Some time ago, we stumbled upon an article in Craftzine Magazine that showed how to make a simple iPOD dock with relatively few and cheap parts(Volume 7). Right before Thanksgiving, I got Arianna interested in building it. Aaron also helped out. Adam was the project chef. Here’s a little picture progress book.
This is the little tiny circuit board we got, with the chip on it. The chip is shown on the wrong side of the board! Yes, we messed up the first time…
Arianna asked what all the colors on the resistors mean, so, naturally, I showed her. Every time we needed one, she insisted on selecting it with the color chart all by herself. Here she is deciphering the resistors with a nice color chart I found on the web.
I have a multimeter that we put to good use for this project. Arianna asked what that was for, so again, I showed her. Then she wanted to check to see if the resistors she picked out were the right ones. And you know what? She never got them wrong! I have a variety pack of resistors, and Arianna deciphered them and then measured them all, so now they are labeled for future use. But she developed this important ritual before using the multimeter: ALWAYS put the probes to your head and make a monster noise(and grimace) before putting the probes to the component:
Here’s a shot of her and Aaron(note: no eyes were harmed in taking this picture) stripping a wire:
After learning how NOT to use the wrong side of a circuit board, I dug out a breadboard I bought, jeez, about 20 years ago. This turned out to be quite fun, as Arianna insisted on hooking all the wires up. In doing so, I taught her how to read the wiring diagram for this project, and how the breadboard works, so she could determine where to put the wires so components were connected properly. In this picture, you can also see the switch she picked out from Radio Shack. Know why she liked this one? Because it came with four different color covers for the lever! This she changed every five minutes, until she settled on red. Apple, tree…
After we bent a couple of leads and wires, she started using the needle nose pliers to push things into the breadboard. You can see a little bit of the wiring diagram, too:
Okay, this picture need some explanation. Once we knew that we had to put the parts on the bare side of the board, we needed to keep track of the copper traces on the other side of the board, which we kept face up. So, Arianna maneuvered herself under the board like an auto mechanic, and put the wires and parts through into the right places. On her back. Every time.
Usually, I held the soldering iron, and Arianna applied the solder. She became very good at it, making no blobs or short circuits. But since I couldn’t do this and take a pictures, we staged one afterwards. She is holding the iron to a pin bent onto the copper trace, and applying solder. If it looks like she knows what she’s doing, it’s because SHE DOES!
She picked out this little black box to put the finished circuit in, but we had to make holes in it for The Switch and a couple other things that needed to poke out of it. Usually, we used the hand drill, but plastic tends to grab the bit, so we used the power drill that Grandpa Paul gave me for Christmas some years back. You can hear it coming, can’t you? “I WANNA DO IT!!!”
Here is the inside of her work, showing the simple circuit and battery that takes to run the thing. And an adoring engineer/builder, inspiring the title of this blog entry:
The finished product! We designed the jack to stick out the side of the box, so you just have to impale your iPOD onto the box, no cables required. Instead of the wimpy tiny speakers that Craftzine recommended to use, I found some car speakers leftover from the Villager(when I upgraded to Pioneer three-ways). I was surprised at how good they sounded, and Arianna was certainly sold on them. Therefore, we put speaker connectors so the speakers and box can be moved around independently. We’ve got ideas about building a cabinet for the speakers(now Aaron wants one JUST for his idea, which we will write about later, if we build it), but we need to build a second amplifier circuit for the other channel. There’s room in the box, and extra posts on the speaker terminals…
The project is a tiny amplifier built around the LM386 chip. We got all our parts from Radio Shack, but there are two problems with the Craftzine plans:
- You cannot connect two 8 ohm speakers to a single LM386 chip
- You need a 10uF capacitor across the 9V battery to prevent distortion
Aside from that, this thing CRANKS!