•−•  ••−•    −•−•  •−  ••−•  •
RF Cafe Morse Code >Hear It<

Job Board

About RF Cafe™


    - RF Cafe Homepage -
     RF, Microwave, Wireless, Cellular, Radar, Satellite, & Analog Engineering

Today in History

Tech Headline News

-  Archives -

Blackberry Classic Goes 'Back to Company's Roots'

Investment in Equipment Grows As U.S. Manufacturing Booms

Modern Alchemy: Turning Hydrogen into 'Graphene?'

Barclaycard Tests Contactless Payment Gloves (I hereby claim the Michael Jackson NFC glove design)

ESA Astronaut Samantha Cristoforetti, IZ0UDF, Conducts 1st ARISS School Contact

'Bullet-Looking Missile Thing' Turns Heads Along Highway South of Boulder

Vote for the 'Engineer of the Year'

The Myth Called "Ground"

Successful Tech Requires Old-Fashioned Skill: Organizing People

LTE TDD - What Comes Next?

American Airlines to Add Inflight Internet Access to Nearly 250 Regional Jets

Tunable Photon-Pair Spectrum Using RT Quantum Optics Silicon Chip

Future Batteries: Lithium-Sulfur with Graphene Wrapper

U.S. Preps to Increase Number of High Tech Work Visas in 2015 Due to Claimed Shortage (oh, how I despise these elected cretins)

Your All-Electric Car May Not Be So Green

Reshoring Will Continue as U.S. Manufacturing Booms in 2015 (let us hope so)

A Short Course in
Practical Electronics

A Short Course in Practical Electronics, April 1944 Radio Craft - RF CafeThe probability-based quantum mechanical model of atoms has been in existence since around 1932 when Robert Mulliken coined the term 'electron orbital.' It superseded the Bohr model that modeled the atom as a proton / neutron nucleus that was surrounded by electrons orbiting like planets around a star. For many decades thereafter, text books - particularly those used in beginner level courses - continued to present the Bohr model and only gave passing reference, if at all, to the quantum model. The Bohr model was and still is easier for most people to envision, although as time goes on the percentage of people who even recognize a planetary model is probably rapidly decreasing

Engineering Career News & Tips
for December 12, 2014

Engineering Career News & Tips for December 12, 2014 (hasslefreeclipart.com) - RF CafeThis week's collection of career-related articles starts out with on that cites reasons why overly - and overtly - nice people might not be the most trustworthy amongst your employees / co-workers. It will probably come as no surprise to anyone that "New research suggests habitually pleasant people may not be as deserving of your trust as their more curmudgeonly counterparts." Then again, research papers tend to have the nasty habit of producing results sought after by their authors, particularly if a 'shock factor' can be generated. You'll also be treated to some

- Why the Nicest People Make
   Bad Employees
- Tell-Tale Signs Your Boss
   Doesn't Like You
- How to Answer 'Tell Me About
   Yourself' in Interview <more>

More Free Engineering
Magazine Subscriptions

December 2014 Free Engineering Magazine Subscriptions - RF CafeWouldn't it be nice if you could get a free subscription to your favorite cycling, fishing, or camping magazine merely by demonstrating that you have a vested interest in the subject that advertisers can exploit? Don't be looking for a year's worth of Sports Illustrated, Field & Stream, or Handyman to arrive in your mailbox anytime soon (unless some kind soul gives you a subscription), but you can, if you are qualified, received complimentary subscriptions to many of the big-time engineering magazines. Here are just a few of what is available

Author: Kirt Blattenberger on Google+ Author:
Kirt Blattenberger

ET Industries Intros
10-50 GHz Power Divider

ET Industries Intros 10-50 GHz Power Divider - RF CafeET Industries is a leader in the design of high frequency, wideband Power Dividers. Model D-1050-2 is a 2 way power divider spanning 10-50 GHz. The maximum insertion loss is less than 1.80 dB. Amplitude balance is 0.5db maximum and phase balance is 5 degrees maximum. The minimum isolation is 16 dB and VSWR is 1.70:1 maximum. Connectors are 2.4 mm female. Housing size is 1.15" x 1.06" x 0.5".

Anatech Electronics'
December 2014 Newsletter

Anatech Electronics Newsletter for December 2014 - RF CafeAnatech Electronics, a manufacturer of RF and microwave filters, has published its December 2014 newsletter. As always, it includes both company news and some tidbits about relevant industry happenings. This month, Sam Benzacar looks into his crystal ball and dares to predict the RF / microwave market's future for defense, the wireless industry, the Internet of Things (IoT), Wi-Fi, and industry, medical, and scientific applications in 2015. Sam has been in the business of designing and selling filters for all these industries for a long

Notable Tech Quote

War Comes, January 1942 QST - RF Cafe"...Nature is no respecter of military emergencies." - K.B. Warner, W1EH, in the January 1942 issue of QST magazine, regarding the Federal Communication Commission (FCC) decree suspending indefinitely all amateur radio activities in the U.S. following the December 7, 1941 attack on Pearl Harbor. Read the complete "War Comes!" article.

