Category Archives: Ham Radio

Radio Waves: DIY Internet Radio With Real Buttons, Armed Forces Day Cross-Band Test, Tokyo Rose, Shortwave Collective, and RAC Portable Operations Challenge

Radio Waves: Stories Making Waves in the World of Radio

Because I keep my ear to the waves, as well as receive many tips from others who do the same, I find myself privy to radio-related stories that might interest SWLing Post readers. To that end: Welcome to the SWLing Post’s Radio Waves, a collection of links to interesting stories making waves in the world of radio. Enjoy!

Many thanks to SWLing Post contributors Paul, Dennis Dura, and David Goren for the following tips:

Internet radio with real buttons using Stream Deck (Bjørn Erling Fløtten)

How I used a Stream Deck Mini from Elgato in order to give my mother-in-law a super easy Internet radio experience.

By Bjørn Erling Fløtten, Trondheim, Norway. April 2021.

Background

My mother-in-law is from Poland. When she stays in Norway in order to help us with babysitting she misses Polish radio. In principle this is easily accessible through the Internet now from all kind of devices.

BUT, my mother-in-law is not PC-literate, nor does she use a so called ‘smart’-phone. With my long experience in teaching people far younger than her simple mouse and keyboard techniques, I knew that operating Windows and finding Internet radio stations on her own would just be too cumbersome. I therefore had to create a super simple setup for her, and my hacker mind started to think.

(I did of course consider special purpose Internet radios. They should in theory be quite simple to operate, but they all have som kind of quirks that I did not like. And besides, constructing something of your own is of course always more satisfying.)

I want Real Buttons!

What I really wanted was big buttons with tactile feedback. I had earlier experienced with some Behringer products (sound mixing board) in order to demonstrate mathematical functions. The idea then was to use turning knobs and sliders in order to see how changing parameters changed the outcome of the function, especially graphs in 2D and 3D.

I thought this would be useful also for an Internet radio, but then I remembered having read about the Optimus Maximus keyboard (keyboard with programmable led icons on each key), and I thought such a product would be even better. This search led to Elgato and their Stream Deck Mini. This has 6 buttons, just enough for a radio. I might have preferred the bigger version with 15 buttons but their products are ridiculously expensive, so I had to be content with just 6 buttons.

In addition to the Stream Deck Mini my son donated his old school laptop with Windows 10 installed. It was a cheap ThinkPad L-series which, although 3 years old and somewhat battered from daily use to and from school, was quite capable of streaming some audio from the Internet. My son created a guest account in Windows 10 with auto login. He set ‘Fn lock’ as default, meaning that keys F1, F2 and F3 was volume off, down, up without having to press Fn. We also found a pair of speakers lying around in the house.

No programming necessary *

(* But understanding of HTML, URLs and Windows command line arguments is a requisite.)

Initially I thought I would make a Windows application for controlling which radio streams to play. But it turned out that Elgato’s accompanying software was quite capable by itself.

I assigned five of the six available buttons to launch the standard web browser (Google Chrome in this case) with a corresponding streaming URL (radio channel).

Continue reading the full article by clicking here.

Annual Armed Forces Day Cross-Band Test set for May 7 – 8 (Southgate ARC)

The US Department of Defense will host this year’s Armed Forces Day (AFD) Cross-Band Test, Friday and Saturday, May 7 – 8, in recognition of Armed Forces Day on May 15. The event is open to all radio amateurs.

For more than 50 years, military and amateur stations have taken part in this exercise, designed to include amateur radio and government radio operators alike.

The AFD Cross-Band Test is a unique opportunity to test two-way communications between military and amateur radio stations, as authorized under FCC Part 97 rules. These tests provide opportunities and challenges for radio operators to demonstrate individual technical skills in a tightly controlled exercise in which military stations will transmit on selected military frequencies and will announce the specific amateur radio frequencies being monitored.

The schedule of military/government stations taking part in the Armed Forces Day Cross-Band Test and information on the AFD message is available on the MARS website.

Complete the request form to obtain a QSL card. ARRL

“Tokyo Rose” – WW2 Traitor or Victim? (YouTube)

Shortwave Collective – FENCETENNA (YouTube)

RAC Canadian Portable Operations Challenge Award (Southgate ARC)

The RAC Challenge Award: An Overview
Radio Amateurs of Canada is pleased to present a new Canadian Portable Operations Challenge Award for RAC members.

The objective of the new “RAC Challenge Award” is to recognize and encourage portable operations by RAC members from locations throughout Canada.

The new program will begin on Canada Day, July 1, 2021 and we hope it will become an annual event for RAC members.

Note: the following information is tentative as the new Awards program is still being organized so please stay tuned to this webpage for future updates.

Portable Operations
Portable operations are those in which Amateurs take their equipment, antennas and power supply to a location away from their home station to operate. This includes mobile stations, backpackers, DXpeditions and participation in events such as those described below:

Parks On The Air (POTA), a worldwide program of park activations – https://parksontheair.com/
Quebec Parks On The Air (QcPOTA) April 1 to December 31
Field Day: June 26-27
There are several other programs that celebrate portable operations including Summits on the Air (SOTA), Islands on the Air (IOTA) and the International Lighthouses and Lightships Weekend.

