By David Herres Unlike residential wiring, the electrical harness in an industrial or large commercial setting usually carries three-phase power. To many homeowners and beginning technologists, three-phase circuits are a big mystery only because they are unfamiliar. Actually they are simple, conceptually and in terms of the labor involved when working with three-phase equipment. Three-phase conductors are […]
FAQ
Basics of CMOS
By David Herres Complementary metal-oxide semiconductor (CMOS) is a highly successful strategy for combining complementary and symmetrical pairs of p-type and n-type MOSFETs to create logic functions. A CMOS transistor pair is typically a building block for integrated circuits. Among its many applications are image sensors in digital cameras, data converters and transceivers. In a […]
Sine wave basics and applications in oscilloscopes
By David Herres Oscilloscopes typically display the amplitude of a signal on the Y axis as a function of time on the X axis. The resulting display can take the form of a straight horizontal line if it is a dc voltage, an irregular non-recurring and intermittent pattern for complex signals such as the human voice, […]
How much bandwidth?
The cost of an oscilloscope depends primarily on its bandwidth and, to a lesser degree, on added features such as an internal arbitrary function generator (AFG) and other options. If the price of the instrument is acceptable, the rational choice would be to go for the best device immediately. But in the real world most […]
Understanding the basics: What is characteristic impedance?
We speak of 50- or 75-Ω coaxial cable. The novice wonders if these numbers apply to a given length, say 100 ft. Could you connect an ohmmeter to one end of the cable and expect to get that reading with or without the conductors shunted at the far end? The answer is absolutely not. The characteristic impedance […]
