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Homepage Archive - May 2022 (page 1)

See Page 1 | 2 | 3 | 4 | 5 of the May 2022 homepage archives.


Friday the 6th

United Screw and Bolt Corporation Clutch Head Screws

United Screw and Bolt Corporation Clutch Head Screws, October 1946 Radio News Article - RF CafeI have always wondered why hex (Allen) or clutch type heads for everyday wood, metal, and plastic screws and machine screws (aka small bolts) was not the norm rather than Phillips heads. Phillips heads are fine when the screws are not hard to get out, but when they are really difficult to break loose, a lot of force toward the screw is often required whilst turning. Unless you have a prefect fit between the driver and the screw head, the driver tends to ride up out of the cross slot. A straight slot screwdriver does not usually have that issue, but it has the disadvantage of slipping out of the screw slot and damaging the item it is holding (or your hand). Hex head, Torx head, clutch head, and other types with vertical walls also do not require a lot of inward force when really cranking on them. Maybe it's just me. This 1946 Radio News magazine promotion by the United Screw and Bolt Company extolls the virtues of their clutch head design. The point about restoring the damaged end of clutch head driver back to its original condition by putting it to a grinder...

Qualcomm Lays out Path to 6G

Qualcomm's John Smee Lays out Path to 6G - RF Cafe"Speaking at this week's Brooklyn 6G Summit, Qualcomm's SVP of Engineering John Smee took a bird's-eye view at the 5G landscape and the evolution to 6G. He noted that 5G standardization work began with Release 15 and has now progressed through Release 16 and 17, which just finished. Release 17 moved into new technologies, such as non-terrestrial networks and the introduction of New Radio Reduced Capability (NR-RedCap) for the internet of things (IoT). NR-RedCap only needs 10 MHz bandwidth to achieve a data rate of 150 Mbps and can reduce the power consumption of IoT devices. It is expected to be adopted in places where power supply is unavailable and high-speed transmission is required. Smee considers the next phase with Releases 18, 19 and 20 as the '5G Advanced' era, culminating in 6G around the year 2030..."

Blog: Shed Some Light on Solar Power Testing

Axiom Test Equipment Blog: Shed Some Light on Solar Power Testing - RF CafeAxiom Test Equipment, Inc., an electronic test equipment rental and sales company has published a new blog post on Solar Power testing. PV technology is gaining wider acceptance, as it is providing electricity for everything from wearable medical devices to large manufacturing facilities. In this post we explain how with the right power supplies for simulation and well-equipped analyzers for investigation, a future with solar power sources such as PV cells, modules, and arrays is closer than we think. Test equipment for PV cells, modules, panels, and arrays should be capable of performing the types of measurements that typically characterize such PV components and systems, including short-circuit current testing and open-circuit voltage testing, Additional PV measurement capabilities include solar responsivity or how a PV device responds to different wavelengths of light and how efficiently it can convert light to electricity. Useful test equipment capabilities include wide I and V measurement ranges, high AC and DC power accuracy, and high resolution. For controlling DC power levels at various points along a PV system...

Make Extra Profits Changing Push-Button Radios to New Frequencies

Make Extra Profits Changing Push-Button Radios to New Frequencies, June July 1940 National Radio News - RF CafeThe old pushbutton radio tuners were an ingenuous bit of electromechanical wizardry. For those too young to have experienced them, operation was simple - turn the radio tuning knob to your broadcast station, pull out the lever/button, and then push it all the way back in. Done. The next time you pushed that button, the mechanism would slew the dial indicator to that position, taking the tuning elements (usually just a variable capacitor) with it. For most modern electronic radios, you program the station button by pushing and holding it for a few seconds until a beep is heard. My father never quite got the hang of tuning the pushbutton radio in his old Rambler (vacuum tubes) or even his 1978 Chevy pickup truck (transistorized, but with mechanical tuner). He was never an early - or late for that matter - adopter of new technology, so it was not surprising. I am surprised, though, at the number of times I have had to show a Millennial type how to program his/her late model car radio...

