Homepage Archive - October 2020 (page 4)

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Wednesday 28

Housewives and Television

Housewives and Television, October 1947 Radio-Craft - RF CafeContrary to the scenario presented in this light-hearted mockery of housewives attempting to assemble some electronics kits, there were actually many women during the height of the radio and television age who were quite adept at handling soldering irons and test equipment. In fact, the case could be made that, given the 1947 appearance of this "Housewives and Television" piece in Radio-Craft magazine, women of the post-wartime industrial period were probably the most experienced and adept assemblers of electronics equipment. After all, it was Rosie the Riveter who built airplanes, ships, and tanks while Sally the Solderer built the bulk of the tens of thousands of radios, radars, sonars, medical and test instruments, vacuum tubes, amplifiers, and other electronics while the brothers...

Please Visit in Appreciation 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.

Zeptoseconds: New Record in Short Time Measurement

Zeptoseconds: New Record in Short Time Measurement - RF Cafe"In 1999, the Egyptian chemist Ahmed Zewail received the Nobel Prize for measuring the speed at which molecules change their shape. He founded femtochemistry using ultrashort laser flashes: the formation and breakup of chemical bonds occurs in the realm of femtoseconds. Now, atomic physicists at Goethe University in Professor Reinhard Dörner's team have for the first time studied a process that is shorter than femtoseconds by magnitudes. They measured how long it takes for a photon to cross a hydrogen molecule: about 247 zeptoseconds for the average bond length of the molecule. This is the shortest timespan..."

Theory and Construction of Attenuators, Line Filters and Matching Transformers

The Theory and Construction of Attenuators, Line Filters and Matching Transformers, June 1932 Radio-Craft - RF CafeIt seems most of the articles we see on the subject of attenuator pads are based on signal reduction in terms of decibels for units of power. Although it is a simple matter to convert power decibels to voltage decibels, it would be more convenient if you are working with voltage to have formulas and tables of values based on voltage ratios. This article does just that. As a reminder, the decibel representation of a ratio is always 10 * log10 (x). If you have a voltage ratio of V1/V2 = 0.5, then 10 * log10 (0.5) = -3.01 dB. If you have a power ratio of P1/P2 = 0.5, then 10 * log10 (0.5) = -3.01 dB. Does that mean that -3.01 dB of voltage attenuation is the same as 3.01 dB of power attenuation? Confusingly, no. Let's say for the sake of simplicity that you have 1 V across a 1 Ω resistor...

Nokomis Looking for an RF/Electrical Mixed Signal Engineer

Nokomis Looking for an RF/Electrical Mixed Signal Engineer - RF CafeNokomis Inc., is a high technology research and development company located just south of Pittsburgh, PA. Nokomis does cutting-edge technology work for the Department of Defense (DoD) and other Government Agencies. We rank in the top 3 for entities under 300 employees in the state of Pennsylvania for the number of R&D contracts we typically win yearly. The candidate should be comfortable executing on and potentially leading multiple projects. This position requires a multi-disciplined Senior Electrical Engineer, capable of solving complex technical problems and providing innovative solutions in the areas of Electrical Engineering and the part, board and system level to develop the most sensitive Radio Frequency (RF) systems on the planet. Though candidates with specialized experience in digital design, analog design mixed signal design or RF design will be considered as each of these disciplines is required. The ideal candidate will have an understanding of and experience with digital, analog, mixed signal and RF systems...

Many Thanks to Exodus Advanced Communications for Their Support

Exodus Advanced Communications - RF CafeExodus Advanced Communications is a multinational RF communication equipment and engineering service company serving both commercial and government entities and their affiliates worldwide. Power amplifiers ranging from 10 kHz to 51 GHz with various output power levels and noise figure ranges, we fully support custom designs and manufacturing requirements for both small and large volume levels. decades of combined experience in the RF field for numerous applications including military jamming, communications, radar, EMI/EMC and various commercial projects with all designing and manufacturing of our HPA, MPA, and LNA products in-house.

Tuesday 27

Electronics-Themed Comics, 1953 Radio-Electronics

Electronics-Themed Comics, November 1953 Radio-Electronics - RF CafeIt's about time for a little joviality so here are the three technology-themed comics which appeared in the November 1953 issue of Radio-Electronics magazine. They cover a wide range of situations experienced by electronics types back in the day, including the fickleness of customers, an exaggeration of an explorer's unexpected discovery deep in a jungle, and the frustrated indignation of a parts supplier by the selective memory of a serviceman in need of replacement components. Enjoy!

