The polarity markings on LEDs (Light Emitting Diodes) seem to be a common cause of confusion. The polarity may be indicated by a flat section on one side of the body or by one lead being shorter than ...

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 are experiencing issues with your ASUS PC, you can troubleshoot the problem by viewing the status of the Q-LED indicators. This article shows how to troubleshoot ASUS motherboard with Q-LED ...