RF Cafe Software
About RF Cafe
1996 - 2022
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:
Try Using SEARCH
to Find What You Need.
There are 1,000s of Pages Indexed on RF Cafe !
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.
Homepage Archive Pages
2017: Jan |
Jun | Jul |
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
Here is page 1 of the April 2015 homepage archive.
Handheld Digital SMD Tester
This handheld digital SMD tester is a handy tools for quickly measuring surface mount component values. Unlike the old days of huge resistors, capacitors, and inductors that had plenty of space on their packages for markings, the grain-of-salt-size devices on modern day circuit boards defy identification once removed from their shipping containers. The added expense of laser marking makes doing so for every component highly impractical. If you have ever tried to use a standard set of multimeter probes to measure even a 1206 size resistor, then you know what a pain it can be, and then being sure that enough pressure is being …
Mac's Radio Service Shop:
Intermittents Still Pursue
Mac McGregor, owner of Mac's Radio Service Shop, can always be counted on to provide his apprentice technician, Barney, with a lesson from his own life-long attendance at the School of Hard Knocks. Barney is your stereotypical young buck whose level of seriousness needs occasional alignment, just as do the radio and television sets he services. In this episode, I can't find where Mac actually solved the intermittent electrical condition believed to be causing the problem - weird. The "Mac's Radio Service Shop" series ran in Radio & Television News magazine for many years …
EDI CON China 2015 Sets
Record for Attendance
Horizon House Publications and Microwave Journal China are pleased to announce that 2625 total attendees visited EDI CON China 2015 in Beijing, April 14-16, at the China National Convention Center (CNCC), significantly exceeding the previous two years attendance numbers. This included 1214 delegates attending the conference and exhibition. The plenary session drew close to 300 attendees with about 350 attending the Keysight sponsored reception dinner. The exhibition contained close to 100 companies occupying 1300 square meters in floor space. EDI CON China has grown each year since its start in 2013 establishing itself as the leading RF/microwave, high-speed digital and EMC/EMI …
Pasternack Log Video Amps
with Broadband to 18 GHz
Pasternack, a leading manufacturer and supplier of RF, microwave and millimeter wave products, introduces an all new line of broadband log video amplifiers covering multi-octave bandwidths from 0.5 GHz to 18 GHz. The 5 models being released include 4 Successive Detection Log Video Amplifiers (SDLVA), and 1 Detector Log Video Amplifier (DLVA), which offer a wide input dynamic range, high signal sensitivity, fast recovery times, and excellent temperature stability. Pasternack’s log amplifiers are used to measure widely varying signals at high frequencies in applications where rapid and …
Electronic Mixer Control Repair:
My Part to Reduce E-Waste
Just because I don't wear Earth Day or 'Save the Whales' T-shirts or donate to their causes does not mean that I abide wanton and senseless destruction of our planet's resources and natural beauty. Do a search of RF Cafe and you will find many examples of articles I have written and headlines posted regarding offenders and, equally as important, the hypocrisy … My latest example of repair is a Braun kitchen hand mixer that we've had for at least two decades. The blue heat shrink tubing on the power cord was part of a repair done many years ago. Recently, Melanie reported that the multi-speed switch seemed to be intermittent. After confirming the symptom, I opened the case and removed the switch assembly. Fortunately, it was held together with locking …
The Oscilloscope Applied
to Transmitter Checking
Being able to quickly interpret oscilloscope waveforms is essential to efficient circuit design, adjustment, and troubleshooting. Knowing tell-tale signatures of signal-corrupting influences from unintended resistance, capacitance, inductance, and nonlinear (semiconductors and vacuum tubes) is a huge advantage when using an o-scope. Equally important is not introducing waveform- and function-altering effects with probing techniques and/or incorrect operation of the test equipment. One often seen example of the latter is using equipment whose input impedance is not proper for the unit under test (UUT); e.g., wring impedance coaxial cable in RF situations or too low of an input impedance for low frequency applications that …
Rubik's Cube Solution Time
Record: 5.253 Seconds
Did you see the video of the kid who just set a new Rubik's Cube solution time record? Collin Burns unscrambled Hungarian architect Erno Rubik's 3x3x3 cube in a mere 5.253 seconds per the CubeComps website record list. It is an amazing spectacle to see. Formal rules are set by the World Cube Association (WCA) for other format cubes like the 2x2x2, the 4x4x4 and the 5x5x5. My first thought when watching the video is was how scrambling of the cube was randomized to assure fairness in unscrambling times? It turns out that the WCA provides a program for setting start patterns, which must be used for official …
Smart Watch for Android
LeFun One Bluetooth Phone Smart Watch wrist phone with NFC. Mates with Android phones like Samsung S3/S4/S5/Note 2/Note 3/Note 4 HTC Sony LG and iPhone 5/5C/5S/6/6. Unlike the Apple Watch, this model is capable of functioning as a stand-alone cellphone with a SIM card installed. You can send and read texts, make or receive calls on your watch, like a GSM cell phone. With a SIM card, it works as a cell phone companion, receiving and making calls, getting texts via Bluetooth. Unlike that 'other' watch priced at $349, Android smart watches can be bought for under $75.
