Custom Search

More than 10,000 searchable pages indexed.

Greetings: There is so much good stuff on RF Cafe that there is no way to list or link to all of it here. Please use the Search box or the Site Map to find what you want - there is a good chance I have it. Thanks!

•−•  ••−•    −•−•  •−  ••−•  •
RF Cafe Morse Code >Hear It<
Job Board
About RF Cafe™
Copyright 1999-2015

- RF Cafe Homepage -
"Any time the voltage 'over here' is different than the voltage 'over there,' current will flow." - H. Ward Silver

Today in History

Tech Headline News

- Archives -

Majority of Telecoms Firms Set to Create New Roles in 2015

Japan Bumps China as Top Holder of U.S. Treasury Debt

Nootropic Brain Drugs Rise in Popularity for Today’s Cutthroat Corporate Climbers

An Unexpected Source of Mobile Security: Ada (haven't seen Ada in news since Y2K scare)

Teen Charged For Using Teacher's Admin Password to Access School Computer

Moore’s Law Hits Middle Age

Indian Companies Withdraw from Facebook's

Vodafone Recovering from Network Outage

Double Walled Carbon Nanotubes Allow Gandgap Tuning

FCC to Pirates: We're Still Hunting You

EU accuses Google of Abusing Search Dominance, Opens Android Investigation

TSMC Cuts Capex by $1B

Local Broadcasters Could Reap Billions in Airwaves Auction

Defense Electronics Industry Concerned over Cyber Security

IEEE 2015 International Microwave Symposium (MTT-S) to Include Amateur Radio Presence

Nokia Buys Alcatel-Lucent for $16.5B

2015 Salaries for 10 Engineering Disciplines

Patents Forecast Technological Change (duh)

RF Cafe's RF Calculator
Workbook Updated to v7.1

RF Cafe Calculator Workbook v7.1 (download for free) - RF CafeWhile updating the Doppler frequency reference page, I discovered an error in the free RF Calculator Workbook v7.0. It does not properly adjust the units based on user settings. I just posted v7.1 to fix the issue. RF Calculator Workbook v7.1 can be downloaded now, also for free. If you purchased the unlocked version, please contact me and I will send you a replacement. Please forgive the inconvenience.

The "G-Line" Community
TV System

The "G-Line" Community TV System - RF CafeWhen I first saw this article on the 'G-line' transmission system, I thought the cone at each end of the line was just a gimmick to make it look high-tech. My ignorance of the way the system works was responsible. As it turns out, the 'G-line' transmission medium, named after inventor Dr. Georg Goubau, an engineer at the renowned U.S. Army Signal Corps Engineering Laboratories at Fort Monmouth, NJ, used the cone to transition a finite radius coaxial cable outer conductor to an infinite radius, sort of virtual, outer conductor that was free space. Doing so permitted a single line to do the job of carrying a signal from point A to point B. This significantly reduced the installation and maintenance cost of

Bell Telephone Laboratories
Ad: Transatlantic Cable

Bell Telephone Laboratories Ad: Transatlantic Cable, November 1956 Radio & Television News - RF CafePrior to satellite communications, long-distance messages were carried by footmen, horses and riders, smoke signals, trains, airplanes, boats, lanterns, sign language, printed media, radio frequency, and cables. All had their advantages and disadvantages, but none other than cable could provide reliable, nearly instantaneous conversations across and between continents - or cities for that matter. Stringing wires on poles over the landscape was a relatively simple task compared to that of laying cable along the ocean floor. Maintenance on underwater cable and amplifiers was exceedingly difficult or even impossible in some sections. Developing a suitable insulation to withstand the harsh salt water environment and the extreme pressures at great depths

Author: Kirt Blattenberger on Google+ Author:
Kirt Blattenberger

Crosley Radio Advertisement

Crosley Radio Adverisement, February 1932 Radio-Craft - RF CafeCommercially 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.

