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• USAF Air Force Holds EW Exercise with Classified Stealth Drone

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Apple Finds Itself on Wrong Side of Russia's Competition Rules

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Nokia's New CEO Working on Setting Strategy in "Dream Job"

Varian Associates Radar Illustrations by C.E.B. Bernard

Varian Associates Radar Illustrations by C.E.B. Bernard - RF CafeFrequent RF Cafe visitor who goes by the moniker "Unknown Engineer" sent me a hyperlink to a PDF file on Amazon's CloudFront* content delivery network (CDN - basically a file server) that contains no fewer than 17 amazing radar and vacuum tube related line drawings published by Varian Associates' TWT Division, Palo Alto Tube Division, Solid State Division, Eastern Tube Division, Western Tube Division, Solid State West Division. These highly detailed and busy drawings were done around 1975 by British illustrator/artist C.E.B. Bernard; a search for his works did not reveal much. The events shown are fictitious, as are the accompanying hand-printed stories. Some of the puns are pretty clever, but are somewhat dated for today's readers. To wit, the name Memamadun Ptolemy, which for the uninitiated is an allusion to the movie "Blues in the Night," where the actual words are "My momma done 'tol me..." (get it?). Another worthy mention is, "Tube V or not Tube V, that is the question," an obvious play on Shakespeare's "To be or not to be, that is the question" line by Prince Hamlet. If you recognize those, you'll find other familiar takeoffs as well...

Tiniest Secrets of ICs Revealed with Imaging Technique

Tiniest Secrets of ICs Revealed with Imaging Technique - RF Cafe"The life-givers of integrated circuits and quantum devices in silicon are small structures made from patches of foreign atoms called dopants. The dopant structures provide charge carriers that flow through the components of the circuit, giving the components their ability to function. These days the dopant structures are only a few atoms across and so need to be made in precise locations within a circuit and have very well-defined electrical properties. At present manufacturers find it hard to tell in a non-destructive way whether they have made their devices according to these strict requirements. A new imaging paradigm promises to change all that. The imaging mode called broadband electric force microscopy..."

Vintage College Engineering Labs

Vintage College Engineering Labs - RF CafeWhen I think back at the engineering labs from my days in school, I wonder how much things have really changed from then until now. It is hard to believe that freshman and sophomore labs are not still consumed with radial lead resistors, inductors, and capacitors, solderless breadboards, and a variety of light bulbs, motors, transformers, relays, and rheostats. By the time you move into the junior year, labs have gotten a bit more intense with microprocessor controls (mine used an 8088 CPU with machine language programming for the serial port), some high voltage apparati[sic], digital logic circuits, and a chance to lay out/fabricate/populate a PCB. On-hand test equipment consists of 2nd or 3rd generation oscilloscopes, signal generators, and power supplies. I did a search for photos of labs from back in the early to mid 1900s to see if much had changed from then until the time I was in college...

Apple Patents mm-Wave 5G Antenna that Radiates Through Display

Apple Patents mm-Wave 5G Antenna that Radiates Through Display - RF CafeOn July 28, 2020, Apple was granted patent number US10727570 entitled "Electronic devices having antennas that radiate through a display." Abstract: "An electronic device may be provided with a display and a phased array antenna that transmits radio-frequency signals at frequencies greater than 10 GHz. The display may include a conductive layer that is used to form pixel circuitry and/or touch sensor electrodes. A filter may be formed from conductive structures within the conductive layer. The conductive structures may include an array of conductive patches separated by slots or may include conductive paths that define an array of slots. The filter may include an additional array of conductive patches stacked under the array of conductive patches to allow the slots to be narrower than would be resolvable to the unaided human eye. The periodicity of the conductive structures and the slots...

Please Thank RF Superstore for Their Continued Support

RF Superstore coaxial cable, connectors, adapters - RF CafeRF Superstore launched in 2017, marking the return of Murray Pasternack, founder of Pasternack Enterprises, to the RF and microwave Industry. Pasternack fundamentally changed the way RF components were sold. Partner Jason Wright manages day-to-day operations, while working closely with Mr. Pasternack to develop RF Superstore into a world class RF and microwave component supplier. RF coaxial connectors & adapters, coaxial cable & cable assemblies, surge protectors, attenuators. Items added daily. Free shipping on orders over $25. We're leading the way again!