Empower RF & Advanced Test
Equipment Rental Partnership
Advanced Test Equipment Rentals (ATEC) and Empower RF Systems today announced an agreement to become a preferred rental distributor of Empower RF’s high power amplifiers for EMC compliance and product testing applications, bringing greater product availability to customers with immediate test equipment needs. ATEC will now carry the Empower Next Generation Platform of RF amplifiers, including the 1 to 3.1 GHz, 1 kW HPA, model 2170, which is ideal for Automotive and DO-160 pulsed and CW immunity requirements …
Slide Rule Calculators
Donated by Gary Steinhour
Many thanks to website visitor and contributor Gary Steinhour for donating three new cardboard slide rule calculators to the RF Cafe museum! The Ballentine Rule performs the following: dB ↔ Ratio Conversion | Volts ↔ dB Power Level, EM Labs' slide rule performs: U.S. ↔ Metric Conversions, and Tel-Instrument's slide rule performs: AC Power.
Cobham's DAS Antenna Range
Now Available on iBwave
The DAS antenna range has been designed to provide excellent and consistent performance. At the same time providing the opportunity for cost savings to installers and operators. A Distributed Antenna System (DAS), consists of a network of antennas that are connected to a common source which is able to provide wireless and radio coverage throughout buildings, terminals and open areas. The need for a system to support the changing face of mobile communications has been prompted by increasing use of mobile devices including phones, laptops, tablets and ‘Smart’ machinery …
Acoustinators & Wobbulators
Radio Service Data Sheets
you do a search for "acoustinator,"
you get a certain model of acoustic guitar speaker manufactured by the UK-based company, Eminence. That, however,
is not the same as the "Acoustinator" developed by Motorola for their "Golden
Voice" series of car radios. It was essentially what we refer today to as a tone control, or as an equalizer.
Not satisfied with creating just one futuristic sounding techno-term, Motorola also came up with the 'wobbulator'
for use in tuning the receiver IF response …
I also posted the Radio Service Data Sheet for the General Electric Model HJ-1205 console floor model radio …
Notable Quote on the
Future of Missile Mail
"Before man reaches the moon, mail will be delivered within hours from New York to California, to England, to India or to Australia by guided missiles." - Arthur Summerfield, U.S. Postmaster General. On June 8, 1959, in a move that PG Summerfield heralded as "of historic significance to the peoples of the entire world," the Navy submarine USS Barbero fired a guided missile carrying 3,000 letters towards the naval auxiliary air station in Mayport, Florida. Racing along at about 600 miles per hour, the guided missile traveled the more than 100 miles from the deck of the submarine off the coast of Florida to the air station in about 22 minutes …
The Aircraft Radio Serviceman
Aircraft electronics has always been on the bleeding edge of technology because of the ever-increasing need to fly in the widest range of atmospheric conditions possible. Accordingly, skills needed by avionics servicemen are amongst the highest required in any electronics field. There are still many pieces of vintage equipment in service that need to be maintained, but even 20- to 30-year-old airborne radars and navigational units require top-notch techs to troubleshoot and align. One topic in particular that plagues electronics operation even in modern airframes is that of static electricity build-up and lightning strikes. We all face those kinds of static discharge hazards in non-aviation environments, but for the most part a failure on the ground or water is not as imminently …
Google "Matched Content"
Google very recently began a Beta test program called "Matched Content," where 'related' pages within the website are displayed in a scrollable banner format. Hyperlinks to the pages are provided. I just installed it yesterday and it seems to be working very well. The format is very colorful and attractive as you can see by a screen capture below (and a 'live' version at the bottom of the page). Part of Google's Page Rank algorithm gives credit for cross-linking to other related pages within your own website, so I wonder whether this counts, as opposed to actually placing internal hyperlinks within the page content; it would be nice if it does. Google is limiting the Beta to …
Please Welcome Saelig Co.
as a New Advertiser!