Withwave Intros Vertical Launch 1.0 mm Connector (DC to 110 GHz)

Withwave Intros Vertical Launch 1.0 mm Connector (DC to 110 GHz) - RF CafeWithwave announces the introduction of Vertical Launch Connectors which are specially designed for solderless vertical PCB launch on test & measurement board. These connectors have excellent electrical transition performance up to 26.5 GHz, 50 GHz, 67 GHz & 110 GHz respectively as well as reduce installation time by eliminating soldering. Excellent vertical transition (VSWR <1.3, 1.85 & 1.0 mm type: VSWR <1.6 ). ANSYS HFSS models available (version 17.0 or newer) for 3D EM (electromagnetic) simulation...

Reducing Risk & Improving Quality of Military Radar Receivers

Reducing Risk & Improving Quality of Military Radar Receivers - RF Cafe"An industry-leading military radar receiver manufacturer needed to deliver radar receivers that met tough new customer specifications. To ensure a quality product, the manufacturer reviewed many aspects of its test strategy, focused on ensuring its radar receivers could meet the new specifications. Radar receiver sensitivity is critical for electronic warfare (EW) applications. A radar receiver that is outside specifications will fail to decipher signals properly from long distances. This is not an option in military applications. Risk of false passes. The aerospace and defense manufacturer needed to improve receiver sensitivity and the accuracy of its power level measurements in order to meet its design specifications and cost goals..."

Many Thanks to Nova Microwave for Continuing Support!

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. 

Quiz #40: Introduction to Antenna Analysis Using EM Simulation

RF Cafe Quiz #40: Introduction to Antenna Analysis Using EM SimulationThis quiz is based on the information presented in Introduction to Antenna Analysis Using EM Simulation, by Hiroaki Kogure, Yoshie Kogure, and James C. Rautio, published by Artech House. It is written for novice engineers and engineering students. This easy-to-comprehend resource offers readers thorough introductory-level treatment of antenna analysis using electromagnetic (EM) simulators. This richly-illustrated book shows how to use EM software to analyze and tune wireless antennas to meet specific requirements. Readers learn important wireless antenna design terminology and gain a detailed understanding of how antennas work. Moreover, the book offers guidance in troubleshooting problems with wireless antenna designs...

BNC Webinar: Low vs. High-Resolution Detectors

BNC Webinar: Low vs. High-Resolution Detectors (Free Admission) - RF CafeBerkeley Nucleonics Corporation (BNC - like the connector) is excited to announce that our upcoming live webinar, "Low vs. High-Resolution Detectors," is less than one week away! Demystify high-resolution Scintillation with Berkeley Nucleonics and special guest Paul Schotanus from Scionix as we dive into the current landscape of high-resolution detectors in the 662 KeV Gamma range: CeBr3, LaBr3, SrI2, CLYC, and GAGG. To accommodate for time differences, we will be hosting two sessions with the same topics and agenda. Please register for the time slot that works best for you. U.S. Event - Wednesday, October 28th, 2020 @ 10:00 AM PST...

Thanks to PCBONLINE for Continued Support!

PCBONLINE - RF CafePCBONLINE supplies complex rigid and flex-rigid printed circuit boards (PCBs),and one-stop production with maximum flexibility ranging from prototype sample to mass production. Rigid-flex, HDI, multilayer, IC-loadboard, LCP 5G optical module, ceramic, MCPCB. Materials include Rogers, Taconic, Arlon, Isola, Bergquist, Kapton, Panasonic, and more. After more than 15 years of continuous efforts, PCBONLINE constantly updates our equipment, improves our technology, and serves you with the highest quality. Cost and delivery quotations online without the need for multiple phone call and/or e-mails.

Monday 26

Tube Testers for Speedy Checking

Tube Testers for Speedy Checking, October 1955 Radio & Television News - RF CafeIt's a pretty good bet that most RF Cafe visitors are not overly interested in vacuum tube testers. Today they are collectors' items with some actually still being used for maintaining vintage electronics gear; however, in the days before semiconductor components they were the life blood of service men. Because tubes (aka "valves" in other parts of the world) are by nature one of the most vulnerable parts of any product in which they are used, often the first step in troubleshooting a radio, television, record player, etc., was to test suspected tubes for sub par performance. As mentioned often in Mac's Radio Service Shop stories, customers balked at service centers charging for their expertise but didn't mind as much paying for replaced components. That meant mark-ups on vacuum tubes comprised...

