This LED DC voltage indicator circuit is a voltmeter, rather than simply a battery tester. As such it may measure voltages as low as 3V. It utilizes venerable LM741 operational amplifiers applied as ...

If you’re working with 3.3V or 5V circuits, it’s easy for you to throw on a power or status LED here or there. [Tom Gralewicz] has found himself in a pickle, though, often working on projects with ...

The subject of the little LED indicator light on HTC Windows Phones has cropped up in a few of the WPCentral Forums discussions. Some are pleasantly surprised at seeing the little indicator, some are ...

If you are someone who tends to use a lot of power tools, the Ryobi ONE+ system is a pretty terrific investment. Through their standard 18V battery, you can power everything from drills to ratchets to ...