Homepage Archive - August 2023 (page 4)

See Page 1 | 2 | 3 | 4 | of the August 2023 homepage archives.

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!

Thanks Again for Windfreak Technologies' Continued Support!

Windfreak TechnologiesWindfreak Technologies designs, manufactures, tests and sells high value USB powered and controlled radio frequency products such as RF signal generators, RF synthesizers, RF power detectors, mixers, up / downconverters. Since the conception of WFT, we have introduced products that have been purchased by a wide range of customers, from hobbyists to education facilities to government agencies. Worldwide customers include Europe, Australia, and Asia. Please contact Windfreak today to learn how they might help you with your current project.

Thursday the 31st

Electronics-Themed Comics

Electronics-Themed Comics, June 1961 Radio-Electronics - RF CafeHere are four electronics-themed comics that appeared in the June 1961 issue of Radio-Electronics magazine. The page 38 comic is also fitting for posting on my hobby website, AirplanesAndRockets.com, so it'll be put there soon. Comics showing television repairmen getting shocked by the high voltages while working inside the chassis was deemed great humor back when CRT (cathode ray tube) displays were used. Color TVs could easily have 20 kV or more on the tube. In the era of vacuum tubes, 300 volt cathode connections were the norm. In-home TV service calls often were the most stressful experiences of service shop employees, especially when the homeowner tried to tell the technician his business based on wild guesses, poorly researched data, or advice from friends. The page 101 comic is typical of such scenarios. The page 103 comic, on the other hand, is the kind of in-home service call servicemen looked forward to...

How Will 5G Advanced Change RF Design?

While reading through an article on the Design News website entitled "How Will 5G Advanced Change RF Design?," I saw a photo near the top of Qorvo's director of RF applications engineering, Jeff Gengler (left). Continuing down the page, the next picture I saw was that of Eric Westberg, director of product management at NXP Semiconductors. It caused me to scroll back up the page to be sure I wasn't seeing another photo of the same guy. The backgrounds in the two images were different, so it could have been Mr. Gengler in another setting, which might cause him to look a little different. Read the article to see what I mean. I took the liberty of superimposing Mr. Westberg's image on the same background as Mr. Gengler so you can see the two side-by-side. Maybe if you aspire to the position of head honcho in the design engineering department for a major RF semiconductor company, this could be a valuable lesson on ... something ;-)

Balanced Aerial System to Eliminate Interference

Using a Balanced Aerial System to Eliminate Interference, October 1932 Radio News - RF CafeQRM and QRN (manmade and natural interference, respectively) has been a problem to be dealt with since the beginning of radio communications. Amplitude modulation (AM) was and is still the most vulnerable because there are so many sources of electrical and electromagnetism generation - both intentional and unintentional. Filters can take care of out-of-band noise, but inband noise needs to be dealt with differently. Some inband interference can be reduced in effectiveness with circuits using specific time constants that address specific noise types. One of the most successful methods for mitigating generic noise is to limit the opportunity for noise signals to enter the system by employing directional antennas. Focusing (literally) reception in the direction of the preferred signal can cause other sources to be rejected. Reflecting surfaces like parabolic dishes and phased element antennas are the two basic choices. In some cases, as is the subject of this article, noise is picked up on the ground and lead-in wires of the antenna system. Constructing a balanced system will cause such interference to cancel before it ever reaches the receiver input...

Werbel 10 dB Directional Coupler for 6-18 GHz

Werbel Microwave Intros 10 dB Directional Coupler for 6-18 GHz - RF CafeWerbel Microwave model C−1806−10 from is a 10 dB directional power coupler 6 to 18 GHz in a small sized enclosure with versatile mounting options. The C−1806−10 covers a frequency range of 6 to 18 GHz and offers exceptional performance. It features excellent coupling flatness (±0.3 dB typical), good directivity (16 dB typical at 12 GHz), and excellent return loss (31 dB typical at 12 GHz). With the ability to pass DC current from input to output, it supports various applications such as cellular infrastructure, military systems, and lab use. This versatile coupler provides reliable and accurate power sampling while minimizing reflections and amplitude ripple...