Features of the “RAC Challenge”
The new “RAC Challenge” will recognize all portable operations in which RAC members participate and will have similar features as a contest. Amateur Radio contests in VHF, UHF and the Microwave bands all have categories for “Rovers” – who move from grid square to grid square and “Backpackers” – who seek out hilltops from which to operate with highly portable equipment and antennas.

For many satellite operators, making contact with as many grid squares as possible is a mark of success. Some of those operators go on satellite DXpeditions to activate rare grids or operate from the intersections of grids to offer multiple grids with a single contact. In addition to being fun, these activities provide an opportunity for Amateurs to experience what is required to set up and operate under challenging conditions – valuable experience for emergency preparedness.

For more on the RAC Challenge Award, please see:

https://www.rac.ca/rac-canadian-portable-operations-challenge-award/

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Guest Post: A visit to Museo Marconi in Villa Griffone, Pontecchio, Bologna

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Many thanks to SWLing Post contributor, Ferruccio Manfieri (IZ1096SWL), who shares this report and excellent photo tour from a visit to the Museo Marconi in Bologna, Italy in 2018.

Today is International Marconi Day, so this is a very welcome, and timely post:

A visit to Museo Marconi in Villa Griffone, Pontecchio, Bologna

by Ferruccio Manfieri (IZ1096SWL)

Bologna, in Northern Italy, is renowned to be the seat of the oldest University in Europe and in the world (the Alma Mater Studiorum) and its historic, artistic and culinary heritage. From a scientific perspective, Bologna is the birthplace of Guglielmo Marconi as well as the place of his first experiments in transmission.

The inventor, born in Bologna on April 25th, 1874, was the son of an Italian father (Giuseppe, a wealthy landowner) and an Irish mother (Annie Jameson, of Jameson’s Whiskey family). At the age of 20, Marconi began to conduct experiments in radio waves, building much of his own equipment in the attic of his home at the Villa Griffone in Pontecchio (in the Bolognese countryside).

Marconi received his final resting place in Villa Griffone Mausoleum, an enterred crypt hosting his porphyr sarcophagus. The building was donated to the Guglielmo Marconi Foundation in 1941 after the death of the inventor (on the 20th of July 1937).

Sadly, Villa Griffone and the Mausoleum suffered heavy damages from WWII bombings and pillages and were patiently rebuilt in post-war years. Today, Villa Griffone is reborn as a hub of research and divulgation activities, hosting Guglielmo Marconi Foundation, the Marconi Museum, a library and two research groups on communication systems.

On the 26th of april 2019 I visited with my family the Museum hosted in the original building (a short trip from Bologna, 20 minutes by public transport)

Villa Griffone and the Marconi Mausoleum

The visit began with a nice stroll in the Villa gardens, home with the nearby hill of the Celestini of the first long-range and not in line of sight transmission experiment in 1895. Marconi managed to send signals over a distance of 2 km, beyond a hill situated between the transmission equipment (to which he had added a grounded vertical antenna) and the reception apparatus (characterised by an extremely sensitive coherer).

Villa Griffone gardens and “Hill of Celestini”

We were in the very spot Marconi was when he transmitted his three signals to the receiver operated by his brother and the gardener behind the hill. Nearby, the replica of eight meter wooden pole with the attached metal boxes used as antenna.

Marconi’s first “long range” antenna – replica

This experiment in universally aknowledged as the birth of radio transmission (and, by the way, the rifle shot used as a confirmation of the reception was the very first QSL…).

Our valent host and guide to the visit was the Director of the Museum, Barbara Valotti, who thoroughly described us (with knowledge, passion and communication skills) the historical framework of Marconi’s biography and works. A more engineering oriented and hands-on visit to the working replicas laboratory was subsequently hosted with passion and knowledge by Adriano Neri I4YCE.

In the Auditorium Dr. Valotti showed us two videos on the first transmission experiment and on the Republic incident in 1909, on of the first application of Marconi radiotelegraphy in an incident at sea, whose success (no lives were lost in the aftermath of the collision thanks to the coordination of rescue efforts via radiotelegraphy) gave a boost of popularity to radiotelegraphy and to the engineer, eventually leading to the Nobel prize in physics later that year.

A frame of the “Republic” video

This part of the visit emphasized his interest in real technological applications of his inventions and their commercial potential. Marconi was a “modern” mix of engineer (with an unhortodox, non-academic formation) and entrepreneur, ready to see the new potential applications of technologies in the society. Interestingly, Dr. Valotti underlined that the main focus of Marconi research was always the point-to-point trasmission and not the broadcast.

Hanging on the ceiling of the auditorium, a replica of the kite used by Marconi to lift an emergency antenna in the first transoceanic transmission from Poldhu to St Johns Newfoundland in 1901.

Yacht “Elettra” – memorabilias

The visit continued to the “silkworm room”, the original room (once used to breed silkworms) where Marconi held his laboratory and performed his experiments. The room was full of instruments replicas to show the laboratory as in the young Marconi years.

“Silkworm room” – Marconi’s first laboratory (original place, instrument replicas)

“Silkworm room” – Marconi’s desk (replica)

It was also possible to replicate the main experiments with educational working replicas.

Marconi transmitter – educational replica

Headphone and coherer used in the first transoceanic transmission (replicas)

The second phase of the visit was a more engineering-oriented explanation of the principles of radio telegraphy conducted by Adriano Neri I4YCE in a didactic laboratory on working replicas of the main epoch instruments.