Skyworks Intros 8 Low Noise
Variable Gain Receive Modules

Skyworks Introduces Low Noise Variable Gain Receive Modules for LTE and WCDMA Infrastructure - RF CafeSkyworks 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

"-Tron" Teasers
An Electronic Quiz

"-Tron" Teasers - An Electronic Quiz, October 1963 Electronics World - RF CafeThyratrons, klystrons, and magnetrons I've heard of, but trochotrons, charactrons, tonotrons I ain't heard of. That made this quiz more of a learning exercise for me than a test of any sort of knowledge possessed. Heck, I thought an 'ignitron' was a pejorative term for a really dumb techie wannabe. In all there are 17 types of '-tron' devices given for which to match from a list of descriptions. You'll probably do better than I did

Thunderbolts and Whistlers

Thunderbolts and Whistlers, December 1956 Popular Electronics - RF CafeThe first electronic circuit I remember building as a budding teenage tinkerer was a 'whistler' detector, aka a 'sferic.' Instructions and a schematic came from a project book I bought at Radio Shack. A whistler is a time-varying electromagnetic signal that decays in both frequency and volume over a short time - like sounds made by the eponymous fireworks genre. Having always had an interest in weather phenomena as part of my flying hobbies,, it seemed like an apt learning endeavor. To my recollection, the whistler detector was a simple diode circuit with a couple Rs, Ls, and Cs strewn around in a particular configuration, and a long wire antenna. I can't honestly say

Radar Scores SAC
Bombing Test

Radar Scores SAC Bombing Test, December 1956 Popular Electronics - RF CafeMost 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

Hiram Percy Maxim Dies

Hiram P. Maxim Dies, May 1936 Radio-Craft - RF CafeHiram Percy Maxim is a name known to every American licensed amateur radio operator, since he was the primary found of the American Radio Relay League (ARRL). This obituary that was printed in the May 1936 edition of Radio-Craft reported on his death at age 66 (the article incorrectly says 67 years old) - young by today's standards, but about normal a century ago. Although he lived in Connecticut, he was buried in Rose Hill Cemetery, located in Hagerstown, Maryland. A couple years ago, Melanie and I were visiting her mother, who lives in Hagerstown (we once lived there as well), and set out to locate his place of final rest. I wrote about in this story titled "Hiram Percy Maxim's Gravesite in Hagerstown, Maryland."

Orbel Honored with Governor’s
ImPAct Award

Orbel Honored with Governor’s ImPAct Award - RF CafeOrbel Corporation is being honored with a Small Business ImPAct Award as part of the third annual Governor’s ImPAct Awards, recognizing businesses that create jobs and generate an economic impact within the state. The Small Business ImPAct Award is given to a small business (100 or less employees) that is an innovator within its industry, demonstrated revenue/profit growth, increased its workforce, and is committed to the growth and development of its employees and community. Orbel’s EMI/RFI shielding technology has helped to usher in automation to nearly all industries, promoted the viability of manufacturing within the

Notable Tech Quote

The Psychology of Productivity, Leigh Buchanan - RF Cafe"Because we now have shared calendars, people can kidnap our time." - Leigh Buchanan, The Psychology of Productivity, Inc magazine.

MECA Electronics Intros
Low PIM 10 Watt Terminations

MECA Electronics Intros Low PIM 10 Watt Terminations - RF CafeFeaturing 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
, while handling
    full rated power to +85°C.
* 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

Made in USA and 36-month warranty!

littleBits™ Modular System
Electronic Building Components

littleBits™ Modular System Electronic Building Components - RF CafeSteve 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

Path Loss, Propagation Time,
& Doppler Radar Pages Updated

Path Loss, Propagation Time, Doppler Radar - RF CafeThe latest RF Cafe reference pages to be updated are Doppler, Path Loss, Propagation Time, and Radar Equation. As with the others, graphics have been improved and page content reformatted to be (hopefully) more user friendly. Please let me know if you spot any problems. Thanks.

Oscilloscopes for Radio
Amateurs: Add to Ham Shack

Oscilloscopes for Radio Amateurs: Add a Scope to Your Ham Shack - RF CafeOscilloscopes for Radio Amateurs: Add a Scope to Your Ham Shack, by Paul Danzer, is filled with practical information you’ll need for using a scope. It begins with an overview of the oscilloscope and continues on to discuss characteristics, applications, probes, controls, and input modes. If you’re considering adding this piece of test equipment to your ham shack, there is an explanation of scope specifications and features to help you select an oscilloscope that is right for you.

Heuermann HF-Technik 2.45 GHz
Generators & Plasma Jets

Heuermann HF-Technik Intros 2.45 GHz Generators & Plasma Jets - RF CafeHHF is the first company who offers generators (PlasMaster) in the power range between 10 W and 200 W including a control circuit to fulfill hot S-parameter measurements and to look on the best S11-value in the IMS-band. Additionally plasma jets from 10W-MiniJet up to 200W-PCA jet with cannula for cleaning, disinfection, activating, coating, melting and welding, as well as a low power generators, low pressure chamber coupler, and more support equipment.

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