Empower RF Systems Intros
1-3 GHz, 1 kW Power Amplifier

Empower RF Systems Intros 1-3 GHz, 1 kW Power Amplifier - RF CafeEmpower is pleased to be releasing additional, industry leading power amplifier models that compliment the frequency coverage and power level "footprint" of our next generation, high power PA product family. Model 2170, covering 1 to 3 GHz and delivering 1 kW of broadband output power in a 5U, air cooled chassis is our latest market release. Offering unrivaled size / power advantages and building on a design architecture that has been a catalyst for technology upgrades from customers with diverse requirements from multiple markets, Model 2170 provides excellent performance for

Werbel Microwave Intros
2-18 GHz Directional Coupler

Werbel Microwave Intros 2-18 GHz Directional Coupler - RF CafeNew directional coupler from Werbel Microwave covers 2-18 GHz continuously at 10 ±1.00 dB. Made in the USA from domestic materials. Return loss is specified at -14 dB or better, directivity specified at 15 dB min (up to 12.4 GHz, -12 dB above 12.4 GHz). Ready for immediate production. Order now!

How the V-2 Rocket
Was Wirelessly Controlled

How the V-2 Rocket Is Wirelessly Controlled, April 1945 Radio News - RF CafeHere I go again saying how Germany missed an opportunity - twice - to be the world's technical superpower by starting wars that numerically proved it could never win. Scientists and engineers of Deutschland designed and implemented what would be the first wirelessly guided missile for correcting the flight path of the V-2 rocket (the 'V' stood for Vergeltungswaffe, or vengeance weapon). This article from a 1945 edition of Radio News describes how a radio 'cone' was formed by a ground-based transmitter array that caused an airborne guidance system to keep the rocket on course during the boost phase of its flight. Embarrassingly, I don't recall

General Electric Model 7-4305C
Roll-Down Number Clock Radio

General Electric Model 7-4305C Flip-Number Clock Radio - RF CafeYou know by now if you have visited RF Cafe a few times that I like to collect and restore vintage electronics and mechanical items that can be put to use - as opposed to just accumulating stuff and never using it for anything (although, admittedly, I do a bit of that as waell). Since I don't do it for the collector's value, most items, if they are not already in good condition, get reworked until they look as new as possible - and work. Some 'experts' would admonish me to leave the items with their original paint, varnish, metal and wood parts, etc., and never do anything that would destroy its authenticity. If I ever happen to acquire a Rembrandt or a Stradivarius, I'll be sure

Z-Comm Intros Low Noise VCO
for Low Cost Basestations

Z-Comm Intros Low Noise VCO for Low Cost Basestations - RF CafeZ-Communications, Inc. announces a new RoHS compliant VCO model CRO2273B-LF. The CRO2273B-LF operates at 2265 to 2280 MHz with a tuning voltage range of 0.5 to 4.5 Vdc. This high performance VCO features a spectrally clean signal of -115 dBc/Hz @ 10 kHz offset and covers the band with a typical tuning sensitivity of 4 MHz/V. The CRO2273B-LF is designed to deliver +3 dBm of nominal output power into a 50Ω load while operating off a 5 Vdc supply and drawing typically 20 mA of current. This low noise

Nothing Says "It's Christmas"
Like an Iotatronized LED Tree

Velleman MK130 3D Xmas Tree - RF CafeFor a mere $10 you can own this iotatronized, blinking LED Christmas tree for wow your co-workers. It comes as a kit and needs a 9V iotatron battery to act as both the power supply and a weighted base. Velleman has a lot of simple, inexpensive, build it yourself electronic kits. Hurry - there are only seven shopping days left 'til Christmas!

Transistor Invention
Announced 67 Years Ago Today

Transistor Trends: 67th Birthday, May 1958 Radio-Electronics - RF CafeIf you are reading this, then chances are you owe a part of your livelihood to three gentlemen by the names of Bardeen, Brattain and Shockley. On this day 66 years ago the trio announced their discovery of a gain producing semiconductor device that they dubbed a 'transistor' due to its dual nature as a transconductance amplifier and a variable resistance. This article by magazine editor Hugo Gernsback, in celebrating the 10-year anniversary of the transistor, mentions that somewhere in the neighborhood of 30 million of the little miracle components would be sold that year. The microprocessor in the device you are using to read this contains more than a billion. By comparison, the 'primitive' year-2000-vintage Intel Pentium 4 itself integrated

America's Next Great Industry
- Television - Is Ready

America's Next Great Industry - Television - is Ready, January 1945 Radio News - RF CafeBy 1945 everyone of importance in the electronics industry was blowing the figurative horn of television. The country would transform from "a chicken in every pot" to "a TV in every living room" (OK, I just made that up). The NTSC had set the standards for transmission, but hardware implementation was by no means agreed upon. If my memory is correct, there were still some manufacturers clinging to the mechanical spinning disc with a projection screen rather than using electronic circuits and a CRT. Entire industries - not only electronics - were bursting at the seams in anticipation of the war ending and being allowed

Wright Brothers Crossword

Wright Brothers Crossword Puzzle for December 14, 2014 - RF Cafe111 years ago this week (December 17, 1903), Orville and Wilbur Wright made their historic first flight whereby a human and aircraft took off and flew under its own power. The Wright Flyer, piloted by Orville, took off from rails on a dune at Kill Devil Hills, NC, and Wright Flyer crossword - RF Caferemained airborne for 120 feet before landing on the beach below. The location was chosen for the orographic lift generated by the ocean winds blowing up the sandy slopes. This week's crossword commemorates the event by incorporating many relevant terms and clues. Enjoy!

