Category Archives: Mediumwave

“Music On The Move” explores portable audio technology developments over the decades

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Many thanks to SWLing Post contributor, Ed, who writes:

Last night on my bedside radio I heard on BBC World’s ‘The Forum’ a wonderful 49-minute piece about portable audio. Much of it covers the earliest portable electron tube radios and transistor radios, and their influences on society in different countries. Mediumwave, Shortwave and FM radios and stations are discussed, as well as evolving technologies. The societal impact of the Compact Cassette and digital audio players and recorders is also discussed. Probably all SWLing Post readers will find this worth listening to!

Cheers,

-Ed

https://www.bbc.co.uk/sounds/play/w3ct5n09

The Forum: Music On The Move

Released On: 22 Jun 2024

Many of us remember the first portable music device we owned: a transistor radio, a boombox, a Walkman or perhaps an iPod. We might even recall the songs we played on it. But we might be less aware of how profoundly audio technology developments from the 1950s to 2000s changed the ways in which we consume music and other audio outside of the home or concert venue. Transistor radios allowed outdoor sounds and noises to mix and compete with those coming over the airwaves, creating new auditory experiences; the cassette player gave the listener a cheap way of making and re-making their own playlists; and the advent of digital music players encouraged us to ‘own’ music recordings without possessing a physical copy of the audio.

Iszi Lawrence discusses the history of portable music with Dr. Annie Jamieson, Curator of Sound Technologies at Bradford’s National Science and Media Museum; American drummer and writer Damon Krukowski; Dr. Jahnavi Phalkey, science historian and Founding Director of Science Gallery Bengaluru, India; Karin Bijsterveld, Professor of Science, Technology and Modern Culture at Maastricht University; and World Service listeners.

Listening In Brazil ZP-30 Radio Station, “The Voice Of Paraguayan Chaco”, AM 610 kHz.

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

Listening In Brazil ZP-30 Radio Station, “The Voice Of Paraguayan Chaco”, AM 610 kHz.

by Carlos Latuff

The first time I tuned on to ZP30 “The Voice of Paraguayan Chaco”, a Christian radio station from Paraguay, was during tests with Innova KV-12002. It was 7 p.m. Brasilia time, and when I turned on the receiver, I came across a medium-wave broadcast with an announcer speaking in German. This surprised me because the medium-wave stations I usually receive at night in Porto Alegre, Brazil, are from Argentina, Paraguay, and Uruguay, and none typically broadcast in a language other than Spanish.

I listened to the news bulletin, entirely in German, and throughout the transmission, I noticed the word “Paraguay” mentioned a few times. I concluded that it must be a Paraguayan radio station broadcasting in German. A quick Google search for radio stations in Paraguay broadcasting in German led me to ZP-30. I found their website, tuned in to the streaming audio, and confirmed I was listening to the same station on my radio.

Check out the ZP-30 website here: https://www.zp30.com.py

At that moment I recorded a video of the radio station playing German songs. I wanted the news bulletin, but I found it quite difficult, either due to problems with propagation, other kinds of interference, or due to a station that operates on the same frequency and that sometimes overpowers the Paraguayan broadcaster.

It took me almost a week to record the news bulletin with decent audio quality, using a ferrite rod AM antenna and my good ol’ XHDATA D-808 receiver.

This station, in addition to German and Spanish, broadcasts news and Christian preaching in languages ??spoken by indigenous communities from the Chaco region in Paraguay.

In Brazil, there was a migration of AM stations to FM, which left the medium-wave spectrum vacant. I believe that, from now on, it will be possible to listen to stations that I had never heard before. Stay tuned!

Some Christian preaching in German:

(Attached a video I made of ZP-30 radio station broadcasting news in German. Porto Alegre, June 4, 2024)

Japan: Some broadcasters running trial suspension of AM radio

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(Source: Japan Today)

Is Japan witnessing the death of AM radio?

Since February, some commercial radio broadcasters have begun a trial suspension of AM radio, with a real possibility the pause will extend to a permanent discontinuation across the country as broadcasters look to cut costs.

Thirteen of the 47 commercial operators in Japan have shut off their transmitters to see what effect the temporary end of AM broadcasts will have. AM was launched in 1925, bringing Japan into the radio broadcast age, but may not last long enough to see its 100th anniversary next year.

“Radio was at the center of the home, a medium enjoyed by the entire family,” said Tadanobu Okabe, curator of the Japan Radio Museum in Matsumoto, Nagano Prefecture. [Continue reading…]

The Giant Antennas of Shanghai Coast Radio Station (XSG)

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Many thanks to SWLing Post contributor, Michael (BD4AAQ) who shares the following guest post:

Shanghai Coast Radio Station (XSG):

Those Giant Antennas!

The 17th of May is the World Telecommunication Day. It is also the open day of Shanghai Coast Radio Station. On this day, a group of amateur radio operators were invited to visit the transmission facility, a huge antenna farm, of the radio station, located on Chongming Island of Shanghai, the third largest island in China.

