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Homepage Archive - September 2022 (page 1)

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

Wednesday the 7th

Plastic-Film Capacitors

Plastic-Film Capacitors, July 1965 Electronics World - RF CafeIf you like pronouncing long, complex chemical names, you'll really enjoy this "Plastic Film Capacitors" article from a 1967 issue of Electronics World magazine. It was written by Walter Lamphier of Sprague Electric, a long-time manufacturer of capacitors of all sorts. As of 1992, Vishay has owned Sprague (founded in 1926 by Robert Sprague), but has strategically retained the very familiar Sprague name as part of theirs. Anyway, a lot of information is provided about the relatively new (at the time) plastic-film construction. A contemporary article on the same subject would no doubt include a whole host of new chemical compounds not even invented in 1967. This particular issue of Electronics World reports on a few other kinds of capacitor constructions popular at the time, including paper, ceramic, glass, and electrolytic...

Lidar with New Chip-Based Beam Steering Device

Lidar with New Chip-Based Beam Steering Device - RF Cafe"Researchers have developed a new chip-based beam steering technology that provides a promising route to small, cost-effective, and high-performance lidar systems. Lidar, or light detection and ranging, uses laser pulses to acquire 3D information about a scene or object. It is used in a wide range of applications such as autonomous driving, 3D holography, biomedical sensing, free-space optical communications, and virtual reality. 'Optical beam steering is a key technology for lidar systems, but conventional mechanical-based beam steering systems are bulky, expensive, sensitive to vibration, and limited in speed,' said research team leader Hao Hu from the Technical University of Denmark. 'Although devices known as chip-based optical phased arrays (OPAs) can quickly and precisely steer light in a non-mechanical way, so far, these devices have had poor beam quality and a field of view typically below 100°..."

Mac's Radio Service Shop: A Windy Subject

Mac's Radio Service Shop: A Windy Subject, March 1953 Radio & Television News - RF CafeIt is a pretty good bet that most multi-element TV aerials you find on rooftops and even on ancient towers were decommissioned years ago. They have been replaced either with cable (whether via CATV or Internet) or satellite dishes. A few hold-outs still use them for local over-the-air broadcast stations and/or even FM radio reception. There was a time, though, that photographs taken looking across a vast expanse of house roofs showing an endless array of antennas and guy wires was a sign of "modern" living. Most were erected by Harry Homeowner types or minimally qualified service technicians, and were well-known for toppling, twisting, bending or un-aligning when stiff winds were imposed upon them. This story-lesson from the March 1953 edition "Mac's Radio Service Shop," a regular feature in Radio & Television News magazine, provides a bit of analysis on causes of failure due to improper guying and why many people's "One Hoss Shay" of an installation failed despite their best efforts...

Berkeley Nucleonics 8060(C) Impedance Tuner/Generator

Berkeley Nucleonics Model 8060(C) Impedance Tuner/Generator - RF CafeThis new state of the art Model 8060 Impedance Tuner / Generator from Berkeley Nucleonics puts reliable, repeatable noise parameter measurements in your lab at about $10k, an order of magnitude below what a mechanical table top system might cost. The compact digital device offers a standard frequency range from 0.1 MHz to 6.0 GHz and can be customized to tuned up or down for application-specific needs. A cryogenic option (Model 8060C) provides greater performance capability allowing cold noise parameter measurements. The small size and fully electronic design permit noise-parameter measurements of packaged and on-wafer devices, ensuring flexibility and short test times. The Model 8060C is designed to work down to absolute zero temperature (Zero Kelvin) use primarily in Radio Astronomy and Space Exploration, cryogenic Nuclear Magnetic Resonance (NMR), and Quantum Computers. A host of MATLAB and other scripts are provided to allow users to take advantage of their own VNA, Spectrum Analyzer, and Noise Source...

