Some Past 431/531 Projects

• metal detector
• AM radio receiver
• IR (infra-red) remote control
• audio volume --> LED tree
• car/home alarms (light, IR interrupt; magnetic flux)
• instrument distortion box
• electronic keyboard
• touch control
• analog computations
• signal peak detector
• capacitance meter
• various instrumentation amplifiers
• resonant circuits with no inductors (op amps as inductance  replacements)
• bike speedometer
• auto-ranging voltmeter
• intermittent auto wiper controller
• communication by light
• communication by sound
• solar cell battery charger
• CD amplifier
• signal generator
• "clapper" (electronic response to an audio signal (hands clap))


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