By David Herres Joseph Fourier (1768-1830), in his principal work, “On the Propagation of Heat in Solid Bodies” (1807), laid the groundwork for what is now known as the Fourier Transform. In years to follow it was modified by others to make it more generally applicable. Today the basic insight is central to our understanding […]
Flat-screen technology part one: Plasma
By David Herres A previous article discussed the cathode-ray tube, for a long time the only game in town for displaying waveforms. It provided a clear display and was capable of superb color rendition. But it has been almost totally supplanted in TVs, computer monitors, and oscilloscopes by newer flat-screen technologies. The two primary flat-screen […]
A simple human voice display on the oscilloscope
By David Herres For years, science-fiction movies — particularly those involving robots — have created ambience by placing an oscilloscope in the background, configured to display a trace of the human voice. You can do this easily, at minimal expense, and the resulting setup can be used to perform some interesting and instructive acoustic experiments. A loudspeaker as removed […]
Variable Frequency Drives: Viewing the DC Bus
By David Herres In the field of motion control it’s often necessary to vary the speed of an electric motor and even reverse its direction of rotation. When the application called for this kind of motor control, usual motor technology of choice was that of dc motors until the mid-twentieth century. It was easy to regulate […]
Mixed Domain Instrument Technology
By David Herres The Tektronix MDO4000 is what is known as an integrated oscilloscope. This means it combines the functions of specific electronic test equipment with that of the basic scope. These instruments are not simply packaged in the same box as if to conserve bench space. They are actually wired together in such a […]
Connecting the Tektronix MDO3104 Oscilloscope to a Remote Computer
By David Herres The Tektronix MDO3104 oscilloscope can be connected to a computer in several ways. If all you want to do is transmit the scope display to a computer, including any on-screen menus and information, insert a flash drive into the scope’s USB port, marked with its distinctive logo, on the front panel. With the […]
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 […]
When Oscilloscopes Went Digital
By David Herres The major players in oscilloscope development have been Tektronix Inc., Teledyne LeCroy Corp. and Agilent Technologies (originally Hewlett-Packard, now Keysight Technologies). These giants watch each other closely, each trying to outdo the others in delivering quality and innovation. It would be an understatement to say they are fiercely competitive, although the rivalry […]
Static Charge: Threat To CMOS And Other High-Impedance Devices
By David Herres In the world of semiconductors, a device said to have a high impedance really has a high-impedance input. A high-impedance device will typically have low output impedance. This is a satisfactory arrangement because any given stage will not overload the stage preceding it and will not be overloaded by the stage that follows […]
Triggering Enters the Picture
By David Herres The oscilloscope has its roots in nineteenth-century attempts at hand-drawn waveform imaging. The voltage or current of a spinning rotor could be viewed by means of a galvometer and the results plotted on graph paper. A later improvement on this crude process involved attaching a commutator, inspired by dc motor technology. Again […]