Erie Technological Products

Erie Technological Products, October 18, 1965 Electronics Magazine - RF CafeErie Technological Products, located in my adopted hometown of Erie, Pennsylvania, was a re-branding of Erie Resistor Company as the concern had begun manufacturing a wide variety of discrete electronic devices - resistors, capacitors, feed-through filters, silicon rectifiers. The Erie Resistor complex on 12th Street in Erie occupies a huge amount of real estate on both sides of the road. The overhead foot bridge can be seen in this photo. The buildings have long been vacated and stand with many others as reminders of the thriving manufacturing center that Erie once was. We still have a good bit of manufacturing here, but nothing like back in the hey days of the last century.

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 Anritsu for Their Support!

Anritsu (electronics test equipment) - RF CafeAnritsu has been a global provider of innovative communications test and measurement solutions for more than 120 years. Anritsu manufactures a full line of innovative components and accessories for RF and Microwave Test and Measurement Equipment including attenuators & terminations; coaxial cables, connectors & adapters; o-scopes; power meters & sensors; signal generators; antenna, signal, spectrum, & vector network analyzers (VNAs); calibration kits; Bluetooth & WLAN testers; PIM testers; amplifiers; power dividers; antennas. "We've Got You Covered."

Wednesday the 30th

Capacitors as Transducers

Capacitors as Transducers, July 1968 Radio-Electronics - RF CafeCapacitors have been used as transducers in one form or another since their electrical characteristics were first discovered. An electrical transducer is a device that converts some form of energy into an electrical signal. This transformation allows for the measurement, detection, or communication of various physical phenomena. There are various types of electrical transducers, each designed to convert specific types of physical quantities into electrical signals. Some common types of electrical transducers include: pressure, temperature, strain, light sensors, accelerometers, microphones, ultrasonic, magnetic, gas, and position and displacement. Back in the 1980s I worked as an electronics technician (pre-BSEE degree from UVM) for a company in Vergennes, Vermont, called Simmonds Precision Products. Their products were fuel measurement systems primarily for commercial and military aircraft. The sensors / transducers were capacitive in nature, consisting of coaxial tubes which stood vertically in the fuel tanks and used the fuel as a dielectric to vary the capacitance according to its ratio relative to air between the tubes. The transducers were positioned at strategic locations within the tank to provide an accurate measure of fuel regardless of the attitude and acceleration of the aircraft...

More Sensitivity from Your Transistor Radio

More Sensitivity from Your Transistor Radio, January 1969 Electronics World - RF CafeWhere else on the Internet other than RF Cafe can you go for a daily helping of electronics-related material that ranges from the very beginnings of our chosen vocation through to the latest leading edge developments? That Q is rhetorical of course - and self-serving to boot ;-) This handy-dandy trick for enhancing the signal on your AM radio appeared in a 1969 issue of Electronics World magazine. I remember doing this magnet "tuning" technique on my small, el cheapo pocket transistor radio that I carried with me when wiring houses and buildings while working as an electrician many moons ago after high school. It often made the difference between being able to listen to my preferred AM station in Annapolis, MD - WNAV - and having to settle for Public Radio concerts. The "NAV" part of WNAV probably derives from "naval" both due to the U.S. Naval Academy being there and the fact that the entire Annapolis area is very water-centric, being located on the Chesapeake Bay and multiple surrounding tributaries. I do not miss the long, hot, extremely humid summers of boyhood. BTW, since I still listen to AM radio part of the day, I grabbed a magnet and ran it along the area where the internal AM ferrite rod antenna is located in my 1970s vintage Magnavox Model 789 AM / FM / Shortwave radio and sure enough, I was able to locate a peak in reception...

ConductRF Flexible Performance RF Cable to 18 GHz

ConductRF Flexible Performance RF Cable Assemblies to 18 GHz August 2023 - RF CafeConductRF's LSA series of Low Loss, Performance Flexible RF Cable Assemblies, provide microwave system designers with a versatile solution for most applications. Here we offer customers a solution for 0.086" dia. cable that facilitates greater flexibility and handling or, 0.141" dia. that exploits the same great performance but with almost half the loss. Connector options include SMA, Type-N, TNC & SMP that provide excellent VSWR between DC and 18 GHz, also solutions for MCX & SMB are available in a wide array of configurations. These assemblies are built using our own double shielded, FEP jacketed cable, that was developed specifically for performance solutions. With shielding effectiveness exceeding 90 dB through 18 GHz, these cables minimize the threat of cross-talk effect...