Google Satellite Photo

The transmission site of Shanghai Coast Radio Station is as shown below in the map of Chongming Island. Other sites of the station include a central control/receive station in Zhangjiang, a receive station on Hengsha Island and some VHF base stations in a number of other locations. All these locations in Shanghai, linked via cable and microwave connection, form Shanghai Coast Radio Station, also known by its callsign as XSG.

(Google map of transmitter location for Shanghai Coast Radio Station. Note the antenna farm on the left.)

Presentation by Station Officials

Fifteen or so local hams were cordially invited to have a tour of the station. The radio enthusiasts were greeted by station representatives, including Mr Wan, Mr Wang, Mr Zhou and Mr Niu (BH4BFS), who also gave them an overview of the coast radio station’s history and development. 

Antenna Farm

Mr Wang then showed the visitors around the antenna farm. Many of us, myself included, saw and were deeply impressed with these huge antennas for the first time! Indeed, many professional radio facilities and operators of similar coast radio stations work quietly around the globe and around the clock to provide for distress, navigational, business and personal communications needs of ships!

[Click on images to enlarge.]

The antennas cover a wide range of frequencies, from MF, HF, to VHF and UHF. Many of them are, however, shortwave (HF) antennas.

Transmitter Room

(I placed a Tecsun PL-330 radio near the transmitter at 12380.1 kHz (weather fax). The signal strength, in dbu, is 96. Given the margin of error of the receiver’s display, that’s probably as high as it could go.)

Shanghai Coast Radio Station (XSG) operates on a wide range of frequencies. Its HF frequencies include 4207.5, 4209.5, 4215.5, 4369, 6312, 6326, 6501, 8414.5, 8425.5, 8770, 8806, 12577, 12637.5, 13176, 13188, 16804.5, 16898.5 and 17407 kHz. Of particular note is that they have kept a CW frequency of 8665 kHz for general broadcast of information on a 24 hour basis.

The station’s VHF phone service covers 25 nautical miles of the coast. Its MF NAVTEX covers 250 nautical miles of the coast. And its HF phone and weather fax and HF NAVTEX extend to 1,000 nautical miles.

History and Current Status

Founded in 1905, Shanghai Coast Radio Station has been around 119 years. The XSG callsign has since remained in use.

China has in place DSC watch and NAVTEX broadcast in coast stations (including XSG) in accordance with GMDSS requirements. Among services provided by XSG are Radio Telephony (RT), Narrow Band Direct Printing (NBDP), “Voice of the East China Sea Coast” (voice broadcast on 161.600 MHz and 8806 kHz) and marine radio weather fax. The station is without a doubt one of the largest coast radio stations in the Asia Pacific region and plays an essential role in the region’s marine safety and communications.

QSL Cards

Shanghai Coast Radio Station issues QSL cards in Chinese and English, traditionally in paper form and nowadays electronically.

(This is an electronic QSL card issued to a Shanghai listener, who received their signal over the radio. Examples of QSL cards in English can be found online.)

Show Room

[Click on images to enlarge.]

Ham Station

Mr Niu of Shanghai Coast Radio Station, one of the tour’s organisers, is a ham himself with callsign BH4BFS. According to him, there are intentions to start a ham radio station within the establishment, possibly incorporating the letters XSG. However, there is much work to be done to make it happen. An amateur radio station with overlapping callsigns with a professional one would be really charming.

Announcing the new SDRplay RSPdx-R2 software defined radio!

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Many thanks to SWLing Post sponsor and supporter, SDRplay, who shares the following announcement:

SDRplay announces the RSPdx-R2 

SDRplay Limited is announcing the launch of the RSPdx-R2 which is an enhanced version of its highly popular multi antenna port SDR, the RSPdx.

Jon Hudson, SDRplay Sales and Marketing Director said “Global supply chain support issues have prompted some  redesign of existing products to ensure continued supply for our UK manufacturing partners. With each new member  of the RSP family, SDRplay tries to include improvements. This has given us the opportunity to offer performance  enhancements at the same time as assuring supply”.

The RSPdx-R2 provides up to 10MHz spectrum visibility anywhere from 1kHZ to 2GHz with no gaps. It features:

  • Improvements to the RSPdx for MF frequencies and below:
  • Improved noise performance below 1MHz
  • Improved dynamic range below 2MHz both in tuner mode and HDR mode
  • 3 Software selectable inputs, including a BNC input for up to 200MHz
  • A 500kHz LPF for LF/VLF
  • HDR mode for enhanced performance under 2MHz
  • Notch filters on all inputs
  • A rugged steel case

More details on https://www.sdrplay.com/rspdxR2/ 

The suggested retail price is £188.00 GBP (excluding VAT), $235.00 USD (excluding tax) or €225.60 EUR (excluding tax).

