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"Maybe your purpose on this planet isn't on this planet." -- U.S. Space Command

Today in Science History

Tech Industry Headlines

Tech Industry Headlines - RF Cafe- Archive -

• FCC Moving on Unique 2.5 GHz Auction, License Areas

• DARPA Opens Door to Producing "Unimaginable" Designs for DoD

• Highly Efficient Supercapacitor Could Rival Batteries

• T-Mobile Seeks Access to More 2.5 GHz Spectrum

• Secrets of Tempest's Ground-breaking Radar Revealed

• FCC Reminds Hams Not to Use Radios in Crimes at Inauguration (amazingly audacious)

• CBRS Alliance Broadens Spectrum-Sharing Scope

• 2021 5G and Wireless Predictions Affected by Wuhan Virus

• U.S. Labor Market Losing Speed as Wuhan Flu Spirals out of Control

Electric Space Ships

Electric Space Ships, January 1951 Radio-Electronics - RF CafeWe've all heard of a Van de Graaff (Robert J.) electrostatic generator, but have you heard of a Wommelsdorf (Heinrich) generator (aka influence machine)? I hadn't prior to reading this article entitled "Electric Space Ships" from a 1951 issue of Radio-Electronics magazine. It took careful reading to get my head around the propulsion scheme detailed by Professor Hermann. At first I thought he was describing electric propulsion, but in fact his machine uses electrical energy generated from the sun to accelerate some form of liquid propellant via static electric charges. Therefore, this is not a system capable of indefinitely sustaining itself and its payload (which includes human inhabitants). In fact, the good professor proposes a geostationary refueling station above the Earth...

Bound-Charge Engineering: Developing Nanowire Transistors

Bound-Charge Engineering: A New Strategy to Develop Nanowire Transistors - RF Cafe"In recent years, physicists and electronic engineers have been trying to identify materials that could be used to fabricate new types of electronic devices. 1-D and 2-D materials have been found to have particularly advantageous characteristics, particularly for the development of new generations of nanoelectronics (electronic components at the nano scale). Such 1-D and 2-D materials, such as graphene, monolayer molybdenum disulfide, silicon nanowires and silicon nanosheets, could also play a crucial role within the semiconductor industry, as they could help to develop increasingly small transistors. Despite their well-documented advantages, emerging low-dimensional materials can have a relatively small amount of so-called free charges compared to 3-D materials. In the context of electronic components, a free charge is an electron or hole..."

Lead RF Design Engineer Needed by Copper Mountain Technologies

Lead RF Design Engineer Needed by Copper Mountain Technologies - RF CafeCopper Mountain Technologies (CMT) is seeking a Lead RF Design Engineer to develop new VNAs for customers all over the world. Our USB VNAs are next generation analyzers designed to meet the needs of 21st Century engineers. Our VNAs include an RF measurement module and a processing module, a software application which runs on a Windows or Linux PC, connecting to the measurement hardware via USB interface. The Lead RF Design Engineer will lead a team of engineers developing new USB VNAs, meeting new customer requirements, and evolving current product line. This individual will work closely with product management, manufacturing and other engineering teams to ensure delivery of quality solutions to customers. Take this opportunity to join a great company. Preferred location for this position...

Censorship vs. Radio Progress

Censorship vs. Radio Progress, December 1942 Radio-Craft - RF CafeHaving spent a lot of my career working for defense electronics companies in classified programs, I am somewhat torn between sympathizing with Hugo Gernsback from his perspective as editor of Radio-Craft and what I know is a valid reason for guarding certain technological information for the sake of military advantage. It is often the case that people who have had no exposure to the 'black' side of industry cannot appreciate the need for it. Their argument postulates that suppressing knowledge does more harm than good because an opportunity for more people to gain from breakthroughs will result in more rapid advancement in technology. While that is true, the downside is that the enemy rarely feels obliged to reciprocate in the same manner, and will exploit your generosity...

Skyworks & ASUS Launch World's 1st Ultra−Fast Wi−Fi 6E Router

Skyworks Partners with ASUS to Launch World's First Ultra-Fast Wi-Fi 6E Extended Band Router - RF CafeSkyworks Solutions, an innovator of high-performance analog semiconductors connecting people, places and things, today announced that its high-performance Wi-Fi 6E front-end modules are featured on the world's first ultra-fast Wi-Fi 6E gaming router from ASUS. Utilizing the FCC's newly allocated 6~7 GHz extended band to double the capacity of traditional Wi-Fi, the Wi-Fi 6E standard enables faster connectivity and supports an increased number of connected users meeting the unprecedented demand for increased video conferencing, online gaming, streaming TV, AR/VR, home security cameras and online exercise apps. An established leader in the networking market, ASUS is the first to deliver the increased and wider bandwidth 160 MHz channels of Wi-Fi 6E with its ROG Rapture GT-AXE11000 gaming router...

Please Thank Centric RF for Continued Support!

