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"I do not look upon any system of wireless telegraphy as a serious competitor with our cables." - Sir John Wolfe-Barry
Today in Science History

High Exposure Advertising Plan Now Includes a 728x90-px Banner

High Exposure Advertising Plan Now Includes a 728x90-px Banner - RF CafeIn an ongoing effort to provide the best return on investment to RF Cafe website sponsors (aka advertisers), I have decided to allocate the 728x90-pixel banner ad slot at the bottom of all web pages to companies who participate in the High Exposure plan. That is in addition to the other features that have always been included. The cost is still only $150 per month; i.e., no price increase. A full list of advertising options is available on the Sponsorship Rates page, but just the features which are part of the High Exposure plan are highlighted in the screen capture ...

Codan Radio Communications in the Arctic

Codan Radio Communications in the Arctic - RF Cafe"During Exercise Northern Warrior 2018, 35 Canadian Brigade Group (35 CBG) Communications Detachment did an impressive job of testing and solving problems. The detachment's two objectives were to provide high-quality communications to the Arctic Response Company Group (ACG) personnel and test new equipment in an arctic environment. 'The arid and austere environment of the Canadian Arctic requires effective communications. The work done by the G6 35 GBC team has undoubtedly demonstrated the relevance of the HF communications that are essential to operate effectively in this hostile climate ..."

** New E-Mail Address for RF Cafe **

New E-Mail Address for RF CafeEarthlink no longer provides Internet service in the Erie area, and they want to charge a monthly fee to retain the current e-mail address, which is not worth the expense. Accordingly, please note that effective immediately RF Cafe's primary e-mail address will be rfcafe@yahoo.com. The Earthlink e-mail will be kept for a month or two so as not to miss any useful message, but please begin using the Yahoo e-mail now. I apologize for any inconvenience.

Methods of Suppressing PIM in Multicarrier Systems

Methods of Suppressing PIM in Multicarrier Systems - RF CafeSteve Ellis, product manager at Pasternack, wrote an article titled, "Methods of Suppressing PIM in Multicarrier Systems," that appeared in the February 2018 issue of Microwaves & RF magazine. "Passive intermodulation distortion (PIM) - the nonlinear effects that are observed from the passive components (i.e. antennas, cables, connectors, power dividers, and mixers) of a system at high signal levels - is a phenomena of particular relevance in wireless infrastructures dedicated to the propagation of vast amounts of traffic. Cellular and ...

Existence of New Form of Electronic Matter Demonstrated

Existence of New Form of Electronic Matter Demonstrated - RF Cafe"Researchers have produced a 'human scale' demonstration of a new phase of matter called quadrupole topological insulators that was recently predicted using theoretical physics. These are the first experimental findings to validate this theory. The researchers report their findings in the journal Nature. The team's work with QTIs was born out of the decade-old understanding of the properties of a class of materials called topological insulators. 'TIs are electrical insulators on the inside and ..."

Arecibo Radio Observatory Saved from Closure

Arecibo Radio Observatory Saved from Closure - RF Cafe"The Arecibo Observatory in Puerto Rico has been saved following an agreement signed by a consortium led by the University of Central Florida (UCF) in Orlando. The announcement was made on 22 February by the National Science Foundation (NSF), which has been looking for an alternative sponsor for the iconic, 305 m-diameter radio telescope since 2006. The NSF currently spends around $8M a year to keep Arecibo operating. The final impetus for the NSF to find new funding sources came in September 2017 when the telescope was damaged by Hurricane Maria ..."

ViaSat-2 Satellite Comms Services Now Available for Military

ViaSat-2 Satellite Communications Services Now Available for Military - RF Cafe"Viasat has announced the availability of the ViaSat-2 satellite communications (SATCOM) service for government, defense and military applications. The service leverages the most advanced communications satellite, ViaSat-2, along with innovations in ground networking technologies, that will deliver significant performance advantages over any other commercial or U.S. Department of Defense (DoD) SATCOM system. In early March 2018, Viasat conducted a ViaSat-2 SATCOM system demonstration ..."

What Is the Role of Satellite Communications in 5G?