Nokomis Looking for an Engineering Manager

Nokomis Looking for an Engineering Manager - RF CafeNokomis Inc., is a high technology research and development company located just south of Pittsburgh, PA. Nokomis does cutting-edge technology work for the Department of Defense (DoD) and other Government Agencies. We rank in the top 3 for entities under 300 employees in the state of Pennsylvania for the number of R&D contracts we typically win yearly. We are seeking a versatile Engineering Manager that can apply their skills and experience to a wide array of design challenges and produce results that enhance the company's product offerings. In this role, you will be responsible for utilizing your industry knowledge to oversee a variety of activities. You will also be responsible for ensuring that key projects and engineering duties are fulfilled, and for solving any engineering issue that comes up in a project...

Transmission Lines

Transmission Lines, August 1944, Radio-Craft - RF CafeIs there such as thing as too many articles on transmission lines? I think not, at least for most visitors to RF Cafe. Since the fundamentals of transmission lines have not changed in the last century, it really doesn't matter when an article was written. This one covers the basics of impedance and wavelength, and then delves briefly into the subjects of antenna feeder transmission lines and using transmission lines as impedance transformers. As with most topics these days, there are many software programs available that will calculate parameters for you, but successful setup and operation requires a solid understanding of what is happening with your electronic gear, antennas, and the transmission lines that provide the interfaces...

CMT Intros 43-5 GHz, 2-Port Vector Network Analyzer

Copper Mountain Technologies Intros 43-5 GHz, 2-Port Vector Network Analyzer - RF CafeCopper Mountain Technologies, a leading developer of innovative RF test and measurement solutions for engineers all over the world, has introduced a new 2-port 43.5 GHz vector network analyzer (VNA). Model S5243 is CMT's highest frequency Compact VNA. It features excellent dynamic range and fast measurement speed in a compact package with the maximum standard software feature set. S5243 VNA includes an RF measurement module and S2 Windows or Linux operating system on a PC, laptop, tablet, or x86 board computer connecting to the measurement hardware via USB interface. S2 software can be installed on multiple computers, making it easy to share the use of the analyzer...

Many Thanks to Qorvo / Custom MMIC for Their Continued Support

Qorvo / Custom MMIC- RF CafeQorvo / Custom MMIC is a fabless RF and microwave MMIC designer 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 Qorvo / Custom MMIC today to see how they use their modern engineering, testing and packaging facility to help your project. 

Sunday 25

Radio Engineering Themed Crossword Puzzle for October 5th

Radio Engineering Themed Crossword Puzzle for October 25th, 2020 - RF CafeOctober 25th's custom Radio Engineering Technology themed crossword puzzle contains only only words from my custom-created lexicon related to engineering, science, mathematics, chemistry, physics, astronomy, etc. (1,000s of them). You will never find among the words names of politicians, mountain ranges, exotic foods or plants, movie stars, or anything of the sort. You might, however, find someone or something in the otherwise excluded list directly related to this puzzle's technology theme, such as Hedy Lamarr or the Bikini Atoll, respectively. The technically inclined cruciverbalists amongst us will appreciate the effort...

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. Chances are you have never used a spreadsheet quite like this. 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 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

Friday 23

Oscilloscope Patterns and Amplifier Diagnosis

Oscilloscope Patterns and Amplifier Diagnosis, October 1953 Radio-Electronics - RF CafeAn ability to interpret the display on an oscilloscope is absolutely essential to efficiently diagnose a circuit when troubleshooting. In the days of an electronics repair shop in every town when televisions, radios, phonographs, tape recorders, and other consumer gizmos were actually meant to be repaired rather than thrown away and replaced, technicians needed to be able to compare a measured signal to the one represented in the factory service manual, or what was known from experience to be the expected signal. Especially with TV where complex analog broadcast signals were decoded and routed to circuits for stereo audio, red, green and blue color channels, scan synchronizations, and other functions, phase shifts and signal distortion caused by any number of component failures or parameter changes could be very difficult to troubleshoot. If you have read some of the "Mac's Radio Service Shop" episodes...

Anode Allows for Safe Battery Recharge in Minutes

Anode Allows for Safe Battery Recharge in Minutes - RF Cafe"Researchers at UC San Diego may have found a solution that enables lithium-ion batteries to be safely recharged within minutes for thousands of cycles. Quick battery recharge is something scientists are constantly working on as people get more and more dependent on their electronic devices. Now researchers at UC San Diego may have found a solution in a new anode material that enables lithium-ion batteries to be safely recharged within minutes for thousands of cycles. The material is a disordered rock salt, which is comprised of earth-abundant lithium, vanadium, and oxygen atoms..."

A Radioman's Nightmare

A Radioman's Nightmare, March 1945 QST - RF CafeJust in time for Halloween: "A Radioman's Nightmare" - another sampling of electronics poetry, circa 1945... BTW, for those unfamiliar with "Mairzy Doats," the song is a comical slurring of words that make new, nonsensical words in the process. 'Mairzy Doats', for instance, is a slurring of 'Mares Eat Oats,' 'And Liddle Lamzy Divey' is really 'And Little Lambs Eat Ivy." "Mairzy Doats" was written in 1943...

