Audio Power amplifier with speaker
An LM386 is the heart of this module. Simply connect power and a audio signal and presto! you can hear it! I did not realize how much I would like this module until I actually built it. The potentiometer adjusts the volume. Labeling pins from left to right:
Pin 1: Ground
Pin 2: Power (5 to 15 volts)
pin 3: No connect
pin 4: Signal
The schematic for this circuit:
Not much to it really.
I personally have used this to:
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test a guitar pre-amplifier |
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test a doorbell circuit |
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hook a microphone up to a pre-amplifier and let the kids talk into the microphone. its crazy how much enjoyment the children get from just hearing there own voice amplified! |
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make a radio by mistake! |
this circuit is really nice because anytime you want to HEAR something, you don't have to build another circuit on your breadboard, all you have to do is plug in the module, supply power, ground and the signal and you are done.
A simple idea for someone who does not own a scope. If you simply want to know if a signal is PRESENT, you can use the audio module as an "audioscope" of sorts. simply put an AC coupling capacitor on the input of the module and probe different parts of the circuit to HEAR the activity there. This can be a simple but effective troubleshooting device.