How Green Is Your eCar's LiPo Battery?

How Green Is Your eCar's LiPo Battery? - RF CafeYou really need to see these photos if you do not know where and how most of the lithium for LiPo batteries originates. I have written in the past about the environmental and human destruction done in the pursuit of "green" goals. The end result is used to justify the means - a truly deceptive tactic. The images in this story are from a more public relations friendly source, but others can be found showing local natives wading through the brine pools with rakes and squeegees, wearing minimum protective gear. Chile's high and dry Atacama Desert (also home to the Extremely Large Telescope) is thought to contain about 40% of the world's lithium and much copper.

Channel Master Yagi Antenna Ad

Channel Master Yagi Antenna Ad, October 1951 Radio & Television News - RF CafeIn Spring of 2018, I installed an old-fashioned (but newly manufactured) Channel Master CM3020 Advantage 100 television antenna on a short tower (maybe just a pole) with a vintage Alliance Model U-100 Tenna-Rotor. While living in Erie, Pennsylvania, under certain conditions I could receive broadcasts from Erie and many of the cities that border close to Lake Erie like Toronto and Waterloo (home of Blackberry), Canada and even Detroit, Michigan. AM radio stations are easily pulled in from the same areas, but FM does not do quite so well. I plan to also integrate some form of FM antenna on the installation. There is something insulting about paying for cable or satellite TV and then having to suffer the deluge of commercials as well (I have neither). Nobody likes sitting through commercials, but at least if the programming is being delivered at no cost, it is not unreasonable for the broadcast companies to be paid by product sponsors...

RF & Electronics Symbols for Office™

RF & Electronics Schematic & Block Diagram Symbols for Office™ r2 - RF CafeIt was a lot of work, but I finally finished a version of the "RF & Electronics Schematic & Block Diagram Symbols" that works well with Microsoft Office™ programs Word™, Excel™, and Power Point™. This is an equivalent of the extensive set of amplifier, mixer, filter, switch, connector, waveguide, digital, analog, antenna, and other commonly used symbols for system block diagrams and schematics created for Visio™. Each of the 1,000 or so symbols was exported individually from Visio in the EMF file format, then imported into Word on a Drawing Canvas. The EMF format allows an image to be scaled up or down without becoming pixelated, so all the shapes can be resized in a document and still look good. The imported symbols can also be UnGrouped into their original constituent parts for editing. Check them out!

Many Thanks to KR Electronics for Long-Time Support!

KR ElectronicsKR Electronics designs and manufactures high quality filters for both the commercial and military markets. KR Electronics' line of filters includes lowpass, highpass, bandpass, bandstop and individually synthesized filters for special applications - both commercial and military. State of the art computer synthesis, analysis and test methods are used to meet the most challenging specifications. All common connector types and package form factors are available. Please visit their website today to see how they might be of assistance. Products are designed and manufactured in the USA.

Thursday the 5th

Electronics-Themed Comics

Electronics-Themed Comics, October 1950 Radio & Televsion News - RF CafeHere are a couple more electronics-themed comics from you that appeared in the October 1950 issue of Radio & Television News magazine. The comic on page 50 might challenger your ability to appreciate the situation. Television was still a relatively new phenomenon and people were fanatical (the origin of "fan" is "fanatic") over it. Crowds gathered in front of store windows containing a TV set to watch the magic of the technology. The opportunity to watch live sporting events via television was available to many people only at venues outside the home, as a TV was still a middle class accessory at the time. Today when people gather around a TV set at a bar, it is not because they could not watch it on their smartphones or home TV sets or computers, but because they want the camaraderie of fellow fans. Although I am tempted to assume most people "get" the gag in the page 167 comic, it could very well be that not many are familiar with what a radio or TV antenna looks like, since the ones they use are buried inside their phones. It is rare to see an old-fashioned multi-element antenna on a house anymore, and the antennas on cell towers look nothing like them. About the only place you see...