Experiment table with working replicas: coherers, a wire decoder, a Marconi receiver

Instruments in the educational laboratory

With passion and competence, Mr. Neri explained us in a simple way (there were some very interested young people in the group) the cable telegraphy principles and the sequence of experiments and discoveries that led Marconi to his inventions.

In a detailed and fascinating exposition we saw applications of a Morse writer, the induction coil, the coherer and the first Marconi spark transmitter, all assembled in the end to transmit in the room some morse signals in the air.

Live demonstration of signal transmission by Adriano Neri . Against the wall a Marconi spark transmitter (note the antenna and ground plates), on the table: a Marconi receiver (with a coherer) connected with a Morse writer.

The laboratory, as the whole museum, hosts a huge number of working replicas (a wonderful collection in itself, handmade by Maurizio Bigazzi with rigorous standards of adherence to the original designs and, if possible, reuse of original parts) and some original equipment.

Ship wireless telegraph room – working replica

A last section of the museum is devoted to radio communication during the war (showing a WWI airplane-ground communication system) and radio broadcasting, with original sets of great interest like a 1923 Marconiphone (still working, we had a live demonstration receiving RAI programs) and a Ducati radio (the same Ducati company of motorbikes, based in Bologna).

WWI plane radio and ground receiver

1923 Marconiphone, working original set

Ducati radio

We spent all the morning in the Museum with great fun and interest from all the family.

I highly recommend a visit to the Museum for the place, its significance in the history of radio transmission and the competent and passionate exposition of the historical and technical themes related to Guglielmo Marconi.

A wealth of information (also in english) can be found of the Guglielmo Marconi Foundation website (www.fgm.it).

A detailed gallery of the Museum can also be found on the new Museum website (www.museomarconi.it)

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Radio Waves: Dirty Transmitters, World Amateur Radio Day, Electronic Echoes, DRM via Android, and 10 More BBC AM Services Close

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Radio Waves: Stories Making Waves in the World of Radio

Many thanks to SWLing Post contributors Grayhat, David Iurescia, Bill Hemphill, Harald Kuhl, and Troy Riedel for the following tips:

Transmitter Noise / Dirty Transmitters: Receiver Performance has hit a Brick Wall (DJ0IP)

For the past 15 years, Ham Radio’s Mega-Focus on Receiver Dynamic Range (DR3) has resulted in the community ignoring other factors that are just as important to receiver performance.

Even though our receivers have made a quantum leap in performance in important parameters such as DR3, RMDR, etc., On-The-Air Reception has gotten worse.

Unless used at a multi-transmitter site, today’s typical user won’t detect a difference in the receiver performance between a radio with 90 dB DR3 and a radio with 110 dB DR3. That’s because Receiver Performance is not the limiting factor.[…]

World Amateur Radio Day 18 April 2021 (IARU REGION 2 Newsletter)

World Amateur Radio Day (WARD) is an opportunity to celebrate the many accomplishments and contributions of amateur radio to the communications technology revolution which has dramatically impacted the daily life of virtually everyone on the planet. Many of these technologies and techniques started as experiments, not by governments or commercial enterprises, but by radio amateurs.

WARD 2021 commemorates the 96th anniversary of the International Amateur Radio Union’s founding in 1925, where amateurs first met in Paris to band together to give voice to these early experimenters to national governments and international bodies representing all radio amateurs.

The almost universal adoption of mobile technology created ever increasing demand on a finite resource, the radio spectrum. Access to useable spectrum is the fundamental base on which amateur radio was built and continues to be developed. As a result, amateur radio is very different than decades ago. Embracing new technologies and techniques has greatly expanded what amateur radio is and opened further possibilities as to what it could be. The proliferation of technology also means that the ongoing experimentation and innovation in electronics, radio frequency technique and radio wave propagation is no longer only the traditional realm of the radio amateur but also includes university research satellites, the “maker” community, and other non-commercial experimenters: citizen scientists.

Looking ahead, this ongoing evolution of the telecommunications ecosystem makes it clear that the national Member Societies of the IARU and IARU itself must also continuously change and adapt. A century later, the future possibilities are as exciting as ever.

Celebrate World Amateur Radio Day. The pandemic and more localized natural disasters continue to demonstrate the value of ordinary citizens as technically skilled contributors to society. The original social network is robust. Expose someone new to amateur radio (properly distanced), get on the air and contact the many special event stations, on HF, VHF, or satellite.

Electronic Echoes (KPC Radio)

From SWLing Post contributor Bill Hemphill:

“I have run across an interesting set of audio interviews that were done by Aaron Castillo of kpcradio.com. This is an internet based radio station of Pierce College in California.

Aaron did a series of audio interviews in the fall of 2020 called Electronic Echoes. See following link:

https://kpcradio.com/author/aaron-castillo/

STARWAVES DRM SoftRadio App upgrades mobile devices to receive undistorted DRM Digital Radio anytime and anywhere (Fraunhofer Press Release)

Horgen/Switzerland, Erlangen/Germany: Starwaves, a developer and distributor of receiver technologies centered around the digital broadcast standard DRM (Digital Radio Mondiale), joined forces with Fraunhofer IIS, a leading supplier in the field of broadcast encoder and receiver components for DRM, to develop an Android app that allows DRM reception on mobile devices. Starwaves enables Android phones and tablets to receive entertainment, text information, and emergency warnings via DRM Digital Radio – without costly data plans, independent from cell phone network availability, and based on innovative Fraunhofer technology.

