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"It is wise to remember that you are one of those who can be fooled some of the time." - Laurence Peter (The Peter Principle)

Today in Science History

微信扫雷平台tech industry headlines

Tech Industry Headlines - RF Cafe- Archive -

• raises $3.2b

微信扫雷平台• eu commission updates lists of

• head to vote

微信扫雷平台• successful test reported

• nrl golden touch

• call its small cell rules a "land-grab"

• about quantum uncertainties

微信扫雷平台• : a catalyst to change?

• arrl creates

milestone in space communication

Milestone in Space Communication, February 1973 Popular Electronics - RF CafeIn 1971 the International Telecommunications Union (ITU), convened a meeting dubbed the World Administrative Radio Conference for Space Telecommunications (WARC-ST). The ITU was a specialized agency of the United Nations for telecommunications, with a membership of 140 nations. Satellite communications was barely a decade old, but already the need for international agreements on spectrum usage had become very apparent. Prior to the 1971 meeting, there was the 1963 Extraordinary Administrative Radio Conference held in Geneva, Switzerland. Amateur radio had its presence in the game acknowledged with further allocations for its members' OSCAR birds; six had been flown already. As of this writing there are about 20 OSCAR satellites still in operation. Amateur satellites take many forms these days, including the newest trend in CubeSat platforms with a well-defined set of specifications on dimensions and mass per cube. Launches are provided on a space available basis at a substantially discounted cost...

微信扫雷平台copper mountain technologies partners with purdue university

Copper Mountain Technologies Becomes Corporate Partner of Purdue University - RF CafeTo help grow the next generation of RF Engineers, Copper Mountain Technologies (CMT) has become a corporate partner with the Purdue University Electrical and Computer Engineering (ECE) Program in West Lafayette, Indiana. The mission of CMT is to extend the reach of engineers by providing vector network analyzers that are portable, accessible, and affordable. By partnering with Purdue, we hope to promote growth in the increasingly important field of RF engineering. Despite a recent rise in engineering students and degree options, there is a shortage of RF engineers. With the abundance of wireless and IoT devices being created around the world, the requirement for engineers researching, designing, and working with these devices has grown and the demand for these professionals is not being met. There is a wide range of job opportunities for RF engineers in industries...

hams in combat -one life to give

Hams in Combat - One Life to Give, July 1944 QST - RF CafeQST did a regular series of articles titled "Hams in Combat" during World War II. This story is unique in nature in that it tells of a newspaperman-turned-soldier who, in the story writer's mind, would have been the most suited for the job of author. It tells a far different story of the South Pacific than we were treated to in weekly episodes of McHale's Navy! "Had this story been written by the man who should have written it - Capt. William H. Graham, W9BNC - it would have been one of the greatest "Hams in Combat" yarns ever told in these pages. But Bill Graham never got around to writing his story. He was too intensely occupied with the living of it - too keenly aware of the new paragraph... Note the letter I received from Capt. Graham's great grandson.

improving 5g network security

Improving 5G Network Security - RF Cafe微信扫雷平台"Emerging technologies are slated to dramatically increase in both scale and speed, enabling much faster access to data collected from billions of connected devices. This supercharged information highway is envisioned to play an important role across several industries, ranging from medicine to manufacturing. Major advances in 5G, including new core network features will make it easier to customize the network at a wide variety of locations. This new flexibility offers many benefits, but at the same time introduces novel security challenges. Today's proprietary 5G technologies make it difficult to achieve the transparency necessary for security-related risk analysis and mitigation. This lack of security assurance makes it harder..."

how to derive -40°f = -40°c

How to Derive -40°F = -40°C - RF Cafe UniversitySome of what you and I consider common knowledge is largely unrealized by most people. Call me a geek, but I take pleasure in pointing out to people that the Fahrenheit and Centigrade scales are equal at -40°, and I especially enjoy working out the simple proof for them. Most people appreciated the effort and are amazed, claiming to have never seen that before. When I read the following in Smithsonian magazine, "Winter temperatures here, some 250 miles northeast of St. Petersburg, sometimes plunge to minus 40 degrees Fahrenheit," I wondered whether the author knew that -40°F = -40°C. Maybe he just didn't want to confuse his readers by omitting the redundant superfluous 'F' or 'C,' and it couldn't be 'K' because there are no negative Kelvin degrees. It could also be that he knew but figured most people do not...

custom mmic: off-the-shelf and custom mmics

Custom MMIC- RF CafeCustom MMIC is a entrusted by government and defense industry OEMs. Custom and off-the-shelf products include switches, phase shifters, attenuators, mixers and multipliers, and low noise, low phase noise, and distributed amplifiers. From next-generation long range military radar systems, to advanced aerospace and space-qualified satellite communications, microwave signal chains are being pushed to new limits - and no one understands this more than Custom MMIC. Please contact Custom MMIC today to see how they use their modern engineering, testing and packaging facility to help your project. 

