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"I was walking home one night and a guy hammering on a roof called me a paranoid little weirdo. In Morse code." - Emo Philips

Today in History

Mysterious Short Waves

Mysterious Short Waves, March 1935 Short Wave Craft - RF CafeIn 1935, not much was yet known about the ionosphere. Its existence was first theorized in 1902 by Arthur Kennelly and Oliver Heaviside, and Edward Appleton proved its presence in 1924 by conducting a series of broadcast experiments, but no direct measurements were possible until rocket-borne instruments could be launched. An Aerobee-Hi sounding rocket was launched in 1956 as part of the International Geophysical Year (IGY) project that made the first actual detection of ionized particles in what is now referred to as the D-layer. It is therefore forgivable that Hugo Gernsback, normally spot-on in his theories and postulations regarding RF propagation, incorrectly suggested in this editorial that based on observed

FCC Bureaucratic Strong-Arming

More FCC Bureaucratic Strong-Arming - RF CafeJust about a year ago I posted a report on the FCC punishing an amateur radio operator (Ham) for having an on-air conversation with another party who failed to identify himself per Part 97 requirements. Per FCC regulations, every control operator in the Amateur Radio Service (with few exceptions) is required to broadcast a station identification (call sign) at least once every ten minutes during periods of communication. The named operator properly identified himself, but was prosecuted for failing to terminate an exchange with someone else who did not comply. This legal action was executed by the same government which belittles honest citizens who object to its policies of ignoring illegal aliens crossing our

More Cardboard Slide Rule Calculators

Miteq: Mixer Spur Analyzer Calculator - RF CafeHP: Reflectometer & Mismatch Error Limits Calculator - RF CafeThanks to Joe Cahak, there are now 11 new cardboard calculators & slide rules added to the RF Cafe museum. Rare is the RF engineer or technician who has been in the business more than 20 years that has not used HP's classic Reflectometer & Mismatch Calculator slide rule. Most 'Millennials' might not even associate Hewlett Packard with test equipment unless they happen to work somewhere with a stock of vintage gear. They have phone apps for this type of work. A Miteq rotary Mixer Spur Analyzer is included, as are 9 others, some with which you probably are not familiar. Old-Guy Admission: I once carried these calculators in my shirt pocket right behind my plastic pocket protector

Bell Telephone Advertisement

Bell Telephone Ad, June 1946 Radio News - RF CafeRemember when you could hold a telephone conversation without having to allow a moment of time at the end of a sentence before responding in order to keep from 'stepping on' the person on the other end? It used to be only overseas phone calls or maybe communicating to astronauts on the moon suffered such inconveniences, but talking to someone across town was like having a face-to-face discussion. More often than not - or so at least it seems - there is a noticeable delay between the time someone actually stops talking on the transmitter end and the time the audio stops at the receiver end. People who have

Electronic Applications of the Smith Chart

Electronic Applications of the Smith Chart - RF CafeOne of the few aspects of electronics that has not changed since the early days of the craft is impedance matching and, in particular, use of the Smith Chart. Many an engineer, technician, and hobbyist has been intimidated by the chart's appearance; however, after using the Smith Chart a few times for impedance and/or admittance matching, quickly develops the knack of applying it. If you have an affinity for mathematics and are comfortable with complex numbers, all the arcs and circles makes perfect sense once the simple equations governing its construction are presented. As with so many other things, you wonder how anyone ever thought to do such a thing, and at the same time wonder why it took so long for someone to think of it. Gary Steinhour (KF6U), who recently

Electronics-Themed Comics

Electronics-Themed Comics, October 1963 Electronics World - RF CafeIt's always hard getting back into the swing of the workaday routine after a long holiday weekend. Now that you've finished trading stories with workmates about what you did - or did not - do, take one last moment to lift your spirits by looking at these electronics-themed comics from vintage issues of Electronics World magazine. I particularly like the step switches. BTW, these comics make good fodder for opening your technical presentations

Notable Tech Quote

James Michener Interview Photo ( photo) - RF Cafe"A scientist studies what is, an engineer studies what never was." - James A. Michener, historical fiction author.


Is Amateur Radio Still a Gateway to EE?

Is Amateur Radio Still a Gateway to Electrical Engineering? (Dan Romanchik) - RF CafeMany thanks to author and amateur radio operator Dan Romanchik (KB6NU) who sent this article for posting here on RF Cafe. A lot of electrical engineers and hobbyists are familiar with Mr. Romanchik from his stint as Senior Technical Editor for Test&Measurement World magazine (now part of EDN), and by his popular books on preparing for taking and passing Amateur Radio exams- including the newly released "No-Nonsense General Class License Study Guide." Contained within are Dan's observations regarding how Amateur Radio seems to be making a comeback in many realms including colleges, the popularity of radio displays in museums, and a rising number of 'hackers/makers' who are exploring the

U.S.A. Calling

U.S.A. Calling, January 1942 QST - RF CafeToday is Memorial Day in America. When America was drawn into World War II after the attack on Pearl Harbor on December 7, 1941, the country snapped into action and our citizens were ready, willing, and able to help. One big immediate need was knowledgeable electronics technicians and engineers, particularly people with experience in radio communications. Amateur radio operators were the natural reserve source for just that need. The FCC shut down Ham radio transmissions in January 1942 ostensibly for security reasons, but some suspect the reason was at least partly to motivate Hams to enter the armed services or work at government research laboratories. Still feeling

Tech Headline News

Airman's 'Frankenphone' Connects Ground Forces, Drone Pilots

AMS Chips Allow Cars to Be Unlocked and Started with NFC Phones

Physicists Solve Quantum Tunneling Mystery

New Maze-Like Beamsplitter Is World's Smallest

Samsung Patent Details Dual-OS Phone-Docking Hybrid Device

When Will ZigBee RF4CE Land in Europe?

