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led

  1. R

    LED it's not blinking at the expected rate

    Hello guys, I'm trying to make a led blink at 3 different frequencies, upon successive keypresses. My problem right now it's that it's only blinking 2 times and I don't understand why. D6 is LED, D4 is the test output. Here it's my main function: /*********************************************...
  2. D

    Advise needed for running LED lights from a powerbank

    Hello, I want to build a smartphone camera rig that has LED lights built in that run from a USB power bank. I’ve attached a basic design to give an idea of what I’m trying to achieve. I’ve got no experience with electronics, but can (and have) follow instructions for personal projects. Can...
  3. C

    Building a Rechargeable LED Lamp

    Hello Sparkies of the Internet, I am just a simple man of wood, with absolutely no experience in anything electric. I am however building a lamp for a project that I am doing as part of my course in Furniture Design and Manufacture, and I fear that I have made it slightly too complicated for...
  4. T

    Can anyone help me circuit a Tricorder?

    Hi there! I have 12x 3mm LED's: - 6x flashing - 6x static To this I have a standard slide switch and cell battery holder. My issue is this: how do I link these 14 components to one another and ensure the flashing LEDs stay flashing and the static, static? I believe that a 6V battery will...
  5. N

    Motion triggered battery powered dimmable COB LED light

    My view on life, in any field, is not to produce more but to consume less. Everybody told me this is a very eccentric weird mentality. Perhaps they are right. Nevertheless I have to build my project to make a highly efficient, extremely low drain, motion triggered 12V battery powered dimmable...
  6. 1

    Arduino ON led lights up with no USB, no Vin and no 5V power

    Hello, I am using an Arduino Uno for a soldering station project. I am powering the Arduino through USB port using a L7805 regulator and I saw that if I remove the USB power, the ON led still lights up when I am powering the soldering station. Also, the other led's are semi light up. The Vin and...
  7. K

    Circuit of the switch 12v. led-lighting

    One Bit Switcher I offer my own version of the circuit of the switch 12v. led-lighting for the kitchen based on the dual trigger of the hc74 chip. Created with EasyEDA.
  8. G

    Need build a circuit that flashes 4x

    Guys, I need some help. I need to build a circuit, that flashes a LED 4 times (only 4x, in a short time, like less than 1/2 second), every time that i click a bottom (click switch). If you can draw me a circuit that may work, I'll be grateful (cuz I'm still learning circuits).
  9. R

    Arduino gps speedometer

    Hello, I would like to build a battery powered arduino gps speedometer. In this arduino based project I would like to include a few features. -I would like it to turn on some lights when It detects that the speed is going down (if the speedometer is going at 10km per hour and slowing down I...
  10. sr13579

    How to make Grow Light with LED?

    I made a LED setup with blue and red LED that is supposed to help me with indoor planting. I used total 4 LEDs (2 Red and 2 Blue) for one pot of Portolaca flowers. But I think it is not simulating the sunlight properly. How many LEDs am I supposed to use? How should I make the connection?
  11. J

    Changing flashing LED on module to stay on - use a capacitor? Any help please?

    I'm coming from a programming background and although I'm doing more electronics recently I'm still very much learning. I'm using a bluetooth module (this one https://www.amazon.es/gp/product/B073B1MZQF/ref=ppx_yo_dt_b_asin_title_o00_s00?ie=UTF8&psc=1) It has an LED function but it's really...
  12. W

    LED Drivers capacity

    Hello All, Thanks for having me in your group. Up front I am a disabled senior with no electronics experience at all and to old to learn much. I have always wanted to learn electronics design, repair, build ect. but never got the chance, I envy you guys and have a world of respect for your...
  13. V

    LED + Battery without fading

    Hello everyone, I'm searching for help since electronics are not my field of study... I'm trying to build a simple project that requires an LED with a constant light output (the LED must be wired to a coin battery cell i.e. CR2032). When reading the LUX from the LED I can see the LUX decreasing...
  14. P

    Need Help with LED power supoply and dimmer

    We are converting legacy lighted display boxes from fluorescent to LED. We have had inconsistent results depending on the power supply/dimmer and LEDs used. Our long time electrical engineer consultant sadly passed away and we are left scratching our heads. I know some LEDs require constant...
  15. O

    Need help with alterations

    This is a circuit board for an LED head light flashlight. It has a hi, low, and stobe feature. I would like to disable the strobe feature. I am an amature, please help.
  16. sr13579

    What is wrong with my transformer output?

    The thing is, I was trying to regulate a 220V-9V to 5 volt. I did it though. Everything was right.I was trying to make a dark sensor with NOT gate () The settings are good. But it wasn't working fine with the AC to DC adapter.( It is working fine with a battery like the video). The thing is...
  17. Lord_Nikon

    Help Please! 8x8 RGB LED Matrix with MAX 7219 and Arduino

    Hello all, I'm in the beginning stages of a project and am just learning how to use an Arduino Uno with a MAX7219 driver with an 8x8 LED RGB Matrix. I'm using someone's source code to just get a basic understanding of how to put all these pieces together and will then modify it as I need to...
  18. D

    Photodiode current measurements

    I am trying to build transconductance amplifier circuit to obtain values of the reverse biased photodiode (PD) current in order to estimate some of the LED characteristics. At first, I have used the scheme named “Recommended Zero Biased Circuit” from page...
  19. C

    But can an an LED do THIS?

    Non-technical guy, here. Trying to learn for a project I'm doing... A kids' nightlight. Need a low-power, surface-mount LED with three color settings and a fourth setting that cycles smoothly through the color spectrum. I ALSO need to be able to dim and brighten. Can anyone point me in the...
  20. J

    I need to build an LED strip to replace a 25W CCFL tube

    Im working on building LED strips that can be used in wacom cintiq 24HDs to replace the CCFLs when they fail because its not possible to access the lights , remove and replace, then close the monitor up again, plus the high voltage insulation isnt insulating properly, and the cherry on top is...
  21. WHYnot86

    Design assistance needed - Bluetooth controlled LED

    Hi, I am looking to build a Bluetooth controlled LED circuit. There must be 4 separately addressable LED arrays each with driver to control current. A battery, charger and protection circuit. A sensor to measure distance from the LED's to the surface they are lighting up. A sensor to measure...
  22. atferrari

    Display with LEDs - What technique to use?

    I am planing to create kind of a display with LEDs. Round or square, the board's expected size could be around 30 x 30 cm. LEDs' position is not expected to change; just the programing of the driver. Number of LEDs expected to be, most probably, around 64, laid in straight lines. Accuracy of...
  23. V

    [Help] 555 IC Keeps Blowing Up

    Hi, I'm new to circuits and electronics stuff, so kindly help me to solve the issue. I'm trying to add led DRL to my car, everything is working well if I power my circuit with 9V battery, but if I connect it to car battery after 3-5 seconds it getting blown. I have no idea why it's happening...
  24. J

    Need a regulator to power 700ma LED from 900ma constant current driver

    I know it seems silly but this is about being economical. Im comming up with a reliable solution that can be implemented by someone who is not particularly skilled. Although i myself have the same issue, i intend to build a driver which makes use of the monitors brightness PWM signal. Is...
  25. DannyDilla

    74HC164 + ULN2803 LED CHASER

    So a buddy of mine (Hi Bernard!) on another forum suggested I use a shift register for an idea I had. A little background--I'm pretty fresh out of college and I work with high voltages all day; mainly analog power, PCB Design, soldering, Hi-Pot and UL Certification. Digital Electronics is...

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