Co-Inventors Quiz

Co-Inventors Quiz, January 1965 Electronics World - RF CafeRobert P. Balin created many electronics-related quizzes for Popular Electronics magazine. I have posted lots of them here on RF Cafe, and will post more in the future. He designed quizzes for Electronics World magazine before the publication's name changed to Popular Electronics. Most of the Popular Electronics era quizzes were pretty easy for anyone who has been in the electronics realm a few years. However, this "Co-Inventors Quiz" from a 1965 issue of Electronics World is a real head scratcher. I was only able to get two out of 10 answers correct. It would take someone who is a physics historian to even come close to acing it - that or I'm really just lacking in historical knowledge. Bon chance.

Post Your Engineer & Technician Job Openings on RF Cafe for Free

/jobs.htm" target="_top"> 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 /jobs.htm" target="_top">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...

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.

Tuesday the 6th

Flexible Coaxial Cable

Flexible Coaxial Cable, April 1946 QST - RF CafeIf anything qualifies for meeting the criteria of the old adage that says "Necessity is the mother of invention," it is coaxial transmission cable. Wireless communications during World War II was the necessity that drove the rapid development and continuous improvement of coax. Other than materials technology for wire, dielectric, protective jacket, etc., the basics of coax cable have not changed since this article appeared in a 1946 issue of QST magazine. It was during the war that polyethylene was developed and adopted as a dielectric material much superior to previously used copolene. Understanding of how electromagnetic fields propagate within and, under non-ideal conditions - on the outside of the cable has increased significantly thanks for refined theory and high speed computer simulations. RG-58 were early 50 Ω coax types, and RG-59, RG-11, and RG-6 were early 75 Ω coax types that are all still in significant use today...

Empower RF 1-2 GHz, 40 kW SSPA for Radar, Test, and EW

Empower RF Systems 1 to 2 GHz, 40 kW Transmitter for Radar, Test, and EW - RF CafeEmpower RF Systems Model 2237 is a high performance, liquid cooled, pulsed transmitter operating from 1 to 2 GHz, designed for maximum waveform flexibility. Another variation of Empower's Gen3 platform, the 2237 is configured for L-Band radar, test, and EW applications. The deployment of the 2237, along with the previously announced 2244, further solidifies the solid state, high power, liquid cooled L-Band product baseline that has been developed. This new modern architecture offers scalability for affordable upgrade paths to future power needs by adding hardware to an existing system. The 2237 transmitter layout consists of a system controller in a 3U 19-inch rack unit and 16 hot swappable 2U amplifier drawers with each amplifier drawer containing an integrated power supply in its 2U chassis. There is no separate system level power supply...

Winding Your Own Output Transformers

Winding Your Own Output Transformers, September 1970 Popular Electronics - RF CafeEven if you no longer - or never did - have the need to wind your own audio frequency output impedance matching transformers, this article from a 1970 issue of Popular Electronics magazine provides good insight into the factors necessary for consideration when doing so. One particularly nice feature here is that power handling is taken into account, including wire size to use for the primary and secondary (or multiple outputs). At audio frequencies, where the transformer is driving speakers with typical impedances of 4, 8, or 16 ohms, you do not need to worry too much about parasitic capacitance and inductance. The basic equations do a pretty good job of predicting performance. Author Ed Francis explains how to modify a junk-box laminated core transformer to work, as well as providing a table of enameled wire size ampacities and turns per linear inch. An example of how to perform all the steps is given...

Highway Hi-Fi by Chrysler

Highway Hi-Fi by Chrysler - RF CafeBefore magnetic cassette and 8-track tape decks, then compact disks (CD's) and digital video disks (DVD's, although now called digital versatile disks) provided for personalized music selections while on the road, Chrysler featured an in-dash record player dubbed "Highway Hi-Fi." Just as the old Walkman type players suffered from skips due to shocks, the automobile-based record player had similar issues, only more severe. In fact, the Highway Hi-Fi player needed a high pressure tone arm that subjected a lot of wear on record grooves. Because of that, special heavy-duty records were pressed by Columbia Records in an LP format that crammed a full hour of content on each side of the album. Accordingly, the selection of artists and songs was limited. Ultimately, the cost, complexity, and poor performance resulted in a failed idea. As the old saying goes, it's the pioneers who catch the arrows.

