Welcome to TechCrunch’s 2021 Holiday Gift Guide! Need help with gift ideas? We’ve got lots of them. We’re just starting to roll out this year’s gift guides, so check back from now until the end of ...

Gift-giving for engineers, kids, Makers, electronics hobbyists, or geeks becomes effortless with our suggestions, which include possible places to buy. Stocking stuffers can be had for as little as ...

a 12 V battery; an LED diode; a 470 Ohm resistor, which works as protection and limitation for the LED diode; a 12 V buzzer. It emits an acoustic sound if it is electrically powered. As can be seen ...

In a previous article, we explored the behavior of an LED diode as a small light source. We have seen how important a protection resistor is to light up this component. In this article, we will ...