I am working on a project N/T that will be using LED lights, and an engineer at work pointed me to this site to help calculate the resistor needed for a specific LED. Thought it might be useful to others.
http://led.linear1.org/led.wiz
Bob C.
Bob Cope said:
I am working on a project N/T that will be using LED lights, and an engineer at work pointed me to this site to help calculate the resistor needed for a specific LED. Thought it might be useful to others.http://led.linear1.org/led.wiz
Bob C.
Bob - some years ago I did a workshop on using LEDs for our local club - my notes included five different ways to determine current limiting resistors - have a look:
http://davebodnar.com/railway/LED_light_project/#Selecting_Current_Limiting_Resistors_
dave
Welcome Dave,
Some very useful information you have provided.
I also enjoyed the video of your GRR. Pretty big trestle you have there 
Ralph
Ralph Berg said:Thanks, Ralph - there is more LED related info here:
Welcome Dave, Some very useful information you have provided. I also enjoyed the video of your GRR. Pretty big trestle you have there :) Ralph
http://www.trainelectronics.com/articles.htm
Just scroll down to the LED Related Articles (shown below)
dave
LED Related Articles:
A Simple Constant Brightness LED
LEDs 101 - Introduction & Overview
LEDs 102 - Using them Onboard Trains
LEDs 103 - Turning them On and Off
LEDs 104 - A Better Constant Brightness Circuit for LEDs
Multi-Function Crossing Controller (NEW!)
A Lighting System for Mr. Rogers Trolley (drilling LEDs)
Ditch Lights Article
Mars Light Article
Lighthouse Beacon
Morse Code Flasher
LED Lighting with Larger Solar Panels
LED Signal Lights for LGB Switch Motors
And Dave I’ve used your LED articles for some of my own trains. Great info with easy to follow guides for the beginner. And our favorite PICTURES.
Dave Marconi said:It is good to hear that they have been of use to you..... sometimes you put things out there and wonder if they are being seen!
And Dave I've used your LED articles for some of my own trains. Great info with easy to follow guides for the beginner. And our favorite PICTURES.
Thanks, Dave!
dave
L.E.D.s are cool.
Dave B.
Thanks for the look at the link. I do seem to remember some articles on LSOL (which I no longer subscribe to) that were very informative and well written. Even a non spark jockey like me could follow and understand the basics. That was something one of the PE’s at work pointed me in the direction of, and I felt it might find some use here.
Welcome aboard our merry band.
Bob C.
Thanks for posting them. It’s great when information is shared. … And welcome aboard Dave
Dave,
Are any of your products ready built and available for sale.
I’m interested in the Mars light for the FA or PA.
John Bouck said:John - most of the things on my web page are available as kits or wired and tested units. Unfortunately I am out of the Mars light circuit boards and have no plans to reorder them in the near future - I have moved to a different circuit board manufacturing company and I need to redesign each circuit board for the new company and I have yet to do the Mars light.
Dave, Are any of your products ready built and available for sale. I'm interested in the Mars light for the FA or PA.
It is one the “list” but may not be done for several months.
dave
I can wait. We won’t be running until the snow melts.
I’ll check back from time to time.
John Bouck said:Good morning, John - I worked on the new design for the Mars light board over the weekend and ordered the boards yesterday. They should delivered by the end of the month. Drop me a personal email ([email protected]) if you are still interested in ordering one.
I can wait. We won't be running until the snow melts. I'll check back from time to time.
thanks!
dave
When you use an LED driver, you don’t need to calculate anything. I’ve use LED drivers on my track powered LED power supply. Thanks to Dave, I’ve got printed circuit boards for them. It only takes three components to make one and will power at least 15 LEDs.
Dick Friedman said:I believe that the devices that Dick is referring to are CL2N3's - the article that describes their characteristics and how they can be used to supply constant current to LEDs is here:
When you use an LED driver, you don't need to calculate anything. I've use LED drivers on my track powered LED power supply. Thanks to Dave, I've got printed circuit boards for them. It only takes three components to make one and will power at least 15 LEDs.
http://www.trainelectronics.com/LED_Articles_2007/LED_104/index.htm
It is titled A Better Constant Brightness Circuit for LEDs
dave
Got a chance to use my pc boards for the constant current LED power supply today. Took about 20 minutes to build, and about four hours to shoot the trouble out of it so it would work. I think the next one may take 30 minutes to build, but maybe no trouble shooting!
I wired the bridge rectifier backward, and had to cut it out and use a second one. Had to be careful about the capacitor polarity. I got it right, but afterward noticed that the pc board shows a printed square for positive polarity for both the rectifier AND the capacitor. Works fine now. I had it cooking for about 90 minutes!
Thanks again David.
Good deal on getting things to work, Dick! Trouble-shooting is part of the deal when you work on projects like this - one needs to love working with puzzles and sometimes you just need to walk away from it for a few hours or days to allow the solution to rise to the top of your noggin!
I hope you continue to design & use circuit boards - it is amazing how useful that skill can be!
Enjoy!
dave
Good to see you back from China Dave!
I hope you knee is feeling better.
Paul Norton said:
Good to see you back from China Dave!I hope you knee is feeling better.
It is good to be back in the good-old-USA - kind of scary having surgery in Shanghai!
The good news is that both knees are on the mend and I expect to be able to do the scheduled presentation at the National Convention in Chicago this summer…
thanks!
dave