Akihabara Tokyo's "Radio Row"

Akihabara Tokyo's "Radio Row", May 1966 Popular Electronics - RF CafeThe September 1932 issue of Radio Craft magazine contained an article titled, "Radio a la Cortlandt Street!," the original "Radio Row" located at the corner of Cortlandt and Washington Streets in Manhattan (the intersection does not appear to exist anymore). It was a mecca of new and used electronics components and assemblies. After World War II there was a huge supply of surplus parts and equipment made available to the public as a means to clear out inventory and also as a "thank you" to the citizens who voluntarily donated critically needed panel meters, tuning capacitors, connectors, and other items to the War Department. That really helped the market boom. Post-war electronics magazines were chock full of ads by dealers selling surplus electronic and mechanical supplies. Most big cities of the era had a Radio Row, including Akihabara in Tokyo. This 1966 Popular Electronics magazine article tells its story...

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...

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.

Tuesday the 29th

TV Pix to Come from Moon

TV Pix to Come from Moon - RF CafeNASA's Surveyor series of lunar landers were launched between 1966 and 1968, following the preceding controlled-crash-landing Ranger probes. Being the May 1961 issue of Radio-Electronics magazine, the news item showing an artist's concept drawing of the proposed Surveyor is impressively close to the final product, shown in the photo to the left, taken by Apollo 12 astronauts after setting down very close to it. In other news, severe smog in the Los Angeles area was found to highly attenuate experimental communications in the 36 GHz realm, although it had little effect below that. Looking at the International Telecommunications Union (ITU) charts of measured atmospheric attenuation levels, no pronounced peak under normal wet or dry conditions occurs at 36 GHz...

European Microwave Exhibition 2023

European Microwave Exhibition 2023 - RF CafeThe European Microwave Week (EuMW) 2023 will take place in Berlin, Germany from September 19th to 21st, 2023. Spanning three days, the European Microwave Exhibition is your ticket to mingling with the industry leaders driving the future of the microwave industry. This event is free to attend and will provide access to over 300 international exhibitors and take the opportunity of face-to-face interaction with those developing the future of RF/microwave. The EuMW 2023 will be the hotspot for networking on a global scale, breaking boundaries, and sharing insights that transcend time zones. But it's not just about the talk - it's about experiencing innovation firsthand. This event will be a showcase of cutting-edge product innovations that are set to redefine the microwave landscape. Hands-on demos will whisk you away into a world of tech marvels...

Lithium Ion Polymer (Li-Po or Li-Poly) Battery Characteristics

Lithium-Polymer (Li-Po or Li-Poly) Battery Characteristics - RF CafeLightweight lithium ion polymer (Li-Poly) batteries have made a huge impact on the performance, and subsequently the acceptance of electric systems as a replacement for the traditional nitromethane (nitro) and gasoline power systems in model airplanes and helicopters. Their energy density (Wh/kg is the most common unit of measure), combined with the relatively new and extremely powerful brushless motors, electric power systems are rivaling the internal combustion systems in terms of both energy and duration. Development of both the brushless motors and the advanced battery technologies has been, both officially and unofficially, a joint venture between government and civilian research and development efforts. If you keep up with the news headlines for NASA, defense contractors, green energy researchers, and similar organizations, you have witnessed the plethora of new vehicles that have been built tested, and in may cased deployed in the field. These range from micro air vehicles that carry surveillance equipment for the military, to hybrid and fully electric passenger vehicles, vastly improved...

TotalTemp Synergy Nano Temperature Controller

TotalTemp Technologies: Synergy Nano Temperature ControllerTotalTemp Technologies, a worldwide leading provider of research laboratory and production temperature chambers and thermal platform equipment, introduces their model Synergy Nano Multi-Channel Process Controller and Data Logger for precision temperature testing. The Nano equips temperature chambers and thermal platforms with capable and reliable controlling functionality. The very flexible and customizable Nano supports the ability to optimize equipment and processes. All are feature rich while still being easy to use. Features include long duration logging, configurable inputs and outputs, alarms, hot and cold regulation, displays, auto resume, remote programmability options plus easy to build and reproduce local test profiles. The Synergy Nano has a universal 120-230 volts AC power input. Similar platforms and chambers are typically not universal voltage...

Simplified Coil Calculation

Simplified Coil Calculation, May 1932 Radio-Craft - RF CafeThis might be one of the earliest printed instances of Harold A. Wheeler's simplified formulas for the three basic inductor forms. Wheeler is credited with having devised the first automatic volume control (AVC) using diode envelope detection. We all use them on a regular basis, but for most the origin was never known or has long since been forgotten (I fall into the latter category). I did some research on Wheeler's inductance formulas a few months ago while working on what is now titled "RF Cafe Espresso Engineering Workbook™," so it was sort of déjà vu when this blurb appeared in a 1932 edition of Radio-Craft magazine...

