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2
votes
1answer
56 views

Creating an LED array light box

I'm wanting to make a light box of sorts from LEDs and wanted to run it by you to confirm I have the right idea... I have ordered 500 super bright LEDs off eBay and want to wire loads of them ...
2
votes
2answers
113 views

Energy-efficient LED driver circuit

I want to light a normal LED for as long as possible on two AA or AAA batteries. It does not have to blink or so, just stay on. The LED doesn't have to light at the max, as long as it's visible from ...
0
votes
1answer
135 views

How can I power the blue LEDs separetely on this aquarium light?

I have a Beamswork LED aquarium light like this. It has a 3 way switch: All LEDs off Blue LEDs on only White AND blue LEDs on It has a single mains power plug. What I want to do is make it have ...
-1
votes
1answer
41 views

Optoelectronic lab involving filtering of image with white light [closed]

This is an optoelectronic lab experiment involving filtering of the stylised image of a house with white light and grating. The objective is to filter the bars on the upstairs window and the ...
2
votes
2answers
147 views

How much can I safely plug into a light socket converted to a standard outlet?

I just moved my office desk from our extra bedroom on to our stairway landing. The tricky thing was that there was no wall outlet to plug anything into. However, there was a nearby light socket, ...
0
votes
1answer
117 views

Light bulb exploded [closed]

This morning, one of the lights in my house began to flicker. I didn't think much of it, and left the room to get a drink. While I was in the other room, I heard a bang, and came back to find broken ...
1
vote
1answer
108 views

How to switch light on by standing on a mat

I'm working on a project for school. And I have this dance matt. As long as you stand on that matt the light should go on and stay on until you step off the matt again. But I have no idea how to make ...
0
votes
1answer
110 views

virtual light communication

I have to design a project that uses an LED to transmit data and a LDR to receive the data or signal from the LED. But the problem is I have to use two Arduino UNO boards, one for LED transmit and ...
6
votes
3answers
352 views

Continous light - do LED s flicker like fluorescent lights?

Continous light - do LED s flicker like fluorescent lights? Under flourescent light there is a flicker. As i understand LED work only with DC current, thus they have a AC to DC transformer circuit ...
-6
votes
1answer
49 views

Ceiling light holder [closed]

I touched the wires of a ceiling light holder with plyers, it made a spark and all of the power in my room was gone. WHAT DO I DO?
-1
votes
1answer
111 views

LED RGBW Lighting, Will this Design work?

I've got this schematic for a very small lighting setup for my basement. The goal is to have two fixtures that have red, green, and blue lights that can be controlled with knobs on a Separate ...
34
votes
6answers
5k views

Does turning a lighbulb on and off repeatedly use more energy than just leaving it on for hours?

Let's say I have a 60W bulb in a lamp in my bedroom. If I kept the lamp on for 2 hours straight but the next day, I switched it on and off 10 times in intervals of 5 minutes. Which scenario would use ...
6
votes
2answers
329 views

How to start with creating a device?

I have recently wondered if I could build some kind of useful and cool device, using some sensors, transmitting signal and doing something with it - I think people who answer questions on this site ...
4
votes
2answers
322 views

Basic circuit to keep LED either on or off depending on night/day

How can I have a LED either on or off (not in between) depending on night or day with basic electronics? I have created the circuit below, but it only shines and in darkness it dims. The ...
0
votes
2answers
200 views

Do dimmer switches work properly with any kind of lamp? [closed]

I have a dimmer switch installed in my room that I like very much, but lately incandescent lamps became harder to find, and soon (in a few years or so, if I'm not mistaken) they will be gone to be ...
0
votes
2answers
185 views

LED brake lights - detecting voltage drop?

I am trying to light up some LEDs on my Rustler VXL RC car only when braking/reversing. I found out that on my receiver I have three wires: black(-), red(+), white(+). The one that interests me is the ...
1
vote
1answer
652 views

Building a 3x3x3 LED cube?

