Tag Archives: Mediumwave

The AMT-MW207 mini AM radio transmitter kit

Many thanks to SWLing Post contributor, Frans Goddijn, who shares the following video demonstrating the AMT-MW207: a tiny $25 mediumwave transmitter kit that can be purchased on AliExpress:

To be clear, the AMT-MW207 is not designed to be a whole house AM transmitter like the SSTran and others.

The seller describes it as a device to debug and test AM receivers. Since it only employs a built-in bar antenna, the transmitter would need to be placed in close proximity to the receiver.

Click here to view on AliExpress.

Thanks for the tip, Frans!

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Fun with “The Radio Boys”

By Jock Elliott, KB2GOM

Back in April of this year (2022), I accidentally discovered The Radio Boys series of books, many of which are available for free if you have an Amazon Kindle.

These books, I believe, are intended for young adults, and, in my mind, they very much resemble The Hardy Boys series of books: a group of high school friends have adventures and discover the wonders of radio together. Think “The Hardy Boys go all-in for radio,” and you have the right idea.

If you are looking for sophisticated plots, deep character development, and a lyrical turn of phrase, you will be disappointed. But if you a looking for a light-hearted adventure with deep enthusiasm for radio, I think you will be pleased.

But what makes these books really cool is that they were written and copyrighted 100 years ago, in the early 1920s. Yes, some of the language and attitudes are somewhat antiquated, but what is fascinating is the window they offer on radio a century ago.

My knowledge of radio history is very limited, but it is my understanding that radio was just beginning to be popular in American culture in the early 1920s, The Radio Boys books reflect this. The first book, The Radio Boys’ First Wireless Or Winning the Ferberton Prize, gives fairly detailed instructions for making your own radio receiver with materials you could get (in the early 1920s) from the local hardware store.

At various points in the books, The Radio Boys extol the virtues of radio: people could hear concerts in the comfort of their own homes or listen to baseball games; if there were radios in cars, travelers could keep track of weather reports; it was a novelty when a minister broadcast the church service; college professors could broadcast their lectures, and so forth. I find the books offer a charming perspective on what we take for granted today.

And, if you have an Amazon Kindle, many of The Radio Boys books are available at no cost.

Click here to check out some of The Radio Boys titles on Amazon.com.

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Radio Waves: DRM Demo in Australia, Decoding the JWST, the ARDC, and EV Makers Dropping AM Radio

Radio Waves:  Stories Making Waves in the World of Radio

Welcome to the SWLing Post’s Radio Waves, a collection of links to interesting stories making waves in the world of radio. Enjoy!


Australia Demonstrates DRM on AM, FM (Radio World)

Since September 2020, ABC Radio has been quietly trialing DRM technology in Victoria

The public-service Australian Broadcasting Corp. and its transmission contractor BAI Communications Transmission Network hosted a public demonstration of Digital Radio Mondiale broadcasts on June 29, 2022. ABC highlighted the use of DRM on both AM and FM in Wagaratta, Victoria.

According to the DRM Consortium, the demonstration was the culmination of almost two years of COVID-impacted work to assess the performance of DRM services in Australia’s VHF and medium-wave bands.

Previously, the Australian Amateur Radio Experimenters Group reported that AREG member Steve Adler (VK5SFA) had been monitoring “a very un-publicized Digital Radio Mondiale (DRM) trial” on 747 kHz from Wangaratta in August 2021.

The Australian Communications and Media Authority provided ABC with a license variation to conduct the DRM 30 trials from September 1, 2020, to August 31, 2022.

At the public demonstration, senior representatives from the public, commercial and community radio sectors, along with regulators and other interested parties, were able to hear and see the capabilities of DRM broadcasting on AM from Dockers Plains and on FM from Mount Baranduda. They were also able to review the transmission equipment at Wagaratta.[Continue reading…]

Also check out the DRM Consortium’s article on this same topic.

Decoding James Webb Space Telescope (Daniel Estévez)

The James Webb Space Telescope probably needs no introduction, since it is perhaps the most important and well-known mission of the last years. It was launched on Christmas day from Kourou, French Guiana, into a direct transfer orbit to the Sun-Earth L2 Lagrange point. JWST uses S-band at 2270.5 MHz to transmit telemetry. The science data will be transmitted in K-band at 25.9 GHz, with a rate of up to 28 Mbps.

