Does your audio amplifer have signal strength indicator? I've always envied the fancy amps with a graphical level meter signal on the LEDs, such that you can find a stereo system. This is your chance to design your own signal level meter, which you can connect to your audio amplifier and see how the signal.
The device is based on the chip LM3915. This monolithic integrated circuit from National Semiconductor is the driver for our device. At the 5 pin of the chip, we serve an analog voltage and the circuit operates 10 diodes in a logarithmic scale 3 dB / step.
