Electronics World articles Popular Electronics articles QST articles Radio & TV News articles Radio-Craft articles Radio-Electronics articles Short Wave Craft articles Wireless World articles Google Search of RF Cafe website Sitemap Electronics Equations Mathematics Equations Equations physics Manufacturers & distributors Engineer Jobs LinkedIn Crosswords Engineering Humor Kirt's Cogitations Engineering Event Calendar RF Engineering Quizzes USAF radar shop Notable Quotes App Notes Calculators Education Engineering Magazines Engineering magazine articles Engineering software Engineering smorgasbord RF Cafe Archives RF Cascade Workbook 2018 RF Stencils for Visio RF & EE Shapes for Word Advertising RF Cafe Homepage Sudoku puzzles Thank you for visiting RF Cafe!
Exodus Advanced Communications

- Welcome to the RF Cafe Website -
"...Difficulties in recognizing one's own incompetence lead to inflated self-assessments." -- Dunning-Kruger

Today in Science History

Tech Industry Headlines

Tech Industry Headlines - RF Cafe- Archive -

"Li-Fi" Link Exceeds 7 Gb/s Using Blue Micro LED

MARS Communications Exercise Involves Amateur Radio Community

• Northrop Grumman Awarded for Evolved Strategic SATCOM Program

170 Million Fixed Wireless Access Connections by 2025

• MIT Engineers Develop Flat Fish-Eye Lens

• Fab Emphasis Questioned as U.S. Chip Lobby Sounds Off

Smartphone Market Headed for Mid-Range Mediocrity

AMSAT-OSCAR-7 Approaching Return to Full Solar Illumination

U.S. Army Radios Show Anti-Jam Progress at Network Experiment

Microwaves - Receiving and Transmitting Antennas

Microwaves - Receiving and Transmitting Antennas, December 1949 Radio-Electronics - RF CafeThis is the eighth and final installment on a "Microwaves" series of articles in Radio-Electronics magazine by author C.W. Palmer. Each part is a stand-alone tutorial that does not rely on previous parts to be useful. Unlike most of the preceding articles that dealt in one way or another with waveguide, this final one concerns "receiving and transmitting antennas for microwave communication." It touches lightly on various types of antennas, field patterns, impedance matching, and applications. If you've been around for a while, you've likely seen it all before, but there are some nice photos of antennas designed and deployed by Bell Telephone Laboratories for their nationwide microwave telephone relay network. Bell Labs has done a lot of ground-breaking research in all aspects of communications technology...

Power Electronics with Microscopic Plumbing Saves Lots of Money

Power Electronics with Microscopic Plumbing Saves Lots of Money - RF Cafe"Designing semiconductor circuits hand-in-hand with microfluidic cooling systems could mean huge boosts in efficiency. The heat generated by today's densely-packed electronics is a costly resource drain. To keep systems at the right temperature for optimal computational performance, data center cooling in the U.S. consumes the as much energy and water as all the residents of the city of Philadelphia. Now, by integrating liquid cooling channels directly into semiconductor chips, researchers hope to reduce that drain at least in power electronics devices, making them smaller, cheaper and less energy-intensive. Traditionally, the electronics and the heat management system are designed and made separately..."

Quickly Assess Coax Cable Shielding Quality

Quickly Assess Coax Cable Shielding Quality - RF CafeKenneth Wyatt has a good article on the EDN website entitled, "Quickly Assess Relative Coax-Cable-Shielding Quality." It begins: "Testing most products for radiated emissions usually requires all I/O and power cables to be attached to the equipment under test (EUT) and spread out in accordance with the specific product standard. In many cases, we test engineers simply grab the nearest cables and hope for the best during the compliance test. Unfortunately, poor-quality cables can lead to emissions failures due to poor shielding or poor shield termination (via 'pigtails') to the connectors. In an earlier article, I related the issue of HDMI cable radiation due to shield pigtails. I also graphically demonstrate why cable shield pigtails lead to radiated emissions in the video. In addition to the shield pigtail issue, coax cables..."