Promote Your Company on RF Cafe

Sponsor RF Cafe for as Little as $40 per Month - RF CafeBanner Ads are rotated in all locations on the page! RF Cafe typically receives 8,000-15,000 visits each weekdayRF Cafe is a favorite of engineers, technicians, hobbyists, and students all over the world. With more than 17,000 pages in the Google search index, RF Cafe returns in favorable positions on many types of key searches, both for text and images. Your 728x90-px and 160x600-px Banner Ads are displayed on average 225,000 times per year! 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. If you need your company news to be seen, RF Cafe is the place to be...

Many Thanks to San Francisco Circuits for Continued Support!

San Francisco CircuitsSF Circuits' specialty is in the complex, advanced technology of PCB fabrication and assembly, producing high quality multi-layered PCBs from elaborate layouts. With them, you receive unparalleled technical expertise at competitive prices as well as the most progressive solutions available. Their customers request PCB production that is outside the capabilities of normal circuit board providers. Please take a moment to visit San Francisco Circuits today. "Printed Circuit Fabrication & Assembly with No Limit on Technology or Quantity."

Monday the 28th

Mini-Radar Will Probe Asteroid

Mini-Radar Will Probe Asteroid - RF Cafe"The smallest radar to fly in space has been delivered to ESA for integration aboard the miniature Juventas CubeSat, part of ESA's Hera mission for planetary defense. The radar will perform the first radar imaging of an asteroid, peering deep beneath the surface of Dimorphos - the Great Pyramid-sized body whose orbit was shifted last year by the impact of NASA's DART spacecraft. 'This delivery marks a definite milestone,' comments Alain Herique of Institut de Planetologie et d'Astrophysique de Grenoble (IPAG) at the University Grenoble Alpes in France, the instrument's principal investigator. 'We have been working hard in recent weeks to finalize the radar for its handover. But this is far from the end of our involvement. IPAG and our project partners will be following the process of integration, especially in terms of connection with the rest of the CubeSat, to optimize the performance of the finished instrument, and to calibrate its performance to ensure we interpret our science data..."

Mathcad File Containing Frickey's Equations

Mathcad File Containing Frickey's Equations - RF CafeLouis J. was kind enough to provide his Mathcad file (please let me know if you have an old Windows version for sale) for conversion back and forth between ABCD-, h-, s-, T-, y, and Z-parameters. Says he: "Attached is the Mathcad worksheet containing all of Frickey's work, both what you published and what the original paper included that you did not publish. It does not contain the "close the loop" testing I performed, but all the equations are identical to the ones in my test sheet. The equations are all configured for symbolic manipulation. To use with live data, copy the equation(s) of interest to another worksheet, change the <ctrl>= to a <colon>= and define the variables. This is something any Mathcad user should know how to do. Tip: If one were interested, they could copy the content of any equation object in Mathcad (not the equation object itself) and paste it into a generic text editor. The result is an equation using Mathcad functions in RPN format. (Lots of parens so each operation has one or two variables. Each operation consists of the operator followed by the one or two variables. Mathcad functions are preceded by an '@' symbol..."

Antenna and Radome Sr. Principal Design Engineer

/2023/Antenna-Radome-Design-Sr-Principal-Engineer-RTX-6-1-2023.htm"> Antenna and Radome Design Senior Principal Design Engineer Needed by RTXRTX / Raytheon is seeking an /2023/Antenna-Radome-Design-Sr-Principal-Engineer-RTX-6-1-2023.htm"> Antenna and Radome Senior Principal Design Engineer at their Tucson, AZ, location. This position is eligible for a minimum of $40,00 Sign-On Bonus. The candidate will be responsible for leading and shaping antenna, radome, and antenna measurement system technology within the Company. The selected candidate will also be expected to lead diverse teams, provide technical oversight, delegate tasks, and work with the Engineering organization to establish technology roadmaps, enable modernization, and contribute to general innovation. In addition, the candidate will work with government personnel and programs, and define and refine requirements to validate hardware compliance. Responsible for development of antenna or radome hardware and requirements, working with interdisciplinary engineering teams including thermal, structural, mechanical, systems, etc., working with antenna manufacturing suppliers, analyzing simulation or test data to verify performance to requirements...