Farnsworth Models EK-081, 082, 083 Schematic & Parts List

Farnsworth Models EK-081, EK-082, EK-083, EK-681 Schematic & Parts List, August 1947 Radio News - RF CafeThese schematics & parts lists for the Farnsworth models EK-081, EK-082, EK-083, EK-681 radio were scanned from a 1947 issue of Radio News magazine. Most often a description of the radio's tuning procedure would be included a la an abbreviated version of the Sams Photofacts data, but sometimes only bare bones information was provided. Still, service shops and hobbyists appreciated having it made available because manufacturers usually only provided service information to authorized dealers. In the days of Internet, locating such things could prove nearly impossible. There are still many people who restore and service these vintage radios, and often it can be difficult or impossible to find schematics and/or tuning information. I keep a running list of all data sheets to facilitate a search...

RF & Electronics Symbols for Visio

RF Electronics Wireless Analog Block Diagrams Symbols Shapes for Visio - RF CafeWith more than 1000 custom-built symbols, this has got to be the most comprehensive set of Visio Symbols available for RF, analog, and digital system and schematic drawings! Every object has been built to fit proportionally on the provided A-, B- and C-size drawing page templates (or can use your own). Symbols are provided for equipment racks and test equipment, system block diagrams, conceptual drawings, and schematics. Unlike previous versions, these are NOT Stencils, but instead are all contained on tabbed pages within a single Visio document. That puts everything in front of you in its full glory. Just copy and paste what you need on your drawing. The file format is XML so everything plays nicely with Visio 2013 and later...

Many Thanks to Amplifier Solutions Corporation (ASC) for Continuing Support!

Amplifier Solutions Corporation (ASC) - RF Cafe ASC designs and manufactures hybrid, surface mount flange, open carrier and connectorized amplifiers for low, medium and high power applications using gallium nitride (GaN), gallium arsenide (GaAs) and silicon (Si) transistor technologies. ASC's thick film designs operate in the frequency range of 300 kHz to 6 GHz. ASC offers thin film designs that operate up to 20 GHz.

Monday the 5th

Electronics-Themed Comics

Electronics-Themed Comics, November 1959 Radio-Electronics - RF CafeMondays usually need help to keep spirits up. Even though this is a three-day holiday weekend (Labor Day) weekend in the U.S., it is just another Monday in the rest of the world. Accordingly, here are a handful of electronics-themed comics from a 1959 issue of Radio−Electronics magazine. You need to keep in mind the relative newness of televisions at the time, with the reverence toward - and frustration with - the technology. Lots of artists had fun poking fun at TV's and those who watched and serviced them. If you are in the U.S. and don't see this until after returning to work, have a happy Tuesday. BTW, there is a huge list of technology-themed comics at the bottom of the page - I've been posting them for a couple decades now...

Chip-Free Electronic Skin Senses Wirelessly

Chip-Free Electronic Skin Senses Wirelessly - RF Cafe"A team led by Massachusetts Institute of Technology (MIT) has devised an electronic skin that communicates wirelessly without requiring chips or batteries. Wearable sensors are ubiquitous thanks to wireless technology that enables a person's glucose concentrations, blood pressure, heart rate and activity levels to be transmitted seamlessly from sensor to smartphone for further analysis. Most wireless sensors communicate via embedded Bluetooth chips that are powered by small batteries, but these conventional chips and power sources may be too bulky for smaller, thinner and more flexible next-generation sensors. The team's new sensor design, detailed in Science, is a flexible 'e-skin' - a semiconducting film that conforms to the skin like electronic Scotch tape..."


