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 Engineering Event Calendar RF Engineering Quizzes USAF radar shop Notable Quotes App Notes Calculators Education Engineering Magazines Engineering magazine articles Engineering software Engineering smorgasbord RF Cafe Archives RF Cascade Workbook 2018 RF Stencils for Visio RF & EE Shapes for Word Advertising RF Cafe Homepage Sudoku puzzles Thank you for visiting RF Cafe!
Innovative Power Products Couplers

- Welcome to the RF Cafe Website -

"Thinking like a customer is not too bad a way to design products." - Bob Pease, National Semi, Pease Porridge

Today in Science History

Tech Industry Headlines

Tech Industry Headlines - RF Cafe- Archive -

• Germany Mulls 5G ban for Huawei and ZTE

• SpaceX Sees Lower Orbit for Its 4,000+ Satellite Constellation

$775,000 Paid to Software Engineers Fired for Union Organizing

• Q3 Silicon Wafer Shipments Set New Quarterly Record

• Microsoft Resumes Rolling out Windows 10 October Update

Russia Jammed GPS During Major NATO Military Exercise

• U.S. FCC Orders Residents to Disconnect Security Camera Causing Harmful Interference

Women Leave Tech Jobs Because They Can't Climb the Ladder

Can We Stave off Radio-Frequency Super-Saturation?

Can We Stave Off Radio-Frequency Super-Saturation?, October 1967 Popular Electronics - RF CafeSpectrum crowding issues began almost as soon as wireless communications was started. Early spark transmitters spewed RF radiation all over the place, and (nearly) filterless receivers picked it up to convert the simple CW signals into dits and dahs from Morse code messages. As more people climbed onto the radio bandwagon with ever increasing transmitter power levels and receiver sensitivity levels, differentiating between desirable and undesirable signals became a frustrating task - like trying to hold a conversation in a room full of yakking people. Filters on transmitters and receivers provided much relief. User numbers continued to grow and phone (voice) communications, which occupies a few kilohertz of bandwidth instead of only a hundred or so Hz, started straining spectrum availability yet again. Newer modulation techniques like single sideband freed up some space, but then the digital age came along and started sucking up spectrum again. During the entire time, advances in electronic components ...

After Class: Understanding Decibels

After Class: Understanding Decibels, November 1958 Popular Electronics - RF CafeDecibels always have been and always will be a daunting subject to a lot of people. For electronics types, the issue of when to multiply the logarithm of the ratio by 10 or by 20 seems to be the biggest stumbling block. After many years of working with decibels, it becomes second nature. There are still instances, though, where I see seasoned engineers and technicians routinely confuse unreferenced decibel units (dB, the logarithm of a ratio) with logs of ratios referred to some base value (dBm, dBV, etc.). The bel unit was originally created to quantitatively assign changes in perceived levels of sound loudness...

'Buy American' Solution to Cyber Warfare by Chinese Spy Chips

'Buy American' Solution to Cyber Warfare by Chinese Spy Chips - RF Cafe"There's a serious cyber warfare problem that may be affecting some deployed U.S. military and aerospace mission-critical embedded computing systems, and nobody really wants to talk about it. It has to do with a computer chip no bigger than a grain of rice that's suspected of being installed by Chinese intelligence agencies on embedded servers made by San Jose, Calif.-based Super Micro Computer Inc. These tiny chips may be enabling China and other U.S. adversaries to monitor the inner workings of military computers and the data they are processing. Super Micro embedded computing servers are now, or in the past have been in use by some of the world's largest corporations, including Amazon and Apple. They also may now, or in the past have been in use ..."

Linear Scales Show Mixer Harmonics

Linear Scales Show Mixer Harmonics, January 10, 1964 Electronics Magazine - RF CafeHaving been out of the RF system design realm for a few years, I do not have much cause to think about mixer spurious products anymore. I wonder these days how many designers even do much in the way of frequency planning in conversion systems? Are the RF, IF, and baseband frequencies as so well defined for most of what is done in the wireless world that all the spurious product issues have been solved and there are few people who need to calculate mixer spurious product frequencies and powers? If there is a need, what methods are currently being used? Do you still cobble together spreadsheets and/or MATLAB worksheets using equations like those presented here, do you have a favorite smartphone app, a compact program on your computer, or are you using one of the two or three uber sophisticated and super expensive design engineering programs ...

San Francisco Circuits: PCB Fabrications & Assembly Service

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 ...

Electronic Components Printed Like Newspapers

Electronic Components Printed Like Newspapers - RF Cafe"The technique makes metals smoother and more flexible for better current flow throughout a metallic circuit. Cellphones, laptops, tablets, and many other electronics rely on their internal metallic circuits to process information at high speed. Current metal fabrication techniques tend to make these circuits by getting a thin rain of liquid metal drops to pass through a stencil mask in the shape of a circuit. But this technique generates metallic circuits with rough surfaces, causing electronic devices to heat up and drain their batteries faster. Future ultrafast devices also will require much smaller metal components, which calls for a higher resolution to make them at these nanoscale sizes. This requires molds with higher and higher definition ..."

