Most bipolar junction transistors and field-effect transistors (FETs) have three terminals. In the BJT symbol, the base lead is perpendicular to and lands at the midpoint of a short line segment representing the semiconductor substrate. The emitter has an arrowhead embedded in the lead, so the remaining lead has to be the collector. If the […]
FAQ
Difference between arc-fault circuit interrupters and ground-fault circuit interrupters
Arc-fault circuit interrupters (AFCIs) are sometimes confused with similar appearing ground-fault interrupters, GFCIs, which protect against electric shock. Rather than protecting against electric shock, AFCIs protect buildings and occupants from electrical fire. Internal electronics and operating principles of the two devices are entirely different. A GFCI protects the occupant from electric shock by detecting the […]
When a coronagraph comes in handy
You can think of a coronagraph as having the same effect as a total eclipse of the sun where only its outer edge is visible. It is a telescopic attachment designed to block out the direct light from a star. The early coronagraphs were intended to view the corona of the Sun. But a new […]
Working with fiber optic internet connections
Fiber internet service is often called the gold standard of residential internet connections thanks to the fact that a fiber internet connection can easily provide a 10x speedier connection than ordinary coax cable. Fiber-to-the-Home (FTTH) deployments by Verizon Fios and AT&T Fiber are capable of 4K video conferencing and ultra-fast file uploads. Such connections also […]
Five key considerations for spectrum analyzers
A bevy of specifications define how spectrum analyzers perform. But just a handful of qualities can be pivotal when it comes to selecting instrumentation. Contributed by Signal Hound As wireless technologies pervade our lives, more engineers find they must make RF measurements. In the past, RF testing required the use of expensive equipment handled only […]
Measuring picoseconds without breaking the bank
Modern analog/digital converters can help implement equivalent time sampling to provide picosecond timing resolution. Dave Guidry, Texas Instruments Inc. A picosecond is an astonishingly short period of time. Imagine a stopwatch with a trillion divisions between each tick of the second hand. While it sounds fantastical, this resolution of time measurement is indeed necessary for […]
Test and measurement connections in the world of 5G
Connectors and cabling can be as important as the test instruments used to check out systems operating in the 5G realm. John Muzzio, Times Microwave Systems Andrew Dinsdale, SV Microwave Unlike previous cellular technology generations that were focused on a specific frequency band, 5G deals with a much larger potential frequency range. For example, 4G […]
Raspberry Pi for DAQ
Though they are more closely associated with the maker space, Raspberry Pi boards can be effective at handling stringent industrial measurements. Steve Radecky, Measurement Computing Corp. Originally designed to be a cheap, almost disposable computer, Raspberry Pi was created to get kids interested in programming. Since its introduction in 2012, Raspberry Pi has become the […]
A scope-based technique for optimizing EMI input filters
A simple oscilloscope setup can size common-mode and differential-mode noise filtering components separately and more accurately. Marcus Sonst, Rohde & Schwarz Any switched-mode power supply (SMPS) needs an EMI (electromagnetic interference) input filter to avoid disturbing power lines. Input filters generally contain both common-mode and differential-mode filter elements, and the two are rarely optimized separately. […]
Sorting out PC-based instrumentation
It used to be the case that only a few kinds of relatively simple instruments were based on PCs. Now several categories of lab-grade instrumentation take the PC approach. Trevor Smith, Pico Technology The diversity of measurements that must be made by electronics engineers constitutes a huge challenge. The debugging and validation of components and […]