LED "Name" Switch Toy for Toddler

I made this toy a couple years ago when my son was 2. He's always been fascinated with lights and switches. In an effort to keep him entertained and perhaps learn the letters in his name, I built this simple toy.

Used Parts
- about 50 LEDs (RED, Orange, Green)
- LM7812 Voltage Regulator
- Power source (I had an extra 15v wall wart in my junk bin)
- Power jack (N-size, radioshack)
- Wire
- Scrap wood (Oak)
- Various switches (I had laying around, you can find good deals on ebay)

Remove these ads by Signing Up

Step 1: Create Template

My first step was to create a template to work from to aid in drilling the holes for the LEDs. I'm a hack with photoshop but was able to come up with something simple to use as a guide when drilling the holes to accept LEDs.

astromoe99 says: Jul 17, 2012. 7:32 AM

I loved this project and used it as my first real electronics project. Thanks for a great idea!

I made mine using 6V from 4AA. The LEDs I bought were very bright and I didn't want to blind the little guy, so in order to dim them I put higher resistance on each series of LEDs than Ohm's law would dictate. In case of the green I used no resistance because the voltage drop and inherent resistance across 3 of them dimmed them to the level I wanted. 6V meant a LOT more soldering but I wanted the box to be portable.

Trevorstach in reply to astromoe99Jul 20, 2012. 4:59 PM

I know you have just finished the project, but do you have any idea how long the batteries last? I want a portable one too, and as long as they last for several hours, I think I would likely follow your lead on using a battery setup

henlij (author) in reply to astromoe99Jul 17, 2012. 1:12 PM

Excellent. I'm happy others found this a worthwhile project. Hope Cooper has a great time with it. :-)

astromoe99 in reply to astromoe99Jul 17, 2012. 7:33 AM

The first post didn't take my images.

astromoe99 in reply to astromoe99Jul 17, 2012. 7:34 AM

Ok I apparently can solder but not work image uploading on Instructables :)

IronWill says: Jul 4, 2012. 7:59 AM

Creative. it is cute.
is it just me but all toddlers are named Elliot? :D it is not the first nor the third instructable dedicated to a toddler Elliot.
hope he liked it! :)

Shxdxws says: Jun 25, 2012. 1:08 PM

If you can help...

I'm building a similar project for my son to play with. Mine uses 3 LEDs (Red, White and Blue) and 3 switches. Each switch is supposed to turn on one light, and they are supposed to each work independently, but run off of the same power source (9v battery, likely). I can't seem to get the wiring right, and I was wondering if you could help. The LEDs I'm using are these:
http://www.radioshack.com/product/index.jsp?productId=3125355
http://www.radioshack.com/product/index.jsp?productId=3111495
http://www.radioshack.com/product/index.jsp?productId=3096133
I need to know how to wire them to make them work independently with their respective switches and what value resistors to use (and where to put them for that matter). The total voltage requirement for all 3 on at once should be about 8-8.5v, so a 9v battery should work. I'm not worried about changing it out when it's dead, I just want this to work! I'm usually pretty good with electronics, but this one is driving me nuts! Thanks in advance for any help...

henlij (author) in reply to ShxdxwsJun 25, 2012. 2:21 PM

There are some handy LED/Resistor calculators online, just google "LED Resistor calculator". Using one, I've determined that you'll want 3, 330 ohm, 1/4 watt resistors. Attached is a schematic as best as I can tell from your description.

Good luck and have fun! :-)

Screen Shot 2012-06-25 at 4.16.06 PM.png

Shxdxws in reply to henlijJun 25, 2012. 4:44 PM

PS - what do you use to make your schematic drawings? Is that a dedicated program or do you just use an image editor like Photoshop?

henlij (author) in reply to ShxdxwsJun 26, 2012. 6:01 AM

I use a program called iCircuit (for Mac OS and iOS). Very simple and doesn't do as much as others but for someone at my skill level, it is perfect.

Shxdxws in reply to henlijJun 25, 2012. 4:42 PM

Thank you so much for your time...my only question is that wouldn't the resistor values have to be different since the FV on each LED is different? I couldn't find a resistor calculator that let you put in more than one LED voltage, so I wasn't sure if this would work. I'll give it a shot though and let you know how it goes!

Shxdxws in reply to ShxdxwsJun 27, 2012. 7:06 PM

Thanks again for your help...It works! Not shown: I had to cut out a piece of old sponge and glue it to the back plate to hold the 9v in place so it doesn't rattle around, but here's some (sideways?) photos. Oh, and the boy loves it too!

henlij (author) in reply to ShxdxwsJun 28, 2012. 6:31 AM

Love it. It's a lot like the first one I built. Watch out though, if your boy is like mine, he'll grow tired of it and then you'll be making another one more complicated. ;-)

After I built the one spelling his name and he got tired of it, I just broke down and bought him a set of "snap circuits". He LOVES them. Cheers!

henlij (author) in reply to ShxdxwsJun 26, 2012. 6:04 AM

Yes, you'd think they'd need to be different, I'm not entirely sure why! Play around with some values in that 200-400 ohm range and see what they LEDs look like. I did fiddle with values a bit on mine so they different colors would be close to the same brightness.

Trevorstach says: Jun 15, 2012. 11:11 PM

Hi, I love this and I have ordered the led's for the project. My little guy is so busy and mobile it would be convienant to have batteries for this project, but drawing ~1 amp, how long would a set of batteries last? I was also thinking I could do it with the option for batteries or a wall wart. Any thoughts?

henlij (author) in reply to TrevorstachJun 21, 2012. 9:19 AM

Sorry for the delay in getting back to you. I don't think batteries would last very long given my calculations. Drawing an amp, AAs would only last about 2 hours or so. :-(

jdmolson says: Mar 9, 2012. 7:03 AM

This is a great idea ... thanks for the inspiration Henlij! I will definately be making one of these for my daughter who is 21 mos. and who's favorite word right now is "buttons"!

B_randon says: Jan 18, 2012. 7:52 PM

Exactly how many volts are you running on? I'm thinking of using battery holders, but wasn't for sure if it would be easier to use a power supply.

henlij (author) in reply to B_randonJan 18, 2012. 8:56 PM

I'm running the circuit at 12v (via 7812 regulator). There are about 50 LEDs so the current is ~1amp. You could use batteries but I try to avoid them if possible. Even recharging them is a pain!