The above circuit uses a 555 timer U1 in mono stable mode. If once push button is pressed, it drives pin2 of timer momentarily to ground that triggers the 555 to deliver a high output at pin 3 to ...
“You could’ve done that with a 555 timer.” But what if all you have on hand is an ESP8266? [TechColab] needed to control a solenoid valve with a short pulse via a solid-state relay (SSR) but found ...