Saelig Company, Inc. (bottom 728x90-pixel banner ad) is a New York State corporation operating as a Sales and Marketing Agent and Distributor for more than 100 manufacturers from all over the world. Founded in 1988 by Alan Lowne, Saelig has earned a growing reputation for having notable products not found elsewhere. “Saelig” is an Olde English word which means “happy, prosperous, blessed”. We sell and support a wide range of electronic control and instrumentation equipment and components to customers ranging from Fortune 500 industrial users, military, educational institutions and hospitals to individual end-users …
NI AWR Software Showcased During IMS2015
NI (formerly AWR Corp), showcases NNI AWR software throughout the International Microwave Symposium 2015 (IMS2015) in a number of ways. A preview of V12 NI AWR Design Environment™ software, including new load-pull and antenna features, as well as ease of use, speed enhancements and third-party integration flows, will be on display inside NI booth #2431. IMS2015 runs from May 17-22 in Phoenix. NI AWR Software Demonstrations What’s New in V12 –preview the new features in the upcoming V12 release of the NI AWR Design Environment and you’ll be entered into our GoPro raffle …
Decibel Level vs. Decibel Gain
Arithmophobia (a real word) is likely the root cause of of decibelphobia (that one's made up), a condition that causes some otherwise rational people to curl in the fetal position in an attempt to avoid the topic. As with most subjects, the more often you engage in using a term, the more comfortable you become with it. Technicians and engineers who deal in voltage and power levels in terms of dividing quantities or transmitting them from one location to another would find conversation and writing without the use of decibels quite inconvenient. It is tempting to point out that using decibel units to express ratios or relative levels, thereby permitting use of simple addition and subtraction rather than multiplication and division, respectively, is no different than using logarithms to…
Radio Amateur Course
-Vacuum Tubes -
Just the other day I was using the familiar analogy that relates water pressure, hose diameter, and flow rate to electrical voltage, resistance, and current, respectively, in an explanation to my daughter regarding why the water flow rate in her rebuilt house (original burned down a year ago) is not what it was in her original house. The cause, I surmise, is due to use of the plastic PEX tubing which has a smaller inside diameter than the old copper pipe. The submersible pump and holding tank supply the same 50 psi as before, but since that pressure now has to force the water through a path inside the house that has more resistance to the water flow, the delivery rate to fixtures is now lower. When I hold the contacts closed on …
Empower RF Conducting Live
Demos at MTT-S IMS 2015
Empower RF Systems is once again conducting live demonstrations of broadband, high power amplifiers with compelling performance, industry leading small size, and user interface / functionality that dares to challenge legacy products offered in the market. Next appearing at MTT-S IMS 2015 in Phoenix, AZ, we will be showcasing our 1 to 3 GHz, 1 kW HPA in a 5U chassis. This is an extraordinary design which includes an integrated (internal) dual directional coupler and instrument …
A New Crop of RF & Microwave
Articles is Ready
A new crop of articles on RF and microwave topics has been posted online by our industry's contemporary magazine publishers. Just as the hard copies arrive in our mailboxes at different times each month, so too do the online versions. We are treated to the usual mix of narrowly focused expositions on specific applications like "Compact Microstrip Lowpass Filter with Ultra-Wide Stopband Using a Modified Circular Resonator," as contrasted to ones covering broader subjects such as "Cut the Defense Budget? Sure, No Worries." A general rule of thumb seems to be the longer the title, the more specific the article. They're all worth reading, but alas, busy schedules limit most of us …
Saelig Introduces Pre-
Compliance EMC Probe Kits
Saelig Company, Inc. announces the availability of the TBPS01-TBWA2 EMC Probe Kit, which includes investigative near-field probes and a wideband amplifier to increase the versatility of economical spectrum analyzers to identify EMC issues. The economical TBPS01-TBWA2 EMC Probe Kit consists of four rubber-handled near-field probes (three H-field and one E-field), a 20 dB or a 40 dB wideband amplifier, and associated cables, supplied in an attractive wooden case. The shielded probes have built-in ferrites and insulated rubber handles to insure that measurements are insensitive to the human hand. The H- or E-field probes are useful for detecting radiated …
The Electrician's Trade
Demystified! - A Review by Moi
The Electrician's Trade Demystified!, by David Herres, is, per the cover's claim, "Everything an aspiring electrician NEEDS to KNOW." That is a pretty bold claim for a book of 250 pages when considering how wide AND deep the field of electrical tradesmanship really is. However, because of the way in which David approaches the subject, I am convinced that within reasonable constraints of expectations, the book does an excellent job at informing an aspiring electrician with everything he needs to know. How can I corroborate the assertion, you might ask? Simple. There is no attempt to cover every chapter word by word or to impart a comprehensive knowledge of every topic to the reader. Instead, all chapters are addressed in terms of what kind of material is contained, how it is arranged, what material should be memorized by every electrician, and how the table of contents and …
Send Me Your Press Releases!
