Dark Sensor
Dark sensor using 2 transistor BC547 When light falls on LDR, its low resistance drives the transistor T1 into conduction. This keeps transistor T2 cut-off due to low base bias. The LED does not get power as long as ambient light…
Dark sensor using 2 transistor BC547 When light falls on LDR, its low resistance drives the transistor T1 into conduction. This keeps transistor T2 cut-off due to low base bias. The LED does not get power as long as ambient light…
This simple circuit of electrical appliance protection is to protect your electrical appliance during irregular power supply. Normally when power goes off we forget switching off our appliances. Especially in India where power cuts are very frequent we tend to leave…
LED Flasher circuit using NE555 timer IC R1, R2, C1 and the supply voltage determine the flash rate. For a variable flash rate, replace R1 with a 1 MΩ pot in series with a 22k resistor. The purpose of R3…
USB reading lamp is powered using USB port. The USB port provide 5 v and 100mA which is sufficient for this circuit. Cut the one end of the USB cable and use RED(pin1) and Black(pin4) for 5v positive and negative…
10 Stage LED Sequencer Components IC1- CD4017 IC2- NE555 C1 – 1μ C2- 0.01 μ R1 – 470 Ω R2 – 100 KΩ R3- 100 Ω LED1-10 – RED LED 9volt DC power supply. …
Below is the circuit for variable dc power supply R1- 240 Ω R2- 5K VR R2 can be replaced by fixed value resistor for fixed power supply. Following formula can be used to calculate output voltage. Vo=1.25(1+R2/R1) Output voltage should be2…
This circuit will drive a 40 watt fluorescent or two 20-watt tubes in series. The transformer is wound on a ferrite rod 10mm dia and 8cm long. The wire diameters is 0.61mm wire for the primary and 0.28mm wire for…
12v LAMP Dimmer Parts IC 1 – NE555 Transistor – 2N2955 -1 Resistance – 1k(2 no.), 100 Ω Variable Resistance – 50k Capacitor – 0.1 µF Diode – 1N4001 – 3 12v 2 amp Bulb Input Voltage is 12v. To…
Today LED has become an integral part of consumer electronics. LED TV, LED Display, LED Lights and so on. These are becoming very popular because of there low power consumption. What is LED? LED stands for Light emitting diode. A…
Below is the regulated DC power supply( 12, 8, 5 v) circuit. This circuit can be customized by adding 9v and 6v voltage regulator. Also, the 4 diodes can be replaced by bridge rectifier. Parts list: T1 – Step down…