Carl & Jerry: The Snow Machine

Carl & Jerry: The Snow Machine, December 1960 Popular Electronics - RF CafeWe are moving into the colder days of the year in the northern hemisphere. The normal high temperature here in Erie, Pennsylvania is around 49°F (35° today with snow on the ground for the last three days). It is the time of year that causes those less appreciative of cold weather to conjure up memories of warm summer days with green leaves on tree branches and colorful flowers in the garden. For those of you like me who actually prefer the cooler weather, this Carl & Jerry story about making snow by blasting clouds with ultrasonic energy just adds to my appreciation of the onset of winter and visions of a white Christmas. To date there has been no major, efficient progress in the field of snowmaking or rainmaking (other than seeding clouds with silver iodide). Ski resorts still need sub-freezing weather ...

Kenneth Kuhn's HP Museum

Kenneth Kuhn's HP Museum - RF CafePaul Rako posted a great piece on the Electronic Design website about University of Alabama professor Kenneth Kuhn's HP Museum. If you have a Pavlovian response at the mere mention of vintage HP test equipment, then you'd better put on a bib before visiting his website. Be sure to see the HP Tour page. Says the good prof, "This web site is devoted to the history of test equipment produced by the Hewlett-Packard Company which is now known as Agilent Technologies [Keysight by now - KRB]. I own a huge collection of vintage Hewlett-Packard test equipment, catalogs, equipment manuals, and Hewlett-Packard Journals. I also own probably one of the few still existing HP210A square wave generators ..."

Cable TV - Where It Is & Where It's Going

Cable TV - Where It Is & Where It's Going, January 1972 Popular Electronics - RF CafeAccording to this 1972 article in Popular Electronics magazine, cable television began around 1950. The system was very different that what we have nearly 70 years later. The familiar acronym CATV does not stand for CAble TeleVision, but rather Community Access TeleVision. CATV, as originally implemented, was a means of bringing broadcast TV to areas either too remote or too shielded from over-the-air (OTA) RF signals to provide good signal reception. Depending on the need, CATV could range from re-broadcasting of signals into targeted areas or sending signals through cable (originally unshielded) to individual homes. As you might expect, opponents of the new system predicted that such a scheme would eventually be the kiss of death for local broadcasters since large, well-funded conglomerates would be able to dominate programming selection and dry up advertising ...

Anatech Electronics Early November 2018 Product Update

Anatech Electronics Product Update November 13, 2018 - RF CafeAnatech Electronics, Inc. offers the industry's largest portfolio of high-performance standard and customized RF and microwave filters and filter-related products for military, commercial, aerospace and defense, and industrial applications up to 40 GHz. Anatech has introduced three new filter designs: a 1533 MHz cavity bandpass filter with SMA connectors, a 850 MHz LC bandstop notch filter with SMA connectors, and a 698-942/1710-2145 MHz single in/out duplexer filter with N-type connectors. Custom RF filters designs are used when a standard cannot be found, or the requirements are such that a custom approach is necessary ...

Alliance Test Equipment: Used & Refurbished, Purchase & Rental

Allied Test Equipment Products - RF CafeAlliance Test sells used / refurbished test equipment, we offer 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. Please visit Allied Test Equipment today to see how they can help your project ...

Griffith U. Precision Measurement Takes It to the Limit

Griffith U. Precision Measurement Takes It to the Limit - RF Cafe"Griffith University researchers have demonstrated a procedure for making precise measurements of speed, acceleration, material properties and even gravity waves possible, approaching the ultimate sensitivity allowed by laws of quantum physics. Published in Nature Communications, the work saw the Griffith team, led by Professor Geoff Pryde, working with photons (single particles of light) and using them to measure the extra distance travelled by the light beam, compared to its partner reference beam, as it went through the sample being measured - a thin crystal. The researchers combined three techniques - entanglement (a kind of quantum connection that can exist between the photons ..."

Satellite Electronics - Hugo Gernsback

Satellite Electronics, March 1958 Radio Electronics - RF CafeEcho 1 was put into orbit on August 12, 1960. This article was written 2½ years earlier in 1958 by Radio-Electronics editor Hugo Gernsback. A technology visionary and prolific inventor and writer, Mr. Gernsback astutely outlined the vast number of advantages that had already been and would in the future be afforded the science community by virtue of a satellite's perspective from space. Two of the Soviet Union's Sputnik satellites had revealed the surprisingly irregular shape and gravitational influence of the Earth, information about the upper atmosphere, and aspects of space environment effects on radio communications. America was scrambling to catch up. Gernsback and others postulated the configuration of active relay transceivers powered by solar cells and storage...