After launch, the first groundstation to pick the S-band signal from JWST was the 10 m antenna from the Italian Space Agency in Malindi, Kenya. This groundstation commanded the telemetry rate to increase from 1 kbps to 4 kbps. After this, the spacecraft’s footprint continued moving to the east, and it was tracked for a few hours by the DSN in Canberra. One of the things that Canberra did was to increase the telemetry rate to 40 kbps, which apparently is the maximum to be used in the mission.

As JWST moved away from Earth, its footprint started moving west. After Canberra, the spacecraft was tracked by Madrid. Edgar Kaiser DF2MZ, Iban Cardona EB3FRN and other amateur observers in Europe received the S-band telemetry signal. When Iban started receiving the signal, it was again using 4 kbps, but some time after, Madrid switched it to 40 kbps.

At 00:50 UTC on December 26, the spacecraft made its first correction burn, which lasted an impressive 65 minutes. Edgar caught this manoeuvre in the Doppler track.

Later on, between 7:30 and 11:30 UTC, I have been receiving the signal with one of the 6.1 metre dishes at Allen Telescope Array. The telemetry rate was 40 kbps and the spacecraft was presumably in lock with Goldstone, though it didn’t appear in DSN now. I will publish the recording in Zenodo as usual, but since the files are rather large I will probably reduce the sample rate, so publishing the files will take some time.

In the rest of this post I give a description of the telemetry of JWST and do a first look at the telemetry data. [Continue reading…]

Helping Secure Amateur Radio’s Digital Future (Hackaday)

The average person’s perception of a ham radio operator, assuming they even know what that means, is more than likely some graybeard huddled over the knobs of a war-surplus transmitter in the wee small hours of the morning. It’s a mental image that, admittedly, isn’t entirely off the mark in some cases. But it’s also a gross over-simplification, and a generalization that isn’t doing the hobby any favors when it comes to bringing in new blood.

In reality, a modern ham’s toolkit includes a wide array of technologies that are about as far away from your grandfather’s kit-built rig as could be — and there’s exciting new protocols and tools on the horizon. To ensure a bright future for amateur radio, these technologies need to be nurtured the word needs to be spread about what they can do. Along the way, we’ll also need to push back against stereotypes that can hinder younger operators from signing on.

On the forefront of these efforts is Amateur Radio Digital Communications (ARDC), a private foundation dedicated to supporting amateur radio and digital communication by providing grants to scholarships, educational programs, and promising open source technical projects. For this week’s Hack Chat, ARDC Executive Director Rosy Schechter (KJ7RYV) and Staff Lead John Hays (K7VE) dropped by to talk about the future of radio and digital communications. [Continue reading…]

Interference causes EV makers to drop AM radio (Radio World via the Southgate ARC)

Radio World reports the Electromagnetic Interference generated by Electric Vehicles is causing some EV automakers to drop AM (medium wave) radio

The article says:

Some EV automakers are dropping AM altogether due to audio quality concerns, but that’s just one piece of the puzzle as radio continues to fight for space on the dash.

“As carmakers increase electric vehicle offerings throughout their lineups, the availability of AM radio to consumers is declining,” said Pooja Nair, communications systems engineer with Xperi Corp., in a Radio World guest commentary. “This is because the effects of electromagnetic interference are more pronounced in EVs than in vehicles with internal-combustion engines.”

In other words, electromagnetic frequencies generated by EV motors occupy the same wavelength as AM radio signals. The competing signals clash, effectively cancelling each other out. As EV motors grow more powerful, AM static tends to increase.

Read the full story at
https://www.radioworld.com/news-and-business/headlines/why-are-some-automakers-ditching-am-radio


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FM World reports that RAI will end mediumwave broadcasts later this year

Many thanks to SWLing Post contributor, Pedro Andrade, who shares the following article. Note that the following excerpt has been translated by Google from Italian to English. Click here for the original in Italian at FM-World.it:

On 11 September 2022 Rai radio broadcasts in medium wave will cease (FM World)

Before the end of the summer, Rai will end radio broadcasts in medium wave .

