The light tag has no wiki summary.
1
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2answers
130 views
Light sensor plate
Does anything like that exist?:
A4 or bigger sized plate which would with ca. 1 mm precision detect regions of the plate which were covered. So if you place your hand on the plate you will obtain a ...
5
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3answers
789 views
How do you dim a streetlight bulb?
I'm getting a streetlight, most likely with a HPS bulb (high-pressure sodium).
I'll probably hook up some sort of sensor to turn it on only when someone is actually parking lot.
Why do some ...
-1
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1answer
190 views
fluorescent light flickering when on … a circuit problem or time to change a new one? [closed]
It flicker when turning on at most 5 times before remain stable. It does not flicker when turning off. Is it a circuit problem or time to change a new one?
UPDATES
After researching and some ...
1
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1answer
1k views
How could I replace the lamp on a regular projector for a LED lamp?
I have a 1080p projector and I want to change the regular 230w lamp for a LED lamp that uses less energy and lasts longer.
How complex would this be? LED projectors with these specs are ridicously ...
3
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5answers
2k views
Creating a new power source for light-string ornaments
I have a couple Hallmark Star Trek ornaments that plug into Christmas light strings. I'd like to convert the power supply to them from the light string plugged in the wall to a battery pack so I'm ...
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1answer
132 views
Mixing wavelengths to produce light? [closed]
It's a mixed part question:
1) Is there any way to add 2 wavelengths outside of the visible spectrum to create a wavelength in the visible spectrum?
2) If this is possible, would those wavelengths be ...
1
vote
2answers
236 views
Can a cathode tube light be run off a battery?
I have two cathode tubes I bought for my computer case back in the day. they are the standard sata connection to the PSU.
My question is can I change the plug end that of a 9V battery or is this ...
4
votes
1answer
921 views
What are the relevant parameters for a reverse-biased LED light sensor?
Following this appnote (PDF) on using photodiodes, I'm connecting an IR LED as a light sensor and emitter, configured like this:
To emit light, I pull PIN1 high ...
1
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1answer
1k views
Driving 12v Halogen lamps (Downlights)
12v Halogen lamps, do they need any special driving?
I have seen on some transformers that they output Half-wave rectification to the 12v halogen lamps. Is this how they should be driven or can ...
3
votes
2answers
233 views
Light detector linearity with varying wavelength
Given the same intensity of light, in varying wavelengths, which is typically more linear with their output: Cds (photo resistor) or a Photo transistor?
I would assume that the junctions in the ...
4
votes
3answers
431 views
What's the problem in designing a bright enough LED lamp?
So far the most powerful household LED lamp I've seen had consumption of 2.1 Watts and gave light equivalent to maybe 15-25 Watts incandescent lamp. That's maybe good for illuminating a Christmas ...
5
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4answers
259 views
How do I manage a large array of “motion sensors” and lights?
I'm a web developer / system admin and I have a client project with a project that is just beyond me. In a nutshell, we need to the following capabilities:
Track the status of hundreds of Passive ...
7
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6answers
10k views
Arduino Home Light Dimming
The drywall is just starting to go up in my family’s basement project. I’ve been looking into residential light control systems. Some of the ones I’ve seen have been an upwards of $2,000. I’m thinking ...
8
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1answer
186 views
LED current while off
I have a vague recollection that while off, a LED can actually receive light and generate a small current (in uA).
Is that correct? How does that work? What is the best way to prevent this?
3
votes
3answers
409 views
Are there any Wifi/Networked Lights available to purchase?
Summary
I'm trying to find a light that can be connected straight into a network via WIFI or LAN Cable (cat5, etc..).
Details
We have a server which handles automated builds and deployment for our ...
1
vote
2answers
178 views
Which infrared bulb should I use with a photodiode?
I'm currently using a photodiode (found here) along with the appropriate emitter to send data between mobile robots. I'd like to the sensor to optionally be used as an ambient light sensor using a ...
