Digital tachometer (CB7376E)

Found in Radio Electronics from the 90s, this circuit uses components from that time. However, it can still be elaborated with some ease.

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The figure shows how to control the blinking of a 5 V blinking LED with an LDR. The LED only...
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Suggested by Maxim in documentation from the 90s, this circuit has its response curve given next to...
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