a new approach to beam antennas

A New Approach to Beam Antennas, February 1950 Radio & Television News - RF CafeThis article describes a method for tuning beam antennas from the ground rather than needing to experiment with matching capacitors and/or inductors at the antenna end of the transmission line. The scheme uses a separate length of transmission line attached to the reflector element at a length an integer number of half-wavelengths as required to reach the ground. That way, tuning elements can be installed and adjusted for one or more bands without needing to climb up to the antenna. The method can be used for any number of elements, but of course it could get a bit messy with more than a couple. The author, Major Charles E. Spitz (W7JHS), describes using a field strength meter to verify tuning correctness. Having read many QST magazine articles on antennas over the past decade or so...

微信扫雷平台post your engineer & technician job openings on rf cafe for free

Engineering Job Board - RF CafeRF Cafe's raison d'être is and always has been to provide useful, quality content for engineers, technicians, engineering managers, students, and hobbyists. Part of that mission is offering to post applicable job openings. HR department employees and/or managers of hiring companies are welcome to submit opportunities for posting at no charge (of course a gratuity will be graciously accepted). 3rd party recruiters and temp agencies are not included so as to assure a high quality of listings. Please read through the easy procedure to benefit from RF Cafe's high quality visitors...

atoms can receive common communications signals

Atoms Can Receive Common Communications Signals - RF Cafe微信扫雷平台"Researchers at the National Institute of Standards and Technology (NIST) have demonstrated a new type of sensor that uses atoms to receive commonly used communications signals. This has the potential to be smaller and work better in noisy environments than conventional radio receivers, among other possible advantages. The NIST team used cesium atoms to receive digital bits (1s and 0s) in the most common communications format, which is used in cell phones, Wi-Fi and satellite TV, for example. In this format, called phase shifting or phase modulation, radio signals or other electromagnetic waves are shifted relative to one another over time. The information (or data) is encoded in this modulation..."

微信扫雷平台90° hybrid coupled power amplifier pros and cons

90° Hybrid Coupled Power Amplifier Pros and Cons - RF CafeAn app note entitled "90° Hybrid Coupled Power Amplifier Pros and Cons微信扫雷平台," by NuWaves Engineering's Justin Wells, appeared in the latest edition of magazine. Mr. Wells has authored other app notes that, like this one, does a good job of distilling complex topics into articles understandable by newcomers to the RF trade. It begins, "Power Amplifiers (PAs) are commonplace in radio frequency (RF) systems extensively used in applications consisting of over-the-air wireless communications. Wireless communications is a broad market and PAs fill a wide array of those applications. Due to the broad range of applications, PA design techniques must be chosen carefully for each application-specific scenario. Single-ended PAs have limitations that restrict their practicality in many applications, especially where higher output power..."

微信扫雷平台teledyne 2 in 1 dual l/s-band sspa for satcom c&c

Teledyne Paradise Datacom 2 in 1 Dual L/S-Band SSPA for Satcom Command & Control - RF CafeTeledyne Paradise Datacom, part of the Teledyne Defense Electronics Group, today announced the wide availability of a new, leading edge L- and S-Dual Band solid state power amplifier微信扫雷平台 (SSPA) for today's evolving satellite command systems. Both S- and L-band frequencies have been the industry's bands of choice for positioning and tracking applications like global positioning systems (GPS) and Tracking, Telemetry, and Control (TTC) ground stations. This new dual band product offers customers a virtual "two for the price of one" SSPA solution that dramatically lowers the costs of command and control, leaves a much smaller footprint, but also delivers higher reliability compared to traditional klystron power amplifiers...

nova microwave: rf & microwave circulators & isolators

Nova Microwave Circulators & Isolators - RF CafeNova Microwave is a leader in technically differentiated electronic and radio frequency Ferrite Circulators and Isolators that connect, protect and control critical commercial and military wireless telecommunications systems. Our staff is dedicated to research and development of standard and custom design quality Ferrite Circulators and Isolators from 380 MHz to 26.5 GHz. Available in single or multi-junction topographies, the Nova Microwave product line of is specifically designed for use in varied environmental and temperature extremes. 

jury told of fraud in radio telephone (1917 nyt)

Jury Told of Fraud in Radio Telephone (New York Times - Thursday, November 27, 1913) - RF CafeMotivated by the series of articles about Lee de Forest in the January 1947 issue of Radio-Craft magazine, I did a search of U.S. newspapers from 1905 through 1947 looking for news items on him. In particular, I was hoping to find something about the lawsuit levied by the Marconi Company against Lee de Forest wherein the judge was reported to have told him, "...to forever desist from the manufacture, sale or operation of any system of wireless telegraph." Alas no such information was discovered, but the search will continue. I did find this piece and many other interesting items that will be posted as time permits. Here, Mr. de Forest sued, with the assistance of the U.S. Government, an investment company for defrauding investors in regard to company stock sales, using a charge of mail fraud to assist in prosecution. Mail fraud, tax evasion, interstate commerce and other such non-state related charges were (and still are) routinely used by the Feds...

