Did you know that you can use Arduino to turn on an LED when you press a button? Well, it is true, you can do this! Leaving the joke aside, let me show how you can achieve this. You will need the ...

PIC, AVR, and Arduino are ubiquitous ... to use a momentary tactile switch to turn something on and off. Instead of going with a microcontroller he built the circuit around a 555 timer.

[Ed] was tasked with adding push-button degaussing ... to use an SSR to switch the coil, and after making lots of transistor-based designs on paper, grabbed a nearby Arduino.

The code (Arduino sketch) allows push button increment of the counter from 0 to 9. The whole circuit can be powered from a standard ... In case of any doubt refer this table. Push Switch (S1) input ...