9 Sound Cards on the Rack
The quality of A/D and D/A converters makes it quite tempting to use a sound card for audio equipment measurements, especially as it fits quite nicely in the Windows environment. However, it takes more than good converters to make a good instrument, as we all know. Our test shows how well a number of sound cards score with real signals.
With the SAPS-400 we offer a powerful, adjustable symmetrical supply that's ideal for lightweight audio power amplifiers and happily sits in less than a quarter of the space taken by a comparable supply of conventional design.
This low-cost project allows you to connect from 1 up to 128 digital thermometers like the Dallas DS18B20 directly on a single two-wire cable. All temperature values are recorded on your PC through a USB port without memory space limitation. Using the software manager developed for the project you can monitor the temperature in real time and set an alarm threshold value for each individual thermometer.
2-Pound RLC Meter
Is it possible to make an RLC meter for less than two pounds? In this article the authors answer this question with a resounding "yes" in the form of a simple and compact circuit that will enable you to make RLC measurements rapidly, accurately, and, above all, cheaply.
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