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Homepage Archive - October 2022 (page 3)

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

Friday the 21st

Mac's Service Shop: Voltage-Regulating Transformers

Mac's Service Shop: Voltage-Regulating Transformers, July 1965 Electronics World - RF CafeDespite having heard of and used the "voltage-regulating transformer" (aka "constant voltage transformer," CVT), I never knew exactly how they work. This installment of Mac's Service Shop in the July 1965 issue of Electronics World magazine happens to address the device, so now I at least have some idea what's going on to magically hold the secondary voltage at an amazingly constant value regardless (within reason) of the primary voltage. It is a purely passive device that uses ferroresonance for feedback. The price to be paid for such a convenience is explained to Barney by Mac after Barney gets befuddling readings on his voltmeters. Mac invokes the name of the inventor, Joseph Sola, who manufactured CVT's in the Sola Electrics Company premises. According to the SolaHD (merger of Sola and Hevi-Duty) About Us webpage, "Sola Electric opened in 1930 as an emerging laboratory in two modest size rooms in a Chicago bank building. It was a small beginning, but Joseph G. Sola had big ideas. Beginning in the 1930's, he practically invented the field of transformer magnetics...

Lynk Launching World's 1st 5G Space Platform

Lynk Launching World's 1st 5G Space Platform - RF Cafe"Lynk Global, the world's leading satellite-direct-to-standard-phone telecoms company, will launch the world's first 5G cellular base station in space in a first-of-its-kind demonstration. This test will demonstrate the ability to send a 5G signal from space to standard mobile devices on Earth. The test has been funded by an undisclosed partner. Lynk is the only company in the world to demonstrate satellite-direct-to-standard-mobile-phone technology. Earlier this September, Lynk received the world's first satellite-direct-to-phone commercial license from the Federal Communications Commission (FCC). Lynk has also patented the ability to connect to existing standard 5G devices on Earth w/no change to existing..."

How Magnetic Tape Is Made

How Magnetic Tape Is Made, February 1955 Popular Electronics - RF CafeMagnetic tape was the recording medium de rigueur for more than half a century, after the era of wax and wire and before the era of magnetic and optical disks. In fact, magnetic tape is still the storage medium of choice when analog signals must be stored without first being digitized. Magnetic data storage media each has its own characteristic lifetime because of factors like the initial quality of the magnetic domains, the dimensional stability of the substrate, and susceptibility to outside influences. Just as vinyl records and other vintage technologies have been experiencing a comeback with both young and old alike, Kodak recently announced it is ramping up in Rochester, NY, for higher production volumes of its 35 mm film due to increasing demand. I wonder if home film processing equipment is resurging, too...

Lotus Ultra-Flat Gain Low Noise Amplifier

Lotus Communication Systems New High Performance, Ultra-Flat Gain Low Noise Amplifier - RF CafeLotus Communication Systems, a manufacturer of connectorized, cascadable RF and microwave components, has developed a new high performance, ultra-flat gain low noise amplifier (LNA), PN#: LADC8GFR. This LNA have low noise figure 1.8 dB and ultra-flat gain ±0.5 dB over wide frequency range from DC to 8 GHz. EMI Shielding (includes weatherproof) option is available for all our LNAs. Lotus' LNA can be customized to add integrated Bias Tee, wide voltage operation (+6 ~ +34 V), integrated RF limiter, multi-stage high gain, and meet customer's mechanical requirement. Lotus Communication Systems, Inc. has CNC machine shop in house with 4th axis Robodrill for RF enclosure manufacturing. Lotus also has state-of-art SMT line in house that use automatic stencil printer, automatic pick and place and reflow oven...