Digital Radio Mondiale (DRM) is the digital successor standard to the classic AM and FM radio services. In many parts of the world, terrestrial digital radio broadcasts are already an important and trusted source of entertainment and information. They do not require monthly payments and work reliably even if there are no cell networks available. Radio reception with mobile phones and tablets combines the mobility and flexibility of these devices with the benefits of free-to-air radio services.

Starwaves has been active in the field of DRM radio receivers for many years. The “STARWAVES DRM SoftRadio” app was developed in close cooperation with Fraunhofer IIS. Its goal is to ensure easy access to innovative DRM radio services for everybody. It is available from now in the Google and Amazon Android app stores. The app provides listeners with access to all the essential features of the DRM digital radio standard, across all transmission bands from DRM on long wave to FM band and VHF band-III.

Fraunhofer IIS is a significant co-developer of core digital radio technologies. This includes the innovative xHE-AAC audio codec, which provides high audio quality at lowest data rates, as well as the Journaline application, which gives radio listeners access to news, the latest sports updates, local weather forecasts, travel tips, and even radio schooling services without requiring internet access.

The app also supports many more DRM features such as the Emergency Warning Functionality (EWF), image slideshows, station logos, and service descriptions including Unicode support for worldwide application. To provide all these services, the app only requires a standard off-the-shelf SDR RF dongle that is attached to the device’s USB port.

“We are proud to launch the world’s first low-cost full-featured DRM digital radio reception solution for mobile devices, developed in close partnership with Fraunhofer IIS. Now everybody can easily upgrade their existing mobile phone and tablet to enjoy DRM digital radio with its undistorted audio quality and advanced features including Journaline,” says Johannes von Weyssenhoff, founder of Starwaves.

I order to meet the needs of everyday radio listeners and to clearly separate this app from the engineering-driven approaches of the past, usability was a primary development objective from day one. With only a few clicks on the clutter-free interface, users select their preferred radio service, navigate through the clearly structured menus, and gain instant access to the various advanced information services that DRM provides. By supporting multiple user interface languages, the app ensures optimized usability in many countries around the globe.

About STARWAVES

Found in 2005 in Bad Münder, Lower Saxony/Germany, Starwaves had set its focus on the development and distribution of receiver technologies around the digital broadcast standard DRM (Digital Radio Mondiale). As far back as 2003 after both organizations, the DRM Consortium and the WorldDAB Forum, had expressed their appeal to the industry at IFA in Berlin to develop and produce multi-standard receivers compatible with both their systems, Starwaves developed its model ”STARWAVES Prelude”, the world’s first DRM-DAB receiver and presented it at CeBIT 2004 in Hanover. In 2006 Starwaves was again in the headlines with the ”Carbox”: It was the world’s first automotive DRM-DAB receiver which then was produced in volumes and enjoyed by lots of listeners worldwide – including many DXers thanks to its excellent analogue Short-Wave capabilities as well.

Since 2008 Starwaves moved its focus to Africa where it developed and tested an innovative approach of broadcasting community television in the L-Band with DVB-T2 in cooperation with ICASA – another world premiere. After DRM was chosen the national standard in India in 2012 Starwaves relocated its headquarters to Switzerland and started developing a new generation of DRM receivers.

Starwaves also initiated Africa’s first DRM trial in the FM Band in Johannesburg/South Africa and completed it with local and international partners. The trial report contains valuable discoveries regarding the feasibility of DRM for community radio which guided the South African government to adopt DRM in the FM Band for community radio and secured the report becoming an internationally recognized piece of standard literature, recently endorsed by ITU. Today, Starwaves offers various DRM receivers and broadcast solutions for consumers and the professional broadcasting industry.

For more information, contact [email protected] or visit www.starwaves.com/de/starwaves-drm-softradio

Ten more stations turn off Medium Wave services (Radio Today)

Ten more local BBC radio stations are turning off their Medium Wave transmitters for good this year.

BBC Essex, BBC Radio Cambridgeshire, BBC Radio Devon, BBC Radio Leeds, BBC Radio Sheffield, BBC Hereford & Worcester, BBC Radio Stoke, BBC Radio Lancashire, BBC Radio Ulster and BBC Radio Foyle will be FM and digital only in May and June 2021.

In addition, BBC Radio Wales and BBC Radio Gloucestershire will reduce AM coverage.

The BBC’s intention to close MW transmitters was first announced ten years ago in 2011.[…]

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Radio Waves: SpaceX Encrypts Falcon 9 After Ham Downloads Data, Postcard From Titanic Op at Auction, History of Sound Art, and WNYC’s Early Recording

Radio Waves: Stories Making Waves in the World of Radio

Many thanks to SWLing Post contributors Ulis (K3LU), Chris Walter, and Ron James for the following tips:

SpaceX Encrypts Falcon 9 Telemetry After Amateur Radio Operators Download Data (Extreme Tech)

SpaceX doesn’t operate like a traditional aerospace company. For one, the CEO is usually hamming it up on Twitter during launches and providing details that would usually go in a press release. SpaceX also live streams almost all of its launches, even the prototypes that have an unfortunate tendency to blow up lately. It wasn’t even encrypting the Falcon 9 telemetry feed… until now. Unfortunately, some digging by amateur radio tinkerers seems to have convinced SpaceX to step up its security.