I need to built a 3x3x3 LED cube. I need to be able to turn every LED on (not at the same time) in different patterns. I need to use Charlieplexing (note that any other method is not a viable ...
7
votes
2answers
193 views

What factors affect the brightness of electroluminescent wire?

I'm interested in experimenting with creating my own electroluminescent (EL) wire. I've seen some videos on creating your own by Jeri Ellsworth. I have a few additional questions. I understand that ...
4
votes
1answer
211 views

Solid state relay for home lights application

My application is controlling home lights. I want to use relays to switch lights on and off. My circuit should work on all kind of lights such as neon lights, halogen lights, strobe lights and others. ...
2
votes
2answers
204 views

A christmas light bulb question

This may look like a homework, but it's not. Actually it is related to Christmas. My Chrismas lights in front of the house are constructed from segments. Each segment consists of 16 incandescent light ...
1
vote
3answers
84 views

What lamps are out there that don't flicker and give off warm light (like incandescent)?

In the past few years several countries stopped producing 100W incandescent lamps, and in a few years they may disappear to be succeeded by fluorescent lamps. I really don't like the flicker and the ...
5
votes
2answers
688 views

Dimmer to bulb control

I need to control a bulb of 220V, with different intensity light levels. I've an Arduino Uno Board, which receives a variable voltage from a Light-to-voltage converter (TSL12S) (Like a ...
7
votes
1answer
1k views

How do the lights on stairs work?

I remember that there's a very simple circuit diagram that explains how there can be 2 light switches for 1 light and that regardless of which switch you turn 'on/off' the light is toggled on/off. ...
1
vote
1answer
129 views

Light switch setup for bedroom [closed]

on my bedroom I want to put two 220V lights on the side of my bed, and I want to control them with 3 switches: the main switch is beside the door, and will commute both lights on and off. two ...
1
vote
1answer
440 views

Use 3.5V power LED connection on motherboard to control a 12V lighting accessory in a computer case?

Background for the problem: I rebuilt my computer in a new case where the components fit a bit better. Everything is great, and I have no issues with it. However, because of the way they engineered ...
4
votes
2answers
225 views

light system for stairs

I have a stair made of several steps. I want that when I put a foot on a step, the light of the next step is turned on. Each light is placed just under the edge of the step. If I use LEDs as lights, ...
0
votes
1answer
102 views

Low Voltage Photosensor

I'm looking for a photosensor/photo IC part (combination of photodiode, linear amplifier, Schmitt trigger and output transistor) that can be powered with 3.3V. Fairchild QSE256/257/258/259 is almost ...
2
votes
3answers
231 views

using led stripes with external battery: any side effects?

i have to power some led stripe from ikea with a drill battery: On led stripe power is written: 12V 0,25A. and on drill power: 12V 2A. Now i want to power n led strip (for example: n=4) and i ...
0
votes
0answers
58 views

Michelson Inteferometer [closed]

If one of the outer mirrors on a Michelson interferometer was to be misaligned by a small angle of theta, what would be the shape of the interference pattern in the detector plane? What would happen ...
1
vote
2answers
164 views

Do I need to solder on my DE2 board to replace a broken segment?

I've already posted a question here about this when I realized that all things were not right with my Altera DE2 board: Is this display broken or is it a bug? After verifying that the segment indeed ...
6
votes
3answers
244 views

How can I achieve very bright light?

I'm not sure if this is right site for this, but couldn't find better. I've been given an task to create something that has light intensity like police beacon. I need it to be cheap, so I'm looking ...
3
votes
2answers
122 views

Identify a light emitting component

here's a picture of component that is not a LED but emits light, it's a tiny glass light bulb with a resistor and a red plastic case for mounting it.
4
votes
1answer
178 views

Designing a wide-range light detector circuit

I'm looking for a few hints in designing a light detector circuit. Priorities are that the circuit is simple (both as in few parts and as in relatively easy to understand), rather cheap, and can ...
0
votes
1answer
242 views

how many light bulb for one relay?

i've just done this tutorial: http://www.arduino.cc/es_old/Tutoriales/Rele it works great! i've done it in a breadboard (with two 5v circuits for test) and then soldered (for just does not have 220v ...
4
votes
1answer
164 views

ambient light rejection in absorbance sensor

I'm making a sensor to measure light absorbance in a sample where the geometry varies over time. I found a very nice transimpedance amplifier, the AD8304 designed for use with PIN photodiodes with a ...
4
votes
1answer
210 views

What type of method for producing White-Light LEDs is the most common?