Strange Metal Magic-Angle Twisted Bilayer Graphene

Strange Metal Behavior in Magic-Angle Twisted Bilayer Graphene - RF Cafe"Magic-angle twisted bilayer graphene (MATBG) is a graphene-based material with a unique structure, consisting of two graphene sheets layered on top of each other with a misalignment of approximately 1.1°. This unique structure has been found to host various interesting states, including correlated insulating states and unconventional superconductivity. Past studies examining MATBG also unveiled the emergence of what is known as a 'strange' metal regime in the proximity of the superconducting dome, as well as a significantly enhanced electron-phonon coupling. While these observations were confirmed by later works, the exact mechanisms underpinning them remain unclear. Researchers at the Barcelona Institute of Science and Technology, the National Institute for Material Sciences, and Massachusetts Institute of Technology (MIT) have recently taken a closer look at these properties of MATBG using a different, low temperature phase diagram than those utilized in previous works..."

Did J.J. Thomson Discover the Electron?

Did J.J. Thomson Discover the Electron? - RF CafeLong-held beliefs about just about every subject are constantly being challenged by people who discover evidence that another "truth" might be more valid. Bell's telephone vs. Gray, the Wright Brother's airplane vs. Langley and Whitehead, etc. These days, it is great sport to attempt to discredit someone of significant achievement. This article appeared on the IEEE Spectrum website and questions whether J.J. Thompson actually discovered the electron (aka the corpuscle). It begins: "'We shall call such particles corpuscles,' announced the physicist J.J. Thomson, during a lecture at the Royal Institution in London, on 30 April 1897. 'The atoms of the ordinary elements are made up of corpuscles and holes, the holes being predominant,' he continued. Thomson described his experiments with cathode rays to verify the existence of these subatomic corpuscles. This model of the atom became known as the 'plum pudding' model, so named for the popular English dessert. In Thomson's analogy, negatively charged corpuscles were like raisins suspended in a positively charged cake, resulting in a neutral atom. The model also became known as the Thomson model, although its chief proponent was William Thomson (Lord Kelvin), not J.J. Thomson, who merely endorsed the idea..."

"Printed Wiring" Techniques for the Experimenter

"Printed Wiring" Techniques for the Experimenter (Part 2), September 1956 Popular Electronics - RF CafeHere is the second of a 2-part article introducing hobbyists to the relatively new technique of printed circuit board (PCB) or, alternately, printed wiring board (PWB) fabrication. Author Louis Garner is from Bell Telephone Labs, which was an early adopter of PWBs. Bell had millions of relay switch and controller circuit boards for routing all the country's telephone calls. I remember a couple times in high school while working as an electrician's helper where we did some wiring inside a phone switching station and saw row upon row of racks of identical panels full of relays. They were clacking busily away in an almost deafening cacophony of non-synchronized noise. It was pretty cool at first, but after an hour or so the novelty wore off and it became annoying. Today, probably all you would hear in a telephone switching station is the sound of cooling fans keeping all the ICs and hard drives within temperature specs...

Antenova "Lama" Antenna for 868 &  915 MHz Networks

Antenova's "Lama" Antenna for EU 868 MHz and U.S. 915 MHz Networks - RF CafeAntenova Ltd, the UK-based manufacturer of antennas and RF antenna modules for M2M and the IoT, launches a new low-profile antenna displaying strong performance on both Europe's 868 MHz bands and the U.S. 915 MHz bands. The new antenna is named "Lama," part number SRFI065. It was developed for small connected devices operating on the LP-WAN networks including LoRa, Sigfox, Wi-SUN and MIoTy. This antenna uses the ISM frequencies in Europe and America or both, which means that one product design can be sold in both US and European markets. Lama is a particularly small antenna, making it suited to designs with limited real estate. It is a flexible printed circuit (FPC) antenna measuring 35 x 10 x 0.15 mm, supplied with a standard 100 mm RF cable with I-PEX MHF connector. This shape allows it to be mounted several different ways in a design...