The Radio Beginner

The Radio Beginner, April 1933 Radio-Craft - RF CafeAccording to Radio−Craft magazine founder and editor Hugo Gernsback, during the Roaring Twenties era in the U.S. - and around much of the world for that matter - interest in the burgeoning field of radio communications led to as many as half a million new entrants into the field each year. As the novelty of the still-mystical wireless craft wore off and/or enthusiasts discovered the technical aspects were too challenging, the numbers ebbed to a quarter of the peak. The Stock Market crash in the Fall of 1929 didn't help matters, either. By 1933, Gernsback was writing, "The radio beginner these days is in a paradise of his own; he has low-priced merchandise, he has an avalanche of new radio circuits, and radio tubes of every class and variety..."

Withwave Intros Absorptive RF Switch Modules

Withwave Intros Absorptive RF Switch Modules - RF CafeWithwave's RF Switch Modules have absorptive RF switches such as SP4T, SP8T, SP10T & SP12T according to switching applications and frequency range up to 44 GHz. They delivers high isolation, low insertion loss and fast switching time, making this devices ideal for RF signal routing in wireless infrastructure and applications up to maximum frequency range. External Connectors included 2.92 mm vertical launch connectors for all RF port. They are powered and controlled through USB 3.0 connector...

The Decibel: AWG Wire Size Rule of Thumb

The Decibel: AWG Wire Size Rule of Thumb, October 1931 QST - RF CafeIn 1931, QST reader John H. Miller, Electrical Engineer, of the Jewell Electrical Instrument Company, wrote to the editor regarding the story "What Is This Thing Called Decibel?," by James L McLaughlin and James J. Lamb, which appeared in the August issue of that year. Mr. Miller wished to inform (or remind) readers that the American Wire Gauge system for assigning sizes to wire cross-section ratios closely follows a decibel (i.e., logarithmic) relationship. Applying his information: A 28 AWG solid wire has a cross-section of 160 circular mils, so at 3 sizes larger, 25 AWG should be 320 circular mils. In fact, it is 320 circular mils (see table on the Copper Wire Properties & Gauge Conversions page). A 12 AWG solid wire has a cross-section of 5,630 circular mils, so at 3 sizes larger, 9 AWG should be 13,060 circular mils, and it is 13,090 circular mils. That verifies the 3 dB per three differences in gauge for two cases using small and large wire sizes. What about, say, 5 dB for 5 wires sizes in difference? Using 28 AWG again as a reference, a 5 dB increase in size for 28-5=23 AWG wire...

Promote Your Company on RF Cafe

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 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.

Sunday the 4th

EE Theme Crossword for September 4th

Electrical Engineering Theme Crossword Puzzle for September 4th, 2022 - RF CafeThis week's crossword puzzle for September 4th sports an electrical engineering theme. 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!

Many Thanks to Withwave for Long−Time Support!

Withwave RF & Microwave Components - RF CafeWithwave manufactures an extensive line of metrology quality coaxial test cable assemblies, connectors (wave-, end-, vertical-launch, board edge, panel mount), calibration kits (SOLT), a fully automated 4-port vector network analyzer (VNA) calibrator, between- and in-series connector adaptors, attenuators, terminations, DC blocks, torque wrenches, test probes & probe positioner. Special test fixtures for calibration and multicoax cable assemblies. Frequency ranges from DC through 110 GHz. Please contact Withwave today to see how they can help your project succeed.

Friday the 2nd

Coax vs. Twinlead

Coax vs Twinlead, July 1965 Electronics World - RF CafeThe debate regarding the superiority of coaxial cable and twin-lead cable, aside from personal preferences, comes down to this: Twin-lead cable has lower loss but is vulnerable to extraneous signal pick-up and is sensitive to nearby objects in the routing path from antenna to receiver; it is also inexpensive. Coaxial cable has higher loss and is more expensive, but is significantly less sensitive to the routing path and external signal interference. In strong signal areas and/or for short runs, higher loss in coax is not an issue, and its higher cost can usually be justified for the near immunity from interference advantage. In areas where the signal at the antenna is weak and the path length to the receiver is long, twin-lead, aside from its lower cost, helps yield a better signal. The same pros and cons apply for the other direction with a signal going from a transmitter to an antenna, but this 1965 Electronics World magazine article is addressing television and radio reception...