electronic wrist-watches

Electronic Wrist-Watches, February 1973 Popular Electronics - RF CafeTry as I did, I could not find any instance of the Ness Clocks all-digital liquid crystal display (LCD) desktop clock which appeared in this 1973 Popular Electronics article. There must not have been many produced. LCDs had only been commercially available for a year or so when this went on sale. Of the relatively few digital display clocks and watches available in the 1970s, the vast majority used light-emitting diodes (LEDs), and most sold for north of $100 (~$600 in today's money). Portable devices with digital displays really began to flourish with the advent of both CMOS circuitry and LCD displays; i.e., low current devices that extended battery life. Wrist watches, which could only accommodate very small batteries with limited energy storage capacity, were amongst the greatest beneficiary...

transistors both process and store information

Transistors Both Process and Store Information - RF Cafe微信扫雷平台"A computer chip can using two different devices. If these devices could be combined into one or put next to each other, there would be more space on a chip, making it faster and more powerful. Engineers have developed a way that the millions of tiny switches used to process information (transistors) could also store that information as one device. The method accomplishes this by solving another problem: combining a transistor with higher-performing memory technology than is used in most computers, called ferroelectric RAM. Researchers have been trying for decades to integrate the two..."

vita67.3 nano miniature rf cables for vpx systems

VITA67.3 Nano Miniature RF Cables for VPX Modular Systems - RF CafeConductRF's close partnership with TE in its development of its new Nano-miniature RF Solutions for VITA67.3 has put us in a great position to support your VPX RF cable assembly needs. Modular solution supports 8 to 18 positions, flexible 0.047" diameter cable, supports frequency up to 70 GHz, use with standard solutions (SMA, SMPM, etc.), 2x density of Vita67.1. ConductRF's PFT33 Series of Micro Flexible Cable Assemblies has been designed directly with TE Connectivity involvement and in partnership to maximize the capabilities of TE's new Vita67.3 NanoRF VPX modular connector system. ConductRF offers its soft FEP jacketed ø0.047" cable to facilitate maximum flexibility and provides solutions for jumper cables ...

rf cascade workbook 2018

RF Cascade Workbook 2018 Is Available Now! - RF CafeRF Cascade Workbook 2018 is the next phase in the evolution of RF Cafe's long-running series, RF Cascade Workbook. It is a full-featured RF system cascade parameter and frequency planner that includes filters and mixers for a mere $45. Built in MS Excel, using RF Cascade Workbook 2018微信扫雷平台 is a cinch and the format is entirely customizable. It is significantly easier and faster than using a multi-thousand dollar simulator when a high level system analysis is all that is needed. An intro video takes you through the main features...

微信扫雷平台pcb directory: printed circuit board fabrication & assembly

PCB  Directory - RF CafePCB Directory is the largest directory of Manufacturers, Assembly houses, and Design Services on the Internet. We have listed the leading printed circuit board manufacturers around the world and made them searchable by their capabilities - Number of laminates used, Board thicknesses supported, Number of layers supported, Types of substrates (FR-4, Rogers, flexible, rigid), Geographical location (U.S., China), kinds of services (manufacturing, fabrication, assembly, prototype), and more. Fast turn-around on quotations for PCB fabrication and assembly.

lee de forest - father of radio

Lee de Forest - Father of Radio, January 1947 Radio-Craft - RF CafeLee de Forest, upon whom was conferred the honorary title "Father of Radio" by Radio-Craft editor Hugo Gernsback (and others), exemplifies personal traits of most great inventors: high intelligence, stick-to-itiveness, courage, passion for his subject, determination, and a willingness to endure a lot of personal and financial abuse. The January 1947 issue of Radio-Craft magazine celebrated the 40-year anniversary of Mr. de Forest's invention of the Audion vacuum tube by including a large number of articles by various authors who knew him personally and attest to his greatness. I will be posting a few of those pieces, and you will probably be shocked at some of the shenanigans that went on by conniving people and naysayers who tried to deny de Forest due credit. For example, based on his work to make more sensitive receivers a judge in a lawsuit brought by Marconi strictly enjoined him "to forever desist from the manufacture, sale or operation of any system of wireless telegraph...

ERZIA (RF amplifiers, wireless, communications) - RF Cafe PCB Directory (Manufacturers)
vidaRF Isolators & Circulators - RF Cafe
About RF Cafe
Kirt Blattenberger - RF Cafe Webmaster
Copyright: 1996 - 2024
Webmaster:
    Kirt Blattenberger,
    BSEE - KB3UON

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 Internet was still largely an unknown entity at the time and not much was available in the form of WYSIWYG ...

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