Left Border Content - RF Cafe
Windfreak Technologies
Res-Net Microwave - RF Cafe
 

About RF Cafe

Kirt Blattenberger - RF Cafe Webmaster

Copyright: 1996 - 2024
Webmaster:
    Kirt Blattenberger,

    BSEE - KB3UON

RF Cafe began life in 1996 as "RF Tools" in an AOL screen name web space totaling 2 MB. Its primary purpose was to provide me with ready access to commonly needed formulas and reference material while performing my work as an RF system and circuit design engineer. The World Wide Web (Internet) was largely an unknown entity at the time and bandwidth was a scarce commodity. Dial-up modems blazed along at 14.4 kbps while typing up your telephone line, and a nice lady's voice announced "You've Got Mail" when a new message arrived...

All trademarks, copyrights, patents, and other rights of ownership to images and text used on the RF Cafe website are hereby acknowledged.

My Hobby Website:

AirplanesAndRockets.com

Header Region - RF Cafe
Electronics World articles Popular Electronics articles QST articles Radio & TV News articles Radio-Craft articles Radio-Electronics articles Short Wave Craft articles Wireless World articles Google Search of RF Cafe website Sitemap Electronics Equations Mathematics Equations Equations physics Manufacturers & distributors Engineer Jobs LinkedIn Crosswords Engineering Humor Kirt's Cogitations RF Engineering Quizzes Notable Quotes App Notes Calculators Education Engineering magazine articles Engineering software Engineering smorgasbord RF Cafe Archives RF Cascade Workbook 2018 RF Symbols for Visio - Word Advertising RF Cafe Homepage Thank you for visiting RF Cafe!
Sub-Header - RF Cafe Exodus Advanced Communications Best in Class RF Amplifier SSPAs
Homepage Archive - June 2019 (page 3)

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

Homepage Archive Pages

2021:  Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec
2020:
  Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec
2019:
  Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec
2018:  Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec
2017:  Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec
2016:  Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec
2015:  Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec
2014:  Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec
2013:  Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec
2012:  1 | 2 | 3 | 4 | 5 | 6 | 7 | 8 | 9 | 10 | 11 | 12 | 13


See Page 1 | 2 | 3 | 4 | 5 of the June 2019 homepage archives.
col-width

Friday 21

Editorial - High Life: The Bill Comes Due

Editorial - High Life: The Bill Comes DueAccording to Electronics magazine editor Lewis Young in mid-1964, the industry was entering into a slump in business opportunities. The boom times provided during the war years of WWII and Korea had resulted in, according to Mr. Young, a lax attitude toward operational strategy that led to wasteful spending and poor accountability for project results. It wasn't just the defense contractors' fault because government bureaucrats - from relatively low ranking military personnel to elected lawmakers - had (have) a habit of making sudden changes to contract requirements. Maintaining the resources needed to keep up with ever-evolving demands necessitated a lot of the excess. Fortunately, the military-industrial complex, as President Dwight D. Eisenhower dubbed it, was on the verge of being thrown another huge monetary bone - the Vietnam War. President Kennedy was already pumping lots of equipment and manpower into it, and LBJ would follow suit with vigor ...

R&S June Newsletter

Rohde & Schwarz June Newsletter - RF CafeRohde & Schwarz just posted their latest monthly newsletter reporting on topics including "Measurement of Phase Noise of Local Oscillators" that has a video along with it, a "Battery Life Optimization in IoT Devices" app note, "Automotive Radar Test Solutions Using Oscilloscopes" which covers the 77 GHz band, "Optimize Beamforming: From Bits to RF Beams "using phased arrays. As always, everything is good.

Electrical Power / Force, NAVPERS 10622

Chapter 7: Electrical Power / Force, NAVPERS 10622 - RF CafePower, energy, force, and work are all physical entities whose definitions are often incorrectly interchanged. As with most cases in physics, knowing the unit associated with each entity is a way to remember what it represents. For instance, force is fundamentally understood as a mass being acted upon by an acceleration - whether it be gravity or motion. Its SI units are kg·m/s2 (newton, with dimensions of mass x length / time2). Energy is a force in motion (or its potential by virtue of relative position) with units of force x mass (joule, with dimensions of mass x length2 / time2), and an electrical unit of watt·seconds (power x time). Work is force through a distance, with dimensions of mass x length2 / time2, which is the same ...

