Homepage Archive - November 2020 (page 2)

Friday 13

Mac's Service Shop: Servicing "Too-New" Sets

Listen to the RF Cafe Podcast. At the time this Mac's Service Shop episode appeared in a 1957 issue of Radio & TV News magazine, electronics technicians were beginning to see a lot of transistorized radios, televisions, record players, and tape recorders showing up in place of the very familiar vacuum tube models. It was a whole new ballgame. To complicate matters, biasing, interstage coupling, and tuning circuits were in many ways different requiring re-learning what a "typical" circuit looked like, and the introduction of printed circuit boards in place of point-to-point wiring made changing components more difficult. Delaminating metal traces was easy to do on early PCBs when using the big, high thermal inertia soldering irons required for larger and more heat-tolerant components. Author John T. Frye used these Mac's Service Shop stories...

Withwave Intros 2.4 mm to 3.5 mm Adapter Series

"withwave-precision-2d4-3d5-mm-adapters-11-11-2020.htm" target="_top"> Withwave's Precision "withwave-precision-2d4-3d5-mm-adapters-11-11-2020.htm" target="_top"> 2.4 mm to 3.5 mm Adapter Series are designed based on precision microwave interconnection technologies. These adapters are manufactured to precise microwave specifications and constructed with either male or female gender sides. The precision microwave connector interfaces ensure an excellent microwave performance up to 34 GHz. Impedance: 50 Ω, VSWR: 1.25:1 (max) to 34 GHz, Body: Stainless steel (passivated), Center Contact: Gold-plated brass...

Flexible and Transparent Electronics Fabricated Using 2-D Semiconductor

"In recent years, engineers worldwide have been trying to create electronic components that are increasingly flexible and versatile, as this could enable the fabrication of more sophisticated devices and robotic systems, such as electronic skins (e-skins) or wearable sensors. The overall objective of this particular area of research is to develop flexible electronics that can be manufactured and implemented on a large scale, but that also exhibit a high device density and excellent performance. A class of materials with particular promise for developing flexible electronic parts are two-dimensional (2-D) semiconductors, such as molybdenum disulfide (MoS2). While this material has many advantageous mechanical, optical and electronic properties, it has so far proved challenging to build large-scale, flexible integrated circuits with a high device..."

Radar Scores SAC Bombing Test

Most people have heard of the incredibly accurate Norden bombsight (see video of the Norden bombsight) that was credited for revolutionizing accuracy of heavy bombers like B-17s, B-24s, and B-29s. It was an electromechanical device that took bombardier inputs of altitude, airspeed, heading, and wind speed and direction, then calculated the impact point of the bomb. An accuracy of 75 feet was claimed under ideal conditions - provided by a mechanical computing device. By 1956 when this article was published (eleven years after WWII and three years after Korea), the Norden had been replaced by radar-integrated bombing systems. Additionally, ground-based radar measurement systems were in use to train aircrews without the need to drop physical bombs. Instead, virtual bombs were launched and computers in a Radar Bomb Scoring (RBS) unit...

Many Thanks for KR Electronics' Long-Time Support!

KR Electronics designs and manufactures high quality filters for both the commercial and military markets. KR Electronics' line of filters includes lowpass, highpass, bandpass, bandstop and individually synthesized filters for special applications - both commercial and military. State of the art computer synthesis, analysis and test methods are used to meet the most challenging specifications. All common connector types and package form factors are available. Please visit their website today to see how they might be of assistance. Products are designed and manufactured in the USA.

EMA Structural Forensic Engineers

EMA Structural Forensic Engineers wrote requesting addition to the Expert Witness, Tech Services, and Forensic Engineering pages on RF Cafe, which I was glad to do*. EMA assists architects, the legal profession, and the insurance community in the investigation and redesign of structures. We solve design issues of already designed buildings and performing damage assessment. Damage assessment of roofs, hail damage inspections, forensic building damage inspections, forensic engineering, flood damage assessments, and hurricane damage assessment. *I also cleaned up a lot of expired company links - they need some forensic services now.

