Large Scale Central

LEDs for Dummies

General Discussion
#1

I am looking for an LED lighting for dummies type primer where I can curl up by the fireplace with a martini in hand and learn all about LED lighting as it pertains to garden railroading. I need to understand at a 5th grade level about diodes, cathodes, resistors, MRIs, EIEiO, and voltage. I would also include that I need to know how to integrate LED lighting in buildings, passenger cars and whether I can hook any of this up to my 12 volt garden light system…I would like a flicker effect with some lighting due to the era of my railroad…late 1800s - early 1900s…

Thanks for your suggestions…

Richard

#2

Richard - here are some articles I have on my web page that should give you some idea of what can be done -

dave

http://www.trainelectronics.com/articles.htm

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#3

You ask and somebody answers. That’s always been cool about this site.

#4

now Richard just has to move the computer near the fireplace…

#5

I buy my LED’s already wired and set up for 12 volts. Don’t have to worry about all the resistors, and such. I got tired of building them up for 12 or 14 volt usage.

Anything complicated, I had Dave Bodnar build them up for me.

#6

Thanks for the quick replies…Sounds like I might need to call Dave when I figure out all that I want to do!! Dave, thanks for the links!!

Korm, no worries about moving the computer by the fireplace…if I can pry my iPad away from my son I’ll use that. Oh…hmmm…guess I’ll have to figure out how to move my computer…

Richard

#7

Richard, not to take anything away from David, but look thru this store on eBay. This is where I get my prewired LEDs. and they have flickering or flashing as options.

http://stores.ebay.com/Lighthouse-LEDs?_trksid=p2047675.l2563

#8

Might be good to start learning with voltage, amperage, ohms law.

Greg

#9

E=I/R

P=EI

Yea Greg, learning just the basics would be a good idea.

#10

It been half a century since I took an electronics course.

Most of what know now, I learned here.

This one is saved in my knowledgebase under Greg’s Law. (http://www.largescalecentral.com/externals/tinymce/plugins/emoticons/img/smiley-smile.gif)

The sum of the voltage drops in a complete circuit must equal the voltage source.

Take the voltage drop across a device, multiply it by the DC amps, you

have watts. This power has to be dissipated somewhere and unless your

device glows like a light bulb, it’s all in heat.

#11

Paul, yea. Well electrons still behave, or misbehave, like they did half a century ago. Now we just have different components to frustrate them with.

And you are right with “Greg’s law”. And if you don’t plan accordingly, then too much voltage can be dropped on (applied to) a component.

#12

Hey Greg, you think you can teach an "Beginning Electronics for G Scale in your spare time? haha

#13

http://barefootelectronics.com/led001.aspx

#14

I’d love to teach a course (in fact I taught college physics and computer science)… but not much free time…

I need to make a video on how to navigate my web site first ha ha!

Seriously, there’s plenty of stuff on the internet, and, my opinion, once someone “gets” ohms law, and the important point Paul brought up, things seem to make sense, current limiting resistors for LEDs are just simple, series and parallel are no longer mysteries.

Greg

#15

I am just beginning to understand it all. My problem is I love to learn… I am not usually satisfied with hook wire one to slot A I want to know why I am doing it. Then instead just hooking stuff up and running it I am downloading PCB design software and Lear in to design circuits. Takes a lot longer but us much more regarding.

#16

I am under the impression that if you let a computer design a circuit, only another computer can understand it. When I look at some of the circuit boards in our trains, I wonder why the traces run all over the place on both sides of the board. After drawing them all out, they are just simple circuits twisted beyond recognition.

I use straight trace perf board for my projects: Super (PnP) Sockets, LED light boards with the dropping resistors as trace jumpers, Trigger Wire Interface Boards between receivers and sound boards with volume control components and if needed Bachmann chuff fixes. That way if something is wrong I can trace it, especially if it has screw terminals to place the voltage meter on.

My circuit design tool is Excel. I shrink a large run of columns to 1.5 to form graph paper. I can draw, copy, cut, paste, change colours, insert device pictures or shapes and resize them to fit. I just keep changing things until I have the neatest and easiest to understand circuit board. It even has artistic options if you want to get into shading, rounding, profiles, etc. When it’s all done I use the view menu to remove the grid lines. Then I copy the circuit board and past it into Paint to make an image of it for web site articles.

I save my projects as templates, so I don’t have to draw them from scratch; just cut and paste until I have what I need.

#17

The more traces a board needs, the more they cross paths and that is why they use both sides of the board.

This is like bridges and tunnels for traffic in a city.

#18

Dan Pierce said:

The more traces a board needs, the more they cross paths and that is why they use both sides of the board.

This is like bridges and tunnels for traffic in a city.

That’s correct Dan, but us old farts are stuck in the days before double and even triple sided (layers) boards. Back then you would cross a trace with a simple jump wire and it was pretty easy to follow. Not so much anymore as everything gets smaller and smaller.

#19

Well being a totally newbie to circuit boards I think you nailed it John. Things like jumper wires and resistors take up valuable space. To me the idea of a PCB (Printed Circuit Board, yes I clarified that because until about a week ago I had no idea what PCB meant, and others might suffer as well) is to eliminate space robbing wire. Otherwise why not just get a non printed circuit board and use all wire instead of the embedded traces. That is how they used to do it and it worked. But it was big. Now in most G scale we have some room to work with but I am now wanting to play with small little industrial locos and keep them RC battery. Bottom line space is a premium.

#20

Jumpers cost assembly money, cause reliability issues, and most stuff with microprocessors need multi layer boards now. IC’s are designed with pinouts so that busses (address, data, etc) can connect to each other without having traces cross.