Free Simple Circuit Diagram
This is a Peak Voltmeter circuit. This circuit can be viewed as a pulse stretcher, which catch fast pulse signal to be measured by a slow response voltmeter. Even a fast response meter need this circuit since our visual perception won’t be able to catch a fast event. Here is the schematic diagram of the circuit: This circuit is used […]
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This is a simple Electronic thermometer circuit. This is a inexpensive circuit because probe or sensor that is used in this circuit is 2N2222 silicon transistor. The accuracy of this circuit is better than 1°C over a 100°C range. The input voltage of this circuit is regulated to 1.2V by the LM113 diode. This voltage is used to set operating […]
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A pulse counter can be built by using 7490 decode counter and 7557A. This circuit can count from zero to 9. Pins 3 and 2 of all 7490’s must be connected together. Here is the schematic diagram of the circuit: A push button is used as reset. The input of this circuit is a pulse that is produced by other […]
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Very simple light meter can be constructed using LDR (light dependent resistor) wired in series with a battery, variable resistor, and ampere meter. Here is the schematic diagram of the circuit: The ampere meter is a 100 uA analog meter. Don’t expect too much about the linearity, absolutely can’t be compared to standard light intensity meter which measure luminosity in […]
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