Category Archives: Mediumwave

Radio Waves: The Discovery Dish Pre-Launch, China Radio International, Hackaday Prize, and Baseball 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!

Many thanks to SWLing Post contributors Dennis Dura and Ulis (K3LU) for the following tips:

Discovery Dish Pre-launch: A Lightweight Dish And Feed For L-band Weather Satellites And Hydrogen Line Reception (RTL-SDR Blog)

For the past few years we have been working on finding the best way to help beginners get started with L-band weather satellite reception and basic radio astronomy. We have now come up with a solution that we’re calling the ‘Discovery Dish’ – a lightweight 65 cm diameter dish and active filtered feed set.

The Discovery Dish will be crowd funded, and we currently have a pre-launch page set up on Crowd Supply. So if you are interested, please visit the pre-launch page and click on the Subscribe button for updates.

Discovery Dish is a 65-cm diameter aluminum satellite dish and active filtered feed designed for receiving GOES HRIT, GK-2A LRIT, FengYun LRIT, NOAA HRPT, Metop HRPT, Meteor M2 HRPT and other weather satellites that operate around 1.69 GHz. The dish is designed to weigh under one kilogram, and it splits into three petals, making it easier to ship worldwide. The 1.69 GHz feed contains a built-in LNA right at the feed point, as well as filtering, which means that there is almost no noise figure loss from cables or connectors.

Note that the prototype images show an early non-petalized prototype with rough laser cut wind holes. The production version will obviously be a lot neater looking! […]

Click here for more details about the Discovery Dish campaign.

How China’s Propaganda Infiltrated Radio Stations in Europe (The Diplomat)

State-owned China Radio International is airing its content without attribution on commercial radio stations in Europe.

China has consistently and systematically pursued the dissemination of its narratives on the global stage, with the primary aim of shaping the international landscape to align with its strategic interests and ideological perspectives. These endeavors encompass a diverse array of tactics, including the acquisition of media enterprises, active engagement by Chinese ambassadors in both mainstream and fringe media outlets, the utilization of paid supplements, collaboration with pro-Kremlin media, and the steadily expanding presence of China across various social media platforms.

Recently, China Radio International (CRI), an official Chinese state media outlet broadcasting in multiple languages, has garnered attention for its establishment of partnerships with and provision of content to radio stations worldwide. Remarkably, CRI has effectively outsourced the production of China-related programming to local partners, often without transparently disclosing the sponsorship of content creation to the listeners. This strategy, known in Chinese as “borrowing a boat to go out on the ocean,” plays a pivotal role in laundering Beijing’s propaganda and fostering the acceptance of its messaging among local audiences.

One illustrative case of this approach within Europe involves two Czech radio stations, namely Radio HEY, a nationwide commercial radio station airing rock music, and Radio Color, which positions itself as “one of the last independent radios.” From 2019 to May 2023, these radio stations broadcasted a program titled “Barevný sv?t” (Colorful World), a nearly 30-minute segment aired six times a week, with the objective of acquainting Czech listeners with Chinese culture, language, and history. [Continue reading…]

Hackaday Prize 2023: A Software-Defined Radio With Real Knobs And Switches (Hackaday)

When cheap digital TV dongles enabled radio enthusiasts to set up software defined radio (SDR) systems at almost zero cost, it caused a revolution in the amateur radio world: now anyone could tune in to any frequency, with any modulation type, by just pointing and clicking in a computer program. While this undoubtably made exploring the radio waves much more accessible, we can imagine that some people miss the feeling of manipulating physical buttons on a radio while hunting for that one faint signal in a sea of noise. If you’re one of those people, you’re in luck: [Kaushlesh C.] has built a portable, self-contained SDR system with real knobs and switches, called SDR Dock 1.0.

The heart of the system is a Raspberry Pi running GQRX, an open-source SDR program that supports many different RF modules. [Kaushlesh] used an Airspy HF+ Discovery, a compact receiver that can work the HF and VHF bands, but it’s easy to modify the SDR Dock to accept other types like those ubiquitous RTL dongles. A seven-inch LCD screen with integrated speakers forms the main output device, with everything powered by a 10,000 mAh lithium-polymer battery. [Continue reading…]

With the future of AM unclear, a look back at the powerful role radio plays in baseball history (Citizen Tribune)

Many baseball fans, especially older ones, originally fell in love with America’s pastime by listening to ballgames on AM radio

Click here to browse this gallery.

