The high level of integration in today’s mmWave phone means traditional test methods no longer apply.
What is de-embedding and how do I perform it (part 2)?
When testing a device in a fixture, you can use transfer scattering parameters (T-parameters) to help remove the fixture’s contribution from your measurement result.
What is a Smith chart and why do I need one? (Part 2)
Take a journey around a Smith chart to find capacitance and inductance values in a matching network. Before computers became ubiquitous, the Smith chart simplified calculations involving the complex impedances found in RF/microwave circuits such as the one shown in Figure 1. That circuit includes a source with impedance Zs, transmission line with characteristic impedance […]
What is a Smith chart and why do I need one? (Part 1)
A Smith chart provides insight into RF/microwave designs. Even if you work primarily with low-speed analog and mixed-signal designs, you could benefit from familiarity with the Smith chart as wireless products proliferate and as high-speed-serial data signals exhibit microwave-like effects. When a signal’s wavelength (λ) approaches the lengths of the conductors carrying it, you can […]
Untangling accuracy, precision, and resolution, Part 2: Implications
Accuracy, precision, and resolution are key parameters, each with a distinct meaning and implication with respect to system design and confidence. Design, test, and measurement implications Low or moderate accuracy may seem a detriment, but that isn’t necessarily the case. If precision is good enough and there is a way to calibrate the readings, the […]
Untangling accuracy, precision, and resolution, Part 1: Basics
Accuracy, precision, and resolution are key parameters, each with a distinct meaning and implication with respect to system design and confidence. To the average person, terms such as accuracy and precision are somewhat interchangeable, and that’s fine. However, they have very specific and different meanings as well as design and test implications for scientists, engineers, […]
The perils of oscilloscope ground and power ground
Most electrical engineers probably are aware that connecting the ground connection for ordinary oscilloscope probes to the wrong part of an ac power line will invite a lot of trouble. Unfortunately the remedies sometimes employed to head off difficulties can cause their own woes. In a lab where I was once employed, the instrument carts […]
How to run video games on an oscilloscope
Spend enough time on YouTube and you’ll uncover numerous videos showing some kind of video game being played on an oscilloscope. The most popular game choices for these videos seem to be the old Doom and Quake games and Pong, the first real video game released in 1972. Perhaps the main reason for Doom’s popularity […]
The case for buying a used oscilloscope
Not all test labs need oscilloscopes sporting 1 GHz bandwidths and multi-million-point digital waveform recording. When the needs lean more toward the basic side, used scopes can sometimes fit the bill and do so economically. Here are a few points to consider before ponying up for a used scope. The go-to website for used equipment […]
Putting the spotlight on infrared sensor technology
William Herschel was a gifted musician and composer who by chance obtained a 10-foot long, 30-inch reflecting telescope from the estate of his deceased friend, a violinist. Due to damage in moving it, he had to rebuild the instrument. This drew him into telescope making and then astronomy. He also discovered infrared radiation by placing […]