Free electronic circuit design and schematic diagram
The circuit diagram below shows us about a form of PID controller. The input signal is buffered and amplified by a non-inverting amplifier and the gain of this stage defines the proportional gain P of the controller.The amplified error signal passes in parallel through an integrator (top) a unity-gain amplifier (middle) and a differentiator (bottom) all of which have inverting […]
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This is a Water Level Indicator with alarm circuit. This circuit is used to indicate the amount of water present in the overhead tank. Not only that, but this circuit also gives an alarm when the tank is full. CD4066 is used to indicate the level of the water through LEDs. Here is the schematic diagram of the circuit: The […]
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This circuit presents a very simple and useful stereo balance indicator circuit that is based on few common external components. This schematic circuit is very simple to build. An visual indication with LEDs for left , right and center balance is provided by this circuit. Outputs from each channel are fed to the two inputs of IC1 connected as a […]
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This is a simple circuit of Touch switch activated relay. This circuit is used to turn on/off electronic relay using touch sensor. This circuit consist of two main parts, they are a decimal counter and an current amplifier circuit. This circuit is need a 5volts power supply. Here is the circuit: As the counter circuit, this circuit uses JK flip […]
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This is an Automatic Cooling Fan Controller circuit. This circuit is very useful during summer to keep our important item and rigs such as VHF and UHF transceivers staying cool. Because VHF and UHF transceivers were sold with no cooling fans and oversized heat sinks. Here is the circuit: This circuit uses The thermistor, R1. It is the heart of […]
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This is a simple 220V power interface circuit. This circuit used as interface for monitoring electric devices and equipments using a computer. The circuit only senses whether the device being monitored is turned off or on. The galvanic isolation between the AC main line being monitored and the interface to the computer is an important aspect of the circuit. We […]
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Figure below shows us a PWM Speed DC Motor Rotation circuit. This circuit has two functions, Forward-Reverse and Regenerative Braking function. On this circuit, we can control the speed of DC 12V motor with Power Mosfet IRF150 using a signal PWM. The Relay RY1 work as control Reverse with the digital alarm, change Q10. The Relay RY2 work as function […]
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