This amplifier schematic/circuit has a very high gain, a pick-up microphone, and it can drive headphones or earphones. Can be run from only 1.5 Volts DC.
It has many practical uses. For example, the microphone can be used to pick up the sound of a TV that is set to a very low volume. The circuit will then amplify that sound and feed a loud version to the headphones. this makes it ideal for those cases where it's late at night and you need to be quite, but want to listen to your TV louder that your neighbors would normally like!! It might also be interesting to sit in a quite garden late and night and see what bug noises it picks up that you can't normally hear with just your regular ears.
The circuit uses less that 30 components in total, 4 of which are NPN transistors (3 x BC547, 1 x BC337). There is a log potentiometer used for volume/gain-control... so you can adjust the output volume depending on how loud or quite the sounds are.
Be careful not to blow your ears off!Parts List:
- Earphone Amplifier
- Earphone Amplifiers
- High Gain Amplifier Circuit
- Amplified Earphones