Seeing Around Corners to Detect Object Shapes

Seeing Around Corners to Detect Object Shapes - RF Cafe"Computer vision researchers have demonstrated they can use special light sources and sensors to see around corners or through gauzy filters, enabling them to reconstruct the shapes of unseen objects. The researchers from Carnegie Mellon University, the University of Toronto and University College London said this technique enables them to reconstruct images in great detail, including the relief of George Washington's profile on a U.S. quarter. Ioannis Gkioulekas, an assistant professor in Carnegie Mellon's Robotics Institute ..."

Thanks to Transient Specialists for Continued Support!

Transient Specialists - RF CafeTransient Specialists specializes in EMC test equipment rentals and carries a complete line of ESD guns, surge immunity test equipment, and EFT generators. Rentals available for military (Mil-Std 461), automotive (ISO 7637), and commercial (IEC 61000-4) EMC testing. Flexible terms, accredited calibrations and technical support on EMC testing equipment offered. Equipment consists of top EMC Test System manufacturers, including Teseq, Thermo Keytek, EM Test and EMC Partner.

Electro-Photonics Offering RF & Microwave Products

Electro-PhotonicsElectro-Photonics is a global supplier of RF & Microwave components. Their products include SMT hybrid and directional couplers, wire bondable passive components, mounting tabs, filters, transmission lines, and very useful test boards for evaluating components (spiral inductors, single-layer capacitors). The Electro-Photonics team can support your small R&D design requirements with RF & Microwave test fixtures and save you valuable design and characterization time. Please take a moment to visit Electro-Photonics' website and see how your project might benefit.

Thursday 20

Antenna Performance Key to Good Color Reception

Antenna Performance Key to Good Color Reception, May 1969 Sylvania News - RF CafeThere was a time that selecting a television antenna was as important to the quality of life as buying the right smartphone is today. There were probably as many choices in antennas then as there are phones now. You might think, especially if you are not an amateur or military radio operator, that nobody worries about antennas anymore, but as I've written before there is a slight resurgence in people installing the old fashioned multi-element antennas for receiving local television and radio stations. The market's not huge, but seems to be keeping companies like Channel Master in business. Incidentally, in contrast to my aforementioned comment, dig the opening sentence of the article: "Virtually no one in this day and age goes about discussing the reception quality of his telephone."

More on Desktop Printed Circuit Boards

JTK Communications Desktop Printed Circuit Boards - RF CafeLong-time RF Cafe visitor Alan Dewey, of JTK Communications, wrote to tell me about the good results he has had with a recently acquired desktop printed circuit board (DPCB) setup. Alan has been documenting his experience in a blog on the TwoHourPCBs.com website, and plans to continue as the project progresses. The particular system he is using can handle 2-layer boards, drill holes, and perform through-hole plating. Line widths down to 0.20 mm and spacings to 0.65 mm on FR4 substrate (up to 128 x 105 mm) with pre-applied solder mask. If you have never tried the DPCB method or were not happy with the way previous attempts turned out, this might encourage a new trial.

After Class: Crystals

After Class: Crystals, April 1960 Popular Electronics - RF CafePopular Electronics magazine used to run a monthly electronics tutorial column entitled, "After Class." Various guest authors wrote the articles. All you need to do is substitute transistors for the tubes used in these fundamental oscillator circuits to bring this article's content up to date. Or, maybe you are the owner of a vintage vacuum tube radio and would like to learn a little about how things were done in the olden days. Either way, as with so many aspects of electronic circuits, the basics haven't changed much in the last 100 years. It's all still good. A list of all "After Class" articles is at the bottom of the page.

Eye Diagrams: Tool for Serial Data Analysis

Eye Diagrams: Tool for Serial Data Analysis - RF CafeWhile not necessarily directly applicable to RF communications, Mr. Arthur Pini's article entitled "Eye Diagrams: The Tool for Serial Data Analysis" on the EDN website does provide some insight into how eye diagrams reveal m-ary data streams. "The eye diagram is a general-purpose tool for analyzing serial digital signals. It shows the effects of vertical noise, horizontal jitter, duty cycle distortion, inter-symbol interference, and crosstalk, all of which can close the 'eye.' While engineers have used eye diagrams for decades, oscilloscopes continually get new features that increase its value. Oscilloscopes form eye diagrams - the separation between the two binary data states '1' and '0' - by overlaying multiple single clock periods on a persistence display ..."

Carbon Atom Transforms 2D Semiconductors

Carbon Atom Transforms 2D Semiconductors - RF Cafe"A technique that introduces carbon-hydrogen molecules into a single atomic layer of the semiconducting material tungsten disulfide dramatically changes the electronic properties of the material, according to Penn State researchers at Penn State who say they can create new types of components for energy-efficient photoelectric devices and electronic circuits with this material. "We have successfully introduced the carbon species into the monolayer of the semiconducting material," said Fu Zhang, doctoral student in materials science ..."

