for 5V only 14pin or 16pin switchable by side button LED lit 1 or Open LED dark 0 Max +8V Supply Operating 5V +-0.5V current Max 60mA Threshold 1.0-2.0V Input current 10uA max(+3.5V) -200uA max (+0.5V) Do not use CMOS 15V logic

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