It all started a few weeks ago when several Redditors managed to lock onto the 2232.5 MHz telemetry downlink from a Falcon 9 upper stage. Right away, they were able to pull out a few interesting plaintext snippets from the unencrypted feed. With a little more work, the radio enthusiasts were able to capture some amazing images from the spacecraft’s cameras.

After that discovery was public, other SpaceX fans tried to grab some data from the Starship during its prototype tests. However, SpaceX had chosen to encrypt that data. Even with the right wireless equipment, the decoded signal was just noise. Now, it appears the same thing is happening with the Falcon 9. When attempting to pull data from the most recent Falcon 9 launch, the original signal snoopers discovered it had also been encrypted. A series of tweets from SpaceX engineers suggest the decoding of the telemetry signal was the reason for the change.[…]

Postcard from Titanic’s radio operator is being sold at auction (Stars And Stripes)

BOSTON — A postcard written by the Titanic’s senior radio operator just weeks before the ocean liner sank in the North Atlantic in 1912 has been put up for auction.

The card, with a glossy image of the ill-fated ship on the front, was written by Jack Phillips to his sister, Elsie Phillips, in March 1912 while awaiting the ship’s first sea trials, according to RR Auction in Boston.

“Very busy working late. Hope to leave on Monday & arrive Soton Wednesday afternoon. Hope you quite OK. Heard from Ethel yesterday,” he wrote. It’s signed “Love Jack.”

It is postmarked Belfast, where the Titanic was built, and has a canceled halfpenny stamp.

“Soton” is a contraction of Southampton, the English port city from where the Titanic departed on its maiden voyage. It sank in the early morning hours of April 15.

Phillips, who turned 25 on board, stayed at his post after the Titanic struck an iceberg to send calls for assistance to other ships in the area until water was lapping around his feet, according to RR Auction.

He made it off the ship after being told by the captain that he had done his duty, according to his biography in the British National Archives, but died of exposure in the frigid North Atlantic, according to RR Auction.

The postcard is being sold by the estate of Vera and John Gillespie, longtime members of the Massachusetts-based Titanic Historical Society, said Bobby Livingston, executive vice president at RR Auction.[…]

Radio Survivor Podcast #292: The History of Sound Art (Radio Survivor)

What is sound art? And what do we know about its origin story? We explore this question and more with our guest this week, artist and educator Judy Dunaway. An adjunct professor in the History of Art Department at Massachusetts College of Art and Design, Dunaway’s recent article, “The Forgotten 1979 MoMA Sound Art Exhibition,” is a fascinating look at the history of sound art and highlights important contributions by female artists. In our wide-ranging discussion, we also hear about Dunaway’s own artistic practice, from her work with latex balloons to transmission art to a “phone improv” show over BlogTalkRadio a decade ago.

Click here to check out this piece at Radio Survivor.

Overcoming the Limitations of Time (From the January/February 1940 WNYC Masterwork Bulletin)

A MATTER OF RECORD: Mighty useful gadgets are WNYC’s four new recording machines. They were used in a variety of interesting ways during the past year, so we decided that the how and the why of recording would be an appropriate subject for this, the third of our Behind the Microphone series dealing with the technical side of things at the Municipal Station.

One of the most valuable uses of the recording units is that they have partially enabled us to overcome the limitations of time — have made it possible to make available to our listeners important evening programs which we could not broadcast directly because of our fluctuating time allotment.

For instance, we could not pick up the ASCAP Music Festival Concerts from Carnegie Hall last Fall because WNYC was not on the air after 8:30 P. M.[1] What to do? The recorders to the rescue! The concerts were “broadcast” over our regular Carnegie Hall lines to the Municipal Building where they were transcribed on our two standard studio-type recording machines. Each transcription[2] was put on the air on the afternoon following the original perfor

Similarly, our two mobile recording units made possible an afternoon broadcast of the official opening of La Guardia Field which took place at midnight. Recording equipment is also used frequently to transcribe major programs “off the air” so that they may reach a larger audience through rebroadcast. There was the time, for example, when the Mayor’s office was the scene of a final report on the new Police and Fireman’s pension plan. Official reports on the balloting were recorded and rebroadcast at a time when the majority of the policemen and firemen affected could listen in.

We used to think recording an easy job: Just put the recording needle on the disk, turn a few buttons, and let ‘er go. After watching one of our expert recording engineers at work, we realized that it’s a delicate task, requiring special training and long practice.

Click here to read the full piece at WNYC.

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Radio Waves: Extreme 2001 Geo Storm, Media Ownership Rules Loosened, Germany Bans RFI-Spewing Device, Blue Jays Radio, and L-Band Patch Antenna Review

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Radio Waves: Stories Making Waves in the World of Radio

Many thanks to SWLing Post contributors Troy Riedel, Dave Zantow, NT, Wilbur Forcier, and Rob for the following tips:

20 Years Ago, An Extreme Geomagnetic Storm (Spaceweather.com)

Unlike today’s blank sun, the solar disk 20 years ago was peppered with sunspots, including a monster named “AR9393.” The biggest sunspot of Solar Cycle 23, AR9393 was a truly impressive sight, visible to the naked eye at sunset and crackling with X-class solar flares.

On March 29, 2001, AR9393 hurled a pair of CMEs directly toward Earth. The first one struck during the early hours of March 31, 2001. The leading edge of the shock front was dense (~150 protons/cc) and strongly magnetized — traits that give rise to powerful geomagnetic disturbances. Within hours, an extreme geomagnetic storm was underway, registering the maximum value of G5 on NOAA storm scales.