Withwave: RF & Microwave Components

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 vector network analyzer (VNA) calibrator, between- and in-series connector adaptors, attenuators, terminations, torque wrenches, test probes & probe positioner. Frequency ranges from DC through 20 GHz. Please contact Withwave today to see how they can help your project succeed.

Wednesday 19

Radio Trade Digest

Radio Trade Digest, August 1940 Radio-Craft - RF CafeIn August of 1940, issue No. 24 of the Radio Trade Digest had a couple major historical announcements. The first is "F.C.C. Authorizes Commercial F.M.," which assigned 40 UHF (42 - 50 MHz band) commercial broadcast channels 5 non-commercial channels. Frequencies were changed to 88 - 108 MHz in 1946. The second major announcement was that Philco (founded in 1892 as Helios Electric Company, then changed to the Philadelphia Storage Battery Company in 1906) had become a publically traded company. It required private stock holders to convert and re-value their holdings to make some of them available for public sale, which or course they voted for. I don't know how IPOs worked back then, but my guess is they were not as dynamic ...

See What Your Office and Lab Walls Are Missing

See What Your Office and Lab Walls Are Missing - RF CafeHewlett Packard (HP), Agilent Technologies, and Keysight Electronics (all versions of the same company, BTW) have for decades been offering very cool, colorful, and highly informational (and free) wall posters that are great for your cubicle and/or lab walls. Before the ready availability of practically all available technical resources on the Internet via your smartphone, those posters were an invaluable source of relevant system specifications, definitions, operations, and formulas. Keysight has just announced 5 new technical posters and 8 new Keysight Education Forum (KEF) technical papers and videos.

Fabricate PCBs at Your Desk

Fabricate PCBs at Your Desk - RF CafeMicrowave Journal has an article (in infomercial, actually) entitled "Fabricate PCBs at Your Desk" that describes the first tabletop LPKF laser etching system, named ProtoLaser ST. As an example of its capabilities, a planar logarithmic periodic wideband antenna was fabricated measuring 60 mm x 60 mm. Features as small as 217 um has finished accuracy errors of around 3%, while those at 1853 um exhibited errors of around 0.1%, depending on the substrate used. ProtoLaser ST is capable of making multilayer boards and can drill and electroplate through-holes.

How Does Match Affect My Power Measurement?

How Does Match Affect My Power Measurement? - RF CafeMr. Orwill Hawkins has a great article posted on the High Frequency Electronics website entitled, "How Does Match Affect My Power Measurement?" Some people, particularly - but not limited to - beginners in the RF field, are not familiar with how VSWR mismatch can affect not just power levels within a systems, but also frequency response and phase. For instance, when you buy a filter with a specific frequency response when designed for a 50+j0 Ω impedance and connect it to another component with a different complex impedance, the measured response will not match the spec. It might perform well enough, but it won't be exactly like your predicted response. This article provides a little insight into the mechanism at work.

Hidden Structure in the Periodic Table

Hidden Structure in the Periodic Table - RF Cafe"The periodic table of elements that most chemistry books depict is only one special case. This tabular overview of the chemical elements, which goes back to Dmitri Mendeleev and Lothar Meyer and the approaches of other chemists to organize the elements, involve different forms of representation of a hidden structure of the chemical elements. This is the conclusion reached by researchers at the Max Planck Institute for Mathematics in the Sciences in Leipzig and the University of Leipzig in a recent paper. The mathematical approach of the Leipzig scientists is very general and can provide many different periodic systems depending on the principle of order and classification - not only for chemistry, but also for many other fields of knowledge ..."

TotalTemp Technologies: Thermal Platforms for −100°C to +200°C

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.

Tuesday 18

Portable Radar Becomes a Reality

Portable Radar Becomes a Reality, July 1971 Popular Electronics - RF CafeYour idea of a usable portable radar probably does not include one that requires you to manually point it at your surroundings and listen through a set of earphones for a tone's volume and pitch to estimate distance to the target (or you can use the small analog meter on the case. That was considered a technological breakthrough in 1971, and Kimball Product Company's "Whistler" was the star. It only cost $595 ($3,743 in 2019 dollars) for the capability. The trade name "Whistler" is very well known today, but I could not find any information relating it to its namesake in this article. There is a Kimball Electronics, but their About Us page is down at this time. Most likely, though, it is The Whistler Group that is the progenitor of the radar unit mentioned here. Today, they have an extensive line of portable radar units for marine, automotive, aviation, and other applications ...