"Plug-In" RF Cable Assemblies for D38999 & VITA67

"Plug-in" RF Cable Assemblies for D38999 & VITA67 - RF CafeConductRF knows many times you want to just buy your RF assemblies to plug in to your circular D38999 connector or your VITA67 module. We offer multiple solutions for both styles of multi-port connector all available on short lead times based on our on hand materials stock. D38999 integrates BMA, SMPM & SMPS connectors, also other #8, #12 & #16 coax contact solutions. VITA67.1/2 uses SMPM solutions, but the new VITA67.3 also offers SMPS and NanoRF to support your coax. These are 100% factory tested to exacting VSWR and loss standards because we know, Results Count!

E, I, R, and P Chart

E, I, R, and P Chart, December 1954 Popular Electronics - RF CafeMaybe given the nature of the newly introduced Popular Electronics magazine (this was only the third issue), the editors decided using a big word like "nomograph" might be a little too out of the realm for use in a magazine seeking to appeal to newcomers to the electronics field. It is a little surprising since students of the day were quite accustomed to using this type of a graph since computers still filled entire rooms and hand-held calculators went by a different name - slide rules. In fact, because of a familiarity with using a slide rule, people were more accustomed to having to shift decimal points to the left or right first to do the calculation on a device that only displayed values in a single decade range, and then to arrive at the final answer after the calculation. That is exactly the skill needed to use the nomograph. I guess that people today - even engineers - would have a harder time keeping track of powers of 10 than...

Exodus 18.0-26.5 GHz, 200 W SSPA

Exodus AMP4065B−LC 18.0-26.5 GHz, 200-Watt SSPA - RF CafeExodus Advanced Communications is a multinational RF communication equipment and engineering service company serving both commercial and government entities and their affiliates worldwide. We are pleased to present the new Exodus Model AMP4065B−LC, 18.0-26.5 GHz, 200 W Solid State Amplifier - another industry first from Exodus. Designed for High Field Level EMC Testing, Mil−Std 461(RS103) standards as well as other High-Power Applications. Exodus Model AMP4065B−LC is a 12U design providing outstanding power/gain flatness, Forward/Reflected power monitoring in both dBm & Watts, VSWR, voltage/current and temperature sensing for superb reliability and ruggedness. Unprecedented reliability compared to TWT's, 53 dB gain including gain control, and −20 dBc harmonics. 10 W, 20 W, 40 W, 60 W & 100 W versions available...

Doppler Radar Charts the Airlanes

Doppler Radar Charts the Airlanes, May 1959 Popular Electronics - RF CafeDoppler radar is familiar to most people these days mainly because of the weather reports available online and on television reports. Not many actually understand the principle behind it, though. A handful can tell you that in sound form it is the frequency shift phenomenon that occurs when a train goes by while blowing its horn. Almost none could say why or how it is useful in detecting storm systems or for tracking aircraft. This 1959 Popular Electronics magazine article attempts to explain Doppler radar to the uninitiated. Having worked as an air traffic control radar technician in the USAF, and then having done the RF and analog system circuit design for a prototype Doppler weather radar as an engineer, I have had a lot of exposure, but I am by no means an expert...

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 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.

Thursday the 1st

Bell Telephone Labs - Type-O Open Site Systems

Bell Telephone Laboratories - Type-O Open Site Systems, October 1952 Radio-Electronics - RF CafeAlways creating and pushing the leading edge of communications technology, Bell Telephone Systems and their research group, Bell Telephone Laboratories, frequently ran full-page promotions in many types of magazines, from electronics industry publications like the 1952 issue of Radio-Electronics, to domestic rags like Woman's Day and Better Homes and Gardens. In this instance, Bell Labs was justifying its continued use of the original open-wire telephone line distribution systems using poles with individual pairs rather than the newer multi-pair cables that carried sometimes hundreds of circuits in the space of a few square inches of cross-section, and in a protective sheath that guarded against signal interference and weather degradation. An entire volume of the Bell System Technical Journal (BSTJ) was published on the Type−O (open wire) Carrier System in the same year this ad appeared. It basically came down to economics based on the fact that so many thousands of miles of the old lines in existence performed adequately well, and new technology allowed two or more circuits to co-exist on the same twisted pair...