“I was fortunate to witness and photograph the event when I was just a teenager,” recalls Lukasz Gornisiewicz, who watched the show from Medicine Hat, Alberta:

In the hours that followed, Northern Lights spread as far south as Mexico. In 20 year old notes, Dr. Tony Phillips of Spaceweather.com describes “red and green auroras dancing for hours” over the Sierra Nevada mountains of California at latitude +37 degrees. Similar displays were seen in Houston, Texas; Denver Colorado; and San Diego, California.

“Here in Payson, Arizona, red curtains and green streamers were pulsating all across the sky,” wrote Dawn Schur when she submitted this picture to Spaceweather.com 20 years ago:

“We have seen some auroras here before, but this display was really special,” she wrote.

A second CME struck at ~2200 UT on March 31th. Instead of firing up the storm, however, the impact quenched it. When the CME passed Earth the interplanetary magnetic field surrounding our planet suddenly turned north — an unfavorable direction for geomagnetic activity.

Indeed, the quenching action of the second CME may have saved power grids and other technological systems from damage. The storm’s intensity (-Dst=367 nT) stopped just short of the famous March 14, 1989, event that caused the Quebec Blackout (-Dst=565 nT) and it was only a fraction of the powerful Carrington Event of 1859 (-Dst=~900 nT).

The whole episode lasted barely 24 hours, brief but intense. Visit Spaceweather.com archives for March 30, 31st and April 1, 2001, to re-live the event. Our photo gallery from 20 years ago is a must-see; almost all the pictures were taken on film! [Read more at Spaceweather.com…]

U.S. Supreme Court permits FCC to loosen media ownership rules (Reuters.com)

WASHINGTON (Reuters) -The U.S. Supreme Court on Thursday allowed the Federal Communication Commission to loosen local media ownership restrictions, handing a victory to broadcasters in a ruling that could facilitate industry consolidation as consumers increasingly move online.

In a 9-0 ruling authored by Justice Brett Kavanaugh, the justices overturned a lower court decision that had blocked the FCC’s repeal of some media ownership regulations in 2017 for failing to consider the effects on ownership by racial minorities and women. Critics of the industry have said further consolidation could limit media choices for consumers.

The justices acted in appeals by the FCC, companies including News Corp, Fox Corp and Sinclair Broadcast Group Inc and the National Association of Broadcasters.

The associations for other broadcast networks’ local affiliates, including ABC, NBC and CBS, backed the appeals, arguing that consolidation would help ensure the economic survival of local television amid heavy competition from internet companies that provide video content. Broadcast television stations have said they are increasingly losing advertising dollars to digital platforms.[…]

Germany bans ‘water vitalizer’ over radio interference (AP News)

BERLIN (AP) — German authorities on Friday banned the sale and use of a New Age ‘water vitalizer’ device amid concerns that it is interfering with amateur radio signals.

The Federal Network Agency said it had received numerous reports that the device, sold by Swiss company Wassermatrix AG as a way to “activate” the body’s self-healing powers, was transmitting on the frequencies allocated for ham radio users.

The agency said owners of the 8,000-euro ($9,540) device, which has been sold more than 2,400 times in Germany, are allowed to keep but not use it.

Wassermatrix AG didn’t immediately respond to a request for comment.[…]

Rush’s Geddy Lee is unhappy about lack of Blue Jays radio for 2021 (Yahoo Sports Canada)

Canadian rock star Geddy Lee is less than thrilled with Sportsnet’s decision to cut their dedicated radio broadcast of the Toronto Blue Jays for the 2021 season.

Sportsnet won’t directly broadcast a separate radio feed and will instead simulcast their television broadcast over the airwaves for the 2021 season, becoming the first MLB team to do so. The decision was made to minimize travel and closely adhere to team, league, and government protocols related to the pandemic, Sportsnet said in a press release.

Lee, the lead singer for Rush, spoke about the importance of preserving a radio feed during an interview earlier in March.

Lee has been avid Blue Jays fan for years, throwing out the first pitch during the 2013 Blue Jays opener, and was a regular attendee at home games for decades.

It would be easy enough to spin this into “old man yells at cloud” in defence of a slightly outdated medium, but the sports media business is tough enough as it is, and the radio broadcast does indeed have charms that television simply can’t replicate, which is especially important for the visually impaired.[…]

L-Band Patch Antenna review (Frugal Radio via YouTube)

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Guest Post: Indoor Noise and Ferrites, Part1

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Many thanks to SWLing Post contributor, TomL, who shares the following guest post:

Indoor Noise and Ferrites, Part 1

by TomL

My magnet wire loop antenna on the porch reminded me to revisit aspects about my noisy Condo that I still needed to understand. Some RF noise I could control if I could find the right kind of information that is understandable to a non-engineer like me. There is a lot written about the general problem of noise and radio listening, for instance this ARRL article with web links to research – www.arrl.org/radio-frequency-interference-rfi, but I needed to get more specific about my particular environment.

I had tried some common clamp-on TDK ferrites I had obtained from eBay a long time ago but they only seemed to work a little bit. I have since found out these are probably the ones which are widely used on home stereo system connections used to reduce noise on those systems. There must be a better way.

