I was using a test board I designed to measure component level radiated emissions. During the measurements I started to suspect that some of the emissions were coming from the test board. The only ...

Researchers report development of a low-cost carbon filter that can remove 90 percent of carbon dioxide gas from the smokestacks of electric power plants that burn coal and other fossil fuels. The new ...

Figure 1 shows how a Sallen-Key high pass filter (HPF), can be switched on/off using only one extra transistor and resistor. Figure 1 A Sallen-Key HPF filter topology that can be switched on/off using ...

Field tests in Nepal suggest that people who live in areas with arsenic-tainted aquifers may be able to purify their drinking water by passing it through a low-cost, low-tech filter with a simple ...