Homepage Archive - June 2019 (page 2)

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Friday 14

Destiny and Geomagnetism

Destiny and Geomagnetism, July 1971 Popular Electronics - RF CafeIf you read the physics and geographic news of the day, most likely you have seen articles on the rapidly increasing migration rate of the geomagnetic "north pole" over the past few decades. Magnetic north has never exactly lined up with geometric north (as borne out in geological samples of rocks), and neither has it ever been uniformly distributed across the globe. Ancient explorers on terra firma and at sea knew that a magnetic compass needle did not align with the same stars, moon, or sun position for every location, after accounting for difference in longitude. That is because the earth's magnetic field is very nonuniform in strength and does not follow straight lines from pole to pole as they more generally do from outer space. A correction factor must be applied to any magnetic north indication based ...

ConductRF Rugged Replacement VNA Cables to 70 GHz

ConductRF Rugged Replacement VNA Cables - RF CafeConductRF, a premier manufacturer of standard and custom RF cable assemblies, announces the availability of Precision Ruggedized VNA Cables from ConductRF offer RF Engineers great alternatives to costly OEM cables that are now past their best days. We have standards for applications at 18 GHz, 27 GHz, 40 GHz, 50 GHz & 70 GHz. Our torque resistant connector heads and phase stable constructions ensure great performance for many tests to come. VNA Series cables are enhanced with a stainless steel spiral armor, providing protection from excess bending and crushing forces. A black non-conductive outer cover completes the product. These cables are phase stable during flexing and have an operating life cycle of up to 5,000 matings ...

The Iconoscope

The Iconoscope, July 1944 QST - RF CafeAn iconoscope was an early form of television image capturing tube. Some amateur radio operators were experimenting with slow scan TV even back when the technology was relatively new to the world. When this article was written in 1944, there were still large portions of the United States that did not have television broadcast coverage. Of course I would argue that at the time of my growing up in the 1960s and early 1970s a lot of areas - even suburbs - were still not covered by TV signals, based on how cruddy the reception at my parents' house was. But I digress. The article mentions that because of the lack of TV coverage, many amateurs did not even have television receivers (TV sets) in their homes to use along with experimental television transmitters ...

Cobham Antenna Systems Publishes Its 1st Newsletter

CAS News from Cobham Antenna Systems - RF Cafe"Welcome to the first issue of CAS News from Cobham Antenna Systems! Inspired by the richness of late-spring, we decided to launch this bi-monthly newsletter, to help keep everyone informed of all the exciting developments going on here at Cobham Antenna Systems (CAS), in Newmarket, UK. In this issue, the first of many to come, we cover our presence at two recent key industry exhibitions: AUVSI / Xponential 2019 in Chicago, USA, and EW-E 2019 in Stockholm, Sweden. At these shows we introduced a new antenna that is designed specifically for C-UAS (that is, Counter-Unmanned Airborne Systems). We also take a look at how we are helping Professor Alan Wilson ...

Organic Laser Diodes Within Reach

Organic Laser Diodes Within Reach - RF Cafe"Researchers from Kyushu University, Japan, have demonstrated lasing from an electrically driven organic diode. Reporting their findings in the journal Applied Physics Express under the title 'Indication of current-injection lasing from an organic semiconductor,' the researchers circumvented the traditional issues of organic materials (which due to their inherent resistance, tend to break down under the high currents required for lasing). A critical step in lasing is the injection of a large amount of electrical current into the organic layers to achieve a condition called population inversion ..."

Nova Microwave: RF & Microwave Circulators & Isolators

Nova Microwave circulators & isolatorsNova Microwave is a leader in technically differentiated electronic and radio frequency Ferrite Circulators and Isolators that connect, protect and control critical commercial and military wireless telecommunications systems. Our staff is dedicated to research and development of standard and custom design quality Ferrite Circulators and Isolators from 380 MHz to 26.5 GHz. Please visit Nova Microwave today.