Many Thanks to San Francisco Circuits for Continued Support!

SF 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."

Thursday 12

New Radio-Electronic Patents

It has been three or four decades since I have seen anything about a Lecher Line, the last time in memory being in a college lab. It might have been a physics lab, but most probably an EE lab. We used one to measure wavelengths of signals from an RF generator. The apparatus looked sort of like the one in the Wikipedia link, only just a little more modern (but not much more, being typical school equipment). This new patents report from a 1947 issue of Radio-Craft magazine has a waveguide version of a Lecher Line that supposedly was able to do more precise measurements of very short wavelengths by providing for detecting the internal wave over multiple wavelengths instead of just a single half wavelength. It was developed at Bell Telephone Laboratories...

Linx Launches Flexible Embedded FPC Series Antennas

"Linx-Technologies-Flexible-Embedded-FPC-Series-Antennas-11-11-2020.htm" target="_top"> Linx Technologies, a Merlin, OR, based developer and manufacturer of antennas, is pleased to introduce the latest additions to the "Linx-Technologies-Flexible-Embedded-FPC-Series-Antennas-11-11-2020.htm" target="_top"> FPC Series of flexible embedded antennas. The FPC Series antennas excel in a wide range of applications, including 5G cellular, WiFi 6/6E, low-power wide-area networking (LPWA), and ISM. In this latest release, Linx is adding two 5G antennas, a WiFi antenna supporting the new 6 GHz band, a 433 MHz LPWA offering, and an ISM antenna supporting both 868 MHz and 915 MHz. The FPC Series provides ground plane independent dipole embedded antenna solutions comparable in performance to external antennas. The flexibility and adhesive backing make the FPC Series easy to mount in unique and custom enclosures...

Schematic Symbol Stamps

Even in this time of readily available computers (including your smartphone) and printers, having a set of rubber stamps for common electronics symbols would be pretty handy; there are some Neanderthals among us who still use pencil and paper on occasion. Simpler symbols like resistors and capacitors are easy enough to sketch by hand, but something like a dual gate MOSFET with diode protection can take some time to produce legibly. Common connector types like the DB signal/power series and some RF kinds (BNC, SMA, etc.) would be useful, as would a set of oft-used logic gates for the digital designers. The set shown here in a 1953 edition of Radio-Electronics magazine includes a handful of vacuum tube types which would have taken some time to draw by hand, and a few other symbols...

Lens Antennas Aim to Provide Better Connectivity at Public Venues

"The demand for bandwidth has been increasing continuously in the cellular world and there are no indications of it slowing down. This is true in large public venues as well, such as arenas and stadiums, where the fans require large bandwidths to communicate and send pictures / videos. Using Lens Antennas in these scenarios not only increases cellular coverage and capacity in venues, but it can do that at a lower cost than traditional methods with the added advantage of improved aesthetics. The problem for venue owners and operators is to satisfy the ever-increasing requirement for connectivity. There is an increased need for lower latency as well with the introduction of live mobile gaming inside venues. Lens Antennas can be deployed in such venues which have multi-radio..."

Atomic Clock to Check Einstein

Albert Einstein published his paper on Special Relativity in 1905 and on General Relativity in 1916. Since that time, many experiments have been performed worldwide by scientists intent on both proving and disproving Mr. Einstein. Laser and nuclear based timepieces have been improved for precision and calculations refined to aid in the task. This 1959 Popular Electronics magazine article reports on one of the first atomic clock experiments used to test General Relativity. After more than 100 years, General Relativity stands as originally presented. Even the rigors of quantum mechanics, which Einstein did not embrace until much later in life, has not toppled its precepts...