The more I researched topics, like a portable “Loop on Ground” antenna, or, using RF chokes on the magnet wire loop, it dawned on my feeble, misguided brain that I was wrongly thinking about how to use ferrite material. For one thing, the material used to suppress RF noise is made with a certain “mix” of elements, like Manganese-Zinc, that electrically “resists” a specified frequency range. Fair-Rite has a useful Material Data Sheets web page which lists the Types of ferrite material. For dealing with noise (at the Source causing the problem), I needed to use the right kind of “Suppression” materials and proper placement. So, it (partly) made sense why the TDK snap-on ferrites might not fully work to reduce certain noise coming from my computer screens, LED lights, USB devices, and cheap Chinese-made power adapters.

A very good paper is by Jim Brown (K9YC) of Audio Systems Group entitled, “Understanding How Ferrites Can Prevent and Eliminate RF Interference to Audio Systems [PDF]”. There is a longer paper speaking directly to Amateur Radio folks, but the Audio version is simpler and it uses some of the same graphs and ideas. I was drawn to the very detailed Impedance measurements of many different “Types” of ferrite material used for different noise mitigation. I remember the traumatic pain of my college experience trying mightily to understand the Van Vlack Materials Science text book to no avail. But Jim’s paper reminded me of the importance of using the correct type of ferrite material and in an optimal way that reacts favorably in the target frequency range to solve a particular noise problem. So, what are my problem areas?

Shortwave Noise

Loop antennas have been what I have experimented with the most. They do not pick up as much man-made noise (QRM) and they have a space saving footprint. Fortunately, there is a wooden porch where these things have been tried. I had successfully built a broadband amplified “ferrite sleeve loop” (FSL) in the past. It was useful for a while but it fell into disrepair and also the Condo building has steadily increased in noise output. The amplifier was just amplifying the noise after a while. I also tried phasing two antennas but found the ever increasing noise cloud was coming from all directions and I could not null it out. I even tried a “mini-whip” from eBay but that just produced a wall of noise.

I recently tested AirSpy’s YouLoop written about before, and the results were good. However, it seemed obvious to me that it was too small as a passive loop to capture shortwave signals strongly enough without resorting to another amplifier attached at the antenna and would not improve the signal/noise ratio. My current solution is a unamplified stealth magnet wire loop about 32 feet in circumference. In that article, I mention things like common mode RF chokes at both ends of the antenna connection, horizontal polarization, and basically accepting that only the stronger shortwave signals will be received in a predictable manner. I think for now, this is about all I can do for shortwave and mediumwave noise, as far as my own Condo-generated noise. Neighborhood noise is a different topic.

VHF Noise

I then started to isolate which devices caused which kind of noise when listening to my outside amplified antennas for FM/VHF and UHF-TV transmissions. Many consumer Power adapters make a lot of noise from VLF up into UHF ranges. One thing I did right was to try a 10 pack of these little miracle “Wall Wart” toroids from Palomar Engineers. One by one, I put one of these small toroids (19mm inside diameter) on my home AC adapters as shown in the pictures, and the noises started disappearing. It does not explicitly say, but I believe it is Type 75 material which suppresses the noise generating AC adapter (at very low frequencies) when wrapped 8 – 12 times.

Most egregious of these was my CCrane FM2 transmitter. A strangled warbling sound kept emanating from the monitor closest to my laptop. Installing ferrites on the laptop and back of the monitor were not working. I moved the FM Transmitter and noticed a reduction in noise. So, I put one of these little toroids on the power input of the device and the noise disappeared. Apparently, it was picking up noise from the monitor (as well as its own power adapter) and rebroadcasting it to all my other radios! The strangled warbler is no more, I choked it (HaHa, sick bird joke).

While looking for the monitor noise, I put the eBay TDK ferrites on all the USB ports and HDMI ports. This has helped greatly on VHF and confirms my suspicion that these cheap TDK ferrites are indeed a common type of ferrite material. Some informative graphs can be seen in Jim Brown’s Audio paper mentioned before. One example might be Figure 22, which shows the #61 Series Resistance which peaks around 100 MHz when using a toroid with three “Turns”. More confused, I could not find a definition of a “Turn”. Eventually, in his longer paper to Amateur Radio operators, he defines it, “…is one more than the number of turns external to the cores”. Somewhere else he describes using many single snap-on ferrites being electrically equal to just one toroidal ferrite with multiple Turns. And interestingly, more Turns shifts the peak impedance substantially lower in frequency. So, using the graphs he supplies, one can target a noisy frequency range to try to suppress.

I then put 6 of the TDK ferrites on the VHF input to the AirSpy HF+. Some FM grunge was reduced and was thankful for that. The rest of the background noise truly seems to be coming from the outside picked up by the amplified antenna.

Also, I juggled a couple of the amplifiers around and now have separate VHF/FM and UHF/TV amplifiers which cleaned up the FM reception a little bit more – https://www.youtube.com/watch?v=zkDsy95et2w .

UHF TV Quality

On a whim, I put the balance of the TDK ferrites on the FM/TV splitter input cable, 10 in all. The FM reception did not improve but the Over The Air UHF TV reception Quality improved noticeably. My weakest TV station now has a stable Signal level and the Quality is pegged at 100%. This is a nice surprise since it means that now all local TV stations on UHF will come in cleanly without dropouts and I can view all digital subchannels. I was even able to rescan and added two more low-power stations never seen before. ?

