The
circuit is designed to use very little current to prolong battery life
so that it can be left on permanently. A superbright’ red LED is used
because this provides a bright flash with a low current.
If you want to use 4.5V supply by connecting 3 Alkaline cells or any other source, change the resistor along with LED from 3.3k to 1k for a better flash.
Note that AA cells will last longer than a 9V PP3 battery
To flash two LEDs alternatively we have to increase the clock pulse speed to possibly fastest to have exact proper alternation.
Parts Required:
Circuit Diagram:
and their bread board arrangements
If you want to use 4.5V supply by connecting 3 Alkaline cells or any other source, change the resistor along with LED from 3.3k to 1k for a better flash.
Note that AA cells will last longer than a 9V PP3 battery
To flash two LEDs alternatively we have to increase the clock pulse speed to possibly fastest to have exact proper alternation.
Parts Required:
- 100k potentiometer
- 10k and 3.3k
- 10mF
- LED
- 555 Timer
- 9v Battery
There are three different modes to flash an LED using 555 Timer
and their bread board arrangements