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The Great Medium Wave Grey Line Challenge

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By Jock Elliott, KB2GOM

According to https://dx.qsl.net/propagation/greyline.html: (the image above comes from them)

The “grey line” is a band around the Earth that separates daylight from darkness. Propagation along the grey line is very efficient. One major reason for this is that the D layer, The “grey line” is a band around the Earth that separates daylight from darkness. Propagation along the grey line is very efficient. One major reason for this is that the D layer, which absorbs HF signals, disappears rapidly on the sunset side of the grey line, and it has not yet built upon the sunrise side. Ham radio operators and shortwave listeners can optimize long distance communications to various areas of the world by monitoring this band as it moves around the globe. which absorbs HF signals, disappears rapidly on the sunset side of the grey line, and it has not yet built upon the sunrise side. Ham radio operators and shortwave listeners can optimize long distance communications to various areas of the world by monitoring this band as it moves around the globe.

Elliott’s short version: Some funky stuff can happen with propagation when the grey line is passing through your location.

So let’s have some fun for a couple of hours chasing MW DX along the grey line.

Here are the rules:

Frequency range is the medium wave band: 520-1710 kHz
From one hour before Civil Twilight your local time on Saturday, October 14, to one hour after Civil Twilight at your location.
Any radio with any antenna, but must be the radio at your location (no using remote internet radios)
The listener must hear the signal in real time
The stations must be ID’ed by listening to the signal.
Your report should include:
- Your name (or Internet handle)
- Your receiver and antenna (stay with the same setup from beginning to end; if you use multiple setups, provide a separate report for each).
- Your location
- The time, the frequency, and the ID of each station heard
- The total mileage of your top five most distant stations.

A final point: this is not a contest; it is a challenge. The reward for every participant will be fun and fellowship.

You can find when Civil Twilight begins at your location by visiting www.wunderground.com . Enter your location, click on “Full Forecast” then scroll down to the “Astronomy” section.

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Please Share: Introducing the “I listen” project

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By Jock Elliott, KB2GOM

To paraphrase a line from John Fitzgerald Kennedy: “Ask not what your station can do for you, ask what you can do for your station.”

Think of this as a reverse QSL program . . . but I get ahead of myself.

I was perusing the news a while back, reading about the closure of radio stations in the U.S. and how e-vehicle manufacturers did not want to include AM (MW) radios in their vehicles . . . and . . . I snapped.

“The reason they are closing,” I snarled, “is that they think no one is listening . . . but WE listen!”

So I offer, for your consideration, a modest proposal . . . the “I listen” project.

Let’s do this!

All I ask is that each and every one of you who reads this is that you send a postcard or a letter to your favorite station – AM, FM, or shortwave – that says in BOLD letters at the top I LISTEN! Further down on the postcard or letter, you should explain what you listen to, and what you enjoy.

So here would be a sample from me:

From: Jock Elliott, Upstate New York

To: Talk 1300 AM & 98.7 FM WGD, 11 Dennis Terrace
Schenectady, New York 12303

I listen!

To Talk 1300

To the Jack Catham show because I really like the calm way he presents the issues and interacts with callers.

That’s it. Of course, if you want to send more than one postcard or letter, great!

The point is to let the station know without a doubt that you listen. Why a postcard or letter? Because it is a physical piece of mail that is hard to ignore. By contrast, an email or a text is much easier bypass or ignore.

So make sure that your favorite station or two knows that you listen, and let me know here.

I’ll end by paraphrasing Arlo Guthrie: “Can you imagine fifty people a day, I said fifty people a day, sending “I listen” postcards to their favorite stations? And friends, they may think it’s a movement!”

And bear in mind, this is not the time to be asking for goodies in return.

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How DXers can contribute to ionospheric research during the October 14, 2023 solar eclipse!