There is a very easy - and FREE - way for you to get your company's products and services in front of RF Cafe visitors: Press Releases. Serving between 7,000 and 10,000 pages each weekday provides a valuable amount of exposure to people like you - serious engineers, technicians, students, and hobbyists. If your company makes products that I deem relevant to my readership, I will gladly post your press release, company news, product announcements, etc. Please send the information, along with images (or links to online images), hyperlinks to featured product pages, contact information, an About Us statement, and other such content usually associated with press releases. I do …
Anatech's April Newsletter
Anatech Electronics, a manufacturer of RF and microwave filters, has published its April 2015 newsletter. As always, it includes both company news and some tidbits about relevant industry happenings. This month, Sam Benzacar reports on the progress of the worldwide LTE rollout, the status of VoLTE (Voice over LTE ), and the DoD's efforts to reduce the cost of electronic systems acquisition (particularly EW). He also discusses how to handle a growing number of frequency bands that need to be accommodated by cell tower base stations …
RF and Microwave Engineering:
Fundamentals Wireless Comms
RF and Microwave Engineering: Fundamentals of Wireless Communications, by Frank Gustrau, discusses a wide range of RF topics with emphasis on physical aspects, including EM and voltage waves, transmission lines, passive circuits, antennas. New coverage includes the consistent use of modern RF tools such as RF circuit simulation, EM simulation, computerized smith chart in various examples that show how the methods can be applied productively in RF engineering practice. Examples that illustrate the theoretical parts are close to real world problems, so readers can directly use the methods in their own work context …
Fairview Unveils New Portfolio
of Electromech Relay Switches
Fairview Microwave, a supplier of on-demand microwave and RF components, debuts a completely new portfolio of electromechanical relay switches that cover ultra-broadband and millimeter-wave frequencies up to 40 GHz. These high-reliability coaxial RF switches are guaranteed to perform up to 2 to 10 million life cycles, which make them an ideal solution for demanding industries and applications related to defense and commercial aviation, radar, wireless communications, satellite communications, test and measurement and many …
Here are a couple more comics from magazines of the days of yore. Radio-Craft readers submitted ideas for funnies and then artist Frank Beaven would draw the comics based on their ideas. Some months had no comics, and some had as many as half a dozen. This month had two. There is also one from the May 1946 Radio News. Enjoy.
Notable Tech Quote
RFCafe.sucks Domain Available
"I told my people the best way not to get included is not to suck." he says. New .Sucks Internet Domain: Extortion Or Free Speech? - J. Scott Evans, associate general counsel at Adobe Systems, in response to whether his company would succumb to what some consider extortion with the issuance of ".sucks" domain extensions. The extension, which some malicious SOP (son-of-a-pup) with too much money to spend could use to buy "RFCafe.sucks," would cost as much as $2,500 per year.
Crossword Puzzle from
a 1963 Electronics World
This crossword puzzle appeared in the October 1963 edition of Electronics World. About half the words used are related directly in some way to electronics or physics. My RF Cafe crosswords, BTW, have 100% of the words directly related to the sciences. Enjoy.
A Corporation as an Expert
Witness? IMS ExpertServices
IMS ExpertServices periodically sends me e-mails that highlight recent key court cases that can significantly affect the effectiveness of expert testimony, both for the plaintiff and for the defendant.
This article by attorney Joshua Fruchter, writing for IMS ExpertServices, reports on a case where the defendant sought to declare a corporation as a qualified 'expert' witness, thereby hoping to draw on the collective authority of an entire pool of knowledge that would be, if permitted, virtually unassailable. Since the plaintiff was an individual, surely his personal credentials could not approach that of a pool of professionals at a public corporation employing maybe thousands. It would be like me challenging the electrical engineering department staff at MIT about the precision of the value of a charge on an electron. Interestingly, …
Lafayette Chassis Model B-100
Radio Service Data Sheet
The Radio Service Data Sheets that were published in Radio-Craft usually seem to have more information included than those published in other magazine, at least in the same era (1940-ish). It might have to do with how much material is provided by the manufacturer rather than a decision by the magazine editors. Anyway, here are the schematics, chassis layout, and service info for the Lafayette Model B-100 through B-103. Believe it or not, there are still people searching for such data.
