
Our reader Andrea (andrea[dot]perugia[-at-]gmail[dot] com) sent his circuit to us, and he creates the circuit for educational intent. The main purpose is to show that you can toggle an output state electronically, although physically you use only a push button switch. Here is what he said about the cicuit : This simple [...]
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As the price of security camera going down, installing the camera in the shop, office, or even in home becomes economically feasible. Providing a dedicated monitor for every installed camera is not efficient, and your CRT monitor might suffer phosphor burn if it used to display static image from only one camera. To display 1, [...]
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This circuit is not a voice operated switch (VOX) because this circuit is too dumb to differentiate between musical sound or human voice. This is rather a sound activated than voice activated. One interesting application is to control your disco lighting automatically by the musical sound from high power amplifier, when the music signal is [...]
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This circuit is similar with our previous dimmer circuit, but the gate control is full-wave rectified using diode bridge. This circuit can be used to replace electric switch for your incandescent lamp, brushed motor, soldering iron or heater. Here is the schematic diagram of the dimmer switch: Please note that his dimmer switch [...]
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To avoid exceeding luminance reference level standard or to avoid exceeding the input range of digitizer (ADC), video signal is often needed to be limited. The simple way to do this is by hard limiting the signal in the positive direction (white peak clipping), but this method completely destroy all information contained in the clipped [...]
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This is a circuit of differential analog switch. This circuit uses the FM1208 monolithic dual. Here is the circuit: This circuit is ideal choice for an accurate multiplexer because RDS (on) for the monolithic dual tracks at better than ± 1% over wide temperature ranges (-25 to +125°) although it is unusual. [...]
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