How DXers can contribute to ionospheric research during the 14 October 2023 solar eclipse

There will be an annular solar eclipse on 14 October, 2023 when, at totality, the size of the Moon’s disk will appear slightly smaller than the size of the Sun’s disk. This eclipse will affect all of North America, as well as Central and part of South America, as seen in the map below.

AM Broadcast Band DXers know that the blocking out of radiation from the sun during a total solar eclipse can introduce temporary night time listening conditions over an area far beyond the path of totality.

The upcoming annular eclipse is expected to have a similar effect on daytime medium wave listening conditions as would a total solar eclipse, and should not be missed by DXers. Live listening can be done during the eclipse, as well as recording the entire medium wave band, using SDRs (software defined radios).

There might be more to our DXing results than new and unexpected receptions of distant radio stations, however. The rapidly changing listening conditions will be indicating a similarly turbulent ionosphere, and DXers’ documenting those listening conditions through SDR recordings could provide information that will be useful to scientists who want to gain a better understanding of the Earth’s ionospheric dynamics.

How can DXers contribute to ionospheric research?

HamSCI is an organization of volunteer citizen-scientists and professional researchers who study upper atmospheric and space physics, and will be interested in examining MW DXers’ wideband SDR recordings made during both eclipses, and indeed, in having DXers assist with HamSCI’s research.

It will be important to have many participants in this project. To sign up, please go to https://hamsci.org/mw-recordings/ and discover how to make sure that those DX files will also qualify as scientific data that can become part of the public record.

Those interested in finding out about all the research that HamSCI will be doing during the upcoming eclipses, check out https://hamsci.org/eclipse . Especially if you are also an amateur radio operator, there are several other ways that you might contribute to the project.

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Don Moore’s Photo Album: Costa Rica (Part One)

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Radio Reloj, Costa Rica (1990)

Many thanks to SWLing Post contributor, Don Moore–noted author, traveler, and DXer–for the latest installment of his Photo Album guest post series:

Don Moore’s Photo Album: Costa Rica (part one)

by Don Moore

Costa Rica is one of the most visited countries in Latin America. I only visited there once, for three weeks in May-June 1990 when the country was just beginning to become a major international eco-tourism destination. Visitors were few and prices very affordable. Except for a short trip to the Monteverde cloud forest, we spent all our time in the central valley, staying in San José and nearby Heredia. Rather than nature, our visit focused on cultural and historical sites … and a lot of radio stations.

Since the 19th century, Costa Rica has been one of the most literate and educated countries in Latin America. That quality is reflected in its radio broadcasting industry, which has always been very professional. Curiously that’s even reflected in station verifications. Almost every Costa Rican shortwave station that I’ve verified had a professionally printed QSL card.

Despite being one of the smallest countries in Latin America, Costa Rica had a lot of shortwave radio stations. I have fifteen in my logbooks and some of the most famous ones were already off the air when I started DXing. Unfortunately, shortwave broadcasting from Costa Rica ended almost twenty years ago so there’s no more to be had. It is still possible to log Costa Rica on medium wave but it’s not as easy as it once was. When I started DXing in the early 1970s, stations in the San José were spaced twenty-five kilohertz apart. That meant that every other station, such as Radio Sonora on 675 kHz and Radio Columbia on 725 kHz, was on a split frequency that fell between the normally assigned 10 kHz channels. I logged nine Tico stations on medium wave while DXing from Pennsylvania in 1972-1981 and only one of those, Radio Reloj on 700 kHz, was on an even channel. Those split channels were eliminated in the 1980s so logging Costa Rica on medium wave is no longer a slam-dunk.

I visited a lot of radio stations and took a lot of photos on my one long-ago trip to Costa Rica. I’m going to focus on just five shortwave broadcasters in this first look at Costa Rica. The others will be featured in two or three future columns.

In the 1970s the first Costa Rican station most shortwave DXers heard was Faro del Caribe, or Lighthouse of the Caribbean. This religious station used two kilowatts on 9645 and 6175 kHz and got out surprisingly well as long as there wasn’t a more powerful international broadcaster also using the same frequency. In the late 1970s they added 5055 kHz in the sixty-meter band.

