Category Archives: Mediumwave

How to DX the 2024 Solar Eclipse!

Many thanks to SWLing Post contributor, Nick Hall-Patch, who shares the following article originally published in the IRCA’s DX Monitor:


2024 Solar Eclipse DXing

by William Scott, WE7W

DXing the mediumwaves promises to be an exciting event on April 8 during the 2024 total solar eclipse.    I’ve been mulling over the DX possibilities a lot lately and have come to some conclusions. I think it boils down to three promising DX scenarios:

  • Scenario 1. For those who live within or very near the path of totality (see Figure 1), I believe best chances of DX would be first to listen to your southwest, along the path where totality is approaching. Darkness will already have happened in that direction, and a certain amount of residual de-ionization of the ionosphere will still remain. After the point of totality passes your location, I would swing my attention to the northeast.
  • Scenario 2. For those living within about 800 km (or about 500 miles) of the path of totality I believe best chance would be a perpendicular path across the totality path to a point roughly equidistant on the other side. This puts the signal reflection point right at the center of the totality path, or the deepest point of darkness.
  • Scenario 3. For those living more than about 800 km from the path of totality I believe best chance would be along a line from your receiving site to a perpendicular intersection to the totality path. This should define the greatest shaded path.

I think that scenarios #1 and #2 have the best possibility for DX.

Figure 1 (Click to enlarge)

Across the U.S. and Canada, from its entry at Texas to its exit through NE Canada and into the Atlantic Ocean, the totality path width varies from a maximum of 199 km at U.S. entry to about 160 km at Atlantic exit, or 123 to 99 miles.

Important to keep in mind – skywave signal strength analysis is based almost entirely on the condition of the ionosphere at the reflection point, not at the receiving site. For single hop propagation, normally the reflection point is at the halfway point to the station along the great circle route.    That 800 km distance from the totality center I wouldn’t hold as gospel. I’m throwing that figure out as a point where scenario #2 may start to transition to scenario #3.

Timing is of the essence for DXing. The shadow velocity exceeds 1000 mph, increasing from 1587 miles per hour at Eagle Pass, Texas to 3176 mph at Houlton, Maine. You may have only minutes to DX.     I’ll be in Rochester, NY at the time of totality, and we are right at dead center. I’ll be scenario #1. My plan is to listen to my southwest initially, where totality is approaching. I’ll be listening particularly for WLW-800 in Cincinnati, OH, WHAS-840 in Lexington, KY, and others along or near that path.

Scenario #2 possibly holds the most promise. Calculate your distance to the path center line and look for stations on a direct line across the totality path and at an equal distance on the opposite side of the path from you. One such scenario might be WSB-750, Atlanta to a reception point in northwestern Illinois, central Iowa, or southern Wisconsin or southern Minnesota. Many possibilities on cross-paths exist here. I feel best results would be with a signal path that crosses the path of totality closest to 90 degrees.

A question was raised about the possibility of DX from Spokane, Washington, an extreme distance from the path of totality. That particular scenario would be scenario #3, more than 800 km to the path of totality. Maximum obscurity should be when northeast Texas (let’s say the Dallas area) is experiencing full totality, as the great circle line to the totality path intersects at approximately 90 degrees to the line at that point. This would be at about 1848 UTC. I would listen for any signals along a great circle path between Spokane to anywhere from the Dallas area and northward.     Obviously, Spokane to Dallas is an extremely long one hop path, at about 2450 km. At that distance, the reflection point is near Denver, which will have a solar obscuration of 65.1% at maximum.

A Dallas area reception would be next to impossible I would think, but there are many more stations along that great circle path one could try for. Closer stations will obviously move the reflection point closer and start to reduce the solar obscurity. I did a scan along that path and there are some 340 stations within 200 km either side of the line of the great circle path between Spokane and Dallas.

A presumed Scenario #4.

Another scenario was suggested by Nick Hall-Patch, that of reception parallel to the path of totality and outside the 100% totality band. The 2017 solar eclipse across the northern part of the U.S. was DXed extensively and produced some interesting results, which are well documented in IRCA Reprints.  Check their document repository here:

http://dxer.ca/images/stories/2019/irca-reprint-index.pdf

Nick reports: “The receptions of KSL-1160 described in IRCA Reprint # G-096 showed the results of 3 DXers listening across the path of the eclipse (Scenario #2), but the fourth, Dave Aichelman, was monitoring KSL from a location parallel to the eclipse path ( sort of Scenario #1?) and got very good enhancement as well.”    We might name this “Scenario #4”.

