Hi, this is Wayne again with a topic “Cracker Box Amp”.
Whether you want to practice in your dorm or play for a small audience practice, amps are great tools to have this outstanding little amp is cheap to build and there’s plenty of opportunity to express yourself with the box that doubles as your enclosure. The amplifier itself is a solid state circuit, built with the lm386 integrated circuit or ic. The whole thing is powered with a nine 9-volt battery. You’Ll need the following parts to build this project, all of which you can acquire at your local electronic supplier.
You’Ll also need some basic soldering tools: okay, let’s get started mount the ic socket to the pc board and solder. It in place then connect the .01 microfarad capacitor from pin 2 of the ic to a proto row on the pc board solder. The two wires of the 9 volt battery clip to the power and ground rails in the center of the board and then mark their polarity, connect, pin 5 of the ic socket to a proto row using the 10 ohm resistor and then use a 0.047 microfarad capacitor To connect that same row to the ground, rail connect, the signal terminal of the phono jack to the other leg of the .01 microfarad capacitor and the ground terminal to the ground.
Rail. Using two lengths of hookup wire cut the red lead of the battery clip and solder. The switch in line connect the right hand terminal of the 5k potentiometer to pin one of the ic socket and the center terminal to pin eight bridge the power and ground rails. Using the 100 microfarad capacitor making sure that the longer lead of the capacitor is on the power rail solder. The positive lead of the 220 microfarad capacitor to pin 5 of the ic socket and connect the other lead to a proto row. Connect this row to the right terminal of the 25 ohm rheostat.
The center pin of the rheostat connects to the positive terminal of the speaker now connect the ground of the speaker and the ground rail of the circuit to the left terminal of the riostat. If you haven’t already insert the lm386 chip into the ic socket taking care to orient it correctly, there’s just three more connections to make using short pieces of jumper wire connect, pins, three and four of the ic to ground and then connect pin 6 to the power Rail, the circuit is now functionally complete, so it’s a great time to plug in your guitar and a 9 volt battery to test it out once you’re happy with its functionality, we’ll install it in the cracker box enclosure, since our soldering iron is already hot, we’ll just Use it to burn holes in the box, so we don’t need to cut any make three holes on one side of the box for the potentiometer. The rheostat and the phono jack then make an array of holes in the front that will function as our speaker grille.
Finally, make one final hole for the power switch, mount the potentiometer, rheostat and phono jack and then place the circuit in the box, use some hot glue to attach your speaker to the inside of the grille and, lastly, install the power switch. Your cracker box amp is now complete and ready to rock. You can use a variety of voltages to power the amp, it’s tough to beat the 9-volt battery for convenience and compactness, but you can get a cleaner signal with a 12-volt supply, either way.
You’Ll get a sound, that’s plenty loud to fill a room play around with different power sources, to see what works for you or build it into a more permanent enclosure, subscribe for more make weekend projects and share your cracker box amp. In the comments below you, .