Bell Telephone Laboratories

Bell Telephone Laboratories, July 1959 Electronics World - RF CafeBell Telephone Laboratories was largely responsible for designing and building a communications system that was the envy of the world. Innovation on the part of Bell engineers, manufacturing staff that produced the equipment, and technicians who serviced the systems deserve the credit as do management types who made funds and opportunity available to the aforementioned. As the number of telephone service subscribers grew and reliability became even more vital to business, law enforcement, and national defense, new methods had to be devised. In the late 1950s, Bell introduced the concept of wireless microwave links at 11 GHz (X band), which at the time X band was primarily used (at 10 GHz) by precision approach aircraft radar. This advertisement in a 1959 issue of Electronics World magazine promoted Bell's achievement...

Promote Your Company on RF Cafe

Sponsor RF Cafe for as Little as $40 per Month - RF CafeBanner Ads are rotated in all locations on the page! RF Cafe typically receives 8,000-15,000 visits each weekdayRF Cafe is a favorite of engineers, technicians, hobbyists, and students all over the world. With more than 17,000 pages in the Google search index, RF Cafe returns in favorable positions on many types of key searches, both for text and images. Your 728x90-px and 160x600-px Banner Ads are displayed on average 225,000 times per year! 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. If you need your company news to be seen, RF Cafe is the place to be...

Many Thanks for Alliance Test Equipment's Support!

Allied Test Equipment Products - RF CafeAlliance Test Equipment sells used / refurbished test equipment and offers short- and long-term rentals. They also offer repair, maintenance and calibration. Prices discounted up to 80% off list price. Agilent/HP, Tektronix, Anritsu, Fluke, R&S and other major brands. A global organization with ability to source hard to find equipment through our network of suppliers. Alliance Test will purchase your excess test equipment in large or small lots. Blog posts offer advice on application and use of a wide range of test equipment. Please visit Allied Test Equipment today to see how they can help your project.

Sunday the 27th

Electronics Themed Crossword for August 27th

Electronics Themed Crossword Puzzle for August 27th, 2023 - RF CafeThis custom RF Cafe electronics-themed crossword puzzle for August 27th contains words and clues which pertain exclusively to the subjects of electronics, science, physics, mechanics, engineering, power distribution, astronomy, chemistry, etc. If you do see names of people or places, they are intimately related to the aforementioned areas of study. As always, you will find no references to numbnut movie stars or fashion designers. Need more crossword RF Cafe puzzles? A list at the bottom of the page links to hundreds of them dating back to the year 2000. 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...

Please Thank Werbel Microwave for Continued Support!

Werbel MicrowaveWerbel Microwave is a manufacturer of RF directional and bidirectional couplers (6 dB to 30 dB) and RF power dividers / combiners (2− to 16−way) with select models operating up to 26.5 GHz and 100 W of CW power (3 kW peak). All are RoHS and REACH compliant and are designed and manufactured in our Whippany, NJ, location. Custom products and private label service available. Please take a couple minutes to visit their website and see how Werbel Microwave can help you today.

Friday the 25th

Repairing Ferrite Rods

Repairing Ferrite Rods, August 1969 Radio-Electronics - RF CafeWhen I saw this article on "Repairing Ferrite Rods," it caught my interest because I remember breaking one in a transistor radio not from dropping it, which might have been excusable, but from screwing around with it. It probably wasn't too far removed in time from when the article appeared in Radio-Electronics magazine, although I was not reading such publications at the time (I was 11 years old). I don't recall exactly how I snapped it, but it broke under the windings and I was sure I had ruined it. Fortunately, it still worked just fine, even without making any attempt to glue it back together. A ready stock of Duco Cement was always on-hand from my model airplane and rocket building hobby, but given that the break was under the windings and not readily accessible, there was good chance more damage would be done trying to squeeze glue into it. I don't recall whether the pointer position on the dial was still lined up with where the radio station used to be, but all that mattered was escaping what could have been a disaster for me. In those days, money for a new radio was not just laying around...

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.