[…]The news, already anticipated in recent months by sector magazines such as Italradio , is made known by the Easy Web section of Rai .

Everything comes from the audio description for the blind, available for some programs in the second audio track of the TV channel concerned, but also in medium wave on Rai Radio1 .

With regard to this latter service, the site (accessible by clicking HERE) specifies that “from 11 September 2022, due to the termination of Rai radio broadcasts in medium wave modulation, the audio descriptions of television programs for the blind will be available only on dedicated audio of digital terrestrial television.

The regular Rai radio programs , therefore, will continue in FM , DAB + , web and app .

Thanks for the tip, Pedro.

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Radio Waves: Future of AM in UK, BBC and Nuclear War, SAQ Unable to Air on Alexanderson Day 2022, ITU Ham Station Celebrates 60 years, and RRI International Quiz

Radio dial

Radio Waves:  Stories Making Waves in the World of Radio

Welcome to the SWLing Post’s Radio Waves, a collection of links to interesting stories making waves in the world of radio. Enjoy!


Opinion: The Future of AM Radio
England, Scotland, Wales and Northern Ireland (FrequencyFinder.co.uk)

Summary

AM radio in the British Isles is now in terminal decline with audiences dropping and many transmitters closed already. The majority of the remaining transmitters will likely close by the end of 2027. Over the next few years, the BBC and major commercial broadcasters will be looking to minimise their AM transmission costs by reducing transmission powers at the high-power sites and closing some of the low-power transmitters serving small audiences.

A coordinated AM shutdown may then follow at some point, most likely in 2027, though some independent broadcasters may continue using AM beyond this. This article explores these issues in more detail.

Click here to download the full PDF of this article.

The Last Word – The BBC and Nuclear War (Atomic Hobo Podcast)

This episode of the Atomic Hobo podcast focuses on the role of the BBC before and after nuclear attack:

Click here to listen via Soundcloud.

SAQ unable to air on Alexanderson Day (The Alexander Association)

Note: the The Alexander Association has announced that they will be unable to put SAQ on the air this year on Alexanderson Day. There are no more details other than the title of their post (the content still reads as if the transmission will happen as planned).

Check the Alexander Association website for more details.

ITU’s ham radio station celebrates 60 years on air (ITU)

By Nick Sinanis, callsign SV3SJ, President of the International Amateur Radio Club (IARC), and Attila Matas, callsign OM1AM, Vice-president and Station Manager, IARC

Did you know that the United Nations specialized agency for information and communication technologies owns and operates its very own radio station?

Residing at the headquarters of the International Telecommunications Union (ITU), the 60-year-old amateur station operates under the callsign 4U1ITU.

It started broadcasting on 10 June 1962 and was officially inaugurated the following month by then UN Secretary-General U Thant and ITU Secretary-General Gerald Gross – himself a ‘’ham” radio enthusiast known by the personal callsign W3GG.

Recognized as a unique “country” in the ham radio community, 4U1ITU operates in accordance with privileges extended by ITU and the Government of Switzerland. It has also earned the DXCC (or ham radio “century club”) award from the American Radio Relay League (ARRL), confirming air contacts with 100 or more countries.

From its long-time home on the 5th floor of the Varembé Building in Geneva’s international district, this unique broadcasting outlet still today serves as a model for the highest standards of amateur radio station operation everywhere.

From one to a million

4U1ITU’s first contact, or “QSO” in ham radio parlance, was made with a German station called DL4VK. Further QSOs followed, amounting to over 1,300 contacts worldwide in the first 24 hours.

In the six decades since, ITU’s radio station has made over a million contacts using Morse code carrier wave (CW), voice (SSB), and digital operational modes, based on more than 20,000 two-way QSOs with radio amateurs around the world.

4U1ITU can operate on most of the frequency bands allocated to amateur and amateur-satellite services as identified in Article 5 of the Radio Regulations.