Centric RF microwave components - RF CafeCentric RF is a company offering from stock various RF and Microwave coaxial components, including attenuators, adapters, cable assemblies, terminations, power dividers, and more. We believe in offering high performance parts from stock at a reasonable cost. Frequency ranges of 0-110 GHz at power levels from 0.5-500 watts are available off the shelf. Order today, ship today! Centric RF is currently looking for vendors to partner with them. Please visit Centric RF today.

National Union Radio Corporation Tubes

National Union Radio Corporation, March 1944 Radio-Craft - RF Cafe"Necessity is the mother of invention," is an oft-heard maxim that is validated continually. Such was the case, as pointed out here in this National Union Radio Corporation ad which appeared in a 1944 issue of Radio-Craft magazine. The development of many new metal alloys was required in order to obtain the kind of performance and reliability needed in ever-evolving electronics products. Already available metals for filaments, coils, grid wires, getters, electron guns and many other constituents of vacuum tubes that are subject to high temperatures (many hundreds of degrees) and mechanical conditions (unequal coefficients of expansion, for example, which can cause stress fractures), were not sufficient for the task. Metallurgists had their work cut out for them...

Empower RF Systems Intros Rugged L-Band Satcom Uplink SSPA

Empower RF Systems Intros Rugged L-Band SSPA for Satcom Uplink - RF CafeEmpower RF Systems' tactical up-armored Model 2224 is a compact SSPA operating from 1 to 2 GHz, delivering 150 Watts CW output. The amplifier includes a fast Tx/Rx switch and is designed for rugged outdoor and tactical deployment of data com links. The all-weather heavy duty NEMA 4 enclosure houses a complete amplifier system using our Next Generation architecture so all the local and remote control, monitoring, protections and user remote GUI are identical to our COTS rack systems. The 2224 comes complete with internal directional coupler, internal forward and reverse power sampling and an easy to use remote web GUI. In depth health monitoring can be viewed remotely and pushed out via the Ethernet port...

Promote Your Company on RF Cafe for as Little as $40/mo.

Sponsor RF Cafe for as Little as $40 per Month - RF CafeRF Cafe typically receives 8,000-15,000 website visits each weekday and about half that on weekends. RF Cafe is a favorite of engineers, technicians, hobbyists, and students all over the world. With more than 13,000 pages in the Google search index, RF Cafe returns in favorable positions on many types of key searches, both for text and images. New content is added on a daily basis, which keeps the major search engines interested enough to spider it multiple times each day. Items added on the homepage often can be found in a Google search within a few hours of being posted. I also re-broadcast homepage items on LinkedIn. If you need your company news to be seen, RF Cafe is the place to be. Advertising begins at $40/month.

An Experimental Station on Wheels

An Experimental Station on Wheels, July 1935 QST - RF CafeThe high-tech vehicle you see here was state-of-the-art in 1935 when engineers at the Cruft Laboratory at Harvard University outfitted it to do radio research. The story appeared in QST magazine. The mission of the mobile unit is to enable laboratory equipment to be carried into the field to make observations on various radio phenomena. Clad with copper and chromium fittings, the vehicle contained transmitting and receiving equipment along with various test equipment that included a high stability frequency reference. In the article a "tungar" charger is mentioned. A tungar vacuum tube is a high current rectifier with a tungsten element and an argon gas filler...

Identifying Common vs. Differential Mode Noise

Optimizing EMI Input Filters for Switched Mode Power Supplies - RF CafeRhode & Schwarz has published a whitepaper entitled "Optimizing EMI Input Filters for Switched Mode Power Supplies," which includes an interesting analysis of differential mode versus common mode noise. "The conducted emissions of the converter where no filter components are applied is shown in Fig. 4-1. The top part of the measurement window illustrates the differential noise emissions (M1) whereas the bottom window shows the common mode noise (M2). The math which is required to distinguish between the two modes is set in the math channel menu and visible on the right. The time domain signals are not shown in detail in the main window because the frequency domain is the focus in this case study..."

Please Welcome NextPCB as a New RF Cafe Supporter!

NextPCB - RF CafeNextPCB is one of the most experienced PCB manufacturers in China, has specialized in the PCB and assembly industry for over 15 years. NextPCB provides the most innovative printed circuit boards and assembly technologies in the highest quality standards, turnaround time as fast as 24 hours, the lowest manufacturer direct prices, and the most dedicated customer service in the industry. Turnkey service without a broker including components sourcing, PCB prototyping, manufacturing, assembly, quality testing, and final shipment. Certified by IATF16949, ISO9001, ISO14001, UL, CQC, RoHS and REACH.

Radio Technology Theme Crossword Puzzle for January 17th

Radio Technology Theme Crossword Puzzle for January 17th, 2021 - RF CafeThis Radio Technology Theme crossword puzzle for January 17th contains only words and clues related to engineering, mathematics, chemistry, physics, and other technical words. As always, this crossword contains no names of politicians, mountain ranges, exotic foods or plants, movie stars, or anything of the sort unless it/he/she is related to this puzzle's technology theme (e.g., Hedy Lamarr or the Bikini Atoll). The technically inclined cruciverbalists amongst us will appreciate the effort. Enjoy!