 

Thursday 13

Motorola PNP & NPN Oxide-Passivated Silicon Annular Transistors

Motorola PNP & NPN Oxide-Passivated Silicon Annular Transistors, May 4, 1964 Electronics Magazine - RF CafeEverything is relative... just ask Albert Einstein. The use of terms like "contemporary," "modern," etc., in the titles of books has always annoyed me. They would be okay if the titles also included the year or at least the decade to which the claim applies. Not quite as nefarious is the claim of "high frequency" when describing electronics components since it is safe to assume that most readers understand the era to which it applies. To a lesser extent that goes for "high voltage" and "high current." This 1964 advertisement for Motorola's Oxide-Passivated Silicon Annular Transistors appeared in Electronics magazine touting the high frequency capability ...

Notable Quote by Neil Armstrong

Notable Quote by Neil Armstrong - RF CafeAs we approach the 50th anniversary of the Apollo 11 moon landing, many magazines are publishing articles about the event and the background leading up to it. I have tagged a couple notable quotes from astronauts involved that will be posted over the next month or so. The June issue of Discover magazine included this one as delivered by Neil Armstrong to the National Press Club: "I am, and ever will be, a white-socks, pocket-protector, nerdy engineer, born under the second law of thermodynamics, steeped in the steam tables, in love with free-body diagrams. ... Science is about what is. Engineering is about what can be." Amen, bro.

Custom MMIC Intros 18 to 40 GHz K-, Ka-Band LNA

Custom MMIC Intros 18 to 40 GHz K-, Ka-Band LNAThe CMD299 is a highly efficient GaAs MMIC low noise amplifier ideally suited for EW and communications systems where small size and low power consumption are needed. The device is optimized for 30 GHz and delivers greater than 17 dB of gain with a corresponding noise figure of 3.5 dB and output 1 dB compression point of +7 dBm. The CMD299 is a 50 ohm matched design which eliminates the need for external DC blocks and RF port matching. The CMD299 offers full passivation for increased reliability and moisture protection ...

3D Smith Chart High Frequency Circuit Design

3D Smith Chart High Frequency Circuit Design (PRIME 2019) - RF CafeAndrei Muller, of the Swiss Federal Institute of Technology in Lausanne will present his 3D Smith Chart software during the PRIME 2019 event on Monday, July 15th. The talk will start by presenting the mathematics behind the Smith chart and extended 2D Smith chart from the group theory of geometry point of view (Kleinian view of geometry). Using the Maxime Bochert-Klein results on Mobius transformations (among which the Smith chart constitutive equation belongs). The introduction will show what happens by applying the voltage reflection coefficient transformation and power wave reflection coefficient transformation on the grid of the impedance plane, random geometrical objects and photos. The geometry of these mappings will be then compared with the geometry of other scattering parameters mappings when applied to the same objects ...

2D Materials Show Promise for Future Electronic Devices

2D Materials Show Promise for Future Electronic Devices - RF Cafe"A new method to develop 2D materials, called transition metal dichalcogenides, paves the way for novel applications in optoelectronics and other next-generation electronic devices. The promise of 2D graphene material for next-generation electronics is well-known - because of its high conductivity and light weight. However, there are many other 2D materials that also can be used in future electronics applications to bring new and improved characteristics. Some of the materials in which researchers are particularly interested are a group of semiconductors called transition metal dichalcogenides, or TMDs. These materials, a few atoms thick ..."

PCB Directory: Printed Circuit Board Fabrication & Assembly

PCB  Directory - RF Cafe

PCB 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 (e.g., material, flexible, rigid), Geographical location, and more.

Wednesday 12

Sentinel Model 217-P Portable Radio Set Radio Service Data Sheet

Sentinel Model 217-P Portable Radio Set Radio Service Data Sheet, August 1940 Radio-Craft - RF CafeMany months have passed since I last posted one of the Radio Service Data Sheets for vintage radio sets. This one for the Sentinel Model 217−P portable appeared in the August 1940 issue of Radio−Craft magazine. Hobbyists and professional electronics service shops relied on these back in the day because obtaining the information from manufacturers could be difficult or even impossible. Some companies would not provide service information for alignment and troubleshooting to businesses that were not officially endorsed to do so. That left some of the smaller shops and most do-it-yourselfers without a means to work on sets. Once places like SAMS Photofacts came along with information packets that could be purchased ...

