As every test engineer planning out their Test Program Sets has probably heard at some point, keeping up with calibration is crucial. But how do you know when to get your test equipment hardware calibrated, and why exactly is it so important? Not only is it mandated by government agencies, required by quality regulations, and monitored by international standards groups- it directly impacts the efficacy of your equipment over time. While regular calibration may seem like a tedious extra step, it is clear that the benefits are well worth it. Here at Apex Waves, our stock of NI parts is fully calibrated, so each part is ready to ship to you right when you need it- at the highest quality condition available on the market.
The specific characteristics of a signal can be measured by a variety of instruments. For example, a counter can measure a signal’s frequency or its period, and an ac voltmeter can measure the RMS value of the signal. Although these instruments are very useful and can be more accurate than the oscilloscope, their application is mainly limited to the measurement of one parameter of the signal. With an oscilloscope, one can visualize the signal of interest and also observe whether the signal contains properties that would not be made apparent by most other instruments (for example, whether the signal is superimposed on a de level, or whether there are noise or relative hf oscillations present with the signal at the test point). Thus the oscilloscope is a more valuable instrument because it gives an exact visual representation of the signal waveform.
Whether you install, operate, repair, or design electrical equipment, you must know how to measure and test many types of electrical characteristics. The most imperative of these are electrical current, voltage, and resistance. Additionally, there are various applications that also require the testing and measuring of power, power factor, frequency, impedance, and sensitivity, as well as special component characteristics, such as capacitance and inductance.
Sampling is the taking of a specimen, or a part, to illustrate the whole. For example, when a ship’s cargo of sugar must be checked for the amount (%) of water in the sugar, specimens of the sugar are taken from various places in the ship. The more specimens are taken, the more information is available about the quality of the cargo overall. It is evident that to be 100% sure about the condition of the cargo, all the sugar present in the ship would have to be checked; however, this is not possible.
Tektronix is a globally-recognized source of equipment for engineers, scientists, and technicians. Known for their innovative measurement technology, they have created tools like oscilloscopes that have aided in the advancement of fields like health, communication, and space science. There are new discoveries in science and technology virtually every day, so it’s imminent that what used to be some of the company’s greatest products are replaced with newer, upgraded models. But just because they’ve been replaced doesn’t mean they’re forgotten. Here are some of the best discontinued oscilloscopes from Tektronix.
To prevent interference on receiving apparatus, for example, audio and TV receivers or computer systems, signals generated in the line supply and the radiated electromagnetic field of radio frequency from electrical equipment may not exceed certain limits. For this, the IEC makes recommendations. A special committee of the IEC, the CISPR (International Special Committee on Radio Interference), has published several definitions concerning measuring sets and measurement procedures for the various types of interference-producing equipment.
The 15-MHz portable dual-trace oscilloscope Philips PM 3226 is a compact, lightweight instrument featuring simplicity of operation, for a wide range of use in servicing, research, and educational applications. Other features include provision for chopped or alternate display of Y signals, automatic triggering, mains triggering, and triggering on the line and frame sync pulses of a television signal. The cathode-ray tube displays a useful screen area calibrated into 8 x 10 divisions by an external graticule.
Very often hum is present on the signals under test. This can be easily determined from the screen because the hum is related to the line frequency. If a signal shows a kind of unexpected amplitude modulation, switching back the time-base setting to about 5 to 10 or 20 ms/div, and switching over the trigger source selector to MAINS (or LINE), will generally result in a stable picture in the event of hum.
While measuring complex waveforms in digital techniques, mistakes can be made very easily. In this section, examples of this are presented. Some of them are explained in detail, to gain knowledge about the possible reasons for false triggering, which leads to wrong timing displays on the screen.
In digital techniques, it can happen that two pulses appear in a timerelated sequence, but that the second pulse appears a little later, with a delay, with respect to the first one.