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H Bridge Circuit
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4 Band Resistor
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Light Laser LED Circuits
Light Laser LED Circuits
Light Sensing Circuits
Light Dimmer Circuits
Simple power Supply for LEDS
LED's are great display tools. Their prices have decreased to a point where they are replacing more conventional light sources. In one sense their characteristic need for low voltages is an advantage e.g compatibility with I.C drives, but this voltage requirement can also be a disadvantage. I wanted to light some LED's in a simple sign...
Mains supply fail Emergency Light
The circuit comprises two sections: charger power supply and LED driver.The charger power supply section is built around 3-terminal adjustable regulator (IC1) LM317, while the LED driver section is built around transistor BD140(T2). In the charger power supply section, input AC mains is stepped down by transformer to deliver 9V, 500mA to the...
LED Flash Driver with HT2050
This circuit is based around HT?2050 manufactured by HOLTEK semiconductors. It is a low cost, low-power C-MOS LSI designed for lamp andLED flash driver. It requires minimum external components.You can operate it with just two AAA cell or 3v Battery.Circuit has five flash outputs with 10mA drive capability that can implement random or sequence...
Light Control System (OP295)
Sensing unit consists of infrared emitter OP295 to produce the infrared beam, & two detectors in front of the emitter to detect the infrared beam OP598. Since the main idea in this device is to know person direction; and so, to get this approach, we have to use tow pieces of infrared detector in order to identify the direction of the person....
200W Lamp Flasher with 555 timer
200W Lamp Flasher is used to flash lamps, bulbs and halogen lamp to give your product that attracting look.
Light Sensor Switch
Light Sensitive Switch is a simple project which operates a relay when the light falling on the LDR goes below a set point.
Led Flasher with a BC547 NPN transistor
This is a novel flasher circuit using a single driver transistor that takes its flash-rate from a flashing LED. The flasher in the photo is 3mm. An ordinary LED will not work. The flash rate cannot be altered by the brightness of the high-bright white LED can be adjusted by altering the 1k resistor across the 100u electrolytic to 4k7 or 10k. The...
Infrared mains remote control Switch
The infra-red (IR) toggle switch project described here is aimed to provide control mechanism for electrical appliances that do not have remote operation features. The goal is to construct a black box where you can plug-in your 120V AC appliance and control ON and OFF operations with any modern IR remote control devices. Modern IR remote...
Power Failure Light
This is a very basic power failure lighting circuit based around a relay. This simple circuit has many uses, from lighting up rooms and walkways in the case of a power failure, to monitoring and security uses. There are many different power failure circuits out there based on 555 timers or transistors but they all have different problems...
RGB LED Controller with PIC18F25K20
In this project it was used the ?Piranha Super-flux RGB? Led of common anode, and the PIC18F25K20, in order to generate combinations of colors. It has two function modes, automatic that generate the color sequence that is stored in the ?C memory, and the manual mode in which you can select one of the seven possible colors. The control of the RGB...
Mains Blinking LED
I needed a pulsating light for a certain signaling. Voltage was 230V. So I decided to make a simple circuit, consisted of a LED diode, two capacitors, two resistors, a diac and a diode. Activity of the circuit is extraordinarily simple. The capacitor charges by the diode and the resistor. When the voltage on the capacitor achieves 30V the diac...
Fake Alarming LED Flasher
The parts to the right of T1 form a simple Joule-thief ('Blocking' oscillator) circuit which boosts the 1.2v supply to 3.5v to operate the LED. C1 is used to extend the charge and discharge cycles to increase brightness and efficiency. Components R, C and D1 form a simple timing circuit which, with the values shown, is about 1 sec per flash....
Dot matrix LED display
The device comprises two parts: LED control board and LED display board. The two PCBs are designed to fit together one behind the other using two sets of dual row connectors and 4 spacers. One of this connector is used for the electrical connections, while the other is only used as a mechanical connecting element. The core of the device is...
Bicycle weel Light Display with ATTiny26
48 LEDs total, 24 on each side of the board. This gives higher resolution patterns, and they can be seen from both sides of the bike. The LEDs are controlled from a series of 74x373 ICs connected to an 8 bit bus on the microcontroller. As opposed to shift registers, all 48 LEDs can be updated in 20-30 microcontroller cycles, leaving plenty of...
