This circuit is designed to analyze the distortion of an audio signal. We found it in an article in the October 1988 Radio Electronics magazine that teaches how to use it.
Many reed switches can be wired in series to perform na efficient alarm as shoen in the figure....
This circuit to increase the sensitivity of instruments to 100 uA (or close to it) was found in...
November 2016 - Mouser Electronics is making available the new N Semiconductor STK984-190E power...