When I visited in 1990 the antennas were located right next to the studio building. The site was outside the city of San José when the station was founded but gradually a residential area built up around it.

Engineer checking one of Faro Del Caribe’s shortwave transmitters.

Fortieth Anniversary pennant from 1988. When Faro del Caribe began broadcasting on February 23, 1948, it was the first Evangelical Protestant radio station in Central America.

For DXers, Radio Reloj was one of Costa Rica’s best known radio voices for several decades. The station was founded as Radio Cristal by Roger Barahona in 1945. The shortwave frequency of 6006 kHz was added in the early 1950s. In 1958 the station was renamed to Radio Reloj when the format changed to focus on news and community announcements with very frequent time checks. (Radio Reloj means Radio Clock.) Roger’s brothers Isaac and Francisco had joined the broadcasting company and Radio Reloj was assigned the callsign TIHB for Hermanos Barahona (Barahona Brothers). Continue reading →

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Guest Post: A review of the Chaoyuan LC90 Hybrid Shortwave/4G/Internet Radio

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

The LC90, a Great Radio Spanning Two Worlds

by Michael Ye (BD4AAQ)

It is an awkward era for radio receivers. Although technology becomes more and more advanced and increasingly sophisticated radios are made, there are fewer and fewer stations to listen to. But hardcore radio hobbyists, mostly hams and shortwave listeners, would not give up the hobby. They continue to look for and enjoy stations among noises in the airwaves. Although Internet radios have been around for a long time, I never thought seriously about them. Perhaps I was stubborn, but in my mind, radios were noises and noises were radios and it’s the stations among the noises that I enjoyed. Receivers without noises were hardly real radios.

Until I got my first full band radio with Internet features. The LC90 was a pleasant surprise, completely changing the way I look at radio receivers. The LC90, or “full band smart Internet radio”, is my first shortwave radio AND Internet radio in one. There may be other radios with Internet features, but I have heard of few receivers that integrate the traditional radio (shortwave in particular) and the Internet. The LC90 was launched in China in early 2023, and quickly became popular among hobbyists thanks to the unique combination. News has been confirmed that the overseas version of the LC90 will be launched later this year. It provides more options for users at a time when shortwave broadcasters continue to shut down transmitters and bid final farewell.

Chaoyuan Company

The manufacturer of the LC90 is Chaoyuan, an electronics company based in Shenzhen, China, known for mobile phone design and Hi-Fi equipment. In recent years they started to design and make radios. And they are serious about the business, too.

The LC90 full band smart Internet radio

The Radio at a Glance

The radio is of regular size. A computer mouse is placed in the picture above, so you have an idea of not only the radio’s looks but also its size. The exact dimensions are 22x122x40mm. Its weight is 640 grams. The radio has a built in 4G SIM card, with 3G prepaid data. You have to add credit to the card in time by scanning a QR code on the screen before the built-in SIM card expires. You can also use your own SIM card by inserting it to a slot at the bottom of the radio. And of course, you could use Wi-Fi at home.

Although the radio is a combination of the traditional radio and the Internet, it is very ingeniously designed and does not put off the user with too many bells and whistles – you could press the tuning button to change the shortwave band and the fine tuning button to change the band width. The tuning button also serves as an “enter” key. These are clever designs that effectively save extra buttons. I have not seen a similar design in other radios.

For those who do not read Chinese, the upper five buttons are, roughly, “Configure”, “Timer”, “Setup”, “History” and “Favorites”. The four buttons on the left: “Confirm”, “Stations”, “News” and “Menu”. The four buttons on the right: “Back”, “Sequence”, “Rewind” and “Fast Forward”. The button with a globe says “Internet”.

The radio has excellent audio quality, rich bass, with a well-balanced frequency response. It is powered by two 18650 rechargeable lithium batteries. The radio has no back stand.

Traditional Radio

All three modes (or bands) are available, FM, MW and SW, as shown in the three buttons on the upper right (to get LW just press MW again). The FM band covers 64-108MHz, which includes Japan’s FM band. During the FMDX season you could have stations from Japan and other countries to explore. The SW band covers 2300-26100KHz, continuous, almost the entire shortwave band, more than enough for broadcast listening. The antenna jack works for all three modes (or bands).

