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Running LED by 220v

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This circuit is simple way to running some parallel LEDs by direct 220v. The output current depend on the capacitor and the resistor and can calculate from following equations: The series capacitor in AC current work as a resistor called (Capacitive reactance) in first you have to find it from following formula: Xc = 1 � (2p * f * C) Where: Xc is the Capacitive reactance in ohm f is the frequency of mains voltage in Hz(usually 50 or 60Hz) C is the capacitor value in Farad V is mains voltage Then add this Capacitive reactance to the resistor to find total resistor (Z): Z= v( (Xc^2)+(R^2) ) Now you can use Ohm's law for finding output current: I = V � Z EXAMPLE: Find the output current for following circuit? Xc = 1 � (2p * f * C) Xc = 1 � (2p * 50 * 0.0000001) Xc = 31847.1 Ohm Z= v((Xc^2) + (R^2)) Z= v((31847.1^2) + (150^2)) Z= 31847.4 Ohm I = V � Z I = 220 � 31847.4 I = 0.00697A = 7mA Since 5mm LEDs need to 5 to 10mA for running so this capacitor and resistor value is enough to runn...

How to install and programming an LED sign board

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Each LED board contain 3 basic parts: LED module, controller, power supply LED module LED modules can connect together to make a big display. there are single color LED modules, 2colors and full colors(RGB) LED modules. since traditionally LEDs when leaves in sunlight for long time loss its first brightness, so that modules make by special LEDs that have higher resistance to sun ray.   Controller controller (some time call mother board) contain LED display driver, memory and back up battery. Power supply power supply is a 5v regulated adapter and its current is between 1A to 50A or more (according to number of modules that make bigness of display) Note: connecting + and - in reverse causes damage for both controller and LED modules. Programing process For programming the LED board first must install "HD2013" program on your computer. You can download it from following link( password=168 ): https://drive.google.com/open?id=0B4jg9KxpTKGTeWZzbU11Yl82cG8 when installing comple...

FM transmitter

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This circuit is a FM transmitter. can run it by 9v battery. the power consumption is very low about 10mA so a small 9v battery worked for long time. The frequency of radio must set between 88 to 93 MHz. The circuit contain trimmer for set frequency of transmitter. Part list: Transistor BC547(2pcs) Capacitor 10uF(2pcs) Capacitor 1nF(2pcs) Capacitor  5.6pF Trimmer 2-18pF Electret microphone Resistor 4.7k(3pcs) Resistor 100k Resistor 10k Resistor 270 ohm Coil 4mm diameter 5 turns air-core (2pcs) Antenna 10cm  

Solar tracker circuit

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This circuit is an one axis solar tracker. Today this circuit used in modern solar street light and solar systems in homes for increasing the efficiency. I tested it and work well. Best dc motor for this circuit is cordless drill motor (without removing gearbox)because that is very powerful and can move your heavy solar panel easily. In following video you can see how it work, however i test it without solar panel. Parts list: IC LM324 LDR(2pcs) Transistor BD139(2pcs) Transistor BD140(2pcs) Potentiometer 100k potentiometer 10k Diode 1N4007(4pcs) Capacitor 100n Resistor 47k Resistor 15k DC Motor 6 to 12v   Please subscribe to my YouTube channel here:  https://www.youtube.com/c/EngMousaalkaabi?sub_confirmation=1

High DC voltage PWM dimmer

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This circuit is a high voltage PWM dimmer for DC load. it can be very useful because most dimmers that available in markets are 12 to 24v. I tested it by 33v(because my power supply can't give more voltage)  but it can work by up to 50v DC. R2 can be 1k to 1.5k. Parts list: IC 555 N-Channel MOSFET such as IRFZ44 Diode 1N4148 Zener diode 10v 1W Potentiometer 50k Capacitor 0.1uF Resistor 1k(2pcs) As you can see in following fig. there are some parallel horizontal lines in image when you see to a PWM LED from an camera because it flashing with very high speed, that also occur when you want to take a picture from CRT TV display.

PWM light dimmer

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PWM today used in many areas such as solar charger, motor speed controller, light dimmer, mobile battery charger, etc. Following circuit is a PWM light dimmer that used IC 555. By this circuit you can change the brightness of LED lights. It also help to decreasing power consumption because when the LED is ON in fact it flashing by very high speed but the humans eye can not identifies that so we will see it continuous shine.  

AC live wire detector without IC

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This circuit can detect the live AC wire. Can run it by 3 to 9v. You can add a buzzer to circuit. NOTE: don't touch the wires of the circuits for good detection. You can make similar to this circuit using IC4017 or IC4060