1
vote
2answers
221 views
IR-near visible light detection
I want to detect light near 10 micrometer wavelength. It seems like photodiodes are mainly targeted for 1 micrometer range. Is there any detector/sensor for 10 micrometer wavelength ?
2
votes
2answers
311 views
Correct EL Driver Rating for 8 Channel Sequencer
I'm trying to use an 8 channel EL sequencer (found here) to control eight 10-foot segments of EL wire. I'm having trouble figuring out what the appropriate length rating is that I need on an ...
4
votes
4answers
467 views
Flash a fluorescent tube
Is it possible to build a circuit to make a fluorescent tube flash on and off for use as a lighting effect? If so, how?
Also, if the above is possible, can it be used to flash more than one tube at a ...
3
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3answers
2k views
How to make a simple daylight on-off switch?
I have a project planned where I want for some LEDs to turn on when it's dark and turn off when it's light. I have some transistors, diodes, and a photoresistor(and of course other basic components). ...
5
votes
1answer
1k views
Measuring light levels with a photodiode and an ADC
I'm trying to use a photodiode to measure light levels via an ADC on an ATMega168. I've got the microcontroller code working properly (measuring values on a pin and reporting it as an led brightness) ...
2
votes
1answer
1k views
How to connect a light dimmer for my lamp
I have a light dimmer i want to connect to a a floor lamp. I have tried to look for some diagrams but haven't been able to find some.
There is a diagram on the dimmer but I don't understand it.
I ...
4
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5answers
422 views
Need comments and ideas for LED flashlight project
I'm thinking about making a simple LED flashlight.
After doing some research, I think I'm going to use some 5 mm 12 Cd white LEDs with 3.6 V drop which can pass 20 mA. I'm not yet sure how much ...
4
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5answers
2k views
Why do my compact fluorescent lamps keep dying?
I know that this question may be off-topic here, but I'll ask it anyway since they do have electronics inside.
I've noticed that my fluorescent lamps keep dying after only couple of months of use. ...
7
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10answers
2k views
EMI: CFLs vs Incandescent Lights in Your Lab?
Being a green-oriented treehugger, I've put in all CFL lights in my house. Just as much light for about 1/4 or 1/3 the power. Nice, but flourescent lights put out a lot of EMI. Does this cause ...
4
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2answers
1k views
LED Driver for 300mA LEDs
I'm trying to put together a project with some bright LEDs but I'm not sure how to control them. Ideally I'd like to drive about 64 of these LEDs that have a forward current of 300mA and voltage drop ...
5
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11answers
4k views
What is the best Magnifier to use for general electronics duties
I am looking for a magnifier tool for an electronics workbench and was wondering what sort of product would be best.
The device must be an all-rounder capable of doing some SMT as well as through ...
8
votes
4answers
734 views
Car Tail light - why the extra components?
I'm replacing the LED in a car tail-light. Naturally, it will run off 12V (battery) but the circuit I have uses just an LED and a 0.6w (440ohm) resistor. But the existing circuit includes two, larger ...
3
votes
3answers
485 views
How do I build a cheap/efficient mains adapter for some LED lighting?
I've been considering building some LED lights to replace the mains-supplied lights in my house (as a more efficient alternative). For it to be worthwhile though I'd need to build an efficient UK ...
5
votes
3answers
5k views
How to build disco lights?
When I was a teen, I joined an electronics club and built a disco board. I had 5 light bulbs, I painted them different colors. Then I built a board which was connected to these light bulbs. I'd ...
5
votes
4answers
230 views
sensing light and outputing voltage suitable for audio
I have an idea for a project where I use a pc fan to make an oscillator. The oscillation is created by the cycle of light/dark falling on a light sensor as the blades of the fan rotate.
My initial ...
21
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3answers
1k views
8
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4answers
518 views
Create multi touch display for full light
We have been given a project at uni to create a multi touch display.
I've done some research into this and a lot of them call for special film on the glass or use a projector (meaning it needs a ...