Amazing Apparatus of the Gay Nineties

Amazing Apparatus of the Gay Nineties, January 1965 Popular Electronics - RF CafeCarleton Phillips was not minimizing his predecessors when he wrote this 1966 Popular Electronics magazine article marveling at the accomplishments made in "Gay Nineties" (1890's) in spite of their relatively crude resources. Seven decades had passed since then. A similar article could be written today, five decades hence, about today's knowledge and technology compared to that of the mid 1960's. For instance, DNA had not yet been sequenced, 3D printing did not exist, Al Gore had not invented the Internet, MRI machines were not available, there were no cellphones, PC's were only a dream, booster rockets could not land self-powered for re-use, TV's used CRT displays, vacuum tubes still dominated consumer electronics, automobile air bags weren't saving lives and limbs, Lasik surgery wasn't even in an experimental stage, supersonic flight was (and sadly is again) the sole domain of the military airplanes, satellite-based global navigation was non-existent, and the list goes on. Someday, an AI machine will write yet another a similar article about the crudeness of technology in 2023.

Measurement of Permittivity Advances Radio Telescope Receivers

Measurement of Permittivity Advances Radio Telescope Receivers - RF Cafe"Researchers in Japan have invented a novel method to measure the permittivity of insulators 100 times more accurately than before. This technology is expected to contribute to the efficient development of sensitive radio receivers for radio telescopes as well as to the development of devices for the next generation communication networks, 'Beyond 5G/6G.' Permittivity is a value that indicates how electrons inside an insulator react when a voltage is applied to the insulator. It is an important parameter for understanding the behavior of radio waves as they travel through insulators. In the development of telecommunications equipment, it is necessary to accurately determine the permittivity of materials used for circuit boards and building columns and walls. For radio astronomy, researchers also need to know the permittivity of components used in radio receivers. By devising a calculation method for electromagnetic wave propagation, the research team developed an analytical algorithm that derives the permittivity directly rather than by approximation. The team, consisting of researchers and engineers from the National Astronomical Observatory of Japan (NAOJ)..."

s- to h- T- Y- Z- Parameter Conversions

s- to h- T- Y- Z- Parameter Conversion - RF CafeI recently was made aware that all four "h- from T-Parameters" conversion equations had errors. Also, Z22-from-T had a sign error. They have all been corrected (marked with †). Thanks to Louis J. for bringing this to my attention, and for graciously providing the new equations! He generated a Mathcad worksheet for converting back and forth between all parameter sets. Says Louis, "[There] is a bug in Frickey's document and you are unlikely to be able to do anything about it. The h-Parameters from T-Parameters equation set fail to close the loop. All four equations have an error that is in the same direction and of roughly the same magnitude as measured in percentage. I suspect a problem with the denominator value. I verified this assumption by adding in an offset (complex) into the denominator and found all values fell into place. Without this offset, these simply refused to 'close the loop' or match the results from other tools. I am far from a mathematician, so I tend to rely on Mathcad to do my algebra, trig and calculus. I started with the working T from h parameter equation set. It handled this matrix equation system fairly easily..."

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 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.

Thursday the 24th

Radio Libertad - a REAL Mystery Station

Radio Libertad - a REAL Mystery Station, September 1969 Electronics Illustrated - RF CafeHa, when I first saw this "Radio Libertad - A Real Mystery Station" in a 1969 issue of Electronics Illustrated magazine, I though it said, "libtard." Not being a Spanish speaker, it did not strike me as the Spanish word for "liberty." Libertad is also the name of a coin minted - both in silver and in gold - by Mexico. There is also currently a Radio-Libertad (RL), which is a group of exiled Cubans in south Florida that broadcasts messages (31 m, 9955 kHz) to their families and brethren still captive on the Communist-controlled island. It is similar to Radio Free Europe / Radio Liberty and Voice of America (VOA). Radio Libertad's mission back then was the same as it is today, the difference being we know from where the transmissions originate. Rumor had it the CIA was behind the original RL. This particular story references Radio Swan, which was a pirate radio station run by the CIA, similar to its operations in Swan Islands and the airborne Blue Eagle incident. This video shows a Lockheed Constellation as being the aircraft from which it was broadcast, but the declassified CIA document claims...

Precision Distance-Measuring Microchip

Precision Distance-Measuring Microchip - RF Cafe"By combining optical trapping and frequency combs - two widely used but unrelated developments in advanced physics - researchers devised a way to measure micro-dimensions in opaque materials. It's not unusual for a technical Nobel Prize to be awarded in recognition for an advancement that's already had practical applications, usually in well-defined scenarios, such as blue LEDs (2014) or optical fibers for communications (2009). Now, physicists at Delft University of Technology (Netherlands) have gone further, building a new technology on a microchip by combining two Nobel Prize-winning techniques - apparently the first time this has occurred. Their microchip could measure distances in materials at high precision, including for underwater or medical imaging. Because the technology uses sound vibrations instead of light, it's useful for high-precision position measurements in opaque materials. These mechanical frequency combs are poised to bring the applications and utility of optical frequency combs into the mechanical domain..."