AWR Software V15 Playlist on AWR.TV YouTube Channel

New AWR Software V15 Playlist Now Available for Viewing on AWR.TV YouTube Channel - RF CafeA new AWR.TV video playlist features seven videos that enable users to take a deep dive into the key features in the V15 release of Cadence® AWR Design Environment® software. The V15 videos highlight: New and improved antenna measurements for peak power, including direction, total power, and amount of power radiated in peak direction. Driving circuitry in calculations can also be included. New electromagnetic (EM) features in the AWR® AXIEM® and Analyst™ simulators. AXIEM software offers improved meshing with fewer high-aspect ratio facets (HARFs), a true DC solver for biasing that is 40X faster and sub nanometer meshing for metal-insulator-metal (MIM) capacitors...

Many Thanks to Nova Microwave for Continuing Support!

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. 

Thursday 22

A New Memory Device

A New Memory Device, October 1953 Radio-Electronics - RF CafeRadio-Electronics magazine ran a regular industry news column entitled "The Radio Month." The headline item in the December 1949 issue was the emergence of a new type of digital memory device using nearly microscopic magnetic toroidal coils with a matrix of even tinier wires threaded through them in order to write and read 1's and 0's. RCA created this 10,000-bit magnetic core memory assembly in order to overcome the size and speed limitations of alternate methods available in the day - primarily mercury-based delay lines. UNIVAC II, commissioned in 1958, was the first major digital electronic computer to use this magnetic core memory, but given that transistor development was still in its infancy, vacuum tubes were used to address...

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. 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...

U.S. Space Development Agency Awarded Contracts for 1st Gen Tracking Layer

U.S. Space Development Agency Awarded Contracts for 1st Gen Tracking Layer - RF Cafe"SDA announced October 5 two contract awards for the first generation of the Tracking Layer. These awards represent the next major and highly visible steps toward developing the National Defense Space Architecture's inaugural tranche (called Tranche 0). Once fully operational, the SDA Tracking Layer will consist of a proliferated heterogeneous constellation of Wide Field of View (WFOV) space vehicles (SVs) that provide persistent global coverage and custody capability combined with the Missile Defense Agency (MDA) Hypersonic and Ballistic Tracking Space Sensor (HBTSS) Medium Field of View (MFOV) SVs that provide precision global access capability. This set of contract awards will initiate the development of the first eight low-cost proliferated WFOV SVs..."

After Class: Working with Phase-Shift Oscillators

After Class: Working with Phase-Shift Oscillators, December 1958 Popular Electronics - RFCafeThere is an old adage that goes thusly: "If you want to build an oscillator, design an amplifier. If you want to build an amplifier, design an oscillator." Its basis is the difficulty that can be experienced in obtaining the right combination of feedback phase and amplitude. Of course experience, use of simulators, and careful circuit construction minimize the opportunity for validating that saying. The basic requirement for an oscillator is feedback from the output to the input that is in-phase and great enough in amplitude to maintain, via the amplifier's gain factor, a constant output level. Tuned L-C (inductor-capacitor) tank circuits are often used as simple frequency-determining elements because of their combined resonance characteristics. Phase shift oscillators are a type of oscillator that can be built without inductors...

Teledyne e2v HiRel and Silicon Labs Partner on Isolation

Teledyne e2v HiRel and Silicon Labs Partner on High Reliability Isolation - RF CafeSilicon Labs, a leading provider of silicon, software and solutions, today announced a new high reliability (HiRel) isolation partnership with Teledyne e2v HiRel, a leading provider of high-performance, high-reliability semiconductors to the aerospace and defense market. Under the new agreement, Teledyne will offer a new specialized line of high reliability products based on Silicon Labs' isolated gate driver technology optimized for space, aerospace, military and oil and gas markets. Teledyne e2v HiRel will market custom high reliability solutions based on Silicon Labs' Si827x isolated gate driver family that are optimized for space, aerospace, military, oil and gas and other markets requiring advanced technology and high reliability...

Many Thanks to Anatech Electronics for Long-Time Support!

Anatech Electronics logo - RF CafeAnatech Electronics (AEI) manufactures and supplies RF and microwave filters for military and commercial communication systems, providing standard LP, HP, BP, BS, notch, diplexer, and custom RF filters, and RF products. Standard RF filter and cable assembly products are published in our website database for ease of procurement. Custom RF filters designs are used when a standard cannot be found, or the requirements dictate a custom approach for your military and commercial communications needs. Sam Benzacar's monthly newsletters address contemporary wireless subjects. Please visit Anatech today to see how they can help your project succeed. 