Example Engineer's Resumes:
Career and Job Advice
This week's collection of engineering career advice articles includes a few sample resumes as provided by Kim Isaacs, the 'resume expert' at Monster. Having been out of the job search market myself for over a decade, I don't even know what is expected anymore, but Ms. Isaacs believes that she does (and she's probably right).. As always, caveat emptor when heeding advice - especially potentially life changing advice - from strangers.
NI AWR App Note Load-Pull for
Design of WB High-Efficiency PA
NI (formerly AWR Corporation) announces a new application note titled “Using NI AWR Design Environment Load-Pull Simulation for the Designer of Wideband High-Efficiency PAs” that explores the design of PAs leveraging load-pull technology within NI AWR Design Environment™ software, specifically that of Microwave Office. Using a Cree CGH40010F gallium nitride high-electron mobility transistor in a Class F PA at 2000 MHz as the example circuit, the application note details how power-added efficiency is maximized by optimizing source and load pull at the fundamental frequency, plus second and third …
When Popular Electronics began publication in October of 1954, its editors included both radio control modeling and amateur radio as regular features. The magazine's target audience was made up of professional, student, and hobbyist electronics aficionados who often mixed their interest in electronics with another hobby; e.g., the aforementioned R/C and Ham radio, but also counted amongst readers were audiophiles looking for top-notch systems, do-it-yourselfer (DIY) domestic gadget makers, and automotive enthusiasts. It might seem like today there is not as much interest in such endeavors as in times past, but the plethora of hobby type magazines still being published in hard copy, electronically, …
MECA Electronics Intros
Low PIM 10 Watt Terminations
Featuring our NEW (line) of 10 Watt Low-PIM Terminations, with industry leading performance of:
* -175 dBc Typical to <-165 dBc
(2 x 5 Watt)
* -165 dBc Typical to <-155 dBc
(2x20 Watt tones, additional
heat sink required), while
handling full rated power to
* All Terminations cover
380 MHz to 2.700 GHz
* VSWR = 1.10:1 Typ / 1.20:1
Max. (0.698-2.700 GHz)
* VSWR=1.15:1 Typ / 1.25:1
Max. (0.380-0.698 GHz)
* 7/16 DIN, Type N, & 4.1/9.5
Crosley Radio Advertisement
Commercially available radio receivers for the home had only been around for a couple decades when this advertisement from Crosley appeared. I keep looking in old electronics magazines for an ad featuring my 1941 Crosley model 03CB console radio, but thus far with no luck. What makes it special is that it was probably one of the last new radios sold prior to the shift of material usage to military equipment in World War II.
Radar Scores SAC Bombing Test
Most people have heard of the incredibly accurate Norden bombsight that was credited for revolutionizing accuracy of heavy bombers like B-17s, B-25s, 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, the Norden had been replaced by radar-integrated bombing systems. Additionally, ground-based radar measurement systems were …
littleBits™ Modular System
Electronic Building Components
Steve Ford had a little bit about littleBits™ in his "Eclectic Technology" column in the April issue of QST, and it looked interesting enough to mention here. "What is littleBits? littleBits makes an opensource library of electronic modules that snap together with tiny magnets for prototyping, learning, and fun. littleBits consists of tiny circuit-boards with specific functions engineered to snap together with magnets. No soldering, no wiring, no programming, just snap together for prototyping, learning and fun. Each bit has a specific function (light, sound, sensors, buttons, thresholds, pulse, motors, etc), and modules snap to make larger circuits. Just as LEGO …
Skyworks Intros 8 Low Noise
Variable Gain Receive Modules
Skyworks introduces eight low noise, variable gain receive modules for LTE and WCDMA infrastructure applications requiring low noise and high linearity. The SKY65369-11, SKY65370-11, SKY65371-11, SKY65372-11, SKY65373-11, SKY65374-11, SKY65375-11, and SKY65376-11, which are ideal for all wireless infrastructure OEMs and ODMs, are low noise, highly linear VGA modules that operate in the 700 to 2600 MHz range and feature very low return loss. The fully integrated high performance devices replace …