This is an audio power meter simple with this circuit, dual LED starts to light green around 0.1 watts into 8 ohms (0.2 watt into 4 ohms). Naturally, this depends on the specific type of LED is used. Despite being a simple equipment he is impressively bench since with a load resistor connected to output of speakers is possible to measure the sound level up, or just check its output.
Audio Power Meter Circuit Diagram
Sourced By: circuitsproject
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