RF & Electronics Stencils for Visio

RF & Electronics stencils for Visio r4 - RF CafeWith more than 1000 custom-built stencils, this has got to be the most comprehensive set of Visio Stencils available for RF, analog, and digital system and schematic drawings! Every stencil symbol has been built to fit proportionally on the included A-, B-, and C-size drawing page templates (or use your own page if preferred). Components are provided for system block diagrams, conceptual drawings, schematics, test equipment, racks (EIA 19", ETSI 21"), and more. Test equipment and racks are built at a 1:1 scale so that measurements can be made directly using Visio built-in dimensioning objects. Page templates are provided with a preset scale (changeable) for a good presentation that can incorporate all provided symbols...

Many Thanks to ISOTEC for Continued Support!

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

Wednesday the 4th

Practical Radar (part 2)

Practical Radar (part 2), July 1945 Radio News - RF CafeHere is Part 2 of a multi-part article on radar that was published in Radio News magazine in 1945. Part 1 appeared a month earlier, and the series ran into the Fall. In the interim, World War II was won and ended by the Allies. Interestingly, a lot of readers wrote in to the magazine to criticize the divulging of sensitive technical information on one of the era's most significant developments. Other than being able to generate quality RF and analog signals (no digitization at this point), the most critical subsystem of a radar is timing. Without precision accounting of the times of transmission and reception, and of processing of the information for displaying to the radar operator, the system is worse than useless. Improper timing will cause confusion over where the detected target is in both azimuth and range. Positioning your defense to counter an attack thought to be 10 miles out and due east, when it is actually 2 miles away an approaching from the north could prove devastating. In fact, one type of radar countermeasure attempts to create just that scenario...

Zero-Index Metamaterial Quantum Mechanics

Zero-Index Metamaterial Quantum Mechanics - RF Cafe"In physics, as in life, it's always good to look at things from different perspectives. Since the beginning of quantum physics, how light moves and interacts with matter around it has mostly been described and understood mathematically through the lens of its energy. In 1900, Max Planck used energy to explain how light is emitted by heated objects, a seminal study in the foundation of quantum mechanics. In 1905, Albert Einstein used energy when he introduced the concept of photon. But light has another equally important quality, known as momentum. And as it turns out, when you take momentum away, light starts behaving in really interesting ways. An international team of physicists led by Michaël Lobet and Eric Mazur, at the Harvard John A. Paulson School of Engineering and Applied Sciences (SEAS), are re-examining the foundations of quantum physics from the perspective of momentum and exploring what happens when the momentum of light is reduced to zero..."

Networks for Television

Networks for Television, November 1947 Radio News - RF CafeNationwide commercial television broadcasting companies wasted no time stringing coaxial cable and microwave towers from sea to shining sea once the NTSC format standard was adopted and manufacturers had spooled up production after World War II. Adoption of cable services was slow because a fee was involved, but once purely cable channels started being added the perceived value increase convinced consumers to open their wallets. Eventually cable eclipsed over-the-air broadcasts for all but extremely rural areas that were not serviced by cable. Along came satellite TV to take care of filling that void. Once a small, inexpensive, unobtrusive Ka-band antenna replaced the huge S-band backyard parabolic dishes and subscription prices dropped significantly, suburbanites and city dwellers picked it up. Soon, cable companies were feeling the pinch as their customer bases shrunk. Not ones to sit and take the loss, "cable" exploited the rapidly falling landline subscriber base due to cellular service by pushing VoIP via cable to the point where in some areas you cannot even get legacy twisted

R&S Hunter Class Frigate Communication Systems Integrator

Rohde & Schwarz on Board as Hunter Class Frigate Communication Systems Integrator - RF CafeRohde & Schwarz Australia will design and manufacture an integrated communications system (ICS) for the Royal Australian Navy (RAN) Hunter Class Frigate Program (HCFP), following signature of a contract with BAE Systems Australia's (BAESA) maritime division that allows for the addition of scopes of work over time. Under the initial scope of the early engineering contract, Rohde & Schwarz Australia will provide in country program management, systems engineering, integration, installation and verification services for the acquisition and introduction into service of the ICS. "The selection of Rohde & Schwarz Australia as Communications System Integrator (CSI) in this early phase of the Hunter program is a clear validation of the Commonwealth's and BAESA's intent to create opportunities for local industry participation...