Heath Company: Heathkit Advertisement

Heath Company Heathkit, July 1955 Radio & Television News - RF CafeHeathkit's claim to fame was that it was able to offer user-assembled kits of high quality electronic products at a price lower than what equivalent factory assembled equivalents would cost. While that is probably generally the case, it is difficult to gauge what the relative quality really is. Some of the kits were easy to assemble for even people with little experience, but a good portion of them required familiarity with soldering and how electronics were put together. The instructions provided were very thorough, complete with photos and drawings of how each step should look. In fact, according to a 1972 installment of Mac's Service Shop entitled "Philosophy of a Kit Manufacturer," every Heathkit kit instruction booklet goes through a rigorous cycle of writing, testing, and rewriting before being released for production...

Practical Solutions for Measuring Phase Noise

Practical Solutions for Measuring Phase Noise - RF CafeAxiom Test Equipment, an electronic test equipment rental and sales company has published a new blog post entitled "Practical Solutions for Measuring Phase Noise" that examines phase noise, what it is, why too much noise and frequency instability can be a problem in testing, and how to find the right method and equipment for measuring it. Phase noise can often be measured directly using different measurement approaches such as residual and cross-correlation techniques, which are explored more in-depth in the blog. Most importantly, the blog explains what specifications to look for in a spectrum or signal analyzer to ensure the best fit for the job. A few equipment examples are given as guides...

Tracking Space Junk in Daylight

Tracking Space Junk in Daylight - RF Cafe"Scientists said they had discovered a way to detect space debris even in daylight hours, potentially helping satellites to avoid the ever-growing cloud of junk orbiting the planet. Defunct rockets, satellites and spacecraft parts continue to orbit Earth after they are discarded. The estimated 500,000 objects circling the globe range in size from a single screw to an entire rocket fuel tank. Travelling at thousands of miles an hour, they pose a huge and rising collision risk to satellites. Using lasers, it is possible to detect the debris from the ground..."

Building Your Own Audio Frequency Choke Coils

Building Your Own Audio Frequency Choke Coils, October 1932 Radio-Craft - RF CafeOne very satisfying aspect of 'rolling your own' audio frequency coils (aka chokes, aka inductors), is how well the simple inductance equations match measured end results. Unless you really manage to mangle the job, if you use the right equation and are reasonably careful to observe wire size, spacing (including insulation), and core diameter, you will be amazed at how close practice matches theory. Although strictly speaking audio frequencies run from a few Hertz up to maybe 15 kHz for people with really good hearing. My experience is that similar success can be had even into the low MHz realm with just a little tuning required. It's not until you get into the realm of self-resonance that everything starts falling apart...

Anatech Electronics Intros 2 New Cavity Filters

Anatech Electronics Intros 2 New Cavity Filters - 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. The P/N AE1200-1400DB5450 passes DC-1200 MHz and 1400-3000 MHz with a crossover insertion loss of 5 dB at 1300 MHz crossover frequency at 1300 MHz and in band insertion loss of less than 1 dB. The AE2310B11640 passes the LTE band of 2305-2315 MHz with an in-band insertion loss of less than 1 dB. The 2305-2315 MHz bandpass filter exhibit a very sharp transition to the rejection band with a power...

Many Thanks to Reactel for Their Long-Time Support!

Reactel Filters - RF Cafe

Reactel has become one of the industry leaders in the design and manufacture of RF and microwave filters, diplexers, and sub-assemblies. They offer the generally known tubular, LC, cavity, and waveguide designs, as well as state of the art high performance suspended substrate models. Through a continuous process of research and development, they have established a full line of filters of filters of all types - lowpass, highpass, bandpass, bandstop, diplexer, and more. Established in 1979. Please contact Reactel today to see how they might help your project.

Urgent Need !!!

Cree CMPA0060025F - RF CafeAn engineer friend wrote saying he is in immediate need of 50 pieces of the Cree CMPA0060025F, 25 W, 20-6000 MHz, GaN MMIC power amplifier. If you can supply any quantity, please contact me at kirtrfc@aol.com to let me know. Time is of the essence. Thank you very much!

Electronic Crossword Puzzle

Electronic Crossword Puzzle, September 1958 Radio & TV News - RF CafeThis "Electronic Crossword" appeared in the September 1958 issue of Radio & TV News magazine. Its creator, John Gill, designed specialty theme crossword puzzles for many other editions of Radio & TV News and Electronics World (see the big list at the bottom of the page). He considered this crossword to be a "fooler" because he claims to include many "unusual definitions and a number of obscure words which you will have to work around if your vocabulary of 'exotic words' is rusty." It really doesn't seem so difficult to me, and anyone used to working my custom RF Cafe Crosswords will have no problem with it.