WWV Offers Additional Services

WWV Offers Additional Services, April 1958 Radio-Electronics - RF CafeWWV is the oldest continuously-operating radio station in the U.S. since first going on the air from Washington, D.C. in May 1920. It moved around an area near D.C. for a few years before being relocated to its current location in Boulder, Colorado, in 1966. WWVB, another time standard transmitter, had already been established in Boulder a few years earlier. Sister station WWVH is located in Hawaii. The National Bureau of Standards (NBS) was renamed National Institute of Standards and Technology (NIST) in 1988, nearly a century after its inception in 1890. Having grown up not too far from Beltsville, Maryland, I remember driving by their main campus when the NBS sign was still on the lawn. The decision to change the name never did make sense, but then most of what government bureaucrats do perplex me...

Russian COVID-19 Vaccine Tests

Russian COVID-19 Vaccine Tests - RF CafeIn response to an article about the ongoing Wuhan Flu serum development programs, here is one of the cleverest online forum posts I've ever seen: "This might surprise many of you, but I volunteered for the vaccine trials for Covid-19. The vaccine is the one that was created in Russia. I received my first shot yesterday and I'm excited because it seems completely safe, with иo side effects whatsoeveя, and I feel sκ χoρoshό я чувствую себя немного странно и я думаю, что вытащил ослиные уши." Plug the Ruskie part into a translator.

Many Thanks to Aegis Power Systems for Their Continued Support!

Aegis Power Systems - RF CafeAegis Power Systems is a leading supplier of AC-DC and DC-DC power supplies for custom and special applications. Aegis has been designing and building highly reliable custom power supplies since 1995. They offer a complete line of switch mode power supplies and power converters for a variety of markets including defense, industrial, aircraft, VME, and telecom. Supports military, aircraft, EV, telecom, and embedded computing applications. Design and manufacture of custom power supply solutions to meet each customer's exacting specifications. Please visit Aegis Power Systems today.

Cakes Baked in 90 Seconds - Early Microwave Oven

Cakes Baked in 90 Seconds - Early Microwave Oven, November 1951 Radio & Television News - RF CafeLittle known to most people (including moi until recently), DeForest Training School was started by DeVry University's founder Herman A. DeVry. DeVry and DeForest were DeGood DeFriends, leading DeVry to name his electronics school after DeForest. It was re-named DeVry Technical Institute in 1953. Research at DeForest Training School produced one of the first RF / microwave food baking "ovens." The prototype reported in this 1951 Radio & Television News magazine article was not at all like modern microwave ovens. There was no enclosure into which baking bowls, pans, and dishes can be inserted. Rather, electrodes were arranged at the perimeters of the special pan that in this demonstration contained cake batter. It was adapted from a process originally developed for RF induction heating of industrial materials...

Many Thanks to Electro-Photonics for Their Continued Support

Electro-PhotonicsElectro-Photonics is a global supplier of RF & Microwave components. Their products include SMT hybrid and directional couplers, wire bondable passive components, mounting tabs, filters, transmission lines, and very useful test boards for evaluating components (spiral inductors, single-layer capacitors). The Electro-Photonics team can support your small R&D design requirements with RF & Microwave test fixtures and save you valuable design and characterization time. Please take a moment to visit Electro-Photonics' website and see how your project might benefit. 

Radiation-Tolerant FPGAs Solve Spacecraft Design Challenges

Radiation-Tolerant FPGAs Solve Spacecraft Design Challenges - RF Cafe"Satellite and spacecraft system designers have a few different options when selecting field programmable gate arrays (FPGA) semiconductors. One FPGA option is commercial off-the-shelf (COTS) components that reduce component unit cost and lead time, but they are generally not reliable enough, must be up-screened (which increases cost and engineering resources), and require soft and hard Triple Modular Redundancy (TMR) to mitigate radiation effects in space. In missions where failure is not an option, designers typically choose higher-cost FPGAs that are radiation-hardened by design (RHBD). These are already screened and qualified to Qualified Manufacturers List (QML) Class Q and V standards..."

Hobnobbing with Harbaugh: Biocells Revisited

Hobnobbing with Harbaugh: Biocells Revisited, September 1964 Popular Electronics - RF Cafe"Hobnobbing with Harbaugh" was a regular comic feature in Popular Electronics magazine in the 1960s. Creator Dave Harbaugh chose topics ranging from husband-wife relationships where the husband is a technophile of some sort and the wife either purposely or unknowingly challenges his efforts to participate in his hobby, to contemporary (at the time) subjects such as this month's treatment of biocells. Like solid state electronics back in the day, bioengineering was a mysterious field few understood. It received a great deal of attention by comedians and sci-fi film makers who got a kick out of scaring people over the possibility of an alien contamination (a la "The Andromeda Strain") or some secret government laboratory brewing up a deadly contagion...