QSL from Sputnik

QSL from Sputnik, November 1958 Popular Electronics - RF CafeSecuring confirmation of having made a contact (QSL in ham-speak) with a radio operator behind the communist Iron Curtain was a real achievement during most of the 20th century. Russian and Chinese citizens were routinely imprisoned for such activity, and if you did manage to elicit a response to your CQ (request for contact), there was a good chance it was with a government propagandist posing as a civilian. When Sputnik 1 was put in orbit on October 4, 1957, a whole new realm of DXing (long distance communication) opened up by providing satellite relay paths. Sputnik 1, the world's first artificial satellite, broadcast a series of pulses at 20.005 and 40.002 MHz that were tracked and reported by both professional and amateur radio operators. Vital data was learned based on the time and strength of signals that allowed scientists to ascertain the physics of upper atmosphere characteristics...

Skyworks Advanced Synchronization for Next-Gen 5G Deployments

Skyworks Advanced Synchronization Solutions Support Next-Generation 5G Deployments - RF CafeSkyworks Skyworks Solutions today announced the launch of its new portfolio of network synchronization solutions, which includes the Si551x and Si540x families of NetSync™ clock integrated circuit devices and Skyworks' AccuTime™ IEEE 1588 software. Each product family is engineered to meet the requirements of mobile operators and equipment vendors for 5G fronthaul networks. Precise and accurate time synchronization is critical to ultra-reliable network operation and is paving the way for future enhancements, including Ultra-Reliable Low-Latency Communications (URLLC) and Coordinated Multipoint Access (CoMP) that empower 5G to support autonomous vehicles, factory automation, telemedicine and other emerging applications. "Skyworks' decades of expertise and patented timing technology enable the company to offer best-in-class performance, integration and reliability, featuring its ultra-low jitter DSPLL® architecture with MultiSynth™ 'any-frequency' clock synthesis...

Crosley Model 555 Schematic

Crosley Model 555 (A.F.M.) 5-Tube 2-Band Superhet. Radio Service Data Sheet, March 1936 Radio-Craft - RF CafeThis is another Radio Service Data Sheet that appeared in the March 1936 edition of Radio-Craft magazine. I post this schematic and functional description of the Crosley Model 555 (A.F.M.) 5-Tube 2-Band Superhet radio manufacturers' publications for the benefit of hobbyists and archivists who might be searching for such information either in a effort to restore a radio to working condition, or to collect archival information. As mentioned previously, manufacturers usually did not provide this data to anyone other than an authorized service shop, so making it available via the magazine was a huge benefit to repair shops and do-it-yourselfers. Unfortunately, not very much textual content was included with the schematic. It was part of a group of seven different models (see table of contents), and not much more than the schematic was provided for each...

Transistor Topics

Transistor Topics, February 1960 Popular Electronics - RF Cafe"Transistor Topics" was a monthly column in Popular Electronics magazine that helped introduce and educate readers to/on the relatively new topic of transistor design and troubleshooting. Transistors were first invented in December of 1948, but it took about a decade before they were reliable and inexpensive enough to be integrated into a large variety of products - and affordable to the hobbyist. Editor Lou Garner often presented questions from readers and answered in layman's terms. This month's question came from a reader in Bogota, Columbia, which in 1960, was a big deal. Nowadays we take for granted how small the world is due to the Internet. Aldens department store is mentioned, which I remember moving into a shopping plaza next to Hechinger lumberyard and home center in Annapolis, Maryland, sometime around 1970...

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 Visit Empower RF's Website 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.

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.

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Temwell Filters
Axiom Test Equipment - RF Cafe

Windfreak Technologies Frequency Synthesizers - RF Cafe

Rigol DHO1000 Oscilloscope - RF Cafe