RCA Test Equipment Advertisement

RCA Test Equipment Advertisement, November 1963 Popular Electronics - RF CafeI have to admit to not remembering (or ever knowing) that Radio Corporation of America (RCA) manufactured electrical test equipment, so seeing this full-page advertisement in a 1963 edition of Popular Electronics magazine was a surprise. RCA made a few types of analog multimeter kits, some project and experimenter kits, and even an oscilloscope kit. A little more thumbing through other Popular Electronics magazine editions revealed the RCA Institutes, which was a mail order electronics training program similar to the ITT Institute and National Radio Institute (NRI, from whom I took a course many moons ago). Knowing that if you wait long enough, just about everything shows up on eBay, I did a quick check and found a few vintage RCA Institutes items, including an RCA Institutes Ham Radio Signal Generator Kit...

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 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.

Thursday the 20th

National Radio Institute (NRI)

National Radio Institute (NRI), December 1954 Radio News - RF CafeLearn-at-Home correspondence courses for a career in electronics maintenance and repair was a big deal throughout most of the last century. Similar training was offered by many other trades, such as automobile / aircraft engine repair, plumbing, HVAC, electrical wiring / control / motors, small appliance repair, watch / clock repair, etc. Many moons ago (c.1985) I took an electronics course from National Radio Institute. It included a few pieces of test equipment which required building and aligning, including a digital multimeter, signal generator, and a 10 MHz bandwidth oscilloscope. I still have many of the electronic components - lights, inductors, switches, transistors, ICs, diodes, capacitors, solderless breadboard, terminal strips - that came with it for experimentation. This particular course in the December 1954 issue of Radio News magazine offered instruction in television repair...

See How Modelithics Is Making Waves Lately

See How Modelithics Is Making Waves Lately - RF CafeModelithics, the industry leader in providing innovative and high-quality custom modeling and measurement services for RF, microwave and millimeter-wave electronic devices provides this update on the latest happenings with their products and industry partners. Modelithics® Releases the COMPLETE+3D Library™ v22.4 for Ansys® HFSS™ Included in this library are over 370 highly scalable Microwave Global Models™ for capacitor, inductor, and resistor families from many popular vendors. Also included is Modelithics' collection of over 500 3D electromagnetic (EM) geometry models for inductors, capacitors, filters, packages, and connectors. With both circuit and 3D EM models, the Modelithics COMPLETE+3D Library now includes over 30 vendors for more than 850 models representing over 25,000 individual components. Modelithics Offers New Attenuator and Resistor Models from Smiths Interconnect...

Arvin Models 150TC, 151TC Schematic & Parts List

Arvin Models 150TC, 151TC Schematic & Parts List, December 1947 Radio News - RF CafeThere are still many old-timers and beginning nostalgic collectors out there who nurse heirloom and otherwise procured vacuum tube radios - like this Arvin Models 150TC, 151TC combination radio / phonograph - back to health (operating condition) and/or keep them in good health. While it is possible to purchase schematics, parts lists, and service instructions from many different models, there are still some that have escaped the scanners of those publishers. For those kindred spirits in search of such reference materials, I happily scan, clean up as necessary, and post this collection (see complete list at bottom of page). I have dozens more that will eventually be added over time, so check back later or send me an e-mail if I have an issue (check the lists first, please) of Radio News, Radio-Craft, etc. known to contain the information you need...

2022 ARRL Online Auction Begins October 20th

2022 ARRL Online Auction Begins October 20th - RF CafeIt's time! The 2022 ARRL Online Auction  begins Friday, October 21st and runs through the 27th. A preview is available right now. As of this post, there are 123 items to bid on including Ham Radio transceivers, books, apparel, vintage QST magazines, test equipment, and accessories. "Proceeds from our yearly Online Auction go directly to ARRL's education programs, including promoting activities to license new hams, strengthening Amateur Radio's emergency service training, offering continuing technical and operating education, and creating instructional materials." Please contact immediately the ARRL if you have items for donation...

Sonnet of a Ham

Sonnet of a Ham, October 1947 QST - RF CafeI have never been a fan of "free verse" poetry,

be it in the form of a sonnet or otherwise.

In my humble opinion,

poems that do not both rhyme

 and have some measure of meter

 represent laziness on the part of the "poet."

