Free Simple Circuit Diagram
The circuit below is configured as a comparator. A fixed reference voltage at the non inverting input is provided by R1 and R2. The inverting input voltage is set by the other two resistor. The output goes to minus 12 volts and the buzzer is energized if the voltage at the inverting input rises above the reference voltage. By swapping […]
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Good/Bad transistor tester means that this instrument can only determine if the transistor is good or bad, nothing more. Any transistor with gain equal to 30 or more will be considered as good by this tester, and otherwise will be considered as bad. Here is the schematic diagram of the circuit: To use this instrument, we have to select S2 […]
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This continuity tester gives a beep sound if detect an electric current conduction between its probes. Here is the schematic diagram of this audible cable/component tester: Audible indication gives the benefit of “free eyes” compared to LED or other visual indication. Your eyes will normally have to keep watching on what is being tested, no more eyes for watching any […]
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Photo-diode can be used for high speed digital transmission, but you have to provide high speed signal conditioner for that purpose. The amplifier circuit shown in the schematic diagram below satisfy the high-speed requirement. The circuit is based on current mode (Norton) operational amplifier, that’s why the response is faster than regular op-amp. The frequency response of this circuit is […]
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