NanoVNA Vector Network Analyzer 50 kHz - 900 MHz

NanoVNA Vector Network Analyzer 50 kHz - 900 MHz - RF CafeAn RF Cafe visitor wrote to say he purchased one of these hand-held 50 kHz to 900 MHz vector network analyzers for under $100, and was very pleased with its performance. This is a fully self-contained VNA (S11 and S21 measurements) with all functionality built in, and even has a full color touch-screen display. Dynamic range runs from 50 to 70 dB, depending on the frequency band. It does not require an external device for use, although a USB connection is provided for data transfer (cable included). Two SMA cables and a "simple calibration kit" comes with it as well. The VNA is sold under a few different names, as are many of the incredibly inexpensive test equipment items sold online.

Printed Circuits

Printed Circuits, December 1949 Radio & Television News - RF CafeMost people today under 30 years old have probably never seen the mechanics or electronics inside their many personal devices. Everything is so miniaturized and optimized that if something does go wrong, there is little chance of the owner repairing it. Instead, the phone, television, stereo, microwave oven, whatever, gets thrown away and a relatively cheap (compared to paying for a repair) replacement is purchased (or stolen). Besides, if the item was more than two years old, it was on the verge of obsolescence anyway. Up until around the early to mid 1980s you had a fair chance of being able to repair an electronic circuit if trouble arose because at least with commercial products printed circuit boards (PCBs) were usually 1- or 2-sided and the components still had leads protruding from the sides of the packages ...

Many Thanks to Rohde & Schwarz USA for Continued Support!

Rohde & Schwarz USA Pocket Guides - RF CafeRohde & Schwarz develops, produces and markets test & measurement, information and communications technology. Focus is on test and measurement, broadcast and media, cybersecurity, secure communications, monitoring and network testing. Markets serviced are wireless, the automotive industry, aerospace and defense, industrial electronics, research and education, broadcast and media network operations, consumer electronics, cybersecurity for business and governments, communications and security solutions for critical infrastructures and the armed forces, reconnaissance equipment for homeland and external security, and much more.

VidaRF Intros Broadband Directional Couplers for 2 to 40 GHz

VidaRF Intros Broadband Directional Couplers for 2 to 40 GHz - RF CafeVidaRF, a manufacturer of high performance RF and microwave high performance circulators, isolators, couplers, power dividers, and other passive components, is proud to introduce a series of broadband directional couplers covering 2 to 40 GHz for all wireless applications from cellular through 5G mm-wave. Available 10, 16, 20, and 30 dB coupling values. All models feature low VSWR, high directivity, compact size, and finished to IP65 standards. 2.92 mm (SMA type) connector standard, with custom configurations possible. VidaRF is focused on being a solution provider by building to customer specs and offering zero days lead time for custom parts through stock ...

Laser 'Tricked' into Producing, Receiving Modulated Wi-Fi Band RF Signals

Laser 'Tricked' into Producing, Receiving Modulated Wi-Fi Band RF Signals - RF Cafe"Researchers mixed two optical outputs of a laser comb and modulated the result, then emitted this energy via an integrated dipole antenna to create an RF signal in the 5-GHz band. We think of optical lasers and microwaves as functioning in distinctly different regions and with disparate modes within the broad electromagnetic spectrum. However, it doesn't have to be that way, as proven by numerous developments in integrated electro-optics. Now, in a paper published in the Proceedings of the National Academy of Sciences with the deceptively modest title 'Radio frequency transmitter based on a laser frequency comb,' researchers from Harvard's John A. Paulson School of Engineering and Applied Sciences (SEAS) have demonstrated a laser that can emit encoded microwaves as wireless RF ..."

Transient Specialists: EMC, EMI, RFI Test Equipment Rentals

Transient Specialists - RF CafeTransient Specialists specializes in EMC test equipment rentals and carries a complete line of ESD guns, surge immunity test equipment, and EFT generators. Rentals available for military (Mil-Std 461), automotive (ISO 7637), and commercial (IEC 61000-4) EMC testing. Flexible terms, accredited calibrations and technical support on EMC testing equipment offered. Equipment consists of top EMC Test System manufacturers, including Teseq, Thermo Keytek, EM Test and EMC Partner.

