Help with a learn to solder project using infrared LEDs

Hi, Recently my company remodeled our EE lab and was going to throw out a huge amount of electronic components, since they didn't care I took all of them instead.  Next spring I am likely going to teach a small class on basic soldering. I can solder well enough to teach others, but I can't design circuits at all. I'm looking for some kind of project that could use some of the parts. The coolest parts are infrared LEDs and Phototransisters. I have thousands of these

Fairchild QSC113 and QEC122

I also have around 30 small piezio sounders/buzzers no part number
A couple hundred red and green short leg LED (Can't do a cube matrix as the legs are short for a angled board level mount)
Lots of small switches
I know I have 3904 transistors as well as many other flavors but I don't have the numbers in front of me
I also should have any small caps, resistors, diodes, and zener diodes
I know I also had several 555 timers and lots of resonators and crystals in various speeds

Circuit goals
Through hole only No Surface mount
Able to be made in 1-2 hours by new solderers
Class will be limited likely to less then 10 attendees depending on # of soldering irons I can find
Circuit has to do something with an effect like sound or light so they feel like they created something
I would like any extra costs to be under $40 for the whole class as I will likely have to pay for it
Each circuit needs to be able to be taken home
Ages will be from about 14 to 75+

I do not have have most of my extra parts sorted but I do know a general "type" of the parts so feel free to use a part and I'll see if i have something similar.

If I like your circuit I'd be glad to send you 250 of each of the infrared LED/phototransiters

The class will be taught at Hoosier Recreation Workshop


nevets_mcd (author) 4 years ago
Thanks for the ideas so far, it will be a little bit before I can explore these options. Keep 'em coming.
lewisb424 years ago
Just a general suggestion is to look into the Beambots stuff for ideas.

Another: IR LED's can be "seen" by most digital cameras. Some people have suggested using them to foil face-recognition cameras by mounting them to eyeglasses. Might be a fun and instructive project (have students look at the IR LEDs through their phone cameras to see how they work).
You don't have to build a usable item when learning to solder. It's a good idea to start on something that doesn't have to work, Then you can also practice de-soldering those components.

Look up 555 timer circuits. You can do a lot with 555 timers, a couple of cap, resistors and leds.