What Is the Role of Satellite Communications in 5G? - RF Cafe"Satellite communications have been in use for decades now, providing connectivity to remote areas, acting as backup in disaster relief situations, and being a major access mechanism for TV in certain parts of the world. Satellite use has been vital for government, military, and remote operations, while geostationary orbit (GEO) satellites are providing global coverage for voice, TV, and, in some cases, broadband Internet services. The telco industry is now working toward the standardization and commercialization of the next generation of cellular standards ..."

Electrochemistry Quiz

Electrochemistry Quiz, March 1966 Popular Electronics - RF CafeA lot of RF Cafe visitors might not be familiar with some of the electronic devices presented in this Electrochemistry Quiz by Popular Electronics' resident quizmaster, Robert Balin (a big list of his other quizzes is at the bottom of the page). I offer my assistance. A is a photocell, B is an early type of rectifier, C is a varistor, D is a cathode ray tube (CRT), E is an electrolytic capacitor, F is a heated cathode in a vacuum tube, G is a flashlight battery, H is an early receiver crystal detector, I is a magnetic audio recording tape, and J is phonograph cartridge. I scored ...

3-D Measurements Improve Understanding of Geomagnetic Storms

3-D Measurements Improve Understanding of Geomagnetic Storm Hazards - RF Cafe"Measurements of the three-dimensional structure of the earth, as opposed to the one-dimensional models typically used, can help scientists more accurately determine which areas of the United States are most vulnerable to blackouts during hazardous geomagnetic storms. Space weather events such as geomagnetic storms can disturb the earth's magnetic field, interfering with electric power grids, radio communication, GPS systems, satellite operations, oil and gas drilling and air travel. Scientists use models of the earth's structure and measurements of Earth's ..."

RF Cafe Engineering & Science Crossword Puzzle for March 18

RF Cafe Engineering & Science Crossword Puzzle March 18, 2018Each week, for the sake of all avid cruciverbalists amongst us, I create a new technology-themed crossword puzzle using only words from my custom-created lexicon related to engineering, science, mathematics, chemistry, physics, astronomy, etc. You will never find among the words names of politicians, mountain ranges, exotic foods or plants, movie stars, or anything of the sort. You might, however, see someone or something in the exclusion list who or that is directly related to this puzzle's theme, such as Hedy Lamar or the Bikini Atoll, respectively. Enjoy! ...

Comics with an Electronics Theme, March 1967 Popular Electronics

Comics with an Electronics Theme, March 1967 Popular Electronics - RF CafeHere are a couple more electronics-themed comics from the March 1967 issue of Popular Electronics magazine for your TGIF enjoyment. The comic on page 100 especially appeals to me since I am finishing the installation of a Channel Master CM-5020 antenna. It has been a long time since I installed a traditional style TV antenna - about 40 years ago when I put a Radio Shack antenna on the roof of my mother's house. The entire 109" long by 100" wide antenna, including mounting hardware, weighs only 11.5 pounds and presents a wind resistance of 30 pounds. This is Channel Master's best antenna ...

8th RF & Microwave Paris Exposé

8th RF & Microwave Paris Exposé - RF Cafe
The 8th RF & Microwave Paris Exposé will be held March 21 & 22, 2018, at Porte de Versailles, Paris, France. Vendors will have products on exhibit, and conferences include EMC and RF simulation, IoT and Radio, Reliability of Components and Electronic Systems, GaN for Microwave Applications , Antennas Made by 3D Printing, GaN for Microwave Applications, Evolution ...

BAE Systems to Upgrade Australia's Long-Range Radar Network

BAE Systems Australia to Upgrade Australia's Long-Range Radar Network - RF Cafe"BAE Systems Australia today welcomed the announcement by the Minister for Defence, Senator the Hon Marise Payne and the Minister for Defence Industry, the Hon Christopher Pyne that the Company has been selected to upgrade Australia's long-range high frequency radar network. The Jindalee Operational Radar Network (JORN) protects Australia's coastal approaches through a network of three remote radars in Queensland, Western Australia and the Northern Territory. The radars play a vital role in supporting the Australian Defence Force's air and maritime ..."