Without requiring poetry to rhyme,

all that is required to declare anything a poem

is to break the writing into poem-like lines,

et voilà - you have a poem.

It is like slinging a brush-load of paint

onto a canvas and calling it art.

Example -- I hereby proclaim the above to be a poem because I broke it into separate lines - see what I mean? That ain't no poem; we both know it.

I will excuse the following example since it was written by a Ham about Amateur Radio - although most of its lines do actually rhyme...

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 IPP for 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. 

Wednesday the 19th

Electronics-Themed Comics

Electronics-Themed Comics, October 1952 Radio-Electronics - RF CafeHere is a great collection of electronics-themed comics from the October 1952 issue of Radio-Electronics magazine. My favorite is the one on page 100 where the radio repair shop mocks the next-door pharmacy's promotion of a self-repair manual. The page 144 comic is another play on the theme that casts aspersions on the do-it-yourself electronics repairmen of the day. Many self-help books were written purporting to make repairing a radio or television a simple task, while convincing people that repair shops were just out to cheat them. I have posted many comics illustrating the folly of such endeavors. Two of the comics are ham radio related, and the other (a total of seven!) is a self-deprecating shot at a hobbyist building a circuit of some sort...

Politically Sensitive History of Semi Industry

Politically Sensitive History of Semiconductor Industry - RF Cafe"Semiconductors - the digital machinery that runs smartphones and computers, and helps run everything from cars and doorbells to water and power supplies and military systems - are ubiquitous. Also called chips or integrated circuits, they are usually pieces of silicon with transistors etched in them - transistors keep track of the 1s and 0s that run all digital systems. Back in the late 1950s, getting four transistors to work on a small piece of silicon was a big accomplishment. The latest iPhone14's processor has 16 billion transistors. While the U.S. has led the development of chips, most are now fabricated outside the country. Taiwan and South Korea have cornered the market on building the most advanced chips - though the U.S. and China are trying to change that. Having the world's leading makers in political hotspots is a concern, too..."

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.

Hetrofil - An Aid to Selectivity

Hetrofil - An Aid to Selectivity, September 1939 QST - RF CafeThis "Hetrofil," (sometimes errantly referred to as a "Heterofil") shorthand for "heterodyne filter," was conceived of, designed, and built by author Raymond Woodard. A Wien bridge is used to selectively null out interference caused by leakage of the heterodyne beat frequency into the audio (phone) circuit. The beauty of the Hetrofil is only a few inexpensive passive components are needed. It is inserted between the receiver headset jack and the headset. A couple years later, Wade Caywood applied the Hetrofil concept to an oscillator tuning and stabilization circuit (see "An Amateur Application of the Wien Bridge," January 1941 QST. Also, a form of the Hetrofil was used in Hewlett-Packard's Model 200A audio generator...

ConductRF Hi-Frequency Flexible RF Cable Assemblies

ConductRF Hi-Frequency Flexible RF Cable Assemblies October 18, 2022 - RF CafeConductRF's latest innovation is Hi-Frequency RF Jumper Cables with 2.92 mm, 2.4 mm or 1.85 mm connectors as standard. This assemblies use our optimized direct solder attached connectors and our superior double shielded hi-frequency A61SW flexible cable with shielding effectiveness greater than -100 dB. These cables are design to support the latest requirements for 5G applications for cross connecting modules, but can equally be used in any field where hi-frequency jumper cables are required. Beyond our standard interconnect, we can also offer solutions with SMP, SMPM, SMA and many other common connector interfaces. Hi-Performance right angled options are available utilizing hard setting shrink tube to form the cable bend...