SDRplay recently launched their free multiplatform SDRconnect software which as well as running on Windows, will  also run on MacOS and Linux/Raspberry Pi. As with their SDRuno windows software, the emphasis is on “plug and  play” making the SDRplay receivers an easy-to-use and low-cost way to discover (or rediscover) the radio hobby for  anyone who already uses a computer.

The UK manufactured RSP family of SDR receivers are available directly from SDRplay Ltd. or from authorised resellers  worldwide. More details on https://www.sdrplay.com/purchasehome/ 

For more information visit the SDRplay website on www.sdrplay.com

About SDRplay:

SDRplay limited is a registered UK company, with registered offices in the UK and Ireland. UK: SDRplay Limited, 21 Lenten Street, ALTON, Hampshire, GU34 1HG, UK, Registered Number: 09035244 Ireland: The Black Church, St Mary’s Place, Co. Dublin, D07 P4AX, Ireland, Registered Number: 3591295EH Correspondence Address: PO Box 1180, Princes Risborough, HP22 9TD, United Kingdom

Video

Click here to view on YouTube.

Data Sheet

Click here to download the RSPdx-R2 Data Sheet. (PDF)

Radio Waves: HEBA Antenna Approval, Eclipse Time Signal Shift, A Novice’s Guide to Amateur Radio Astronomy, and Voyager 1 Sending Data Again!

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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!

Many thanks to SWLing Post contributors Alan, Dan, and Rich Cuff for the following tips:

WQVR(AM) Is Granted CP to Use HEBA Antenna at Night (Radio World)

Developer believes antenna’s smaller footprint can help reduce property needed for AM operators

The FCC in March granted an application for a construction permit filed by WQVR(AM) 940 in Webster, Mass., requesting licensed nighttime operation.

This is noteworthy because WQVR has been licensed to operate during daytime hours with a High-Efficiency Broadband Antenna or HEBA, developed by Worldwide Antenna Systems. [Continue reading…]

Global ‘time signals’ subtly shifted as the total solar eclipse reshaped Earth’s upper atmosphere, new data shows (Live Science)

During the historic April 8 total solar eclipse, a government radio station in Colorado started sending out slightly shifted “time signals” to millions of people across the globe as the moon’s shadow altered the upper layers of our atmosphere. However, these altered signals did not actually change the time. [Continue reading…]

Nathan Butts: A Novice’s Guide to Radio Astronomy (YouTube)

NASA’s Voyager 1 Resumes Sending Engineering Updates to Earth (NASA JPL)

An artist’s concept of NASA’s Voyager spacecraft. Credit: NASA

After some inventive sleuthing, the mission team can — for the first time in five months — check the health and status of the most distant human-made object in existence.

For the first time since November, NASA’s Voyager 1 spacecraft is returning usable data about the health and status of its onboard engineering systems. The next step is to enable the spacecraft to begin returning science data again. The probe and its twin, Voyager 2, are the only spacecraft to ever fly in interstellar space (the space between stars).

Voyager 1 stopped sending readable science and engineering data back to Earth on Nov. 14, 2023, even though mission controllers could tell the spacecraft was still receiving their commands and otherwise operating normally. In March, the Voyager engineering team at NASA’s Jet Propulsion Laboratory in Southern California confirmed that the issue was tied to one of the spacecraft’s three onboard computers, called the flight data subsystem (FDS). The FDS is responsible for packaging the science and engineering data before it’s sent to Earth.

The team discovered that a single chip responsible for storing a portion of the FDS memory — including some of the FDS computer’s software code — isn’t working. The loss of that code rendered the science and engineering data unusable. Unable to repair the chip, the team decided to place the affected code elsewhere in the FDS memory. But no single location is large enough to hold the section of code in its entirety.

So they devised a plan to divide the affected code into sections and store those sections in different places in the FDS. To make this plan work, they also needed to adjust those code sections to ensure, for example, that they all still function as a whole. Any references to the location of that code in other parts of the FDS memory needed to be updated as well.

The team started by singling out the code responsible for packaging the spacecraft’s engineering data. They sent it to its new location in the FDS memory on April 18. A radio signal takes about 22 ½ hours to reach Voyager 1, which is over 15 billion miles (24 billion kilometers) from Earth, and another 22 ½ hours for a signal to come back to Earth. When the mission flight team heard back from the spacecraft on April 20, they saw that the modification worked: For the first time in five months, they have been able to check the health and status of the spacecraft.

During the coming weeks, the team will relocate and adjust the other affected portions of the FDS software. These include the portions that will start returning science data.

Voyager 2 continues to operate normally. Launched over 46 years ago, the twin Voyager spacecraft are the longest-running and most distant spacecraft in history. Before the start of their interstellar exploration, both probes flew by Saturn and Jupiter, and Voyager 2 flew by Uranus and Neptune.

Caltech in Pasadena, California, manages JPL for NASA.

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