Empower RF Systems Intros S-Band Magnetron Driver

"Empower-RF-Systems-S-Band-Magnetron-Driver-2d9-3d5-GHz-11-9-2020.htm" target="_top"> Empower RF announces the production release of our "Empower-RF-Systems-S-Band-Magnetron-Driver-2d9-3d5-GHz-11-9-2020.htm" target="_top"> Model 2239 pulsed driver amplifier producing a minimum of 1 kW peak power. The 2239 is an intelligent amplifier in a compact 3U rack compatible footprint with features ideal for integrating into Magnetron, IOT, Klystron and TWT systems. The amplifier is designed for 0 dBm input that is pulse modulated. A fast TTL gate input is standard, and its use optional when complete shutoff of the output stage is desired between pulses. Pulse capabilities include up to 20% duty cycles and pulse widths as long as 500 μsec with up to 25 kHz PRF's. GaN on SiC devices are used in a multistage class AB configuration. Full self-monitoring protection is included and will self-protect with sudden open/short conditions and is tolerant to VSWR up to 3:1...

Many Thanks for Alliance Test Equipment's Support!

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

Wednesday 11

A Modern View of Permanent Magnet Theory

This first installment in a multi-part series on magnetism appeared in the October 1947 issue of Radio-Craft magazine. At the time, there was great interest in magnetic tape and even magnetic wire recorders. Lots of articles were published on the electronics and mechanics of recorders, but relatively few discussed the physics of magnetics. Although the title says it is about permanent magnetic theory, there is also a lot of information on electromagnets. Terms such as reluctivity, magnetomotive force, magnetic flux, conductivity of electrical and magnetic circuits, conductance, B-H curves, maxwells, oersteds, and gilberts are introduced, along with some simple equations relating everything...

Students Design Custom Satellites

"Engineering students at the University of Cincinnati are building tiny custom CubeSat satellites to test the radiation shielding properties of carbon fiber material and take high-resolution photos of the Great Lakes from space. LEOPARDsat-1 will record how much radiation from space seeps through different thicknesses of carbon-polyethylene samples. HABsat1 relies on an internal flywheel system in which motor-driven spinning flywheels can orient a satellite on three axes..."

Many Thanks to Empower for Long-Time Support

Empower 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.

This Business of Code

Proficiency in Morse code is no longer required as part of obtaining an Amateur Radio license. A proposal to drop the 5 wpm requirement was first floated by the FCC in 2005. It was actually at the request of the ARRL; to wit, "In 2004, the League called on the FCC to create a new entry-level license, reduce the number of actual license classes to three and drop the Morse code testing requirement for all classes except for Amateur Extra." ARLB018 FCC Proposes Dropping Morse Code Requirement Entirely Now, there is no code requirement for any license class, not even the Amateur Extra. A lot of Hams are not happy about it, but times have changed and the need for code proficiency just is not needed anymore because of the plethora of communications formats available. No small part of the ARRL's motivation for requesting that code proficiency be dropped...

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

RF 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 job openings. HR department employees and/or managers of hiring companies are welcome to submit opportunities for posting at no charge (of course a gratuity will be graciously accepted). 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...

Veterans Day Tribute 2020

The eleventh hour of the eleventh day of the eleventh month - November 11th, at 11:00 am - that is when the armistice (cease fire) began in 1918, unofficially ending World War I. This music video Veteran's Day tribute is by Canadian citizen Terry Kelly. It was written after an experience he had on Veterans Day in 1999. Terry went blind at an early age, but has excelled as an athlete and a musician. "A Pittance of Time" is done in the finest Celtic tradition. Per the U.S. Department of Veteran Affairs website: "World War I – known at the time as 'The Great War' - officially ended when the Treaty of Versailles was signed on June 28, 1919, in the Palace of Versailles outside the town of Versailles, France. However, fighting ceased seven months earlier when an armistice, or temporary cessation of hostilities, between the Allied nations and Germany went into effect on the eleventh hour of the eleventh day of the eleventh month. For that reason, November 11, 1918, is generally regarded as the end of 'the war to end all wars...'"