G1216B1N000 dot graphics display
A serial interface and bias supply for the Seiko-Epson G1216N000 using an AT90S2313 because there just aren't enough applications examples for this display on the web. The display is a pretty old transflective gray mode TN LCD design with ok, but not great contrast. Its contrast is better than the screen shot above. The display's saving grace is...
Lamp Dimmer / Motor Speed Control
The diac is a common component used to trigger triacs. The construction of a diac is similar to that with a transistor, but with both junctions doped to similar levels so that the two junctions' revers break down characteristics are similar. This is a fun project to demonstrate the use of a pair of bipolar transistors operating in their negative...
LED runner with 74LS163
This is a very simple circuit to build, just take note of the control pins on each IC, since both have enable inputs for counting or output, but once set you don't need to worry about them. From left to right, the first IC is a binary counter, 74ls163, that is used to generate the address numbers we are going to use in the second part of the...
555 LED flasher
This circuit is built around one of the most popular timer integrated circuits, the 555 timer. It will flash the led on and of at regular intervals. From left to right, the two resistors and the capacitor set the time it takes to turn the led on or off, by changing the time it takes to charge the capacitor to trigger the timer. Next is the 555...
InfraRed Detector (PIC12F629)
This unit uses one TSAL6100 IR/LED emitter from Digi-Key. This IR diode has a narrow (10 degree) radiation pattern at 940 NM. It is driven via 2n2904 transistor for maximum current pulses. The detector is a Vishay TSOP4838 38Khz integrated receiver module. The 38Khz signal for the emitter is generated in software. Here is the idea: Send out a...
LCD to a PC Parallel Port
The circuit is pretty simple. The data lines on the LCD match up well with the data lines of the parallel port, and extra parallel port I/O lines can be used to simulate the RS, R/W, and E signals on the LCD. The LCD module is pretty low-lower (with the exception of the backlight), so I found that it can be powered from most parallel ports. It...
Audio Controlled Christmas Lights
The basic Idea was to have Christmas lights flash with the music. In my design I use an ordinary amplified computer speaker, a diode bridge, and a ‘CRYDOM’ SSR (Solid State Relay). In order to increase the time that the lights were on as well as protect the SSR I used a Diode Bridge to rectify the signal from the amplifier circuit.”
Xenon light pulser
Flash lamp is made ??with experimental parts removed from a disposable camera flash circuit.Xenon try to use what I think is easily affordable experiment. AC100V to a voltage doubler rectifier, DC voltage of about 270V is derived. This voltage is R2, C3 is charged through a short period of time as well. At the same time the trigger capacitor C4...
Simple 3-6V LED Flasher
If you are familiar with LED flashers using transistor, you may know the basic one uses two transistor, one capacitor and three resistors. There is other kind of oscillator called "flip-flop". As I'm starting to develop some basic circuits, I need a simple LED flasher that can be used in many other applications. The RC circuit is connected to...
disposable camera strobe light
If you have no idea what is a "strobo", "strobe", "stroboscopy" or whatever way it is called, it is simply a flashing light. It is usually used on police cars, 'disco' places and many interesting applications, including scientific ones. This project is dangerous because it implicates high voltages, it can be lethal. Please read the Disclaimer...
How to connect LED's directly to MAINS
A LED is defined as "light-emitting diode: diode such that light emitted at a p-n junction is proportional to the bias current; color depends on the material used" [Princeton University]. As the LED is a diode, it doesn't conduct electricity in both ways and it is not a resistor, so it needs an additional resistor. The value of the resistor is...
This circuit typically uses a voltage around 300 volts for the main high voltage supply and needs a low voltage supply of typically 6 to 15 volts. 555 pin connections not shown above: 1 goes to ground / negative of both low and high voltage supplies. 4,8 both go to positive low voltage supply, of 6 to 15 volts. 7 does not get connected to...
Strobe Light circuits and info
The power supplies for electronic flash and strobe equipment operate at extremely lethal voltage and current levels. The energy storage capacitors in even the smallest disposable camera flash operating from a 1.5 V AA battery can be deadly under the wrong conditions. Line powered strobes have added danger of high power at high voltage AND are...
Current Dimmer for white 24 LED array
This simple Linear circuit provides continuously variable regulated current (~25-400mA) from a 4-6 Volt source. I chose a linear design for simplicity, reliability, ease of repair, and to avoid switching EMI in my Cave Radios. The circuit requires only 0.2V headroom above the parallel LED Array voltage to provide regulation at maximum current....
