Martin Lorton] has a vintage Harmon 4200B selective voltmeter that needed repair. He picked it up on eBay, and he knew it wasn’t working, but it was in good condition, especially for the ...

A standard electret microphone can detect sub-audio "sounds" when some simple equalization circuitry is added.

Analog-to-digital converters are the heart of most test equipment, setting the stage for the digital processing of analog ...

Eldo is one of the most widely used circuit simulators with over 20,000 licenses worldwide. Eldo is the core engine of the Mentor Graphics analog and mixed-signal product line, from a comprehensive ...