Free Simple Circuit Diagram
A vibration meter circuit shown in the following schematic diagram uses LM3915 a the main active component. This vibration meter uses a piezoelectric transducer to pick up the vibration. The logarithmic characteristic of LM3915 make this meter circuit works for wide range measurement, suitable for measuring engine block vibration or other system where the dynamics is wide. Here is the […]
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Providing a touch switch can be a cool way to make your circuit looks sophisticated. Moreover, providing separate touch pad for “on” and “off” function improve the safety, since touching one function doesn’t trigger opposite action to what we expect even at wrong assumption about current state. Here is the schematic diagram of the circuit: How this circuit works is […]
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Frequency modulation (FM) can be used to transmit analog voltage level signal with good noise immunity. The transmission itself might employs different methods, and this circuit uses free air optical medium. This optical receiver circuit is built using a L14G2 detector, two stages of gain, and a FM demodulator. To obtain better sensitivity, we can use more stages of stabilized […]
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Configured with capacitive coupling (by inserting a small cap between photo-transistor and bipolar transistor), this relay circuit will respond only to rapid changes in light while ignoring normal gradual changes in ambient light. Rapid changes can be produced by light interruption or turning on/off lamps, while gradual light changes can be produced by clouds or sunrise. Here is the schematic […]
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