Anatech Microwave September 2020 Product Update

Anatech Microwave September 2020 Product Update - RF CafeAnatech Electronics offers the industry's largest portfolio of high-performance standard and customized RF and microwave filters and filter-related products for military, commercial, aerospace and defense, and industrial applications up to 40 GHz. One each new cavity-type duplexer and triplexer have been introduced. The AD1542-1643D296 is an Inmarsat duplexer with 1524-1560 MHz and 1626.5-1660.5 MHz passbands, and the AD1800-2072-2250TR293 is a triplexer with 2025-2120 MHz, 2200-2230 MHz, and 1750-1850 MHz. Passband insertion loos is >15 dB on all, and insertion loss is <1 dB. Custom RF power directional coupler designs can be designed and produced...

Free Webinar: Build Your Own Radar at Home

Professor David Ricketts, NCSU - RF CafeOn September 29th beginning at Noon EDT, Cadence | AWR will be presenting a free webinar entitled NCSU Rabbit Radar - Design, Simulate & Build Your Own Radar at Home. "In this webinar, Dr. Ricketts describes how to design, simulate, and build a 2.4GHz frequency modulated continuous wave (FMCW) radar at home or in a lab. The webinar begins with a short theory session followed by an explanation of the key components of an FMCW radar, which include a mixer, power amplifier, coupler, low noise amplifier, and filters. The components will use transmission line structures that attendees will design...

Please Visit NorthEast RF's Website in Appreciation of Their Support

NorthEast RF - RF CafeNorthEast RF's comprehensive antenna testing services include linear | circular polarized antenna measurements and OTA cellular device pre-compliance. Up to 18" diameter and <10 kg weight. Antennas can be rapidly evaluated and optimized using our fast near field spherical system. Test results supplied in data file with pattern viewer software. A picture of the test configuration is included to help aligned axis. Our selection of human head and hand phantoms are ideal for verification of body worn devices. Turnaround time is usually 3-days.

Crystal Diodes in Modern Electronics

Crystal Diodes in Modern Electronics, November 1951 Radio & Television News - RF CafeUse of the word "modern" in titles of books and magazine articles has always bothered me because of how quickly the referenced topic becomes obsolete. It is only "modern" for a relatively short period of time. In 1951 when this article appeared in Radio & Television News magazine, germanium was the dominant semiconductor in use for diodes and transistors. They could be used in small signal circuits of up to about 500 MHz. That meant they could easily replace vacuum tubes in AM and FM radios, and at least the IF and baseband sections of TVs. You might think that would have represented a big component cost savings, but semiconductors were much more expensive than vacuum tubes at the time. Still, the power savings, size reduction, and higher reliability made the circuit changes worthwhile...

DARPA's Ultra-Linear High-Speed GaN Advances to Next Phase

DARPA's Ultra-Linear High-Speed GaN Advances to Next Phase - RF Cafe"A team of researchers at HRL laboratories, led by Principal Investigator Dr. Jeong-Sun Moon, is developing the next generation of Gallium Nitride (GaN) transistors that will have a dramatic effect on electronic components that amplify electromagnetic signals for communications, radar, and 5G wireless networks. The ultra-linear monolithic microwave integrated circuit (MMIC) amplifiers that utilize these high-speed GaN transistors can see greatly improved linearity, noise reduction, and reduced power consumption. Moon's team has successfully met and exceeded the performance metrics defined by the Dynamic Range-enhanced Electronics and Materials (DREaM) program, a DARPA effort to improve dynamic range in millimeter-wave..."

IPP Needs an RF/Microwave Design Engineer

Innovative Power Products Needs an RF/Microwave Design Engineer - RF CafeInnovative Power Products (IPP), a company with over 35 years of experience designing and manufacturing RF and microwave passive components, wants to immediately fill an opening for an RF/Microwave Design Engineer. The position requires demonstrated success in the design and test of wide band, high power RF and microwave passive components. Candidate to be familiar with linear and full-wave EM simulators. Responsibilities include design, simulation, engineering document release, and prototype test of new products. He/she will communicate with customers, travel as required to visit customers or vendors, collaborate with Design and Drafting to satisfy customer requirements. Train and support technicians on S-parameters, test procedures, troubleshooting, and documentation of product...