Simple L and C Calculations

Simple L and C Calculations, September 1947 QST - RF CafeAlthough single capacitor, single inductor resonant tank circuits are not widely used these days, one place you do find them is in transistor amplifier stages in order to peak gain in a particular frequency band. In this 1947 QST article, Author Jack Najork offers a few pointers regarding the performing of quick mental calculations for how ranges of capacitance values affect the resonant frequency. For instance, the ratio of capacitance values needed to cover a certain range of resonant frequencies is equal (ideally) to the square root of the frequency ratio. This comes into play both when determining values during the design phase and the selecting of a variable capacitor for providing tuning over a continuous range of frequencies. The same is true for inductor selection, of course.  BTW, the capacitance unit of μμfd is the same as what we today term pF...

RF & Electronics Stencils for Visio

RF & Electronics stencils for Visio r4 - RF CafeWith more than 1000 custom-built stencils, this has got to be the most comprehensive set of Visio Stencils available for RF, analog, and digital system and schematic drawings! Every stencil symbol has been built to fit proportionally on the included A-, B-, and C-size drawing page templates (or use your own page if preferred). Components are provided for system block diagrams, conceptual drawings, schematics, test equipment, racks (EIA 19", ETSI 21"), and more. Test equipment and racks are built at a 1:1 scale so that measurements can be made directly using Visio built-in dimensioning objects. Page templates are provided with a preset scale (changeable) for a good presentation that can incorporate all provided symbols...

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.

Tuesday the 3rd

Bell Telephone Labs - Traveling Wave Tube

Bell Telephone Laboratories - Travelling Wave Tube, November 1957 Radio-Electronics - RF CafeContrary to the claim in this Bell Telephone Laboratories promotional piece from a 1957 issue of Radio-Electronics magazine, according to the Wikipedia entry for the traveling wave tube (TWT) was invented in 1931 by Andrei "Andy" Haeff while he was working as a doctoral student at the Kellogg Radiation Laboratory at Caltech. His original patent, "Device for and Method of Controlling High Frequency Currents," was granted in 1936 (US2064469A). Bell gives credit to Dr. Rudolf Kompfner. The TWT's wide bandwidth, 500 MHz in this case - was heralded as a major breakthrough for supporting the rapidly growing microwave relay network spanning the country, vastly increasing the number of concurrent telephone connections. By that time (1957) transcontinental video broadcasts were also being made thanks to the system. It would still be half a decade before satellites (e.g., Telstar) would be available for long distance communications...

"This Is Ham Radio" ARRL Promotional Film

"This Is Ham Radio" ARRL Promotional Film - RF CafeThis promotional film (now an online video) entitled "This Is Ham Radio" was produced by the American Radio Relay League (ARRL) circa 1970. It shows the many aspects of amateur radio including building and operating transmitters and receivers, erecting antennas, and engaging in contests - in both fixed and mobile venues. At that time, entrance into the world of Ham radio was tougher than it is nowadays because proficiency at Morse code was required - a minimum of five words per minute sending and receiving. The entire pool of questions and answers was not readily available for studying for the written exam either, like it is today. For those who like to accuse organizations of ignoring and/or discouraging the participation of anyone other than White males, please note care was taken to include Blacks, Latinos, Asians, women and girls, youngsters and seniors. That was more than half a century ago. In fact, some of this footage is borrowed from an earlier ARRL film made in the 1960s and narrated by Senator Barry Goldwater (K7UGA), demonstrating an even longer-ago inclusionary effort. Since that time, many more resources have been invested...