Tech Industry Headlines

Tech Industry Headlines - RF Cafe- Archive -

Smart Antenna Market to be Worth $8.95B by 2025

Time for a Reality Check to 5G Exuberance

Trump Pushes for New "Space Force"

Tower Mounted Amplifier Market to See Decade of Growth

Researchers Claim AMD CPUs at Risk from 13 Critical Flaws

Color the Bands Green for Saint Patrick's Day

Trump Blocks Broadcom's Takeover of Qualcomm

UK Government Congratulates Itself on Contributing £25M to the 5G Cause

Business Is Booming at Boston Lawnmower - Thanks to Radio

Mac's Service Shop: Keeping Abreast of Your Field

Mac's Service Shop: Keeping Abreast of Your Field, April 1969 Electronics World - RF CafeMac and Barney discuss with some degree of trepidation the alarmingly increasing rate at which new electronics technology is being developed and marketed. As service shop owner and technician, respectively, they needed to constantly educate themselves on new components and circuits in order to stay current and be efficient enough to turn a profit. Mac recounts his lengthy background beginning with the days of mainly battery-powered AM radios, and progressing through AC-DC, FM and all-band (shortwave) radio, B&W television and the color TV, CB radios, and a new breed of appliances with electronic controls ...

FCC Accuses Startup of Launching Rogue "SpaceBee" Satellites

FCC Accuses Startup of Launching Rogue SpaceBee Satellites - RF Cafe"The U.S. communications agency says tiny Internet of Things satellites from Swarm Technologies could endanger other spacecraft. On 12 January, a Polar Satellite Launch Vehicle (PSLV) rocket blasted off from India's eastern coast. While its primary cargo was a large Indian mapping satellite, dozens of secondary CubeSats from other countries traveled along with it. Seattle-based Planetary Resources supplied a spacecraft that will test prospecting tools for future asteroid miners ..."

IPP-7148: New 90° SMD Coupler for 690-6000 MHz

IPP-7148: New 90° SMD Coupler for 690-6000 MHz - RF CafeInnovative Power Products introduces their latest 90° SMD Coupler that operates over the full 690 – 6000 MHz. band. Our new Model IPP-7148, handles 130 watts CW and comes in a small SMD Style package which is only 0.50 x 1.00 x 0.167 inches. The IPP-7148 will combine two signals up to 130 Watts CW of total output power. This coupler has very good amplitude balance across the whole band and insertion loss of <0.80 dB. The VSWR is less than 1.35:1 with greater than 16.5 dB of Isolation making them ideal for commercial, industrial or military ...

Chinese Lunar-Orbit Amateur Radio Payload Could Launch This Spring

Chinese Lunar-Orbit Amateur Radio Payload Could Launch This Spring - RF Cafe"China's twin-launch Chang'e 4 mission to the far side of the moon will place a pair of microsatellites in lunar orbit this spring 'to test low-frequency radio astronomy and space-based interferometry.' The two satellites, unofficially called DSLWP-A1 and DSLWP-A2 (DSLWP = Discovering the Sky at Longest Wavelengths Pathfinder), could launch this spring. The pair represent the first phase of the Chang'e 4 mission, which involves placing a relay satellite in a halo orbit to facilitate communication with the Chang'e 4 lander and rover ..."

Large Single-Crystal Graphene Could Advance Scalable 2-D Materials

Growing Large Single-Crystal Graphene Could Advance Scalable 2-D Materials - RF Cafe"A new method to produce large, monolayer single-crystal-like graphene films more than a foot long relies on harnessing a 'survival of the fittest' competition among crystals. The novel technique, developed by a team led by the Department of Energy's Oak Ridge National Laboratory, may open new opportunities for growing the high-quality two-dimensional materials necessary for long-awaited practical applications. Making thin layers of graphene and other 2D materials on a scale required for research ..."

Light-Sensitive Photodiodes

Light-Sensitive Photodiodes, July 1969 Electronics World - RF CafePhotodiodes and phototransistors were relatively new on the electronics scene in 1969 when this article appeared in Electronics World magazine. Prior to semiconductor light detectors, vacuum phototubes did the job in cameras, motion sensors, light level detectors, medical imaging equipment, etc. High voltages and the large volume for containing components supporting vacuum tubes created hazards (especially with medical equipment), inconvenience, and high cost. What we take for granted nowadays in terms of price, performance ...

Author: Kirt Blattenberger on Google+ Author:
Kirt Blattenberger