Please Thank RF Superstore for Their Continued Support

RF Superstorelaunched in 2017, marking the return of Murray Pasternack, founder of Pasternack Enterprises, to the RF and microwave Industry. Pasternack fundamentally changed the way RF components were sold. Partner Jason Wright manages day-to-day operations, while working closely with Mr. Pasternack to develop RF Superstore into a world class RF and microwave component supplier. RF coaxial connectors & adapters, coaxial cable & cable assemblies, surge protectors, attenuators. Items added daily. Free shipping on orders over $25. We're leading the way again!

Tuesday 10

Wire Wrap: Bell Telephone Laboratories

After getting out of the U.S. Air Force in 1982, I was fortunate to get a job at the Oceanic Division of Westinghouse Electric Corporation in Annapolis, Maryland. Most of the guys who worked in the area with me were former electronics technicians from the armed forces. We spent most of our days (and often evenings) building small quantity specialty systems for the U.S. Navy. The facility was fairly small and was not set up for high volume production; that was the purview of the much larger operation based adjacent to the Baltimore / Washington International Airport (BWI), which built ground-based and airborne radar systems. Whilst there, I did a lot of wire-wrap assemblies that went into MIL-SPEC systems, primarily rack-mounted equipment in helicopters and aboard ships deploying towed sonar systems. As such, I received extensive training for performing soldering, wire-wrapping...

Gowanda Announces Expansion of Its DYCO Electronics Facility

"Gowanda-Expansion-DYCO-Electronics-Facility-11-10-2020.htm" target="_top"> Gowanda Components Group is pleased to announce the completion of a nearly 50% expansion at its DYCO Electronics facility in Hornell, New York. The 12,000 sq. ft. expansion will help the company address market demand for its products, enhance work flow and improve operational efficiency. "We manufacture custom components and assemblies for the rail industry, so size and scale were important drivers for this expansion," said Greg Georgek, President of DYCO Electronics. "In addition, we've seen growth in our overall custom manufacturing business in recent years – with projections for that to continue – as our customers have increased their outsourcing of more assemblies to DYCO," Georgek added. DYCO engineers custom solutions for aerospace, military, space, medical...

Please Thank MECA Electronics for Their continued Support!

Since 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. 

Axiom Blog: Keep the Light Shining on Solar Power Systems

"Axiom-Test-Equipment-Keep-Light-Shining-Solar-Power-Systems-11-5-2020.htm" target="_top"> Axiom Test Equipment, an electronic test equipment rental and sales company has published a new blog post titled "Keep the Light Shining on Solar Power Systems" that covers maintenance programs on solar power systems in order to achieve optimum results. This maintenance can be greatly simplified with the right test tools. Learn which components in any solar power system that should be regularly tested as part of a maintenance program. In general, maintenance should involve the main system parts like solar panels, energy storage units, inverts, and their interconnections, and their price performance parameters. Main test tools for checking solar power systems should provide measurements of power, voltage, and current at maximum levels that exceed the performance limits of the solar power system's components...

Getting to Know the UJT

The unijunction transistor (UJT), invented in 1953, was originally known as a "double-base diode" and explains why to this day the terminals are labeled "E," "B1,' and B2." It is commonly modeled as a diode connected between two resistors, with one resistor being variable. As the name implies, unlike a bipolar junction transistor (BJT) that is more familiar to most people and has two semiconductor junctions connected to the base, a UJT has just one junction. As is explained in detail in this 1970 Popular Electronics article, the net effect of the UJT's arrangement is a region of negative resistance which makes it good for use as an oscillator. In fact, the relaxation oscillator...

Many Thanks to Reactel for Their Long-Time Support!

Reactel has become one of the industry leaders in the design and manufacture of RF and microwave filters, diplexers, and sub-assemblies. They offer the generally known tubular, LC, cavity, and waveguide designs, as well as state of the art high performance suspended substrate models. Through a continuous process of research and development, they have established a full line of filters of filters of all types - lowpass, highpass, bandpass, bandstop, diplexer, and more. Established in 1979. Please contact Reactel today to see how they might help your project.

