The above shown circuit is LED as continuity tester. This circuit is used for checking continuity of cables, connectors and switches. When A and B terminals are shorted, the LED glows due to battery ...

could be used but I found no simple circuits. My first thought was just to connect a series current limiting resistor and LED to the cathode so that the LED would light when the reference ...

[Henryk] just sent us his latest episode of simple LED circuit puzzles. In front of the camera he solders one pin of each of the 3 LEDs to a different switch. He then puts the three assemblies in ...

Simple touch switch circuit with 4011 – source The circuit as you can see ... When the plate is touched the 555 timer is triggered and the output on pin 3 goes high turning on the LED and the buzzer ...

Here’s a simple project ... building the circuit, we took the project one step further by incorporating an Atmel ATtiny13 microcontroller. The code switches the LEDs on and off randomly for ...

We all carry supercomputers in our pockets and use dozens of electric gizmos every day but rarely stop to marvel at the magical act of flicking a switch ... circuit building. Master these simple ...