Excellent Shortwave Performance

As a shortwave listener of many years, I am most interested in the radio’s performance in shortwave reception. Well, it is indeed very good in terms of sensitivity, selectivity and audio quality, with no compromise although the radio has an Internet section which requires additional space and resources.

When you use the radio indoor, reception could be poor and you can insert an external antenna to the antenna jack. Unfortunately, I cannot connect my AOR LA400 loop antenna to it as the antenna jack is too close to the tuning knob and so there is not sufficient space for the plug (see picture). Generally, a 3.5mm plug with a wire should work well if you extend the wire outside.

The external antenna jack

If there is a disappointment, its shortwave reception does not decode SSB signals. If the user is not a ham radio hobbyist, SSB reception may not be really needed anyway and the buttons, circuits and space can be saved accordingly.

Fair FM Reception

FM reception is good, but there is no obvious improvement of reception when an external plug is inserted in the antenna jack.

Mediocre MW Work

Reception on the lower bands, e.g., the medium wave band, is always a challenge in cities. It is not surprising that medium wave performance of the LC90 is mediocre at best. I don’t do much MW DXing but nowadays for each MW frequency there is almost always an FM frequency. Let’s face it – we should perhaps forget about medium wave reception in cities where there is excessive low band EMI.

However, if you go outdoor with the radio, medium wave reception can still be a lot of fun. And, contrary to FM reception, an external antenna significantly improves its performance!

Internet Radio

Admit it or not, the best days of traditional radio are gone, and while we continue to have fun on the old time radio, we should not hesitate to embrace newer technologies such as the Internet. By launching the LC90 and combining the two, Chaoyuan has made a significant move.

The Internet radio is an integrator of many online stations on the Internet, and more. It is completely different from the traditional radio which receives radio signals transmitted on air. The Internet radio, which relies on the Internet, provides much better audio quality, no noise, customizable and replay-able.

If you want to kill time and look for signals from noises, turn to shortwave and enjoy DXing. If you feel like listening to solid content or enjoying noise-free music, the Internet radio is there for you. This Internet radio integrates major web stations in China and on that basis the user can further select and configure their own favorites. Among apps that are built-in is Ximalaya FM, the leading audio platform in China. Due to requirements of policies and regulations in China, the user does not have much discretion to include foreign stations in the radio. However, Chaoyuan has indicated that they are working in an effort to secure authorizations from Spotify, Alexa and Pandora which they hope could be incorporated in the overseas version of the LC90. The future overseas version is expected to give the user more discretion to include online stations of their own choice.

A closer look at the display of the Internet Radio

Two buttons, Ai1 and Ai2, are voice assistants. Activate and speak to them and the radio directly plays the content (Ai1) or displays their findings for you to choose from (Ai2).

Finally, this is a radio with the most accurate time. There is no need to set the time for it, as it is based on the Internet.

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Sometimes simple works . . . really well! Exploring the CCrane EP PRO

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By Jock Elliott, KB2GOM

This particular adventure began about three weeks ago with an email from CCrane. “Timeless, Easy to Use with Long Range Radio Reception” the headline read. Further, the accompanying text promised: Comes with needle and dial tuning, one button for power, one button for a bright display light, and has no clock or alarm. The radio in question was the C.Crane CCRadio-EP PRO.

The “Long Range Radio Reception” initially caught my eye, but the simplicity of an old-fashioned “needle and dial” – what I call “slide rule” – tuning” also appealed to me, so I emailed CCrane, asked them if they would like to send me one for review, which they did, without charge.

While waiting for the EP PRO to arrive, I examined the photos of the EP PRO on the CCrane website, and I noticed something peculiar: a switch on back for choosing between 9 kHz tuning steps and 10 kHz tuning steps. Whaaat?! Why in the world would you need such a thing on a radio with needle and dial tuning?

We’ll get to the answer to that question shortly, but first let’s take a tour of the CCrane EP PRO.