Carl & Jerry: Abetting or Not?

Carl & Jerry: Abetting or Not?, October 1956 Popular Electronics - RF CafeCarl and Jerry found the appearance and construction of 2,400 megacycle transmitters and receivers to be quite odd compared to the equipment they were used to dealing with. It's sometimes hard to believe such an attitude of wonder when our world today is utterly filled with wireless devices operating in the 2.4 GHz ISM band. Author John T. Frye could never have imagined that such a reality would would exist half a century after his story of the pair of teenage electronics sleuths. Unlike our postage stamp size integrated assemblies that cost a few dollars, they speak of "special ultra-high-frequency 'light-house' tubes with a cavity resonator clamped on top of them." Back to the story, though... Did you know that police were using radar guns as far back as 1963? ...

Women in Engineering Scholarship Podcast

Women in Engineering Scholarship Podcast (IMS 2019) - RF CafeListen in on our latest news as our very own CEO Paul Blount proudly presents Custom MMIC's Women in Engineering scholarship last Wednesday, June 5th 2019 at the International Microwave Symposium in Boston. In this quick podcast, meet the first three recipients of the scholarship: Sarah McKinley, Emma Fournier and Grace Remillard. Blount describes each of the women as "so talented."

Mechanical Engineering Salaries State by State

Mechanical Engineering Salaries State by State - RF CafeThis latest report by the Interesting Engineering website lists a state-by-state accounting of mechanical engineers' salaries. Data was assimilated from the U.S. Bureau of Labor Statistics (BLS). The Bureau projects a 9% job growth rate form 2016 to 2026. The average salary went from $90,340 in 2017 per year to $92,800 in 2018, which represents a 2.7% increase. That is just about on par with the 2-3% inflation number claimed by the BLS. The value of benefits is not included. Alaska had the highest average pay at $128,69, while Arkansas came in last with $71,730. On a side note, I've always been critical of multistate companies having different pay scales for people doing the same jobs at various locations. Sure, cost of living differs, but ultimately they are paying employees unequally from a corporate accounting perspective.

China to Launch New Amateur Satellite with 'Sail Ball' Stabilization

China to Launch New Amateur Satellite with 'Sail Ball' Stabilization - RF Cafe"Chinese Amateur Satellite Group (CAMSAT) has announced the impending launch of the CAS-7B satellite, also designated as BP-1B, a short-lived spacecraft that will carry an Amateur Radio payload. An unusual feature of the spacecraft is its 'sail ball' passive stabilization system. The 1.5-U CubeSat is attached to a 500-millimeter flexible film ball - or sail - that will offer passive 'pneumatic resistance' stabilization. CAS-7B is expected to remain in orbit for up to 1 month. The spacecraft will carry an Amateur Radio transponder and educational mission. CAMSAT is working with Beijing Institute of Technology (BIT), a top aerospace school ..."

Empower RF Systems: RF & Microwave Power Amplifiers

Empower RF SystemsEmpower 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.

Tuesday 11

Lesson from Europe

Lesson from Europe - Editorial, May 4, 1964 Electronics Magazine - RF CafeIn the light of having just marked the 75th anniversary of the D-Day (Operation Overlord, June 6, 1944), which marked the beginning of the end of Hitler's ruthless siege on all of Europe, please note how Electronics magazine editor Lewis Young cites, in 1964, the continued rebuilding of Europe as the reason many - maybe most - companies there are still, two decades later, concentrating engineering and financial resources on getting back on a solid footing rather than chasing after the latest and greatest in nonessential technologies. It was probably an accurate assessment of the situation. However, I do take issue with his admonishment to American companies to emulate Europe's "practical approach" to innovation and manufacturing. There was absolutely no reason to dissuade and throttle activity here ...

