The Â·circuit includes a peak detector that irrunediately drives the readout to any new higher signal level and slowly lowers it after the signal drops to zero. The readout is a moving dot or expanding bar display. The circuit can be expanded for a longer bar readout. Tapping five or more LED peakmeters into a frequency equalizer or series of audio filters should give a unique result.
The bottom LED remains on with no signal at tbe input, thus providing a pilot light for the unit.