Atomically Thin Electronics via Chemical Reactions

Atomically Thin Electronics vai Chemical Reactions - RF Cafe"There have been a variety of demonstrations of the capabilities that atomically thin materials can bring to electronics - extremely small size, excellent performance, and some distinctive properties. But almost all of these demonstrations required that the electronics being tested were essentially assembled by hand. Materials like graphene are often placed on a surface at random, and then the wiring needed for it to function is built around that location. It's not exactly a recipe for mass production. To the extent there's been some progress, it's been limited. One of the more recent efforts involved using graphene and molybdenum disulfide to make the transistor with the smallest gate length. In this case, the two atomically thin materials had to be placed carefully, but not exactly. Any excess material was etched away, and a key feature was made by cutting through the graphene sheet..."

Exodus AMP2073BDB-LC 0.7-10 GHz, 200 W SSPA

Exodus AMP2073BDB−LC 0.7-10 GHz, 200 W SSPA - RF CafeExodus Advanced Communications, a multinational RF communication equipment and engineering service company serving both commercial and government entities and their affiliates worldwide, announces their model AMP2073BDB-LC, a rugged compact dual-band 700 MHz to 10.0 GHz, solid state broadband amplifier. Class A/AB design for all applications and industry standards. This amplifier produces 200 W, 700 MHz to 6.0 GHz & 100W 6.0 to 10.0 GHz with 53 dB gain. Unprecedented performance as compared to TWT's with forward/reflected power monitoring in dBm & watts, VSWR, voltage/current/temperature sensing for extreme reliability. 30 kg's in a compact 5U chassis 8.75"H x 19"W x 27"D...

E-Waste... Just Don't Think About It

RF Cafe Video for Engineers - E-Waste... Just Don't Think About ItEvery once in a while someone upsets our comfortable existence by pointing out inconvenient realities like the problem of what happens to our electronics devices after the manufacturers convince us that we need the latest version of their wonder gadget. Unlike regular household recyclables like glass jars and cardboard cereal boxes, electronic devices contain a lot of valuable material that makes it profitable for reclamation if the work can be performed somewhere nobody really cares about the human costs of doing so. In China, India, Ghana, and many other "developing" countries, poor souls earn an existence by disassembling and performing crude processing of the components to separate heavy metals like gold, silver, lead, cadmium, beryllium, mercury, and others. For their efforts they sell their booty at a pauper's wage. After removing high value individual components like CPUs and RAM, as in these videos the rest is tossed into a fire to burn away the non-metals. If it is hot enough, the metals melt and drip onto a collection pan below. Wire is stripped of its insulation to yield only the copper or aluminum by burning off the plastic or rubber sheathing. The fumes from insulation often is toxic. Imagine inhaling that crap all day, every day. The level of pollutants leeching into the ground water supply and into the air are severe. From young to old, everyone participates. The U.S. Environmental Protection Agency masks the truth about what really happens to your exported e-waste..."

Practical Radar (part 5)

Practical Radar (part 5), October 1945 Radio News - RF CafeAfter having begun my electronics career in the USAF as an airport surveillance radar technician, my interest is always piqued by articles on the subject. Like so many other types of electronics, radar is so common today that not many people think it is anything special - just another convenience that has been around for as long as they can recall - and indeed it likely has been since radar was first put into practical operation in the early 1940s. In 1945, the last year of World War II, Radio News magazine ran a multi-month series on radar system theory of operation and design. When I look at the detailed block diagram, it brings back memories of the MPN-14 search and precision approach radar systems that I worked on. In tech school at Keesler AFB, Mississippi, we spent nine months for 7 hours per day, five days per week with piles of schematics learning stage by stage how the entire system worked. The primary radar systems, VHF, and UHF navigation radios were vacuum tube based, while the Identification Friend or Foe (IFF)...

RF Cascade Workbook

RF Cascade Workbook - RF Cafe RF Cascade Workbook 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 (click here for screen capture). 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 through the main features...

