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Audio Amplifiers: Microphone Amplifiers and Useful Amplifier...

Microphone Amplifier Electronic Circuits and Schematics

Photo: FM Transmitter kit with microphone (Wireless Mic) FM Transmitter kit with microphone (Wireless Mic)
FM microphone kit. Build an actual FM station that transmits over 100ft. Learn about microphones, RF oscillators, and how FM radio works.
Electret Condenser Microphone Amplifier
0 Comments - in Audio Amplifiers
Amplifier circuit for electret microphones (condenser microphones). Amplifier the audio signals picked up by the electret microphone, using 741 op-amp and a 2N2222 transistor.
Very Low Noise Balanced Microphone Preamplifier Circuit
1 Comment - in Audio Amplifiers
This microphone preamplifier circuit features high gain, super low-noise and balanced input.
Variable DC Power Supply (1-30 Volts, 5 Amps). LM338K Regulator
0 Comments - in DC Power Supplies
A very simple variable power supply with a DC output voltage adjustable from 1-3- Volts, with a maximum DC current of 5 Amps. Uses LM338 DC voltage regulator IC.
Photo: 3 Amp Variable DC Power Supply 3 Amp Variable DC Power Supply
Provides 3 amps current at 3-30 Volts DC. Reduces ripple voltage to almost non-existant.
LM317 1-25 Volts Variable DC 1.5 Amp Power Supply
3 Comments - in DC Power Supplies
An extremely simple and cheap DC power supply with variable voltage (1.2-25 Volts) control. The circuit uses an LM317 integrated voltage regulator Ic.
Photo: LM317 Variable Power Supply LM317 Variable Power Supply
A very basic power supply that can be adjusted over a range of about 1.5 to 35 volts DC. If you add a heat sink (included), you can run it as hot as 2 Amps output; otherwise about 60 mA @ 12 volts. This is a text book circuit using an LM317, which is a 3