Fixtures Form Semirigid Coax

Fixtures Form Semirigid Coax, February 28, 1964 Electronics Magazine - RF CafeA well-laid-out and routed chassis, control panel, equipment rack, or circuit breaker panel has always invoked the same sort of appreciation and awe in me that a Rembrandt painting invokes in an art cognoscente or a Beethoven concert invokes in a music aficionado. Many moons ago when I worked as an electrician, I prided myself in obsessively neat and orderly runs of conduit and Romex™ cable (with no twists), squarely mounted receptacle and switch boxes, and rigid compliance with NEC requirements. Once I entered into the RF and microwave realm, an entirely new kind of eye candy appeared in the form of semi-rigid coaxial cable and waveguide runs. Knowing the technical (electrical) requirements and limitations based on power, wavelength, and VSWR concerns served to enhance the appreciation. Electrical wiring has its own unique requirements for bend radii, enclosure fill, and voltage levels, due to heating, mechanical stress, and voltage induction issues. RF transmission media adds to that signal reflections due to contamination and cross-section perturbations, dissimilar junction spurious mixing products, microphonics, common mode currents...

Werbel 2-Way Power Divider for 0.5-8 GHz

Werbel Microwave Intros 2-Way Power Divider/Combiner for 0.5-8 GHz - RF CafeModel D−2066 from Werbel Microwave is a 2−way power splitter covering 500 MHz to 6 GHz in a small sized enclosure with versatile mounting options. Four through-holes allow for traditional top-down chassis mounting. Threaded holes on the input and output sides allow for rack panel mounting. The compact size aluminum enclosure weighs only 3 oz. (85 g) making it suitable for array-panel and mobile vehicle applications. Insertion loss is low at only 0.9 dB at 6 GHz. Return loss and isolation are high performance. The device is RoHS compliant. This part has versatile mounting options. Standard thru holes mount the part from the broad surface, while threaded holes allow for bulkhead rack-mountable mounting...

Westernizing Japan Electronics

Westernizing Japan Electronics, December 13, 1965 Electronics Magazine - RF CafeHere is an editorial excerpt from a 1965 issue of Electronics magazine that could be from a contemporary news publication: "If U. S. manufacturers continue to abandon their engineering and production for Japanese products, they are headed for oblivion because they cannot compete with the purely merchandising organizations such as Sears, Roebuck & Co. and Montgomery Ward which buy Japanese products too." Of course you could easily substitute South Korea, China, Taiwan, or any other now-prominent technology company in place of Japan. American economic "experts" assured us in the 1990s that we no longer needed to manufacture anything; rather, we would become a service and retail economy. That worked out real well, eh? What we really became was dependent on the rest of the world for our goods, and were forced to surrender intellectual property (IP), erstwhile closely guarded national defense secrets (handing over ICBM guidance systems, high precision CNC machinery, semiconductor processing equipment, etc.) for the privilege of establishing...

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...

Thanks to Temwell for Their Support!

Temwell (filters) - RF CafeTemwell is a manufacturer of 5G wireless communications filters for aerospace, satellite communication, AIoT, 5G networking, IoV, drone, mining transmission, IoT, medical, military, laboratory, transportation, energy, broadcasting (CATV), and etc. An RF helical bandpass specialist since 1994, we have posted >5,000 completed spec sheets online for all kinds of RF filters including helical, cavity, LC, and SMD. Standard highpass, lowpass, bandpass, and bandstop, as well as duplexer/diplexer, multiplexer. Also RF combiners, splitters, power dividers, attenuators, circulators, couplers, PA, LNA, and obsolete coil & inductor solutions.

Wednesday the 23rd

Electronics-Themed Comics

Electronics-Themed Comics, October & November 1968 Radio-Electronics - RF CafeI haven't watched much television for the last thirty years, so I don't know if having someone get electrocuted is still considered as funny as it used to be. Maybe that went out with the Three Stooges. In the 1960s and 70s, just about every Prime Time comedy show ran an episode where somebody's tooth filling was picking up radio broadcasts. I particularly remember the Gilligan's Island episode called "Hi-Fi Gilligan" where he became an AM radio receiver when a jolt to the jaw affected the filling in a molar (those AM signals travelled quite a distance to that "uncharted desert isle"). These two electronics-themed comics from 1968 Radio−Electronics magazine hits on both of those themes...

