Free simple 555 timer circuits electronics projects with explanation and diagrams. Huge collection of electronics projects based on the 555 timer circuit or equivalent integrated circuits.
An very simple smoke detector circuit can be constructed using a 555 timer circuit and a photo interrupter . The photo interrupter module is used as the smoke detector, while timer 555 is wired in astable configuration as an AF oscillator for sounding alarm via a loudspeaker.
A very simple electronic key code lock circuit that require few external components can be constructed using this schematic diagram . This electronic key code lock circuit is based on a common 555 timer circuit and some other common components .