LED lights

I have common LED lights hanging over a number of fish tanks and some grow lights over an indoor plant box and can hear this noise on upper shortwave and higher radio bands. In a future article, I will explore RF noise from lights as its own special topic. For instance, why do some LED lights generate RFI and how to know before buying (I am using BR30 spot bulbs from name brands)? Also, there is a new kind of LED “filament” light out now that uses much smaller LED’s on both sides of an aluminum strip, greatly reducing electromagnetic noise output (or do they??). More questions than answers.

I will explore creating my own customized AC power cord attached to the AC power strips of the LED lights. I will need to test this for safety and efficacy, so I will want to take some time to do this right. The hope is that, using Jim’s info, I will be able to create a broad spectrum RFI suppression AC power cord and cost less than $30 each cord. We’ll see.

Finally, I will look at “stacked” toroids using different mixes of ferrite Types, creating a custom RF suppression better than using just one Type of ferrite material, using AC cords as the main examples. For instance, the best set of graphs in Jim’s paper, in my opinion, are Figures 21 and 24 compared to each other. Something I did not know before is that one can not only use multiple turns on a single toroid to get a lower, peaked frequency response, but also stack multiple toroids of the same Type to get a smoother frequency response. Then on top of this, combine that set with other Types to create a customized frequency response curve.

Radios are quieter now. Those pesky grow lights are still a problem as well as the upstairs neighbor’s lights which seem to be on a timer, making FM reception noisy again after 5pm!

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HF-START Web Tool: A new web-based, real-time shortwave radio propagation application

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Many thanks to SWLing Post contributor, Tracy Wood, who shares the following journal abstract from EurekaAlert.com:

Commencement of shortwave propagation simulator (HF-START) service

Demonstrating radio wave propagation paths between any two points based on real-time space weather information

NATIONAL INSTITUTE OF INFORMATION AND COMMUNICATIONS TECHNOLOGY (NICT)

[Abstract]

The National Institute of Information and Communications Technology (NICT, President: TOKUDA Hideyuki, Ph.D.), in collaboration with Electronic Navigation Research Institute, National Institute of Maritime, Port and Aviation Technology (ENRI, Director General: FUKUDA Yutaka) and Chiba University (President: TOKUHISA Takeshi), has started the service of shortwave propagation simulator (HF-START). It provides real-time shortwave propagation that reflects real space weather information from ground-based observations and model calculations. The HF-START web system has been successfully developed and is now available at https://hfstart.nict.go.jp/.

The web calculation function of this system allows shortwave propagation between any two points in Japan based on real-time GNSS observations and between any two points on the Earth based on model-based space weather information. Real-time estimation is possible. The calculation in the past and up to about 1 day ahead in the future is also possible. In addition to amateur radio, HF-START is expected to benefit efficient frequency operation of aviation communications that relies on shortwave in the polar route.

[Background]

Communication and positioning technologies play an important role in social infrastructure in various fields today. The ionosphere has regular temporal cycles and fluctuates greatly every day associated with solar activity and space environment. Of benefit to us is the fact that ionosphere is good at refracting shortwave, which is why we can hop shortwave signals off the ionosphere to communicate with people over large distances.

Shortwave band has been used for communication and broadcasting for a long time, and are still widely used in radio broadcasting, aviation communication, amateur radio, etc. Ionospheric variation, however, has a great influence on the propagation of radio waves. Communication environment such as the communication range and usable frequency changes significantly due to the influence of the ionospheric fluctuation. Thus, fluctuations in the ionosphere affect the operation of shortwave broadcasting, aviation communications, and amateur radio.

There have been websites that provide estimated information on how radio wave propagation changes due to such ionospheric fluctuations. The problem is that it is based on a simple model and does not reflect realistic ionospheric fluctuations.

[Achievements]

We have developed a shortwave propagation simulator HF-START that estimates and provides shortwave propagation information in real-time under realistic ionospheric fluctuations based on ground-based observations and model calculations. We open real-time information estimated by HF-START, and the web application at https://hfstart.nict.go.jp/.

Figure 1 shows an example of visualization of shortwave propagation by HF-START. In this system, the user can check the radio wave propagation information that is updated in real-time. As shown in Figure 2, the user can also use the web application to estimate and visualize radio wave propagation by specifying any frequency in the range of 3-30 MHz, any two points on the Earth, and any transmission angle. The date and time can be set retroactively to the past (after 2016), to the real-time, and in the future (up to about 1 day ahead).

The system can be used to visualize the radio propagation path and clarify whether it is affected by space weather when the shortwave you are using does not reach the destination, or when you can listen shortwave broadcasted from the far source that normally you cannot hear. Furthermore, in addition to amateur radio, it is expected to benefit efficient frequency operation of the aircrafts that use shortwave in polar route.

[Future Prospects]

We are conducting research and development to extend the HF-START to estimate radio wave propagation not only in the shortwave band but also in other frequency bands. In addition, we will evaluate the simulator accuracy and improve it by comparing it with radio wave propagation observations.

NICT has been providing information related to communications, satellite positioning, and radiation exposure since November 2019 as a member of the Global Space Weather Center of the International Civil Aviation Organization (ICAO). With the HF-START service, we expect to improve the information provided to directly relate to communications, such as communication range information.

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As the abstract mentions, you can use the tool online now via the HF-Start Web Tool.

Thanks so much for the tip, Tracy. This is fascinating!

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