Tested bulbs are about six month old – considered expired. Spectrometer pics will be added ASAP.
I use this Kill A Watt meter to measure any device I have electricity questions about. I also use it to measure total system power usage and even to track cost over time. For the price, a Kill A Watt meter eliminates so many questions and has even given me some answers I didn't know the questions to yet!... Continue Reading →
This is a triangle calculator. Specifically, this is the open source triangle-calculator provided here: https://ostermiller.org/calc/triangle.html Since an LED emits light roughly in the shape of a cone, we can use triangle math to predict the amount of area an LED in a particular installation will light up. After the calculator has any three parts (not only... Continue Reading →
This is my Project STAR spectrometer. It was very inexpensive. I use it for examining the color of different lights inside and outside. (Don't look directly at the sun through this device – or anything else!) It works by taking in light via the small opening at the upper-right. The light bounces off the diffraction... Continue Reading →