Wednesday 21

Weather Detection Radar

Weather Detection Radar, October 1955 Radio & Television News - RF CafeRCA (Radio Corporation of America) is not really the first company name that comes to mind when thinking about radar, be it weather, aircraft navigation, or nautical navigation. Instead, I think of radios and televisions and even satellites; RCA developed the circa 1958 SCORE series. According to this 1955 article in Radio & Television News magazine, RCA designed and built a a C-band airborne radar system for detecting adverse weather conditions enroute, at a range of up to 150 miles. Operating at around 5.4 GHz at 75 kW peak, the AVQ-10 radar unit was primarily meant for weather avoidance rather than for terrain and aircraft avoidance. The installed weight of 125 pounds was rather amazing considering the use of vacuum tubes and a CRT display (also a vacuum tube), along with leaded passive components and bulky, heavy (relatively) transformers for providing high voltage...

PCBONLINE Blog: How to Create a Custom PCBA

PCBONLINE Blog: How to Create a Custom PCBA - RF CafePCBONLINE, a one-stop custom PCB/PCBA manufacturer for prototypes, small-batch, and massive production, recently published a technical blog to explain how to create a custom PCBA. It answers what is a PCBA, how to create a custom PCBA, the techniques used for manufacturing the PCBA, etc. When a PCB is mounted with electronic components, it becomes a PCBA (printed circuit board assembly), which is a semi-finished electronic product that achieves the vital function of an electronic device. PCBAs are used in almost all electronics industries. PCBAs manufactured by PCBONLINE include the high frequency PCBA, multilayer PCBA, rigid-flex PCBA, aluminum PCBA, etc. 1 to 100 layer PCBAs can be delivered in 3 days...

Printing High-Speed Low-Power Organic Transistors

Printing High-Speed Low-Power Organic Transistors - RF Cafe "For around 10 years, smartphones and computer screens have been based on a display technology composed of so-called thin film transistors. These are inorganic transistors that require very little power, and they have proven themselves capable, given their widespread adoption. But they have limits that researchers have been busy trying to overcome. 'We explore new ways to improve upon thin film transistors, such as new designs or new methods of manufacture,' said Gyo Kitahara, a Ph.D. student from the Department of Applied Physics. 'Organic thin film transistors, for example, have a bright future in LCD screen devices. Compared to the inorganic kind currently used..."

RCA Victor Advertisement from The Saturday Evening Post c1948

RCA Victor Advertisement from the November 6, 1948, The Saturday Evening Post - RF CafeHere is an advertisement by RCA Victor (Radio Corporation of America) from the November 6, 1948, edition of the The Saturday Evening Post. As was common in the day, the company specifically addresses Americans in an American magazine. Rarely anymore does a major American company use the word "America" or "American" in promotional material because of globalism and the fear of being too committed to the well-being of its native country. The same is true of most western countries' corporations, where their country names can be substituted for "America" in this piece. Up through about the 1980s it was commonplace to specifically address countrymen. Once manufacturers ramped up offshoring efforts the practice began disappearing. Offshoring is distinctly different from importing another...

ConductRF Low Smoke / Zero Halogen Cable Solutions

ConductRF Low Smoke/Zero Halogen Cable Solutions - RF CafeConductRF is pleased to offer Low Smoke / Zero Halogen Jacketed RF Cables for various applications Indoor and Outdoor for Naval Ship-Board applications. We have two ranges of solutions aimed at differing RF requirements with our SBA series aimed at Higher Frequency 18 GHz needs. These are 100% factory tested to exacting VSWR and Loss standards because, We know, Results Count! ConductRF manufactures a range RF Cables in support of Ship Board applications, where Low Smoke, Zero Halogen requirements are mandated. These cable have Low Smoke Polyolefin Jackets that are suitable for Ship Board Environments. The Cable solutions are commonly available in 3 sizes with cable OD of 0.240", 0.405" and 0.590"...

Thanks to PCB Directory for Continued Support!

PCB  Directory - RF CafePCB Directory is the largest directory of Printed Circuit Board (PCB) 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.

