Mini UPS Project

Here the simple Mini UPS circuit diagram. This circuit can provide an uninterrupted power supply (UPS) to operate 12V, 9V and 5V DC-powered instruments at up to 1A current. The backup battery will take up the load with no spikes or delay when the mains electrical power gets interrupted. It could possibly also be utilized… Read More »

Automatic Light Controller

This is the circuit diagram of automatic light controller which use 78xx voltage regulator IC series. The voltage regulator ICs deliver a constant output voltage, as against a extensively fluctuating input supply, when the common terminal is grounded. Any voltage about zero volt (ground) interconnected within the common terminal is added to the output voltage.… Read More »

4 Stage FM Transmitter

This is the FM transmitter circuit which apply 4 radio frequency stages, that are a VHF oscillator designed around transistor BF494 (T1), a preamplifier designed around transistor BF200 (T2), a driver designed around transistor 2N2219 (T3) and also a power amplifier designed around transistor 2N3866 (T4). A condenser microphone is wired at the input of… Read More »

LPG Gas Leakage Sensor Alarm

This is the schematic diagram of LPG gas leakage sensor alarm. The circuit operates off a 9V PP3 battery. Zener diode ZD1 is applied to convert 9V into 5V DC to drive the gas sensor module. The SEN-1327 gas sensor module from RhydoLABZ is applied in this circuit. Its output goes higher when the gas… Read More »

Toy Car Remote Control

The circuit, consisting of an infrared transmitter-receiver pair, utilizes IR beam transmission to switch the toy car “on” or “off’, yeah… it will be only switching on and switching off, you may modify this circuit to make the toy car to turn left or right. To operate the toy car, you have to hold the… Read More »

Laser Communication (Transmitter – Receiver)

This is the circuit diagram of laser communication system that transmit the sound or music signals by way of a laser beam. The intensity of the laser beam varies together with the amplitude of the sound signal. The variation within the intensity of the laser beam is converted into a variation in the voltage level… Read More »

Seismic / Vibration Sensor

This is the circuit diagram of seismic / vibration sensor. The circuit simulates a seismic sensor to detect vibrations/sounds. It’s really sensitive and may detect vibrations due to the motion of animals or human beings. So it could be utilized to monitor protected locations to restrict entry of undesirable individuals or animals. The circuit applies… Read More »

Electronic Motor Starter

The above diagram is the schematic diagram of an electronic motor starter circuit. This motor starter protects singlephase motors against voltage fluctuations and overloading. Its salient function is a soft on/off electronic switch for simple operation. The transformer steps down the AC voltage from 230V to 15V. Diodes D1 and D2 rectify the AC voltage… Read More »