Cracker Box Amp
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WHAT WILL YOU MAKE?
WHAT WILL YOU NEED?
- 1 capacitor 0.047µF
- 1 capacitor 0.01µf
- 1 capacitor 100µf
- 1 capacitor 220µF
- 1 resistor 10Ω
- 1 battery connector
- 1 toggle switch SPST
- Cracker box, or similar
- Battery 9V
- Hook-up wire 20- or 22-gauge solid core
- 1 prototyping PC board
- Speaker 8Ω impedance
- 1 mono phone jack 1/4’
- 1 IC socket 8-pin DIP
- 1 potentiometer 5KW audio or log taper
- Rheostat 25-ohm 25W
- Audio amplifier chip LM386N
- Soldering iron
- Wire cutters
Solder the socket
Start by soldering in the socket to the board. Make sure the circular notch in the socket is facing towards the top of the board.
Solder the main board parts
Solder in the resistor followed by the capacitors and then the power lead.
Add the jack
Solder wires to the input jack and then the jack to the board. Give yourself about 6 inches of wire to work with to make it easier to put in the box later.
Add the pot
Solder wires to the potentiometer (pot) and then the pot to the board, leaving extra wire this time, too.
Solder the rheostat
Solder the rheostat to the speaker and add wires to go to the board. Again, leave some extra wire.
Add the chip
The leads on your chip as they are shipped are bent out slightly. We need to bend them in so that they’re perpendicular to the body of the chip. Gently squeeze them evenly to bend them in. Then push the chip into the socket, lining up the circle in the top of the chip with the circle in the socket.
Put holes in your box
Use your soldering iron to poke holes in your cracker box for the input jack, pot, rheostat, and a group for the sound out of the speaker. Use a pair of scissors to expand the holes so they are large enough for the posts and jack.
Put it all together
Remove the hex nuts from the jack, pot, and rheostat. Put all the electronics in the box, and then push the shaft of the pot and rheostat out of the holes for them and the end of the jack out of its hole. Screw the hex nuts back on to secure them in place.
Add a battery, plug in your axe, and get ready to rock!
A cracker box is nice, but why not kick it up a notch by building a better enclosure? Add piezo pickups to buckets and random objects to turn them into instruments. If you really want to rock, you can build your own effects pedal to get some heavy guitar sounds out of your amp.
Your safety is your own responsibility, including proper use of equipment and safety gear, and determining whether you have adequate skill and experience. Power tools, electricity, and other resources used for these projects are dangerous, unless used properly and with adequate precautions, including safety gear and adult supervision. Some illustrative photos do not depict safety precautions or equipment, in order to show the project steps more clearly. Use of the instructions and suggestions found in Maker Camp is at your own risk. Make Community, LLC, disclaims all responsibility for any resulting damage, injury, or expense.
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