EA Blog: The Power of Regenerative Loads

EA Blog: The Power of Regenerative Loads - RF CafeEA Elektro-Automatik (EA), a manufacturer of DC power supplies loads, and turnkey power racks, just posted a new blog entitled, "Reaping Energy Savings: The Power of Regenerative Loads." It begins, "Programmable DC power supplies have long been instrumental in power electronics and battery testing. These supplies are extensively used for performance testing and product characterizations. However, a common issue arises when dealing with excess energy generated during burn-in tests, battery cycling or discharging energy storage systems before shipment. Traditionally, this surplus energy is dissipated as heat using resistive load banks or electronic loads. While seemingly simple, this approach brings about thermal management and noise challenges, making it less straightforward than it appears. This begs the question: can this surplus power be recycled and put to use within the facility? In recent years, there has been a growing push for industrial facilities to become more eco-friendly and operate with greater energy efficiency. Regenerative electronic loads present an energy-saving solution as they redirect the load power back to the utility..."

Belmont Model 6D121 Schematic & Parts List

Belmont Model 6D121 Schematic & Parts List, February 1948 Radio News - RF CafeThis "drive-by" schematic and parts list for the Belmont Model 6D121 vacuum tube tabletop radio appeared in the February 1948 issue of Radio News magazine. I refer to them as "drive-by" because there was no description or maintenance verbiage provided. One of the key innovations that Belmont Radio is remembered for is its development of the "All-Wave" radio, which allowed listeners to receive broadcasts from around the world. This was a significant advancement in radio technology, as previous radios were limited to receiving local broadcasts. Belmont Radio's All-Wave radio was widely popular and helped to establish the company as a leading manufacturer of radio equipment. Model 6D121 is a tabletop radio in a "modern" plastic case covering the AM band with pushbutton tuning. The thumbnail at the left is from the RadioMuseum.org website - a great source for research on vintage vacuum tube radios...

IPP-5027, Wideband 4:1 Impedance Transformer

Innovative Power Products IPP-5027, Wideband 4:1 Impedance Transformer - RF CafeInnovative Power Products (IPP), with more than 30 years of experience designing & manufacturing RF & microwave passive components, introduces model IPP-5027, a wide-band, a single-ended impedance transformer that operates from 30 to 1000 MHz. This small, surface mount impedance transformer has a 4:1 transformation ratio, changing the impedance from 50 ohms at J1 to 12.5 ohms at J2. The IPP-5027 has a 25 watt average power rating with low insertion loss and VSWR of 1.45:1. The IPP-5027 is a small, SMD transformer that is shipped on tape and reel for pick and place applications, providing a cost-saving solution. Single-Ended Transformers are used to connect transmission lines of differing impedances. IPP offers single-ended impedance transformers for antenna drivers, amateur radio, commercial and military applications in frequencies ranging from 20-2500 MHz...

2 Halos Stacked for 2 Meters

2 Halos Stacked for 2 Meters, January 1965 Popular Electronics - RF CafeThe stacked halo antenna is a compact configuration for obtaining a nearly omnidirectional radiation pattern with nearly 8 dB of gain. An ideal half-wave dipole antenna provides 2.15 dB, so adding 5 to 6 more decibels by merely stacking two halo antennas (which are essentially curved half-waves) might seem like getting more than the sum of the parts. That extra gain is obtained by concentrating the vertical radiation pattern lower to the horizon as compared to a straight half-wave, even though the horizontal pattern loses a bit of gain contribution from the translation to a nearly omnidirectional nature. There is nowadays a plethora of information available on the Internet regarding stacked halo antennas, but in 1965, this Popular Electronics magazine article was one of only a few readily accessible sources other than college textbooks and scholarly papers (of course the ARRL Antenna Handbook was and still is a prime source)...

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 Berkeley Nucleonics for Continued Support!

Berkeley Nucleonics Corp - RF CafeBerkeley Nucleonics Corporation (BNC) is a leading manufacturer of precision electronic instrumentation for test, measurement, and nuclear research. Founded in 1963, BNC initially developed custom pulse generators. We became known for meeting the most stringent requirements for high precision and stability, and for producing instruments of unsurpassed reliability and performance. We continue to maintain a leadership position as a developer of custom pulse, signal, light, and function generators. Our designs incorporate the latest innovations in software and hardware engineering, surface mount production, and automated testing procedures.

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