Unlike the analog D'Arsonval meter, a “thermometer scale” is an analog indicator with no moving parts. (If you don't know about this ubiquitous and historical analog meter movement, click here.) It is ...

An LED is commonly used as a "power on" indicator for many electronic devices. For the LED to produce discernible visible light in daylight, the forward-bias current needs to be in the moderate range ...

You’ve got an apparently simple design requirement on your latest AC-line powered project: provide a distinctly illuminated indicator to show that the unit is plugged into the line and that power is ...