Led bar-dot level meter

Posted on Jun 7, 2012

A simple level of power meter can be arranged to give a bar or dot display for a hi-fi system. Use green LEDs for 0 to 7; yellow for 8 and red for 9 to indicate peak power. The gain control is provided to enable calibration on the equipment with which the unit is used

Click here to download the full size of the above Circuit.

Because the unit draws some 200 mA, a power supply is advisable instead of running the unit from batteries.

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