Please Thank IPP for Their Long-Time Support!

Innovative Power ProductsInnovative Power Products (IPP) has over 35 years of experience designing & manufacturing RF & microwave passive components. Their high power, broadband couplers, combiners, resistors, baluns, terminations and attenuators are fabricated using the latest materials and design tools available, resulting in unrivaled product performance. Applications in military, medical, industrial and commercial markets are serviced around the world. Products listed on website link to detailed mechanical drawings that contain electrical specifications as well as performance data. Please take a couple minutes to visit their website and see how IPP can help you today. 

Monday the 2nd

The Oscilloscope Applied to Transmitter Checking

The Oscilloscope Applied to Transmitter Checking, October 1945 Radio News - RF CafeBeing able to quickly interpret oscilloscope waveforms is essential to efficient circuit design, adjustment, and troubleshooting. Knowing tell-tale signatures of signal-corrupting influences from unintended resistance, capacitance, inductance, and nonlinear devices is a huge advantage when using an o-scope. Equally important is not introducing waveform- and function-altering effects with probing techniques and/or incorrect operation of the test equipment. One often seen example of the latter is using equipment whose input impedance is not proper for the UUT; e.g., wrong impedance coaxial cable in RF situations or too low of an input impedance for low frequency applications that either loads the circuit to the point of malfunction or where the voltage division is significant enough to cause improper readings on the display. Note the interesting comment at the beginning of this October 1945 Radio News magazine article regarding restoration of transmitting privileges for amateur radio operators at the end of WWII...

Transmissive Metasurface Redirects Cellular Signals

Transmissive Metasurface Redirects Cellular Signals - RF Cafe"Kyocera has developed a Transmissive Metasurface technology that can redirect wireless network signals in a specific direction to improve the coverage area and performance of 5G and eventually 6G networks. The Transmissive Metasurface will help deliver high-frequency millimeter-wave 5G and 6G to places where communication is impossible due to obstacles, expanding service areas beyond the capability of conventional Reflective Metasurface technologies used today. The 28 GHz band used in 5G networks, and the higher frequency band being studied for 6G, have a high degree of rectilinear propagation. Signals often cannot reach locations where a direct line of sight to the base station is obstructed..."

Newark Electric Company Ad

Newark Electric Company Ad, January 1946 Radio News - RF CafeWho among us has not ordered electronic components or hardware from Newark Electronics? Now known officially as "Newark element 14" (silicon?), and before that Newark Electronics, the company began life as Newark Electric Company, as shown in this 1946 advertisement that appeared in Radio-News. In the days before Digi-Key and the Internet, Newark and Allied were the standards for me when ordering stuff in the lab. Weekly long distance phone calls(remember when they were called that?) to Newark were the routine. Unless a project was really hot, standard U.S. Post Office delivery was used since at the time UPS and FedEx were deemed by the bean counters to be too exotic and expensive to justify the additional cost...

FCC Hiring Electronics Engineers

FCC Hiring Electronics Engineers - RF CafeFrom the ARRL website: "The Federal Communications Commission (FCC) has started accepting applications for electronics engineers for Recent Graduates positions in the Pathways Program which is located in the Office of Engineering and Technology in Washington, DC. Candidates should be recent graduates for this one year developmental program which may lead to a term or permanent appointment. Training will cover the agency's policy and rulemaking processes, technical training for a wide variety of telecommunications services and technologies, and training on engineering and policy principles relevant to the fast paced telecommunications industry. Additional duties, and related training, may also include performing propagation analysis of terrestrial, satellite..." One catch - you must get the jab.

Submarines - Are We Open to Sneak Attack?