RF Cafe Quiz: Space-Time
Adaptive Processing for Radar

RF Cafe Quiz #64: Space-Time Adaptive Processing for RadarThis quiz is based on the information presented in Space-Time Adaptive Processing for Radar, by J. R. Guerci. Note: Some of these books are available as prizes in the monthly RF Cafe Giveaway "Space-time adaptive processing (STAP) is an exciting technology for advanced radar systems that allows for significant performance enhancements over conventional approaches. Based on a time-tested course taught in industry, government and academia, this second edition reviews basic STAP concepts and methods, placing emphasis on implementation in real-world systems. It addresses the needs of radar engineers who are

Army Radio Communications

Army Radio Communications, May 1945 Radio Craft - RF Cafe

Seamless integration of wireless communications with wired communications has not always been a yawn in technical strategy discussions. It has really only been since the early 1990s with the introduction of ubiquitous cellphone systems that someone on a wireless device could connect directly with a wired (i.e., landline) contact and not need an intermediary operator to facilitate. Some military systems, the Inmarsat system and a few other proprietary systems were available, but not to the public at large. This article reports on some of the Army's early attempts at implementing wireless-to-wired communications. Unlike present day systems that rely heavily

Court-Appointed Experts:
The Future of Litigation?

Court-Appointed Experts: The Future of Litigation? IMS ExpertServices - RF CafeThe good folks at IMS ExpertServices have published an interesting short article highlighting the increasingly difficult technical issues being brought before courts in intellectual property (IP) cases, Court-Appointed Experts: The Future of Litigation? - RF Cafeand an inability by judges to render informed opinions based on evidence presented. Attorney Ryan Thompson addresses the issue in a case involving Silk Road and its use of Bitcoin payments to remain 'under the radar' of law enforcement for nearly two years. While there are some amazingly intelligent jurists in the courts, expecting any one person to possess enough knowledge of both law and the subject at hand (a circuit design, software code, a rocket engine fuel injector, an automotive braking

Sally, the Service Maid:
The Case of the Crystal Pickup

Sally, the Service Maid - The Case of the Crystal Pickup, November 1944 Radio Craft - RF Cafe"Sally, the Service Maid" was a relatively short-lived feature in Radio Craft magazine. It began in early 1944 to bring deserved attention to the women who were left to run their husband's or brother's or son's electronics service shops while they were overseas securing the blessings of liberty for mankind. The sagas involved our heroine, Sally, confidently and impressively attacking malfunctioning electronic equipment in the stead of her father Gus Mason, who had volunteered his services as an instructor of electronics for the military. Unlike in past episodes where she tackled complex radio circuits for dashing military emissaries bringing equipment to her shop, this

Reader's Digest Model 800-XR
AM/FM Radio + 8-Track Tape

Reader's Digest Model 800-XR AM/FM Radio + 8-Track Tape Player - RF CafeWhile photographing the General Electric 7-4305c clock radio that I posted last week, it occurred to me that I had never posted anything on my Reader's Digest 800-XR stereo system. It is another of my had-since-a-teenager electronic items that still works as well as the day I bought mine in fall of 1975. Self-respecting audiophiles would never admit to having ever owned such a low-end system, but at least at the time it was the best I could afford. The price escapes me, but it was somewhere in the $100 neighborhood. A turntable came with it, but that is long gone now. Since I much prefer listening to over-the-air broadcasts rather than on the Internet, both the AM and FM tuners get a daily workout. A whopping 10 watts per channel stressed the limits of what my parents would tolerate, and

RF Wizard™
Amplifier Design Software

RF Tool Company Introduces RF Wizard for Amplifier Design - RF CafeRF Wizard creator Gordon Hockey wrote to let me know about his new software for RF amplifier design. "RF Wizard has been created for RF designers, educators, and students to greatly simplify the normally complex tasks associated with RF and microwave amplifier design for specific gain and bandwidth. It also simplifies the design of matching interconnection networks between RF subsystems such as antennas, transmission lines, amplifiers, mixers, etc." Only $39.99!

Custom Search
More than 10,000 searchable pages indexed.

Your RF Cafe
Progenitor & Webmaster

Click here to read about RF CafeKirt Blattenberger... single-handedly redefining what an engineering website should be.

View the YouTube RF Cafe Intro Video Carpe Diem!
(Seize the Day!)

5th MOB: My USAF radar shop

Airplanes and Rockets: My personal hobby website

Equine Kingdom: My daughter Sally's horse riding website