Biggest "Portable" Radio

Biggest "Portable" Radio, July 1945 Radio-Craft - RF Cafe"Portable" is a matter of perspective when it comes to large systems. Anything that can be put on wheels and moved over land is technically portable, but the speed at which it can be brought into operation once relocated is what really defines whether something is portable or not. To be truly portable, all of the requisite support equipment must travel with it; e.g., electric generators, fuel, water, food, personnel facilities (if needed), etc. The MPN−14 portable airport surveillance radar (ASR) and precision approach radar (PAR) unit I worked on in the USAF truly qualified since it was entirely self-contained and the necessary power generators were supplied by a separate shop within the 5th Combat Communications Group to which I belonged. Other shops provided creature comfort facilities, ground-based and satellite radio communications, tactical air navigation (TACAN), security, and managerial services. A few times each year we had what were called "Healthy Strikes" where claxons would sound in the barracks...

CMT Webinar: Materials Measurement at 5G Frequencies

Copper Mountain Technologies Master Class Webinar: Materials Measurement at 5G Frequencies - RF CafeOn Wednesday, January 20th at 2:00 PM EST (GMT -5:00), Copper Mountain Technologies will present another of its VNA Master Class Webinar series entitled "Materials Measurement at 5G Frequencies." This webinar will demonstrate the use of free-space spot probes to characterize materials at 20 to 40 GHz, of interest to new 5G millimeter wave frequencies. A table-top measurement system using CMT's S5243 VNA will be used to determine transmission and/or reflection of materials. From these measurements, the webinar will discuss the calculation of dielectric properties of measured materials. The agenda consists of free space measurement description, example measurements & dielectric calculation and a Q&A session at the end...

Why Radio Astronomers Need Quiet in a WA Desert

Why Radio Astronomers Need Quiet in a WA Desert - RF CafeHa, I thought WA referred to Washington state, but not so. It's a good thing because I was going to accuse them of using a phony photo that includes the Large and Small Magellanic Clouds which are not visible from Washington! "A remote outback station about 800 km north of Perth in Western Australia is one of the best places in the world to operate telescopes that listen for radio signals from space. It's the site of CSIRO's Murchison Radio-astronomy Observatory (MRO) and is home to three telescopes (and soon a fourth when half of the Square Kilometre Array, the world's largest radio telescope, is built there). But it's important these telescopes don't pick up any other radio signals generated here on Earth that could interfere with their observations. That's why the observatory was set up with strict rules on what can and can't be used on site..."

Hi Tide in the Tweeter

Hi Tide in the Tweeter, October 1956 Popular Electronics - RF CafeBefore the current generation began destroying its hearing with smartphone earbuds, their parents and grandparents (that includes mine) destroyed our hearing with ridiculously powerful loudspeakers, often in boom boxes perched on shoulders right next to the ears (not me). The "concert hall" - or concert auditorium - experience has been long sought-after since recorded music has been available, which has only been about a century. As evidenced by the sudden increase in articles and advertisements in my growing collection of vintage electronics magazines, the early and mid 1950s saw a sudden swell of articles promoting the equally swelling supply of high fidelity (hi-fi) recording and playback equipment hitting the markets. Subjects ranging from homebuilt projects to reports of top end commercially products filled the pages each month. Television saw the same treatment in the late 1950s and early 1960s...

Qorvo Unleashes Full 6 GHz Performance with New Wi-Fi 6E FEMs

Qorvo® Unleashes Full 6 GHz Performance with New Wi-Fi 6E FEMs - RF CafeQorvo, a leading provider of innovative solutions that connect and power the world, today introduced two Wi-Fi 6E front end modules (FEMs) designed to maximize throughput and range in high-bandwidth applications such as 8K video streaming, online gaming and virtual reality. Wi-Fi 6E is an extension of Wi-Fi 6 that operates in the recently opened 6 GHz frequency band, in addition to the traditional 2.4 GHz and 5 GHz bands. Wi-Fi 6E triples Wi-Fi capacity with contiguous spectrum to accommodate 7 additional 160 MHz-wide channels or 14 additional 80 MHz channels. Qorvo's Wi-Fi 6E FEMs unleash the full potential of this new spectrum, delivering leading linearity performance and maximizing throughput and capacity at peak permissible indoor power levels...

Sprague Trading Post

Sprague Trading Post, August 1945 Radio-Craft - RF CafeHave you been looking for a Zenith Radio Nurse, a Superior Speedometer Multitester, or maybe a Clough Brengle 3" Oscilloscope? Perhaps you happen to have a wireless phono oscillator, a Weston 722 radio, or a Dumont 3" model 164E oscilloscope for sale. In either case, the Sprague Trading Post would have been the place to go in the mid 1940s, when the company paid good money in Radio-Craft magazine to host a swap shop for electronics hobbyists and professionals. Vacuum tubes, radios, test equipment, and related items were offered and requested. Sprague was/is a major manufacturer of capacitors, so they probably figured some of the equipment would need replacement capacitors which traders would buy from them...

withwave microwave devices - RF Cafe
Exodus Advanced Communications - RF Cafe Berkeley Nucleonics Academy RF Boot Camp - RF Cafe
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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...

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