Part 1 of this article discussed the concept and basic implementation of the end of train (EOT) device. This part explores the EOT and its larger “ecosystem” in more detail. First, a bit of history While the first caboose replacement was a simple flashing rear-end device (FRED), first used by the Florida East Coast Railroad […]
Sorry, but it’s “Goodbye, Caboose” – EoT devices have made you obsolete, Part 1
The venerable-freight train caboose of history has been made obsolete over the past few decades by sophisticated, rugged, electronic end-of-train (EOT) devices which do much more, much better, and much cheaper. Ah, the caboose (Figure 1): it’s a railroad car which combines practicality, utility, legend, imagery, history, nostalgia, romance, dreams, myths, and so much more. […]
RF/Microwave bandpass filter implementations, Part 3: microstrip, coaxial, and helical filters
Part 2 looked at two types of RF/microwave filters, but there are many more, including ceramic coaxial filters and helical filters. They are discussed in this part. Microstrip filters Microstrip filters are built as a carefully defined pattern on a PC board. There is almost no limit to the filter designs which can be built […]
RF/Microwave bandpass filter implementations, Part 2: Cavity and comb filters
The well-known and extensively analyzed lumped-element bandpass filter is generally not suitable for the RF/microwave region, but there are many distributed-element, energy-based alternatives. Part 1 of this article established the context for these RF/microwave filters, which operate in the spectrum from several hundred MHz and higher, and increasingly cannot use discrete lumped-circuit elements (RLCs). Instead, […]
RF/Microwave bandpass filter implementations, Part 1: Distributed filters
The well-known and extensively analyzed lumped-element bandpass filter is generally not suitable for the RF/microwave region, but there are many distributed-element, energy-based alternatives. Just say the word “filters,” and for many engineers, the mention of this topic stirs a mix of feelings ranging from fear to relief. Why fear? Because filters as a topic in […]
Advancements create easy-to-use sensors
By Bill Schweber for Mouser Electronics Significant advances have been made in delivering high-performance, low-cost, easy-to-use sensors for a diverse range of physical phenomena, with progress often based on micro-electromechanical systems (MEMS) technology. There’s always been a widespread need for electronic sensors that can handle the diverse range of physical phenomena such as light, pressure, […]
Lasers, optics, electronics and more yield terahertz sources, Part 4 – Laughing gas
The terahertz part of the electromagnetic spectrum between millimeter waves and optical range remains a largely untapped, difficult-to-use resource; researchers are investigating different techniques for efficiently generating terahertz waves to promote the use of this part of the spectrum. Approach #3: Laughing Gas A team at MIT in close collaboration with one at nearby […]
Lasers, optics, electronics and more yield terahertz sources, Part 3 – Infrared lasers and plasma
The terahertz part of the electromagnetic spectrum between millimeter waves and optical range remains a largely untapped, difficult-to-use resource; researchers are investigating different techniques for efficiently generating terahertz waves to promote use of this part of the spectrum. Approach #2: Infrared Lasers and Plasma A research group based at TU Wein (Vienna University of Technology), […]
Lasers, optics, electronics and more yield terahertz sources, Part 2 – Lasers and acoustics
The terahertz part of the electromagnetic spectrum between millimeter waves and optical range remains a largely untapped, difficult-to-use resource; researchers are investigating different techniques for efficiently generating terahertz waves to promote the use of this part of the spectrum. Approach #1: Lasers and Acoustic Modulation A recent project and paper by a collaborative team from […]
Lasers, optics, electronics and more yield terahertz sources, Part 1 – Context
The terahertz part of the electromagnetic spectrum between millimeter waves and optical range remains a largely untapped, difficult-to-use resource; researchers are investigating different techniques for efficiently generating terahertz waves to promote the use of this part of the spectrum. Electromagnetic energy in the terahertz (THz) region of the spectrum, nominally 300 GHz/0.3 THz to 10 […]