Tuesday 20

For the Record: Scatter Communications

For the Record: Scatter Communications, October 1955 Radio & Television News - RF CafeIt seems Amateur radio operators in every country have perpetually been in a battle against government bureaucrats. Early on, Hams were allocated small segments of available "usable" spectrum and a fairly wide swath of the less desirable spectrum. That was especially true of the microwave bands when there was not a lot of components and equipment available that could operate at the higher frequencies. Those familiar with history are familiar with the situation where Amateurs developed a lot of the technology for operating in the upper MHz and into the GHz realm, and then the government snatched it from them for commercial and military use. Hams pretty much pioneered atmospheric scatter as a means for long distance (DX), over-the-horizon communications using those upper frequencies. This editorial from a 1955 issue of Radio & Television News magazine reports on a relatively newer variation dubbed "forward-scatter," which works in 40-80 MHz band (6-meters and VHF) when the transmitted power is sufficiently high. The military, which discovered the phenomenon and had recently declassified it, was considering allowing Amateurs...

Quietest Semiconductor Quantum Bits on Record

Quietest Semiconductor Quantum Bits on Record - RF Cafe"Researchers at UNSW Sydney have demonstrated the lowest noise level on record for a semiconductor quantum bit, or qubit. The research was published in Advanced Materials. For quantum computers to perform useful calculations, quantum information must be close to 100 percent accurate. Charge noise - caused by imperfections in the material environment that hosts qubits - interferes with quantum information encoded on qubits, impacting the accuracy of the information. "The level of charge noise in semiconductor qubits has been a critical obstacle to achieving the accuracy levels we need for large-scale error-corrected quantum computers," says lead author Ludwik Kranz, a Ph.D. student at UNSW's Centre for Quantum Computation and Communication Technology (CQC2T) working with the Centre's spin off company Silicon Quantum Computing (SQC)..."

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!

Electronic Menu Quiz

Electronic Menu Quiz, August 1963 Popular Electronics - RF CafeThis Electronic Menu Quiz appeared in the August 1963 edition of Popular Electronics magazine. Robert Balin created many such quizzes for Popular Electronics over the years. It challenges you to match the common food-related term for a device with its picture. If you've been around electronics labs and/or read electronics hobbyist magazines for a while, chances are you have run across most of the terms. I suggest you click on the image to get a full-size view of the drawings to be able to see all the detail. A couple of the names I have to admit not being familiar, so they seem rather 'corny'... get it?

Military Mast Problems and Solutions

Military Mast Problems and Solutions - RF CafeEach month the ARRL's flagship magazine, QST, makes an article available for free to non-members. November's selection is entitled "Military Mast Problems and Solutions." Bob Dixon, W8ERD, begins: "Many of us use military surplus masts and tripods to hold up antennas, especially in portable situations. They work very well, but these masts have potential stability problems, because the adjacent mast sections and tripod are held together by their weight and by friction alone. If the mast is tilted by the wind or pulled by a wire, the mast joints and tripod can separate, and the entire structure can fall down catastrophically. Also, if you have a rotatable antenna on the mast, the mast sections can slip and rotate the antenna, or make it difficult to turn. These problems can be fixed by pinning all the mast sections and the tripod together..."

Skyworks Circulator for Radar Systems and Wireless Apps

Skyworks Surface Mount Circulator for Radar Systems and Wireless Applications - RF CafeSkyworks is pleased to introduce the SKYFR-001982, a small form factor surface mount circulator for L-Band radar systems and wireless applications in the 1200-1400 MHz operating range. This device offers high power level handling with minimal thermal rise, providing a flow path for the RF signal as well as protection for sensitive components from excess signal reflection. Packaged in a compact SMT housing, the SKYFR-001982 can be easily incorporated onto PCB boards with automated pick and place manufacturing. The SKYFR-001982 is the latest in Skyworks' broad portfolio of Circulator and Isolator products for radars for both military and commercial applications...

Thanks to TotalTemp Technologies for Continued Support!

TotalTemp Technologies - RF CafeTotalTemp Technologies has more than 40 years of combined experience providing thermal platforms. Thermal Platforms are available to provide temperatures between −100°C and +200°C for cryogenic cooling, recirculating circulating coolers, temperature chambers and temperature controllers, thermal range safety controllers, space simulation chambers, hybrid benchtop chambers, custom systems and platforms. Manual and automated configurations for laboratory and production environments. Please contact TotalTemp Technologies today to learn how they can help your project.

Monday 19

Synkote Wire & Cable

Synkote Wire & Cable, November 1953 Radio-Electronics - RF CafeI'm always tempted to wax nostalgic over ads like this one since they remind me of more care-free childhood and early teenage years when our household had the typical single television set with an antenna on the roof and a 300 Ω twin lead cable running haphazardly down the roof surface and over the metal gutter, stretching under the eave to where it was crushed between the window sill and lower window pane, and snaked along the wall and floor to the TV. In the early days, our antenna was fixed (no rotator). Situated in Mayo, Maryland, about midway between Baltimore and Washington, D.C., where our nearest broadcast stations resided, we somehow managed to get acceptable reception on our low-end black & white television. I don't recall in which direction the antenna was pointed (maybe northwestish to cover both directions equally). It wasn't until sometime in the early 1970s that we finally got our first color TV that the system showed its weakness...

