It is my first instructable.Lets see how to make an audio amplifier which you can use with any of your musical instruments like guitar,piano and with ipod and other devices.So Lets begin the journey....
Disclaimer: If following this guide anything damages i shall not be held responsible.Do it at your own risk.
You need the following components
1- LM 386 semiconductor (IC)
2- 100 micro Farad capacitor
3- 220 micro Farad capacitor
4- 10 ohm resistor
5- 5 kilo ohm variable resistor
6- 100 ohm variable resistor
7- 0.01 capacitor
8- 0.047 capacitor
10- 9V Battery clip
11- 9V Battery
12- 3.5mm stereo jack male
13- 3.5mm stereo jack female
14- Project board (or you can use dotted board and solder)
You can find these electrical components from your nearest electronics store.These all components are easy to find and are common so you won`t have a hard time to find it.
Placing the IC
1- Place the LM 386 in the project board as show in the image.
2-If you pick the IC in front of you (so you can read what is written on it) then the lower left pin is 1 and the pin number increase anticlockwise.Take a wire and join the 3rd pin to 4th pin(GND pin).
Join the one pin of 0.01 capacitor with the 2nd pin of IC. The other pin of the capacitor should be joined with the INPUT.
4-Now join the 1st pin of IC with the A pin of the 5 k ohm variable resistor.
Join the A pin of this variable resistor with the C pin.Lastly join the 8th pin of IC with the B of this variable resistor. This becomes the GAIN.
10 ohm resistor & 0.047 capacitor
6-Join the 5th pin of IC with one side of 10 ohm resistor, the other side of the resistor should be joined with the one pin of 0.047 capacitor. The second pin of the capacitor should be joined with the GND pin (4th pin of IC).
7-Now again join the 5th pin of the IC with the +ve side of 220 micro farad, the -ve side of the pin should be attached with the A of the 100 ohm variable resistor.The B pin of the variable resistor should be connected to the GND pin (4th pin of IC).This becomes the Volume controller.
Input and Output
8-Join the +ve pin of the 3.5mm stereo jack female with the C of the 100 ohm variable resistor.And the GND of the female jack should be attached with the GND of the IC (4th pin of IC).
9-Join the +ve of the 3.5 mm stereo jack male with the other side of the 0.01 capacitor and join the GND of the male jack with the GND of the IC.
Step 10: Testing
10- Last but not the least join the +Ve of 9V battery with the 6th pin of IC and -Ve of the battery with the 4th pin of IC.
Congratulation !!! you have made your own simple audio amplifier.
Now the time to check it out.Join the male jack with your mp3 player or musical instrument and female with the speakers.Now adjust the Volume and Gain to get the best and loudest possible sound.I should notify you that with this amplifier only one speaker will work.And do the adjustment from low to high.Do the adjustment carefully or it can damage your speakers.
You can change the input jacks as your requirement.You can add a 220 micro farad variable capacitor instead of simple 220 micro farad capacitor to change the bass.