This is a circuit of a touch switch used to turn on and turn off the electronic device that is connected to the 220V home electrical installations. This is a very simple circuit which use SCR T103 as the switching part. Components List: R1 : 2M2 R2 : 10K R3 : 1K R4 : 2K2… Read More »
This insect repellent circuit will repel insects such as mosquitoes, flies and cockroaches from your home or yard effectively. circuit uses a specific frequency to disrupt the insect so the insect will go away from this circuit. This insect repellent circuit can be placed inside or outside the home (for speakers). If you want to… Read More »
The following circuit diagrams are tone detector circuit diagrams which also known as sound activated switch circuit. Actually, these circuits use microntroller for switching because the circuits were designed for robot start up activation. But you can build switching module using relay. You may make a trial to use this circuit for other applications such… Read More »
This is the circuit diagram of a voice operated relay. It similar with sound activation switch circuit which will turn on and turn off (connect and disconnect) the switch depending on the sound input. The output switch of this circuit is act by a relay. Components list: R1, R7 : 1K R2, R4, R8 :… Read More »
This is a sound activated switch circuit. It’s will turn on and turn off based on a loud sound such as clapping your hands. You can adjust the sensitivity (how loud of a sound will activate the circuit) from a pin drop to a Mack Truck Horn. Very practical for a variety of projects. Add… Read More »
This is a motor speed controller circuit diagram built based MAX4295 from Maxim. By using this circuit, you will be able to control the speed of motor movement. Resistor R1 biases the potentiometer to match the input range of U1. Full counter-clockwise rotation of the pot corresponds to maximum-speed reverse rotation of the motor. Mid-scale… Read More »
The following diagram is the circuit diagram of basic monostable multivibrator based IC timer 555. This circuit uses only 4 electronic components that are a timer IC, two capacitors and a resistor. Components List: A multivibrator is an electronic circuit used to implement a variety of simple two-state systems such as light emitting diodes, timers… Read More »
This a two station intercom. It uses two wires to run between each intercom unit. Each is self contained with its own battery, speaker, microphone and amplifier circuit. An LM386 audio power amplifier is used. It is widely available, used a minimum of external parts and is well suited to battery operation. It will give… Read More »