Queen's Speech: New Monitoring Powers 'to Tackle Terrorism' (...and whatever else)

SpaceX Cleared for US Military Launches

Experiment Confirms Quantum Theory Weirdness

Murky Road Ahead for Android, Despite Market Dominance

Phones' Accelerometers Allow You to Be Tracked on the Metro

X-Ray Sensor Startup Raises Funds

RF Cable Assembly Designer by Pasternack

RF Cable Assembly Designer Unveiled by Pasternack - RF CafePasternack Enterprises has just released their newest engineering resource called the Cable Assembly Designer which allows the user to design and customize RF cable assemblies with an easy-to-use online web application at Pasternack’s new custom cable designer enables engineers and buyers to create customized RF cable assemblies that meet their specifications from any combination of compatible connectors and cables offered by the company. Over 250,000 possible combinations

Sound Broadcasting from Airplanes

Sound Broadcasting from Airplanes, September 1947 Radio News - RF CafeUntil maybe 20 to 30 years ago, there was still a certain amount of awe associated with new applications of technology. It seems anymore people are so accustomed to new and amazing things - usually at affordable prices - that the wonder is gone. Advancements are expected. The world is moving so fast that it is difficult to absorb and fully appreciate all the work being done. In 1947, both airplanes and electronics were still relatively new to a lot of people, especially in more rural areas, so a whiz-bang scheme like broadcasting messages from an airplane was

MECA Announces RF Parts On Demand (RFPOD)

MECA Announces RF Parts On Demand (RFPOD)MECA Electronics announces our expedited online service center, the source for RF Parts on Demand (RFPOD) when you need them. RFPOD offers an expedited online service that process your order and has it available for pick up at will call or shipment within 2 hours from order placement to pick up time! Will Call pick up hours are 9:00 AM to 5 PM (ET) - earlier hours are available by calling customer service in advance at (973) 625-0661. Let us help solve your component problem, we are here when you need us, orders are accepted 24 hours a day, 7 days a week and shipments are made same or next business day

Money in Radio Gadgets

Money in Radio Gadgets, February 1933 Radio-Craft - RF CafeSubstitute "cellphone" for "radio" in this title and editorial by Hugo Gernsback in 1933 and it would fit right in with today's market of wondrous gadgetry. Prescient as always, Mr. Gernsback describes, among other things, what we now refer to as energy harnessing to power ancillary devices and props. He also recommends a scheme for causing 'dancing dolls' on the surface of a table vibrated and mobilized by the sonic waves of a large speaker - a lot like the way years later vibrating football games were made (remember them?) where the men danced randomly

Nokomis Needs Engineers & Scientists

Nokomis Is Seeking Outstanding PhD and MS Level Electrical Engineers, Physicists and Computer Scientists - RF CafeThis is a good week for engineer job openings. Nokomis is seeking outstanding PhD and MS level electrical engineers, physicists and computer scientists position will support design and enhancement of next-generation RF/microwave devices. 3-10 years' experience is required depending on the position. Military background is a plus. Experience should include RF/microwave design and/or measurement with a focus on RF sensor systems and signal analysis. Experience with receivers, transmitters, and transceivers is a plus. Test and measurement experience as well as filter design

Acoustics Anagram

Acoustics Anagram, October 1961 Electronics World - RF CafeIsn't an anagram a word game where letters of one word are rearranged to spell another word or series of words? For instance, an anagram for 'microwave' is 'warm voice,' one for ''resistance" is "ancestries," and for "vector" is "covert." If so, then this puzzle is misnamed; it is really a crossword puzzle. Maybe back in 1961 the word anagram included this type of puzzle. Regardless of the naming error, I did learn a new word: "inertance," which means "the effect of inertia in an acoustic system, an impeding of the transmission of sound through

R&S Phase Noise Analyzer and VCO Tester

Rohde & Schwarz Presents the Ultrasensitive R&S FSWP Phase Noise Analyzer and VCO Tester - RF CafeThe new phase noise analyzer and VCO tester from Rohde & Schwarz enables ultrasensitive and ultra-fast phase noise measurements. The R&S FSWP also allows users to very easily measure pulsed sources and residual phase noise of RF components. Plus the instrument can be upgraded to a signal and spectrum analyzer. With the new R&S FSWP phase noise tester, users can measure the spectral purity of signal sources such as generators, synthesizers and VCOs more quickly than with any

Author: Kirt Blattenberger on Google+ Author:
Kirt Blattenberger