Aside from letting licensed radio amateurs in ITU, its Member State representatives, and its conference and meeting delegates contact fellow radio hams, the station promotes international goodwill and cooperation across the community. It also allows hands-on demonstrations of amateur radio communications for delegates and meeting participants. [Continue reading…]

RRI Voice of Indonesia: International Quiz 2022


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Special DX Test via WCGA: May 1, 2022 at 04:00 UTC

Many thanks to SWLing Post contributor Loyd Van Horn at DX Central who writes:

Wanted to share this with you…..our final DX Central Live stream for season 2 will coincide with the upcoming WCGA-GA DX Test coming Saturday night/Sunday morning. You should have a GREAT shot at hearing this one….would love to have you join us for the livestream, too, if you can make it!

The link to the release with all of the details can be found below….

FOR IMMEDIATE RELEASE

Apr 28, 2022

The Courtesy Program Committee (CPC) of the National Radio Club (NRC) and the International Radio Club of America (IRCA) is pleased to announce a special DX Test for distant listeners for WCGA on 1100 kHz in Woodbine, GA. The test is scheduled for 5/1/2022 at 12:00:00 AM Eastern Time (0400 UTC Sunday, May 1st).  This test is scheduled to run for 2 hours.

For WCGA, Wesley Cox, will be performing regular maintenance of the station’s audio chain and transmitter during the test. Listeners will hear: Morse Code IDs at 10 WPM at 800 Hz, Morse Code IDs at 20 WPM at 1000 Hz, Tone Sweeps, Long duration tones at 1 kHz, Off-hook Telephone Sounds, Voice IDs and more.

WCGA will be operating on a full daytime power of 10,000 watts during the test on their daytime antenna pattern.   This should aid DXers across the country and indeed the world in being able to receive this test!

RECEPTION REPORTS & QSL REQUESTS

WCGA is actively soliciting reports from DX’ers on their signal. They’re interested in hearing about frequency stability, audio quality, and overall performance. The station will accept both hard copy reports via USPS mail and email reports. They would love to receive audio recordings in either .WAV or.MP3 and videos in .MP4 video.

Reception reports should go directly to:

Wesley Cox

Owner/General Manager

News/Talk 1100 WCGA

714 Narrow Way

St. Simons Island, Georgia 31522

[email protected]

Physical QSL card senders will receive a physical QSL. Email QSLs will receive email QSL.

Best audio narrative recording and received via email in MP3 or MP4 about themselves and their passion for radio that includes their reception of WCGA and the who, what, when, where, why and how of that event taking place will receive a special prize from the station. DX’ers who submit recordings must grant permission to broadcast their recordings. The decision of WCGA staff on the winner is final.

The IRCA/NRC CPC would like to thank the owners of WCGA, Wesley Cox, and Hall of Fame DXer, Jim Renfrew, for helping to arrange the test.

Good luck to all DXers!

About the CPC

The Courtesy Program Committee (CPC) is a cross-functional group comprised of members of both the National Radio Club (NRC) and International Radio Club of America (IRCA) for the purpose of coordinating and arranging DX Tests with AM radio stations.  These DX tests both allow radio stations to conduct valuable equipment tests on their transmitter and audio chain as well as enable DX hobbyists to receive the testing station from greater distances than would normally be possible.  The CPC membership consists of:  Chairman Les Rayburn, Paul Walker, George Santulli, Joe Miller and Loyd Van Horn.

For radio stations interested in coordinating a DX test with the CPC, please visit the following Web site for more information:

https://amdxtest.blogspot.com/

For more information on the types of content heard during a DX test, the video  “An introduction to DX Tests” is available at DX Central:

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International Radio Club’s Reprints collection of 900+ articles

Many thanks to SWLing Post contributor, Nick Hall-Patch, who shares the following announcement:

The International Radio Club’s Reprints collection of 900+ articles about antennas, radio propagation, receivers, accessories, plus items of general interest to MW DXers, continues to grow.   We’ve published an update to the index, at https://www.ircaonline.org/editor_upload/File/reprints/irca-reprint-index.pdf  ,  so that everyone can get access to these latest additions.

We’re also pleased to start offering reprints that did not initially appear in IRCA’s DX Monitor, but are not easily found elsewhere.  For example, we’ve obtained permission from the family of the late prolific author, Dallas Lankford, to organize and republish his out of print articles. 

(if you’ve used the index before, you may need to refresh the browser page to see the latest update, dated December 2021)

Click here to check out the IRCA Index (PDF).

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