Military Renaissance in High Frequency Communications

Military Renaissance in High Frequency Communications - RF Cafe"Special operations commands across Europe are ramping up their capabilities with high-frequency communications to ensure connectivity on the battlefield. Leaders there are turning to high frequency communications as a way to optimize properties that provide a low probability of interception and detection. Special forces in France, Germany, Poland and Ukraine continue to receive high-frequency, or HF, systems as a way to diversify communications plans, industry sources confirmed to C4ISRNET. Some special operations organizations have selected L3Harris' AN/PRC-160(V), industry sources said. Enhancements in HF come at a time when NATO members and partner forces..."

Mathematical Puzzles, 1974 Old Farmer's Almanac

Mathematical Puzzles, 1974 Old Farmer's Almanac - RF CafeAs mentioned in an earlier post, a while back I bought a box full of vintage Old Farmer's Almanacs (OFA) at a yard sale, figuring there would be a bunch of good items to post here on RF Cafe and on my Airplanes and Rockets hobby website. Chief amongst the postworthy features is the Mathematical Puzzles section. They are a fair challenge to an engineer's cerebration, contemplation, and deliberation. These particular mathematical posers appeared in the 1974 issue of OFA. #10, while rated a difficulty of 4 (where 5 is most difficult), is really not even a mathematical challenge when you think about it (hint - it's an old riddle you've probably seen before). Enjoy!

A Self-Contained Handie-Talkie

A Self-Contained Handie-Talkie, June 1944 QST - RF Cafe"Handie-Talkie" was the name given to early walkie-talkies used in the field by military communications troops. Having been written during World War II, the author of this QST article just assumed that any reader would be familiar with the WERS acronym - it stands for War Emergency Radio Service. Per the Wikipedia entry: "At the start of the Second World War the United States Congress had suspended all amateur radio activity throughout the country. WERS was established by the Federal Communications Commission in June 1942 at the insistence of the American Radio Relay League. WERS would remain in operation in through the end of the Second World War in 1945. WERS was to provide communications in connection with air raid protection, and communications during times of natural disaster. WERS licenses were given to communities and not individuals...

Many Thanks to Anatech Electronics for Long-Time Support!

Anatech Electronics logo - RF CafeAnatech Electronics (AEI) manufactures and supplies RF and microwave filters for military and commercial communication systems, providing standard LP, HP, BP, BS, notch, diplexer, and custom RF filters, and RF products. Standard RF filter and cable assembly products are published in our website database for ease of procurement. Custom RF filters designs are used when a standard cannot be found, or the requirements dictate a custom approach for your military and commercial communications needs. Sam Benzacar's monthly newsletters address contemporary wireless subjects. Please visit Anatech today to see how they can help your project succeed. 

AARRL Lightning Calculator Type B Modified

ARRL Lightning Calculator Type B Modified, front (Joseph Birsa) - RF CafeThis is not something devised by Benjamin Franklin. Rather, the American Radio Relay League (ARRL) sold a variety of these "Lightning Calculator" slide rules in the days before electronic calculators. This "Type B" version (copyright 1932, W.P. Koechel) calculates Ohm's Laws values for resistance, voltage, current, and power. As shown here, it indicates an alignment of 1 V, 1 A, and 1 Ω. The Lightning Calculators" were rather large at 8½" wide by 11" high. Being the size of a sheet of paper, it is surprising they did not come with holes for a 3-ring binder. There were six varieties of "Lightning Calculators," as shown in the 1939 QST magazine advertisement. Thanks to Joe Birsa (N3TTE) for the donation.

Please Check in Appreciation of Their Support

Empower RF Systems - RF CafeEmpower RF Systems is a global leader in power amplifier solutions. Empower RF Systems is an established and technologically superior supplier of high power solid state RF & microwave amplifiers. Our offerings include modules, intelligent rack-mount amplifiers, and multi-function RF Power Amplifier solutions to 6 GHz in broadband and band specific designs. Output power combinations range from tens of watts to multi-kilowatts. Unprecedented size, weight and power reduction of our amplifiers is superior to anything in the market at similar frequencies and power levels.