The case is a rectangle with rounded corners that measures 11.4″ W x 7.3″ H (8.4″ H with handle) x 2.75″ D and weighs 4.5 pounds without batteries. Starting on the left front panel, you’ll find a 5-inch speaker. To the right of that, there is the slide rule (needle and dial) tuning setup, with a small red light on the right side that illuminates when a station is found. Below that is a CCrane logo and further below is a switch for selecting AM (520 – 1710 kHz, 10 kHz steps; 522 – 1620 kHz, 9 kHz steps), FM (87.5 – 108 MHz), or FM stereo; a knob for adjusting bass, a knob for adjusting treble, and a knob for choosing between narrow (2.5 kHz) and wide (6 kHz) filter bandwidths.

On top of the EP PRO are a red POWER button, a black button for lighting the tuning dial, a flip-up carry handle, and a 36-inch telescoping antenna for FM reception. (Inside the case is a ferrite bar antenna – 12mm x 200mm (7.9″) long with CCrane’s Twin Coil Ferrite® technology.)

On the right side of the case at top is the tuning knob, below that a knob for fine-tuning the internal antenna for AM reception, and at the bottom a knob for volume. On the left side of the case, you’ll find a 1/8” stereo headphone jack, a line-in jack, and a socket for plugging in an external 6-volt AC adaptor which is provided with the EP PRO.

On the back of the radio is a hatch for installing four D-cell batteries (CCrane says it will run for about 175 hours at moderate volume with the dial light off), external antenna connections: spring loaded for AM and “F” connector for FM, a switch for selecting internal or external AM antenna, and the switch for selecting 9 or 10 kHz tuning steps.

That’s it. The EP PRO is almost Zen-like in its simplicity. There are no seek buttons, no automatic storage functions, no memories, no key pad. And there is a darn good reason for that. It turns out that the immediate predecessor of the EP PRO, the CCrane EP, was created by Bob Crane because his mother wanted a very simple radio that was easy to operate. The CCrane EP, a true needle and dial analog radio, was the result.

Bob believed that, besides his mother, there was a market for such a radio, and there was. Unfortunately, after a time, the analog chips necessary to build the CCrane EP became unavailable. As a result, the radio was redesigned internally using modern digital chips (essentially the same as those in CCrane’s model 2E and 3 radios) while keeping it simple and easy to operate. So inside what looks like an old-fashioned analog radio beats the heart of a high-performance digital radio that combines the high sensitivity needed to hear distant stations with excellent selectivity to block signals from the side.

In my view, the EP PRO is great fun to operate. In the predawn hours on a weekend morning with the rain falling softly outside, I started tuning slowly across the AM dial with the EP PRO in my lap. Near the bottom end, a couple of sports mavens were chatting about a pitcher who had a couple of rough two initial outings and then had “settled in.”

A bit further up the dial Dionne Warwick was telling me to “walk on by.” Then I ran into a music station competing with a talk show considering “the Bible, angels, and UFOs.”

Up the dial some more, apparently a good deal on a high performance car could be had at a dealership in Connecticut; then an air quality report for New York City, a female voice delivering a long discourse in French and so on up the dial.

I was impressed at the number of stations that the EP PRO was pulling in, and it brought me back to the simple joy of tuning around to see what’s on the air.

Each time a discernible station appeared, the red tuning LED would light up. As needed, I used the antenna tuning knob and the bandwidth selection switch to tweak the signal. The needle and dial tuning gives an approximate indication of where on the band the radio is tuned, so if you want a positive ID, you need to listen for a station ID or some other clue to the station’s location.

At one point I jumped to the FM dial and found I could easily pick up many FM stations even with the whip antenna collapsed. In all, I am of the opinion that both the AM and FM sides of the receiver are pretty “hot,” and at no time did I find myself wishing for an auxiliary antenna for more signal. Further, the sound through headphones or the speaker is very pleasant indeed. In my mind, the relatively unadorned exterior of the EP PRO belies its outstanding performance. To stretch an analogy, it’s a nitro-burning funny car in the body of a Honda Civic, and you don’t have to be a genius to drive it.

If you’re looking for a high-performance radio that is easy to use and sounds good through speaker or headphones, the CCRadio EP PRO delivers the goods. For a content DXer like me, the EP PRO encourages me to tune around and discover the magic of radio all over again.