Monday 9

Microtubes - A New Milestone in Electronic Developments

A month before Bell Laboratories' announcement of the transistor invention by Mssrs. Bardeen, Shockley and Brattain, Radio-Craft magazine editor Hugo Gernsback published a piece extolling the virtues of a newly developed microtube, aka a "rice-grain" tube. As connected as Gernsback was in the electronics industry, it is doubtful he knew of the impending game-changing invention. Commercialization of the transistor took a few years to get to the point where the devices could be manufactured cheaply and reliably enough to begin being integrated (pun intended) into products, so vacuum tubes still reigned for another decade or more. While the microtubes were designed into such products as portable radios, hearing aids, and other things in desperate need of size reduction, standard tubes continued to be used in the majority of things...

NEW! Windfreak "SynthUSB3" 12.5 MHz to 6.4 GHz RF Signal Generator

"Windfreak-Technologies-SynthUSB3-11-5-2020.htm" target="_top"> Windfreak Technologies announces the availability of the new "Windfreak-Technologies-SynthUSB3-11-5-2020.htm" target="_top"> SynthUSB3 RF Signal Generator. The SynthUSB3 thumb drive sized RF Signal Generator is designed for extremely high quality to cost ratio. These devices have set the bar on microwave radio frequency generators for quality, size and price. As always, our products are designed, manufactured and supported in the USA - and it arrives already calibrated! Tune any frequency between 12.5 MHz and 6.4 GHz in 0.01 Hz resolution. Adjust calibrated amplitude in 0.2 dB resolution up to +8 dBm and across more than 50 dB of range. 500 point frequency and amplitude hop table. Expect excellent performance and high reliability despite the SynthUSB3's low cost...

Blowtorching Tubes to Life

If this article had appeared in the New York Times in the year 2020, its author, Glenn Ellsworth, would have been labeled a 'Depression Denier!' Don't be confused by the word 'denier,' which most often prior to about 1999 was used to refer to a type of silver coin or a measure of fineness of silk cloth. Today, it is seen most often as describing one who would deny something. 'Denyer' is the alternate spelling used by some authors to avoid confusion, and since the level of spelling knowledge is so low, most people never notice. But, I digress. The reason I bring up the point is because this article was published in 1933, little more than three years after the Stock Market Crash of October 29, 1929 (aka 'Black Tuesday')...

Many Thanks to Exodus Advanced Communications for Their Support

Exodus 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.

3D EM Field Solver Focuses on Antenna Design and Optimize Planar Filter

Jeffrey Kahler and Andreas Wien have an article in Microwaves & RF magazine that shows how two disparate software programs can be used together to design and optimize a system segment consisting of the antenna and an associated planar filter. "For many years, IMST has been in the business of producing expert 3D electromagnetic (EM) simulation software. With its Empire XPU product, IMST emphasizes and focuses on antenna design and optimization. Nuhertz Technologies has also been around for many years, producing expert filter design software. And with its FilterSolutions tool, the company focuses on accurate 3D planar design and optimization. Therefore, it seems a natural fit for these two products to work together so that users can take advantage of the best features of both. Specifically, IMST's Empire XPU EM optimization process can be used on planar designs created with Nuhertz's FilterSolutions..."

Many Thanks to Electro-Photonics for Their Continued Support

Electro-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. 

Sunday 8

Famous Engineers & Scientists Crossword Puzzle for November 8th

This Famous Engineers & Scientists crossword puzzle took a long time to make because of all the names that I managed to squeeze into the matrix. The way this one works is the person's first initial and completely spelled-out last name, indicated by (FI+LN) in the clue, is used as the answer. For instance, filter transfer function developer Stephen Butterworth would be written as SBUTTERWORTH. There are at least sixteen names here There are at least sixteen names here with which you should be familiar. Good luck!

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. Some quoted items have been shortened to save space. About RF Cafe.

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