Planes Can Land in Fog! Thanks to Short Waves

Planes Can Land in Fog! Thanks to Short Waves, December 1931/January 1932 Short Wave Craft - RF CafeThe Instrument Landing Systems (ILS) has been around since the early 1930s, as made apparent by this article in Short Wave Craft magazine. Frequencies, circuits, and infrastructure equipment have evolved over the years, but fundamentally, landing an aircraft (airplane, helicopter, dirigible) under 'blind' flying conditions has not changed. Two precision beams - one in elevation and one in azimuth - broadcast by ground-based installations are detected by airborne receivers and relative positions are displayed for the pilot's use in navigation. ILS does not help the pilot fly the aircraft; it only leads him to the runway threshold. In the past couple decades, space-based Global Positioning System (GPS) equipment has increasingly been used to replace ground-based microwave systems...

Teledyne e2v HiRel Intros 25 GHz Frequency Doubler

Teledyne e2v HiRel Expands RF Line with New 25 GHz Frequency Doubler - RF CafeTeledyne e2v HiRel, part of the Teledyne Defense Electronics Group, today announced the latest addition to its rapidly expanding line of RF solutions, a new RF MMIC Frequency Doubler. Launching Teledyne e2v HiRel's new Frequency Multiplier product line, this Active Doubler, TDFM001000, is designed for high reliability signal chain applications in Space. It is particularly well-suited specifically for satellite transponders, transmit/receive modules, microwave-based communications, millimeter-wave point-to-point radio, and related processes. The TDFM001000 is a 7.5-25.0 / 15.0-50.0 GHz single ended input (no external balun required) GaAs MMIC doubler...

KiloDrone: Intense Sound of 1,000 Analog Oscillators

KiloDrone Intense Sound of 1,000 Analog Oscillators - RF CafeThe October issue of IEEE's Spectrum magazine ran an article entitled, "Let a Thousand Analog Oscillators Sing." It reports on Sam Battle's "KiloDrone" DIY project consisting of 1,000 analog reverse-avalanche oscillators, each built with a transistor, capacitor, and resistor. A singe opamp isolates and amplifies the output of each unit. In his video Mr. Battle explains the project, runs through the tune-up procedure, and exhibits the final result. According to the story, only 1.2 A is used from a 12 V DC supply for the entire setup. There are 10 independently tuned oscillators on each rack-mountable panel. A printed PCB panel (not including components) can be purchased for $52. Bob Pease would have loved this guy whose motivation is summarized thusly: "I like the tangibility of analog. I hate working on computers. I just can't stand looking at screens. I like standing up and moving around and making things in a physical world."

Many Thanks to ISOTEC for Continued Support!

ISOTEC Corporation - RF CafeSince 1996, ISOTEC has designed, developed and manufactured an extensive line of RF/microwave connectors, between-series adapters, RF components and filters for wireless service providers including non-magnetic connectors for quantum computing and MRI equipments etc. ISOTEC's product line includes low-PIM RF connectors components such as power dividers and directional couplers. Off-the-shelf and customized products up to 40 GHz and our low-PIM products can meet -160 dBc with 2 tones and 20 W test. Quick prototyping, advanced in-house testing and high-performance. Designs that are cost effective practical and repeatable.

Anatech Electronics (RF Filters) - RF Cafe ConductRF Phased Matched RF Cables - RF Cafe
NorthEast RF Antenna Testing Services
About RF Cafe
Kirt Blattenberger - RF Cafe Webmaster
Copyright: 1996 - 2024
    Kirt Blattenberger,

RF Cafe began life in 1996 as "RF Tools" in an AOL screen name web space totaling 2 MB. Its primary purpose was to provide me with ready access to commonly needed formulas and reference material while performing my work as an RF system and circuit design engineer. The World Wide Web (Internet) was largely an unknown entity at the time and bandwidth was a scarce commodity. Dial-up modems blazed along at 14.4 kbps while typing up your telephone line, and a nice lady's voice announced "You've Got Mail" when a new message arrived...

All trademarks, copyrights, patents, and other rights of ownership to images and text used on the RF Cafe website are hereby acknowledged.

My Hobby Website:  AirplanesAndRockets.com


Please Support RF Cafe by purchasing my  ridiculously low−priced products, all of which I created.

These Are Available for Free