This circuit is a simple digital volume control. The integrated circuit DS1669 is the one that increases or reduces the volume by means of two push buttons.
The LM386 is a power amplifier designed for use in low voltage consummer applications.
Five-point graphic equalizer BA3812L rn
The circuit is based on a 16F873A microcontroller PIC.
This circuit can be set up in any computer you want to switch on/off by bringing your finger or any object close to the sensor.
This circuit is made up of two integrated circuits: an analogue to digital converter (CA3162), and a decoder of seven segments (CA3161).
This circuit allows us to connect a 128x64 display with the PC parallel port.
With this circuit we recompense the human ear deficiency to perceive less sharp and less deep tones of those that a melody really has at low volume.
This amplifier is especially suited for use in 3V micro cassette recorder, mini cassette recorder, headphone stereo applications.
Based on the Countdown with LCD 2x16, we have made this variant of the countdown. The countdown circuit, or the backwards counting we shall describe, shows the visualisation of the backwards counting on four 7 segment displays.
This simple circuit is made in order to regulate the luminous intensity of one or several incandescent lamps, or, as we know them, light bulbs, with a potentiometer.
That simple power supply is based on the usual 12 volts 7812 voltage regulator.