One Receiver, All Bands

One Receiver, All Bands January 1963 Popular Electronics - RF CafeRF Cafe visitor David M. wrote to ask that I scan and post this article from the January 1963 edition of Popular Electronics magazine. It is written by Philip Hatfield, of the Receiving Tube Department of General Electric, describing a very simple design that uses a "Compactron" vacuum tube, which consist of two triodes and a pentode. The Compactron was a vacuum tube version of the multi-amplifier integrated circuit of today, only without the peripheral passive biasing and coupling components. Plug-in coils (inductors) for quick and easy frequency band changes are the key feature here. RCA 6AF11 Compactron vacuum tubes are still sometimes available for purchase on eBay for $10-$40 bucks each...

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 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.

Tuesday the 18th

Infrared Electronics

Infrared Electronics, February 1961 Popular Electronics - RF CafeIt was 1958, over the Taiwan Strait, when the first Sidewinder air-to-air missile flew up the tailpipe of a MIG-17 Fresco after being launched by an F-104 Starfighter. The age of offensive infrared (IR) warfare had begun. It is amazing that the detection and guidance system for the Sidewinder was built largely from discrete components, without the advantage of large scale integration. IR night vision devices were actually used by the military as early as WWII with the renowned Snooperscope (handheld) and the Sniperscope (mounted to a carbine rifle). Both required an infrared light source to illuminate the target. Today's night vision goggles and scopes are sensitive enough to be totally passive. This "Infrared" article from the February 1961 issue of Popular Electronics magazine talks about early developments in infrared technology. Corny-looking prototypes of IR wireless phones are shown, but obviously...

Electronics Fundamentals, USAF Air University

Electronics Fundamentals, USAF Air University - RF CafeThis "Electronics Fundamentals" material is from the U.S. Air Force's Air University collection of tutorials (Course 3050, dated 1960). It was found in a bin at Goodwill, bound along with a few other sections by the Extension Course Institute including Introduction to Radar and Television Principles. A few days ago I posted the Introduction to Radar section. A very thorough introduction to electric principle is presented, and is as useful as any modern text on the subject. Note in figure 21 that current flow (electron flow, or EF) is depicted as going from negative to positive, which is the correct physical model. Prior to World War II, current flow was considered to be from positive to negative; that scheme is now called conventional current flow (CCF). At semiconductor boundaries there is a sort of flow from positive to negative called "hole" current. A "hole" is the absence of an electron in an atom's valence bands...

R&S: A Revolution in Beyond-Line-of-Sight Communications

Rohde & Schwarz: A Revolution in Beyond-Line-of-Sight Communications - RF CafeAt Euronaval 2022, taking place from October 18 to 21 in Paris, France, Rohde & Schwarz is proud to announce the launch of its new liquid-cooled R&S SK4105/4110 HF high-power transmitters. With this, the company is offering next generation technologies in beyond-line-of-sight (BLOS) communications. Over the past decades, Rohde & Schwarz has been a reliable innovator in HF technology. This new transmitter offers extreme reliability, best-in-class availability and low total cost of ownership. The company's high vertical integration ensures service and maintenance for the entire lifecycle. Unsurpassed performance through HF wideband capability as well as 5 kW or 10 kW output power make the R&S SK4105/4110 unique on the market...

Oscilloscope Traces

Oscilloscope Traces, November 1957 Popular Electronics - RF CafeThis is one of a multi-part series of articles that appeared in Popular Electronics magazine on using an oscilloscope (o-scope) to analyze signal waveforms. An introduction to square waves and how to accurately measure them is covered here. Frequency-compensating the o-scope probe is always an important step prior to sampling just about any waveform other than a pure sinewave, because per Fourier series analysis, every periodic waveform can be defined by a series of sinewave and various frequencies, phases, and amplitudes. The author demonstrates with a square wave being composed of the fundamental frequency and its odd harmonics. I remember being amazed to learn whilst in engineering school that mathematically it takes a summation of an infinite number of odd harmonics (appropriately amplitude-adjusted) to define a pure square wave (the Gibbs phenomenon)...

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.

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.