Advanced MMICs Aid in Reducing Size and Power in Phased Array Radar Systems

Advanced MMICs Aid in Reducing Size and Power in Phased Array Radar Systems - RF CafeCustom MMIC, a leading designer and manufacturer of high performance monolithic microwave integrated circuits (MMICs), has posted a new blog entry entitled, "Advanced MMICs Aid in Reducing Size and Power in Phased Array Radar Systems." Phased-array radar systems are important instruments in national electronic defense strategies. From the large, ship-based systems that scan for distantly launched missiles to the more compact arrays installed on fighter aircraft and unmanned aerial vehicles (UAVs), electronic phased-array radars come in many sizes and forms, providing reliable signal detection and identification. These modern systems offer many advantages over earlier radar ...

Units Converter

Units Converter - RF CafeThere is a plethora of special purpose calculators and units conversion resources available online. As with most things on the Internet, you need to verify the accuracy of results when using any of them for the first time. One units conversion website I have used many times for swapping between SAE and metric units, and when needing to find alternate forms of electrical units like volts/meter to Newtons/coulomb, is UnitConverter.net. A nice feature is that the equivalent numerical values are instantly displayed for all alternate units as well as for the new units you are seeking. I did not find a furlong per fortnight unit for speed, though ;-)  The site also provides an assortment of calculators.

The Smith Chart

The Smith Chart (Ward Silver, Nuts & Volts) - RF CafeWard Silver (N0AX) wrote a monthly column for the ARRL's QST magazine for nearly decades before shifting over to Nuts & Volts a couple years ago. Mr. Silver nowadays writes "The Ham's Wireless Workbench," which as the title implies addresses the RF and microwave aspect of electronics to complement the analog and digital aspects of the magazine. In the March/April 2019 issue is an article entitled, "The Smith Chart," a subject that can make a grown man cry upon initial introduction. Ward, in his inimitable style, helps make the subject approachable. Only the first two pages (of six) are available online, so you will need to either pay for full access or do as I do and get a copy from the public library.

SpaceX Satellites Pose New Headache for Astronomers

SpaceX Satellites Pose New Headache for Astronomers - RF CafeThis was predicted, but it doesn't matter. "It looked like a scene from a sci-fi blockbuster: an astronomer in the Netherlands captured footage of a train of brightly-lit SpaceX satellites ascending through the night sky this weekend, stunning space enthusiasts across the globe. But the sight has also provoked an outcry among astronomers who say the constellation, which so far consists of 60 broadband-beaming satellites but could one day grow to as many as 12,000, may threaten our view of the cosmos and deal a blow to scientific discovery. The launch was tracked around the world and it soon became clear that the satellites were visible to the naked eye: a new headache for researchers who already have to find workarounds to deal with objects cluttering ..."

Anatech Electronics: Off-the-Shelf and Custom RF & Microwave Filters

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

Monday 10

Commercial Aspects of Single-Sideband

Commercial Aspects of Single-Sideband, June 1956 Radio & Television News - RF CafePrior to phasing-based single sideband generation circuits, a brute force filtering of the unwanted sideband and carrier signals was required. Depending on how well the carrier was suppressed, more than half the total signal power could be lost. According to author Jack Brown in this "Commercial Aspects of Single-Sideband" article from a 1956 issue of Radio & Television News magazine, it had only been since the mid 1940s that wide-band audio-frequency phase-shift networks were even feasible. An ideal implementation of a single-sideband suppressed-carrier modulator (SSB-SC) would result in 100% efficiency, but typical results are in the 80% range ...

The Engineer's 2019 Salary Survey

The Engineer's 2019 Salary Survey - RF CafeThe Engineer website just posted the results of its "The Engineer's 2019 Salary Survey." As you can see, this is primarily an UK survey (understandable since The Engineer is a UK entity), and the result shows, "a significant increase in engineering pay." It reports by industry, not specific types of engineer; e.g, electrical, mechanical, etc. Energy / renewables / nuclear is the top paying field at £58,695 ($74,377), Telecoms & utilities / electronics fell in the middle at £51,825 ($65,711), and academia came in last at £43,830 ($55,574). Those numbers do not incorporate benefits and, in the case of academia, the value of job security in the form of tenure.