Sunday 18

Science & Engineering Themed Crossword Puzzle for October 18th

Science & Engineering Themed Crossword Puzzle for October 18th, 2020 - RF CafeOctober 18th's custom Science and Engineering Technology themed crossword puzzle contains only only words from my custom-created lexicon related to engineering, science, mathematics, chemistry, physics, astronomy, etc. (1,000s of them). You will never find among the words names of politicians, mountain ranges, exotic foods or plants, movie stars, or anything of the sort. You might, however, find someone or something in the otherwise excluded list directly related to this puzzle's technology theme, such as Hedy Lamarr or the Bikini Atoll, respectively. The technically inclined cruciverbalists amongst us will appreciate the effort.

Friday 15

OSCARs Help Dedicate New Air and Space Museum

OSCARs Help Dedicate New Air and Space Museum, September 1976 QST - RF CafeThat would be President Ford in the background atop the platform, behind where the OSCAR ground station was set up. He was there as part of the dedication of the new National Air & Space Museum in Washington, D.C., in 1976. The event was part of the nationwide series of bicentennial celebrations marking America's founding with the signing of the The unanimous Declaration of the thirteen united States of America. Apollo 11 astronaut Michael Collins directed the event. The Space Race was in its heyday and most people were still in awe of anything related to spacecraft - both manned and unmanned. Just about anyone other than a Ham radio operator believed communicating with a satellite was the exclusive domain of governments, so the presence of AMSAT...

Memristor Acts Like a Neuron

Memristor Acts Like a Neuron - RF Cafe"Analog computing with neuron-like devices could efficiently solve problems traditional computers struggle with. One thing that's kept engineers from copying the brain's power efficiency and quirky computational skill is the lack of an electronic device that can, all on its own, act like a neuron. It would take a special kind of device to do that, one whose behavior is more complex than any yet created. Suhas Kumar of Hewlett Packard Laboratories, R. Stanley Williams now at Texas A&M, and the late Stanford student Ziwen Wang have invented a device that meets those requirements. On its own, using a simple DC voltage as the input, the device outputs not just simple spikes, as some other devices..."

Ionosphere and Radio Transmission

The Ionosphere and Radio Transmission, March 1940 QST - RF CafeReading through this article reminds me of studying for the amateur radio exams. In fact, the information presented in this 1940 QST piece does not seem to be lacking anything that contemporary discussions include. My point is that a great amount of knowledge had already been amassed about earth's upper atmosphere a mere four decades after the first transatlantic radio communications were accomplished by Marconi on December 12, 1901 from Poldhu in Cornwall, England, to Newfoundland, Canada. Considering that at the time no instrumented sounding rockets had been launched into the extreme upper layers (F1 & F2, beginning at around 120 mi | 200 km), a lot had been discerned about characteristics as they pertain to radio communications. Balloons were used for direct measurements...

Review of the 2020 Virtual IMS (vIMS)

Review of the 2020 Virtual IMS (vIMS) - RF CafeIn his latest The Accidental Engineer blog post, Reactel's Jim Assurian offers his assessment of the first-ever Virtual IMS (vIMS), made necessary by the COVID-19 worldwide epidemic this year compliments of Wuhan, China. Jim begins: "Some contemplative reactions to the Virtual IMS from an Exhibitor - the comments are my own and may not be indicative of other's experience or their impression of the vIMS. The live portion of the Virtual IMS concluded on August 6th though much of the Conference is available On-Demand thru September 30th. I encourage you to visit the Conference website. If I had to rate my experience with the vIMS on a scale of 1 thru 5, I'd give it a 1. I was underwhelmed by the interface as I noted in my earlier blog post, and the 'traffic' through my booth was minimal at best. Once I subtracted out the industry friends who swung past for a look..."

Free Engineering White Papers & Books

Engineering White Papers & Books, October 2020 - RF CafeReading trade journals is always given as one of the main ways cited by engineers on career surveys for continuing education. Engineering whitepapers, pamphlets, books, magazines, and chapter examples listed here are a small sample of a lot of new items that are offered for FREE through TradePub. The publishers make them available to qualifying people as a promotional campaign for their full line of offerings. Whitepaper topics include careers, manufacturing, and engineering, while magazine titles include NASA Tech Briefs, Electronic Component News, and Microwave Product Digest. Note: I earn a few pennies (literally) when you download one of these or the many other pubs available, so please help yourself.

Please Visit Res-Net Microwave in Appreciation of Support!

Res-Net Microwave Components - RF CafeRes-Net Microwave has a complete line of precision RF & microwave components including attenuators, terminations, resistors, and diode detectors for commercial, military, and space applications. Products range from the small flange type to large 2,000 watt connectorized power attenuators and/or terminations at frequencies up to 26.5 GHz. In-house photo etch and laser trim capability. The company is a leader in development and production of the films required for these type of RF/microwave components. Please check out Res-Net Microwave's website to see how they can help with your current project.

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