There are two primary ways of producing white light-emitting diodes (WLEDs): To use individual LEDs that emit three primary colors red, green, and blue and then mix all the colors to form white ...
2
votes
1answer
206 views

Power Off Delay circuit

I'm looking for a timer that starts when power is removed. Here is the use case: The head light on dirt bike my turns off with the engine. This good when it's parked. This is very bad when doing ...
3
votes
2answers
941 views

Powering 10watt light bulb for 24 hours using solar power

I am a total noobi to solar power and even electricity so I appologies if I am asking a silly question. Imagine I have a 10watt light bulb which I want to leave on for 24 hours a day. Will I just ...
4
votes
1answer
612 views

How to find Emitter and Collector of an LDR

How can we find the emitter and collector of an LDR. I am using it in the following circuit but I don't know how to identify which terminal of the LDR is emitter or collector. Here it is mentioned ...
4
votes
2answers
2k views

LM358 (Op-Amp) For a Light Sensor?

I'm looking at this light sensor: What exactly is the point of having an LM358 (a Dual Op-Amp I believe) for a Light Sensor? Maybe I'm missing something....but what exactly purpose does it serve? ...
-1
votes
1answer
86 views

12 VDC Power to Illuminated Button

I want to hook up a push button on my photobooth following this guide. I already have a serial cable and a port on my machine. The button I will be using is this one here. It is an illuminated ...
3
votes
2answers
246 views

What type of LED lights are needed for detecting retro-reflective markers for motion capture project?

I've a project in which I want to add 10-12 led lights around webcam's lens so that the camera can detect retro-reflective tape in it's viewing area. How this process works is something like this. ...
3
votes
2answers
304 views

Power LED light from battery when mains fails

I'm attempting to design a circuit for some LED lighting that will be powered from a mains connected 24V DC transformer but if the power fails then the a battery should take over as the power source ...
0
votes
1answer
328 views

How to operate tube-lights using relays

I am using the circuit mentioned in one of the articles of EFY (Ref.) .I have added the freewheeling diode across the relay, and I am able to turn On/Off bulbs as well as CFLs successfully.Now I want ...
3
votes
2answers
151 views

How to measure, with timestamps, changes in the received luminance?

I'm working on a project that is in need of some testings to validate it. I need to make some readings of luminance from a light source and store this reading with a timestamp (milliseconds ...
1
vote
2answers
381 views

What is going on inside this nightlight circuit?

I've got a small nightlight in my hallway that has a photocell on top so it only turns on when it's sufficiently dark out. Sometimes the light will be off and a shadow will cover the nightlight as ...
1
vote
0answers
132 views

How to deal with mains/grid spikes?

Sorry if this is the wrong place. I thought it fit better here than DIY Stack Exchange. I replaced a 230 V halogen light bulb with a 6 LED package. Now I notice that all the LED's blink every 15 ...
1
vote
1answer
73 views

Why are handheld devices always backlighted nowadays?

...And mostly, why is it unable to turn this backlight off? Gaming Consoles (and Mobile Phones, PDA's and other handheld devices) are always backlighted nowadays. Older devices, such as the GameBoy ...
7
votes
1answer
304 views

How is an LED constructed, is it possible to build my own

I wondering if it would be theoretically possible for me to build my own led or oled. I am aware that this is not very practical, I'm more interested just as an exercise. I understand the basic theory ...
2
votes
2answers
849 views

What parts do I need in order to connect a light to my netduino?

I'm software engineer trying to get a little electronics project working. I have a netduino plus. I want to hook up a huge light like this and make it turn on and off. Where do I start? What would it ...

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