Many Thanks to MECA Electronics for Their Long-Time Support!

MECA ElectronicsSince 1961, MECA Electronics has designed and manufactured an extensive line of RF & microwave components for in-building, satellite, radar, radio, telemetry, mobile radio, aviation & ATC. Attenuators, directional & hybrid couplers, isolators & circulators, power dividers & combiners, loads, DC blocks, bias-Ts and adapters & cables. MECA has long been the 'backbone' of high performance wired and air-interfaced networks such as in-building applications, satellite communications, radar, radio communications, telemetry applications, mobile radio, aviation & air traffic communications. 

USAF Recruitment Advertisement - Precision Approach Radar

USAF Recruitment Advertisement - Precision Approach Radar, April 1960 Popular Electronics - RF CafeThis is cool. I saw a U.S. Air Force recruitment advertisement in a 1960 edition of Popular Electronics pitching careers as radar operators (air traffic control) and technicians (maintenance). The picture has the dual-display glide path and elevation sweeps from the MPN/13/14 radar system that I worked on in the late 1970s - early 1980s. A photo I took circa 1980 of our unit based at Robins AFB, Georgia, is shown below. The precision approach radar (PAR) operated at x-band (10 GHz) with an operational range of 10 nautical miles. The azimuth and elevation antennas were mechanically swept with motors that changed the geometry of a waveguide having dipole stubs along its length. The entire PAR system ...

Clear Microwave Listing Added to Vendor Pages

Clear Microwave logo - RF CafeClear Microwave, of Malvern, PA, manufactures an extensive line of N-way dividers / combiners (reactive & resistive), high power combiners, directional couplers, 90° & 180° 3 dB hybrids couplers, RF switches, phase shifters, limiters, detectors, bias Tees, and DC blocks. Frequency ranges for products range from DC to 40 GHz, with CW power handling to 500 W, depending on device.

DARPA to Have AI Rule Wireless Spectrum

DARPA AI Rule Wireless Spectrum - RF Cafe"DARPA's Spectrum Collaboration Challenge demonstrates that autonomous radios can manage spectrum better than humans can. In the early 2000s, Bluetooth almost met an untimely end. The first Bluetooth devices struggled to avoid interfering with Wi-Fi routers, a higher-powered, more-established cohort on the radio spectrum, with which Bluetooth devices shared frequencies. Bluetooth engineers eventually modified their standard - and saved their wireless tech from early extinction - by developing frequency-hopping techniques for Bluetooth devices, which shifted operation to unoccupied bands upon detecting Wi-Fi signals. Frequency hopping is just one way to avoid interference, a problem ..."

Axiom Test Equipment: Rent, Buy, Trade & Repair

Axiom Test Equipment - RF CafeAxiom Test Equipment allows you to rent or buy test equipment, repair test equipment, or sell or trade test equipment. They are committed to providing superior customer service and high quality electronic test equipment. Axiom offers customers several practical, efficient, and cost effective solutions for their projects' TE needs and is committed to providing superior customer service and high quality electronic test equipment. Please check out Axiom Test Equipment today!

Sunday 9

Engineering & Science Crossword for June 9

Engineering & Science Crossword Puzzle June 9, 2019 - RF CafeSince 2000, I have been creating custom engineering- and science-themed crossword puzzles for the brain-exercising benefit and pleasure of RF Cafe visitors who are fellow cruciverbalists. The jury is out on whether or not this type of mental challenge helps keep your gray matter from atrophying in old age, but it certainly helps maintain your vocabulary and cognitive skills at all ages. A database of thousands of words has been built up over the years and contains only clues and terms associated with engineering, science, physical, astronomy, mathematics, chemistry, etc. You will never find a word taxing your knowledge of a numbnut soap opera star or the name of some obscure village ...