Monday 17

Mac's Radio Service Shop: Summer Seminar

Mac's Radio Service Shop: Summer Seminar, June 1956 Radio & Television News - RF CafeSummer begins this week in the northern hemisphere, and winter begins south of the equator. Counterintuitive to northerners not familiar with the geometric cause of seasons (axis tilt) is that the Earth is actually closest to the sun in January than it is in July. Our orbital path is nearly circular, with an eccentricity of just 0.0167. Anyway, I thought the onset of summer would be a good time to post this installment of Mac's Radio Service Shop entitled, "Summer Seminar." Typical of author John Frye's techno-sagas, more than one theme runs through the story. It begins with shop owner Mac admonishing technician Barney for throwing away a faulty selenium rectifier when he knows there is an industry-wide shortage on supplies of the element and the bad components should be submitted for recycling. Fretting over as common an element ...

Whitepaper: High-Efficiency, Ka-Band GaN Power Amplifiers

QuinStar Whitepaper: High-Efficiency, Ka-Band GaN Power Amplifiers - RF CafeNicholas Estella, Edmar Camargo, James Schellenberg and Lani Bui, all from QuinStar Technology, Torrance, CA, wrote this whitepaper entitled "High-Efficiency, Ka-band GaN Power Amplifiers," which was presented by Mr. Estella at IMS2019 in Boston, Massachusetts. "This paper reports the design and performance of state-of-the-art GaN MMICs and a fully packaged Ka-band SSPA. Incorporating harmonic tuning, the MMICs produce power levels up to 10 W CW with efficiencies in the high thirties (42% peak) at frequencies of 30 to 34 GHz. These results represent the highest combination of CW power and efficiency at these frequencies. A 4-way combiner-SSPA, operating over 31 to 34 GHz, was assembled with these MMICs ..."

Anatech Electronics June 2019 Newsletter

Anatech Electronics June 2019 Newsletter - RF CafeAnatech Electronics, an RF and microwave filter company, has introduced a new line of suspended stripline and waveguide type RF filters. Sam Benzacar wrote as part of Anatech's June newsletter about his impressions of the IMS2019 trade show in Boston. As you might guess, the main topic is 5G and the plethora of technologies that stand to benefit from the incredible amount of bandwidth assigned to it over many heretofore largely unused frequency bands. That is part of the challenge, and the result will no doubt be the conquering of discouraging and difficult implementation issues. Also included are a few news headlines related to Anatech's core business of designing and manufacturing filters ...

Many Thanks to ConductRF for Continued Support!

ConductRF coaxial cables & connectors - RF CafeConductRF is continually innovating and developing new and improved solutions for RF Interconnect needs. See the latest TESTeCON RF Test Cables for labs. ConductRF makes production and test coax cable assemblies for amplitude and phased matched VNA applications as well as standard & precision RF connectors. Over 1,000 solutions for low PIM in-building to choose from in the iBwave component library. They also provide custom coax solutions for applications where some standard just won't do. A partnership with Newark assures fast, reliable access. Please visit ConductRF today to see how they can help your project! 

Antennas of Flexible Nanotube Films

Antennas of Flexible Nanotube Films - RF cafe"Antennas made of carbon nanotube films are just as efficient as copper for wireless applications, according to researchers at Rice University's Brown School of Engineering. They're also tougher, more flexible and can essentially be painted onto devices. The Rice lab of chemical and biomolecular engineer Matteo Pasquali tested antennas made of 'shear-aligned' nanotube films. The researchers discovered that not only were the conductive films able to match the performance of commonly used copper films, they could also be made thinner to better handle higher frequencies. At the target frequencies of 5, 10 and 14 gigahertz, the antennas easily held their own with their metal counterparts ..."

Custom MMIC: Off-the-Shelf and Custom MMICs

Custom MMIC- RF CafeCustom MMIC is a fabless RF and microwave MMIC designer entrusted by government and defense industry OEMs. Custom and off-the-shelf products include switches, phase shifters, attenuators, mixers and multipliers, and low noise, low phase noise, and distributed amplifiers. From next-generation long range military radar systems, to advanced aerospace and space-qualified satellite communications, microwave signal chains are being pushed to new limits - and no one understands this more than Custom MMIC. Please contact Custom MMIC today to see how they can help your project. 

Sunday 16

Engineering & Science Crossword Puzzle for June 16

Engineering & Science Crossword Puzzle June 16, 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 in the Andes mountains. You might, however, encounter the name of a movie star ...

   
Footer - RF Cafe Copper Mountain Technologies - RF Cafe
Right Border Content - RF Cafe
PCB Directory (Design)
Axiom Test Equipment - RF Cafe
 

Please Support RF Cafe by purchasing my  ridiculously low−priced products, all of which I created.

These Are Available for Free