Lately I've been working on a few analog audio circuits. I was sitting around admiring my finely soldered boards (sarcasm) and thought, "Hey! Why don't I put this crap in a box or something?" I looked around the house, but alas, there were no box-like objects to be found. I then proceeded to destroy my garage, and Voila! I found an old hollow book box, and this project was born.
You can pretty much do this entire project with the following items:
Tools:
Soldering Iron and Solder
Dremel Tool
Box Knife
Hot Glue Gun
Drill (optional but handy)
Components:
Hollow Book Box (I got mine at a junk store, but you can buy an ugly version here )
4-8 ohm 4" Speaker (I got mine from an old police radio attachment)
Speaker cover (left over from a car stereo install)
9-volt battery x2
Electrical Components:
Resistors:
2.2M ohm
1M x3 ohm
1k ohm
100 ohm
2.2k ohm(if using a power led)
10 ohm
Capacitors:
0.047uf x2
10pf
10uf
3.3uf (I used a 4.7 because I couldn't find a 3.3)
0.22uf
100uf x2
220uf
0.01uf
Other:
LM386
MPF102 x2
25 ohm Rheostat
5k Linear pot
100k audio taper
The components listed above will make the following boards (which I'll explain how to make):
Little Gem Amp Circuit (http://www.runoffgroove.com/littlegem.html )
and
Mini-Booster Effects Pedal (http://www.muzique.com/tech/miniboo1.htm )
You can pretty much do this entire project with the following items:
Tools:
Soldering Iron and Solder
Dremel Tool
Box Knife
Hot Glue Gun
Drill (optional but handy)
Components:
Hollow Book Box (I got mine at a junk store, but you can buy an ugly version here )
4-8 ohm 4" Speaker (I got mine from an old police radio attachment)
Speaker cover (left over from a car stereo install)
9-volt battery x2
Electrical Components:
Resistors:
2.2M ohm
1M x3 ohm
1k ohm
100 ohm
2.2k ohm(if using a power led)
10 ohm
Capacitors:
0.047uf x2
10pf
10uf
3.3uf (I used a 4.7 because I couldn't find a 3.3)
0.22uf
100uf x2
220uf
0.01uf
Other:
LM386
MPF102 x2
25 ohm Rheostat
5k Linear pot
100k audio taper
The components listed above will make the following boards (which I'll explain how to make):
Little Gem Amp Circuit (http://www.runoffgroove.com/littlegem.html )
and
Mini-Booster Effects Pedal (http://www.muzique.com/tech/miniboo1.htm )
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Signing UpStep 1: Circuitry!
The basis of this amp is two simple audio circuits.
*Remember that it's always easier to breadboard a circuit first. On audio circuits you can exchange capacitor size values for different tonal and reactive effects*
First, assemble the mini-booster schematic found (here ).
Below you'll see that I've posted the vero board layout for both. I'm sure my layout isn't the most efficient or compressed, but it does work. Make sure that you leave yourself plenty of wire on all your external leads. This will be handy for moving the boards around inside the hollow book.
Next, assemble the "Little Gem" schematic. This is the simpler of the two circuits. You can look (here ) for more information.
*note* On my veroboard layout below, you'll notice some red scribbley lines. This indicates where you need to sever the trace on the board. You can also test each individual circuit since they are individually powered.
After the assembly of both circuits, simply attach the output of the mini-booster to the input of the little gem. You can cut the ground wire from your 9v batteries and attach both ends to an On/Off switch (pictured below) The two battery grounds to the 'OFF' and the two board grounds to the 'ON' of the switch.
The complete circuit can be found (here ).
*Note on the Pots* The 25 ohm Rheostat acts as a volume control (knob 1), while the other to pots act as gain controls for the individual circuits.
*Remember that it's always easier to breadboard a circuit first. On audio circuits you can exchange capacitor size values for different tonal and reactive effects*
First, assemble the mini-booster schematic found (here ).
Below you'll see that I've posted the vero board layout for both. I'm sure my layout isn't the most efficient or compressed, but it does work. Make sure that you leave yourself plenty of wire on all your external leads. This will be handy for moving the boards around inside the hollow book.
Next, assemble the "Little Gem" schematic. This is the simpler of the two circuits. You can look (here ) for more information.
*note* On my veroboard layout below, you'll notice some red scribbley lines. This indicates where you need to sever the trace on the board. You can also test each individual circuit since they are individually powered.
After the assembly of both circuits, simply attach the output of the mini-booster to the input of the little gem. You can cut the ground wire from your 9v batteries and attach both ends to an On/Off switch (pictured below) The two battery grounds to the 'OFF' and the two board grounds to the 'ON' of the switch.
The complete circuit can be found (here ).
*Note on the Pots* The 25 ohm Rheostat acts as a volume control (knob 1), while the other to pots act as gain controls for the individual circuits.
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(in terms of conductivity, heat, fire safety, etc)
The writing that is linked gives the correct addresses, but both of the hyperlinks are to the mini-boost effects pedal.
Good instructable although i would like a little more description about assembling the circuits- what all the pots do etc. because there is almost a little too much information at those linked sites for beginners like me, although i did quite a lot of research into mini amp circuits when i wanted to build one earlier this year.