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

The ALP280e and ALP280e-MIC are French manufacturer Digigram’s latest additions to a sound card line that launched in 2022.

Lelantos Inc. (New York, NY) - $75,000. Lelantos is a developer of miniaturized semiconductor gas sensors based in New York, ...

With the MBTA’s analog system, one failure among thousands of individual points connecting the electrical equipment can ruin ...