Submarines - Are We Open to Sneak Attack?, February 1956 Popular Electronics - RF CafeSubmarines first proved their deadly capabilities during World War I and then again in World War II when Adolph Hitler's navy used the formidable U-Boats (Unterseeboot, "under-sea-boat") to torpedo not just military ships but merchant ships in commercial trade routes between the Americas and Europe. Hideki Tojo's navy used subs to conduct surveillance prior to the deadly surprise attack on Pearl Harbor. Their naturally stealthy environment - underwater - proved to be a difficult realm both for detection and for attack. Fortunately, sensor technology developed quickly during the war, and soon a combination of air and sea based methods were in use and proved very effective. Submariners no longer sailed in relative security from being treated to a violent, icy burial at sea. By the mid 1950s, when this article was published, we had detection capabilities that included direct visual, photographic, radar, sonar, and magnetic means...

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

Sponsor RF Cafe for as Little as $40 per Month - RF CafeNew Scheme rotates all Banners in all locations on the page! RF Cafe typically receives 8,000-15,000 website visits each weekday. RF Cafe is a favorite of engineers, technicians, hobbyists, and students all over the world. With more than 12,000 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.

Many Thanks to Bittele Electronics for Continued Support!

Bittele Electronics PCB Fabrication - RF CafeSince 2003, Bittele Electronics has consistently provided low-volume, electronic contract manufacturing (ECM) and turnkey PCB assembly services. It specializes in board level turnkey PCB assembly for design engineers needing low volume or prototype multi-layer printed circuit boards. Free Passive Components: Bittele Electronics is taking one further step in its commitment of offering the best service to clients of its PCB assembly business. Bittele is now offering common passive components to its clients FREE of Charge.

Sunday the 1st

RF & Microwaves Themed Crossword Puzzle for May 1st

RF & Microwaves Themed Crossword Puzzle for May 1st, 2022 - RF CafeHere is your custom made RF & Microwaves themed crossword puzzle for May 1st, 2022. All RF Cafe crossword puzzles are custom made by me, Kirt Blattenberger, and have only words and clues related to RF, microwave, and mm-wave engineering, optics, mathematics, chemistry, physics, and other technical subjects. 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., Reginald Denny or the Tunguska event in Siberia). The technically inclined cruciverbalists amongst us will appreciate the effort. Enjoy!

Get Your Custom-Designed RF Cafe Gear!

Custom-Designed RF-Themed Cups, T-Shirts, Mouse Pads, Clocks (Cafe Press) - RF CafeThis assortment of custom-designed themes by RF Cafe includes T-Shirts, Mouse Pads, Clocks, Tote Bags, Coffee Mugs and Steins, Purses, Sweatshirts, and Baseball Caps. Choose from amazingly clever "We Are the World's Matchmakers" Smith chart design or the "Engineer's Troubleshooting Flow Chart." My "Matchmaker's" design has been ripped off by other people and used on their products, so please be sure to purchase only official RF Cafe gear. My markup is only a paltry 50¢ per item - Cafe Press gets the rest of your purchase price. These would make excellent gifts for husbands, wives, kids, significant others, and for handing out at company events or as rewards for excellent service. It's a great way to help support RF Cafe. Thanks...

Many Thanks to LadyBug Technologies for Their Continued Support!

LadyBug Technologies RF Power Sensors - RF CafeLadyBug Technologies was founded in 2004 by two microwave engineers with a passion for quality microwave test instrumentation. Our employees offer many years experience in the design and manufacture of the worlds best vector network analyzers, spectrum analyzers, power meters and associated components. The management team has additional experience in optical power testing, military radar and a variety of programming environments including LabVIEW, VEE and other languages often used in programmatic systems. Extensive experience in a broad spectrum of demanding measurement applications. You can be assured that our Power Sensors are designed, built, tested and calibrated without compromise.

These archive pages are provided in order to make it easier for you to find items that you remember seeing on the RF Cafe homepage. Of course probably the easiest way to find anything on the website is to use the "Search RF Cafe" box at the top of every page. About RF Cafe.

Homepage Archive Pages

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LadyBug LB5954L Power Sensor with LAN Option - RF Cafe
Windfreak Technologies Frequency Synthesizers - RF Cafe

ConductRF Phased Matched RF Cables - RF Cafe

Cafe Press