This LED Flasher circuit is based on the 555 timer IC .The LED Flasher circuit diagram is very simple and require few external components . When the circuit is working the red LEDs will flash at a set frequency one by one like at the railway crossing indicator .
The circuit must be powered by a powers supply which can be provide an output voltage between 6 and 12 volts .
This electronic mosquito repellent electronic project is based on the 555 timer circuit. This electronic mosquito repellent circuit generate an ultrasonic sound with a high output frequency that allows spreading mosquitoes within a wide radius . The circuit is quite simple and require few external components . The oscillation frequency is given by the value of the R1, R2 and C1 components and can be modified changing the value of components or replacing the R2 fixed resistor with a variable resistor ( potentiometer ) .
This 555 timer circuit temperature monitoring system electronic project can be monitor temperature in up to four points. Using this 555 timer circuit temperature monitoring system electronic project can be choose if the alarm should be triggered when temperature is increased or decreased. This depends on the resistance R10. If you connect R10 between positive supply conductor and output 6 of IC2 then circuit sound the alarm when the temperature rise over the reference temperature. The reference temperature is set by potentiometer P1. Measured temperature is monitored by NTC resistance R9.