Monday the 17th

Electronic Counter Tube

Electronic Counter Tube, March 1956 Radio-Electronics - RF CafeIf you look up "bit" on Wikipedia, is claims the word is a portmanteau of binary + digit, but according to the "Electronic Counter Tube" article in the March 1956 issue of Radio-Electronics magazine, it comes from binary + unit. The cited reference is a 1980 book. That's a minor point, but I wonder if the belief has changed over time. Going further down the metaphorical rabbit hole, per the same source, "The term byte was coined by Werner Buchholz in June 1956, during the early design phase for the IBM Stretch computer." Now, back to the topic at hand. The E1T "Decade Counter Tube" was produced by Mullard, located in the UK. It had an ingenious design which directed an internal electron beam onto fluorescent numerical segments according to the number of pulses supplied to the increment grid (D1 in Fig. 1). A holding voltage...

Test Instruments Part 6: The VTVM

Test Instruments Part 6: The Vacuum Tube Voltmeter, July 1959 Popular Electronics - RF CafePrior to the advent of FET-input digital multimeters (DMMs), the vacuum tube voltmeter (VTVM) was the primary instrument for use when high input impedance was required. For the newcomer to electrical measurements, high input impedance for the measuring instrument is needed when measuring high impedance circuits so as not to load down the circuit under test and cause an erroneous result. For instance, suppose you are trying to measure the voltage across a 100 kΩ resistor that is in series with a 50 kΩ and your voltmeter has a 100 kΩ input impedance. The parallel combination of the two 100 kΩ resistances (resistor and voltmeter) is 50 kΩ. If the supply voltage is 3 volts, the voltage across the 100 kΩ resistor would actually be 2 volts, but with the voltmeter across it, the reading would be 1.5 volts. If the input impedance of the voltmeter was 10 MΩ instead, the parallel resistance across the 100 kΩ resistor would be about 99 kΩ, which would only introduce a very small error...

Disposable Electronics on Sheet of Paper

Disposable Electronics on Sheet of Paper - RF Cafe"Discarded electronic devices, such as cell phones, are a fast-growing source of waste. One way to mitigate the problem could be to use components that are made with renewable resources and that are easy to dispose of responsibly. Now, researchers reporting in ACS Applied Materials & Interfaces have created a prototype circuit board that is made of a sheet paper with fully integrated electrical components, and that can be burned or left to degrade. Most small electronic devices contain circuit boards that are made from glass fibers, resins and metal wiring. These boards are not easy to recycle and are relatively bulky, making them undesirable for use in point-of-care medical devices, environmental monitors or personal wearable devices. One alternative is to use paper-based circuit boards, which should be easier to dispose of, less expensive and more flexible..."

GE Model 250 Radio Service Data Sheet

GE Model 250 Radio Service Data Sheet, August 1946 Radio-Craft - RF CafeThe General Electric (GE) Model 250 portable radio was considered a "suitcase" style because it looked kind of like - guess what? - a suitcase. It ran on either 120 volts AC or an internal 2.1 volt battery. A charging circuit was provided for the battery, which was a nice feature so the owner didn't have to keep buying new batteries. Fortunately, there seems to be many of these GE 250 radios available in various states of reconditioning. eBay* currently has four listed ranging in price from $40 to $150. One listing has very nice photos of the internal workings and of the Willard model RADIO-25-2 wet storage cell battery (see below, right). Click on the thumbnails for larger images. The nomenclature label for the radio is fully legible. This Radio Service Data Sheet for the GE 250 radio appeared in the August 1946 issue of Radio-Craft magazine...

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.

Thanks to Anritsu for Their Support!

Anritsu (electronics test equipment)Anritsu 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.

Sunday the 16th

Electrical Engineering Theme Crossword for October 16th

Electrical Engineering Theme Crossword Puzzle for October 16th, 2022 - RF CafeThis custom-made Electrical Engineering-themed crossword puzzle for October 16th, 2022, is brought to you by RF Cafe. 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 puzzle 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 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."

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Windfreak Technologies Frequency Synthesizers - RF Cafe
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Copper Mountain Technologies (VNA) - RF Cafe