Anokiwave Appoints Alastair Upton as Sr. VP of Business Development

Anokiwave Appoints Alastair Upton as Senior VP of Business Development - RF CafeAnokiawave has found a good man in Alastair Upton. He was a highly respected and well-liked product line manager at RF Micro Devices when I worked there in the last decade. He was always appreciative of the competitor device teardown reports I wrote for him or for prying things open for him without breaking them. "Anokiwave, an innovative company providing highly integrated IC solutions for millimeter-wave markets and Active Antenna based solutions, today announced the appointment of Alastair Upton as Senior Vice President of Business Development. In this role, Upton will lead the company's strategic accounts, manage partnership programs, and provide telecommunications expertise to the company. This appointment comes at a strategic time for Anokiwave with tremendous opportunities for continued growth in the rapidly ..."

Six Possible Routes to Noninductive Tuned Circuitry

Six Possible Routes to Noninductive Tuned Circuitry, November 15, 1965 Electronics Magazine - RF CafeI remember in one of my circuits classes in college when the gyrator was introduced, and I thought it was an ingenious invention. The gyrator circuit, implemented with an opamp and a couple resistors and capacitors, changed its measured impedance type from that of a capacitance to that of an inductance. That is, its impedance represents an R + jX  Ω format. Frequency limits are imposed by a combination of the self-resonant frequencies of the resistors and capacitors as well as the gain-bandwidth product of the opamp, and power handling is primarily limited by the opamp's voltage and current capabilities. You might ask why, with all those constraints on its use you would even want to use a gyrator circuit? The answer is that within its limitations, the gyrator often represents a less expensive and more compact version of a physical inductor ...

15 Ways Life Was Different Before the Internet

15 Ways Life Was Different Before the Internet - RF CafeThe convenience and awesome power of the Internet has for practical purposes always existed for anyone born in the 1990s or later. Having been a teenager in the relatively prehistoric 1970s, the possibility of smartphones and cars run by microprocessors was the domain of Mechanix Illustrated magazine visionaries who also dreamed up flying cars, personal nuclear power generators, and a pill to cure the common cold. Nothing that would come to fruition in my lifetime - right? Sure, this is just yet one more person's nostalgic waxing about olden times before the Internet was, but go ahead and take a look. It all strikes a familiar chord with me ...

VidaRF: Passive RF & Microwave Components

vidaRF passive RF & microwave components - RF CafeAt VidaRF, the phrase 'Providing Simple Solutions for Complex Connections' is more than just a slogan – it's a mindset, a mission, and a driving force behind everything we do. Their pledge is to design and distribute high performance, cost effective RF Microwave products to fit each customer's unique applications. Please visit VidaRF today to see how their lines of attenuators & terminations, directional couplers, power dividers, coaxial connectors, and circulator & isolators can be of use to your project. "When the standard just will not do, VidaRF has the solution for you!" ...

Taking Stock of mm-Wave Activity Ahead of FCC Auction

Taking Stock of mm-Wave Activity Ahead of FCC Auction - RF Cafe"FCC has already allocated 12.55 gigahertz of millimeter wave spectrum. Millimeter wave spectrum is key to delivering on the ultra-high throughput speeds associated with 5G. In the U.S., the Federal Communications Commission is gearing up auction 28 GHz and 24 GHz licenses on Nov. 14, and domestic operators AT&T and Verizon are launching their first 5G services using the 39 GHz and 28 GHz bands respectively. This momentum, coupled with other regulator-led activity in key global markets, highlights the fundamental role of millimeter wave in 5G. In Europe, U.K. officials plan to allocate 26.5 GHz to 27.5 GHz in the 2020 timeframe as do their counterparts in Spain, Austria ..."

Mac's Radio Service Shop: Barney is a Big Boy Now

Mac's Radio Service Shop: Barney is a Big Boy Now, January 1949 Radio & Television News - RF CafeDon't let the title fool you. This is not a "bees-birds-and-flowers routine" being provided to Barney by his boss, Mac. It turns out to be a brief introduction into the fine art of troubleshooting intermittent problems in radio and television circuits. As is usually the case, while the specifics of the scenarios Mac describes might not apply to your challenge at hand, the general philosophy always does. It is basically the old process of elimination where after rapping components mechanically and/or heating or cooling them in hopes of observing a tell-tale change in performance, the next step is to divide the suspected circuit portion in half (electrically, but sometimes also physically) and look in one direction. If the problem ...

Author: Kirt Blattenberger on Google+ Author:
Kirt Blattenberger

ERZIA (RF amplifiers, wireless, communications) - RF Cafe Rohde & Schwarz RTB2000 Digital Oscilloscope - RF Cafe
QuinStar - RF Cafe Antenna Test Lab - RF Cafe
About RF Cafe
Kirt Blattenberger - RF Cafe Webmaster
Copyright: 1996 - 2018
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 Internet was still largely an unknown entity at the time and not much was available in the form of WYSIWYG ...

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

spacer