LED SignBoard with PIC 16F84A
The pins RA3 to RA0, are used as outputs driving each column LED. The pins RB0 to RB7 are used as outputs driving signal for each column LED. The 74HC154 (Decoder 4 to 16) is the chip that decodes the signal into a binary digit dekaexapsifio. In the left figure all the pins of the door at a reasonable RA 0 (Low), in which case only the output 0...
8 LED Effects using PIC16F84A
Five pins RA0 to RA4 are used as inputs. The pins are connected to the 5V average resistance 10K (Pull-up). So when no switch is not depressed all the pins have a high potential (HI +5 V). When one of them is pressed then the foot is connected to get a low potential (LOW 0V). When a switch is pressed, then the phenomenon of 'Bounce' (Debaunce),...
2 LED Flasher with 555
The circuit is based on the IC1 that is 555, for the creation of alternate flashes from the two led D1-2, that can be also different colour. The frequency of alternation can be regulated from the trimmer R3 and from the C1, if changes his capacity. The supply can become from a battery or from one separate power supply. A use of circuit is...
Touch Light Dimmer circuit
With this circuit we can change the brightness of lamb, with a only key of touch. The key of touch is connected in the circuit, center of which is a special completed IC1, which is the S566B of SIEMENS. This IC, it processes the information of duration of touch and then it checks the brilliance of lamb, according to this information. If we touch...
Ultrasonic distance finder circuit
The circuit described here uses ultrasonic oscillations and operates based on the propagation velocity of these oscillations in the air. Thus, we can easily determine the distance of two points if the time within which the wave travels this distance is measured. There are three main categories of distance measurement methods in use: a) By...
Simple Metal detector circuit with CD4030
Sometimes the precious metals are hidden too deep and are not detected except with complicated devices. In many cases, however, small pieces of precious metal buried near the surface can be detected by relatively simple means. Everyone is very attractive to find something potentially valuable, hidden a few centimeters below the soil. So many...
Fully automatic watering circuit for flower pots
Many times for various reasons we forget or can not water the plants that we have in our homes. And many humidity sensors units just notify us with a beeping sound or with a flashing light, that the pot needs watering. But what if we are away from home? This circuit comes as a solution to this problem. Depending on humidity of the pot at...
Simple deep searching metal detector circuit
The principle behind a metal detector is really very simple. Proof of this is the circuit that follows, in which it proves that the construction of a metal detector can be done in the minute, with few components that we find very easily everywhere. With the circuit of this metal detector, it is possible to detect a metal coin in depth of 90 to...
Sub-Harmonic Bass Converter for Electric Guitars
The sub-harmonic bass generator is a sound producing unit for guitars. The sound it produces looks very much like that of the bass guitar. The octave generator is sometimes quite unusual since it does not produce any of the usual ways of coloring the sound, such as filtering or distortion. Instead, a frequency division system produces outputs...
Echo Depth Sounding Sonar for Boats
In the past the sounding (sea bottom measurement) was done with the "bullet", that is, with a heavy lead object that the seamen plucked into the sea hung from a calibrated rope. As soon as the "bullet" reached the bottom, the depth appeared directly from the calibration of the rope. This arrangement still exists in some yachts. The big...
100W HiFi Audio Amplifier Circuit
This Amplifier was designed to have the following specifications: Distortion less than 0.1% at full power of 100W even at 20KHz. Power has to be attributed to an extended bandwidth. The output transistors must be protected against short circuits. The power supply must be symmetrical so that no electrolytic capacitors are needed at the outlet....
Plant-Pot Water Level Indicator Circuit
A series of LEDs serve to alert the gardener when plants need water. Using two conventional digital integrated LEDs and a series of LEDs, we make a very useful device for gardening. The device detects the amount of water in the pot and alerts the grower. The circuit of the device is shown in Figure 2. The water detection is made from the bottom...
Analogue Sound Preasure dB-Meter Circuit
The best human ear can capture sounds from 20Hz to 20KHz. These limits are known to be the broadest that can exist. Normally the normal limits range from 100Hz to about 13KHz and depend on the age and health of the individual. We for our measurements and to have a good accuracy we will get the limits of 20Hz to 20KHz. A sound to be heard does...
Digital Signal Integrity
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