LED Beginner project: part 1

Written for beginners by a beginner. This project is my first project using LEDs, and I have documented it to present it to the world. I mounted two green LEDs in a sign that I could hang in my bathroom to solve certain...ahem..."problems."

Step 1 Materials

This is the list of parts I used in my project. All electronic parts were bought from Radioshack. If you can stand to wait, order some parts online. Radioshack has an absurd markup price. I went there because I'm an impatient teenager, and I wanted to do the project NOW. I am using a potentiometer because i wanted to be able to dim the LED, and a switch to turn it on and off.


-A two pack of green LEDs (part number 276-304)
-a SPST (single pole, single throw) toggle switch (part number 275-612)
-a 10 ohm resistor. I just had this lying around.
-3 AA batteries
-a 5K audiotaper Potentiometer (part number 271-1720)
-random pieces of wire that I had lying around.
-an "aquired" sign.
-a soldering iron

Comments

[sci4me]

Why do you have a potentiometer?

[dinesh gupta]

potentiometer is used to increase or decrease the light of LED

[sci4me]

o. :D

[agis68]

Guys take it easy, It's true, in Technical University they told us that is dangerous to solder on batteries. But I did it so many times I forgot the number. Iam 42 and I am doing this for 22 years. Nothing happened ever to me or any other technician I know. The secret it's one....Yes you can solder on batteries, but very quick and shortly.

[DELETED_jorgegunn]

Ive done it too but anyone is skeptical they can just buy a batery holder or tear one out of a broken toy.

[zeero360]

mst u guys r lucky i cant buy LEDs

[Shifrin]

Why Not???

[zeero360]

i checked all the hobbie shops and nothin i dont no where else to check u got any ideas

[drbill]

Might find some in the dump or on junk by the wayside if all else fails.

[Shifrin]

Okay,
If you have a Paypal, you can order of the internet from one of the two stores:

http://www.radioshack.com/search/index.jsp?kwCatId=&kw=led&origkw=LED%20&sr=1

http://www.sparkfun.com/commerce/categories.php?cPath=51_89

If you have a Radio Shack near you, you should go there, here is a store Locater:

http://www.radioshack.com/storeLocator3/index.jsp?clickid=rsk_header_storeLocator

I Hope I helped.

~Alex

[BillVT]

Please note: soldering to a battery is an excellent way to heat up and potentially cause an explosion. It is best to use electrical tape or some other adhesive rather than solder directly to a battery terminal. Be Safe rather than Sorry and covered in an acidic mess!

[Doubleblades85]

w00t acidic messes :D ugh not fun to get Battery acid in your eyes o.o

[red-king]

yeahhhh... its not really a good idea to solder to a bettery...

[PyroMonger]

why would you need a pot for this circuit? I don't see a need for dimming the leds

[Gamernotnerd]

Code for falstad circuit simulator (http://www.falstad.com/circuit/):
$ 1 5.0E-6 382.76258214399064 50 5.0 50
v 336 272 336 256 0 0 40.0 1.5 0.0 0.0 0.5
v 336 256 336 240 0 0 40.0 1.5 0.0 0.0 0.5
v 336 240 336 224 0 0 40.0 1.5 0.0 0.0 0.5
s 336 224 336 176 0 0 false
174 368 160 304 160 0 5000.0 0.9950000000000001 Pot. Position
r 304 160 240 160 0 10.0
162 240 160 240 224 1 2.1024259 0.0 1.0 0.0
162 240 224 240 288 1 2.1024259 0.0 1.0 0.0
w 240 288 336 288 0
w 336 288 336 272 0
o 5 64 0 35 0.3125 0.025 0 -1

[sasuto]

Yeah REALLY BAD IDEA to solder battery or any other kind of engery sources.

[ilovelorie]

Thanks for making this tutorial. I didn't know where to look to start learning this and everything seems so advanced. I plan on putting some LEDs on one of my art pieces and i needed it to blink so I will go slow and keep up with your lessons. :) thanks much

[electronic nut]

either i'm now thinkin today or i'm right because i'm pretty sure there is no such thing and no reason as a 10 ohm resistor

[flare765]

nice im gonna try something like that

[Patented]

is the potentiometer is only for the look?I don't understand

[Rokko8652]

Close, the knob is for looks, the pentiometer is a variable resistor that makes the LEDs brighter or dimmer.

[Patented]

Nice, thank you!

[Rokko8652]

You're welcome.

[Gamernotnerd]

Flushing? *Pshaw*

[zachninme]

Why not use a pizeo transducer to pick up on the loud flush, and then shut off after that? Simple flip-flop chip should do the job!

[James (pseudo-geek)]

nice idea! I think it would be mroe affective to use a switch inside the toilet on the flushing handle tho (be sure not to get it wet)

[stringteary]

here's the new url:
http://metku.net/index.html?path=mods/ledcalc/index_eng

[mr bkilled]

sorry to tell you this but the link that you posted has changed and that page does not exist anymore so you should think about changing it

[zhdai]

Very nice site!
http://www.eefl.cn
http://www.cn-ovl.com
http://www.slim-lightbox.com
http://www.rondeflower.com
OVL-Good ccfl,eefl, ccfl ring, ccfl PC kits, sound controller, Lightbox, El-panel, Backlight materials inverter supplier

[richjd]

I like your LED project. May I suggest that you add aschematic diagram. As a beginner in electronics you could learn much by drawing one. Great stuff...... richjd

[eight]

Personally, I think a 12v inverter (as used in a CCFL) connected to the metal urinal and step would negate the need for a LED. The audible signal could be heard for many kilometers :P 'Scuze my dry sense of humour. It's an Aussie thing ;) Great post ! - eight

[jgrimes227]

Simple! But thats because you did an awesome job on the instructions. GREAT JOB. I wish only a few of the adults on the Corvette Site I belong to could explain things as clearly and completely as you have done. I really like the idea one guy had of adding a motion detector to trigger the Flush lights - now how about one for put the g---damned seat up!! and Wash your hands. The only problem I see is naming your yacht after you have made a fortune selling these things restaurants and other public bathrooms.

[sharpdust]

If the wires from the switch (each post I mean) are touching eachother will the switch become useless? If so, is it possible to completely just get rid of the switch and just use the potentiometer? I would try it myself, but I just completed the project and I basically have a crap load of electrical tape everywhere (I didn't try soldering because I suck at it) and I want to make sure it would work that way if I did it.

[JethroWho15]

how come when figuring out which resistor you need and you used the led caculator you said you nedded a volate drop to 2.1 I though you only neede a voltage drop to 4.2 because there are 2 led's

[FlawlessCowboy]

Sweet sauce! I just finished making mine. This is my first soldering project. Thanks much for the directions and idea!

[bustersdad]

Thanks for the info on the calculator. I have wanted to "play" with LEDs for a while but that math piece was getting in the way. With this information in hand I think I can do it. Thanks again!

[cyenobite]

great instructable and for a beginner like me I think I can follow this one!
AND you made the MAKE blog!
http://www.makezine.com/blog/archive/2006/04/led_beginner_project.html
Thanks for posting
Cyen
http://cyenobite.blogspot.com

[Willd]

thanks for the correction Invisible!

[cybervanig2000]

I'm a reeeeeel beginner at this electronics stuff. so a simple project like this helps me learn a lot. Thanx a bunch.

[HapHazard]

Put a timer and a motion detector on instead of a switch -- now that would be freaky! ;-) This is a good intro to show how to add LEDs to projects! Keep up the instructables! -Matt