Skyworks High Linearity LNAs for Small Cell, Massive MIMO and Base Stations

Skyworks High Linearity LNAs for Small Cell, Massive MIMO and Base Station Applications - RF CafeTo meet the challenging requirements of cellular LTE and 5G NR infrastructure applications, Skyworks has released the SKY67183−396LF and SKY67189−396LF low noise amplifiers (LNAs). These LNAs feature ultra low-noise figure, exceptional linearity, and operate over a wide range of frequencies. To reduce PCB board space, these devices are housed in an ultra-compact 2 x 2 mm plastic surface mount package. The SKY67183−396LF and SKY67189−396LF are ideal for 2G/3G/4G/5G TDD and FDD infrastructure applications, including small cell, massive MIMO, and macro base...

Astra Small Satellite Launcher Test Flight from Alaska

Astra Small Satellite Launcher Test Flight from Alaska - RF Cafe"After completing a countdown dress rehearsal, Astra is gearing up for its first orbital launch attempt this week from Kodiak Island, Alaska, but company officials said it will likely take multiple test flights before the new small satellite launcher successfully reaches orbit. Astra's small satellite delivery vehicle was set for liftoff from the Pacific Spaceport Complex in Alaska during a two-hour window opening at 10 p.m. EDT Sunday, or 6 p.m. local time in Alaska. In social media updates, Astra said it fueled the small satellite launcher with liquid propellants Sunday. But officials said out-of-limits upper level winds and a boat in restricted waters offshore..."

Transmission-Line Feed for Short-Wave Antennas

Transmission-Line Feed for Short-Wave Antennas, October 1932 QST - RF CafeWhen someone with the first name of "True" writes an article about transmission line feeds for short-wave antennas, you should probably take note. This very topic has been covered in detail many times since the use of impedance-matched transmission lines have been in use (more than a century), but since there are always people new to the concept, it is good to keep introducing the topic on a regular basis."Transmission-Line Feed for Short-Wave Antennas" appeared in a 1932 issue of QST magazine. Even in this era of prefabricated everything, it still often comes down to winding coils and adjusting cable lengths to get optimal impedance matches between transceivers and antennas.

Vanadium: The Other Green Metal

Vanadium: The Other Green Metal - RF CafeI have extolled the virtues of Aerospace & Defense Technology magazine many times for its variety of extremely interesting articles on a wide range of topics. The August issue has a story on the element Vanadium (atomic number 23) and the critical role it plays as an alloy component of metals. At concentrations of less then 0.1%, vanadium can nearly double the strength of steel and aluminum, as well as increasing resistance to corrosion. It is also used as a catalyst (sometimes a substitution for nickel and platinum), in electronics components, and in ceramics. Use of vanadium is considered "green" because most of it is obtained from byproducts of other industrial processes like ash from coal burning. Vanadium is the earth's 22nd most abundant element and is found everywhere, but as you might suspect China provides 61% of the supply while the U.S. does a mere 3% (Russia makes 14%). Fortunately, part of the Dept. of Interior's 2018 charter was to include vanadium on its list of critical commodities and must act to significantly increase domestic production rather than be dependent on foreign sources. It's long past time.

ConductRF Performance TSA89 Flexible RF Test Cables to 40 GHz

ConductRF Performance TSA89 Flexible RF Test Cables to 40 GHz - RF CafeManufacturing of all our products continues to operate at full capacity as part of the "Essential Business" community. Professional high frequency TSA89 series of RF test cables with performance to 40 GHz. Precision connector choices include; SMA, Type-N, 3.5mm, 2.92mm, & 2.4mm. Key features: High-frequency point to point cable, light weight rugged double-shielded, flexible cable, low loss <0.68 dB/ft @ 40 GHz, low VSWR < 1.35:1 (Typical < 1.25:1), RF leakage >−100 dB to 18 GHz, temperature rated from -55ºC to 125ºC. 100% factory VSWR and insertion loss tested. Cables are in stock and available immediately from Digi−Key. Made in the USA.

Anatech Electronics (RF Filters) - RF Cafe MPDevice microwave devices - RF Cafe
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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...

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