I checked out # G-096, that documents the KSL reception from the solar eclipse of 2017. It looks like the Dave Aichelman (at Grants Pass, OR) reception of KSL had a mid-path reflection point of about 95% solar obscurity. The distance was 971 km (602 miles). Graphing KSL, I see it has a nice fat low angle takeoff and impressive skywave strength at 900 km, some 1.3 mV/m for that distance. (ed. note: A map of fractional solar obscuration is in Figure 2, easily converted to the percentage figures quoted in this article. )

Better yet, the article indicated Aichelman also received XEPE-1700 across the Mexican border from San Diego too. That was a mid-point reflection obscurity of only about 83% as far as I can deduct from the maps. The distance was 1238 km (769 miles). The mid-path reflection point there was in the neighborhood of 700 km from the central path of totality.

So, DX is indeed possible where both the station and the receiver are off center from the totality path. It’s looking like anything from at least 80% obscurity at mid-path reflection may have some real possibilities, particularly if you are at the end nearest the path of totality. Lower obscurities, perhaps down to 50% or so may even produce results.

Check out these links.

https://nationaleclipse.com/cities_partial.html

https://eclipse.gsfc.nasa.gov/SEpath/SEpath2001/SE2024Apr08Tpath.html

https://eclipse2024.org/eclipse_cities/statemap.html

Using my pattern mapping program which has extensive area search capability, I’ve compiled a list of all US and Canadian stations that fall within the 2024 Solar Eclipse path of ~100% totality. There are 456 stations. Results are drawn from the March 20 FCC LMS database and Industry Canada database. Sorry I don’t have Mexico available.

If you would like this list, download from this link. https://www.mediafire.com/file/125ih5yrmw4puib/2024-eclipse-stations-by-longitude.zip/file

Across the US and Canada, from its entry at Texas to its exit through NE Canada and into the Atlantic Ocean, the totality path width varies from a maximum of 199 km at US entry to about 160 km at the Atlantic exit off Newfoundland, or 123 to 99 miles.   456 stations are found in this eclipse path. I purposely set the path width to 210 km from start to finish. This gives a few km slop on both sides of the 100% totality path for good measure.

Unzip the downloaded .ZIP file, where you will find 3 files. The stations in each file are sorted by longitude, from west to east. This gives us the progression of the eclipse path, with the eclipse starting at the first station in the list and ending with the last station.

File #1 is a simple text file.

File #2 is in .CSV format. You can easily input it to an Excel file.

File #3 is in .HTML format. It includes links to each station’s Google Map latitude-longitude coordinates for the satellite view of the transmitter tower array.

Another link takes you to the FCC AM Query link for that station.  I hope these files are beneficial. There should be many propagation path possibilities outside of this list as well.

(reprinted from the author’s blog at https://radio-timetraveller.blogspot.com/ )

********

Further sources of information concerning the eclipse include the following websites:

http://xjubier.free.fr/en/site_pages/solar_eclipses/TSE_2024_GoogleMapFull.html?Lat=43.66400&Lng=-76.13690&Elv=88.0&Zoom=6&LC=1

(Clicking anywhere on this map page will give all the information you need about obscuration, length of eclipse etc.at a given location).  Also:

https://www.greatamericaneclipse.com/april-8-2024

https://eclipsewise.com/2024/2024.html

Animations of the path of the eclipse versus time can be seen at:

https://eclipsewise.com/solar/SEanim400/2024_04_08_TSE_400px.gif

http://7dxr.com/4all/100km8Apr-movie–Frissell-HamSCI.mp4

The latter is particularly interesting, as it shows the moon’s shadow at 100km height above the earth, an area of special interest to DXers, as it is the lower edge of the E-region of the ionosphere.  Note especially that as the eclipse ends over the North Atlantic Ocean, that there is a temporary darkness path between Europe and North America, because night will already have fallen in Europe.  So will there be blips of TA DX in eastern North America as the eclipse passes by?   Listen, and find out!

Finally, our DX could be of interest to ionospheric physicists also.   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.

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 the eclipse period, and indeed, in having DXers assist with HamSCI’s research. (see https://hamsci.org/eclipse.  Especially if you are an amateur radio operator, there are several other ways that you might also contribute to the project.)

(This first appeared in IRCA’s DX Monitor and is used with permission.   See https://www.ircaonline.org/default.php for club details)

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Only One Week To Go: HamSCI Presents the Solar Eclipse QSO Party!

Many thanks to SWLing Post contributor, Edward Efchak, who shares the following announcement:


ONE WEEK TO GO!  SAVE THE DATE!!

Monday, April 8TH!!  

HamSCI Presents the Solar Eclipse QSO Party – April 8, 2024

Join with thousands of your fellow amateurs as part of the largest crowd-sourced event for ham radio scientific exploration ever!  The SEQP is part of The Festivals of Eclipse Ionospheric Science and is for learning more about how the ionosphere works. Use any mode, any band for all or part of the day!  Participation can be from everywhere – you need not be near the path of the eclipse to contribute valuable data by participating.

Or just get on the air and help provide the data to better understand the ionosphere.

Save the date – Monday, 8 April 2024

Get on the air! 1400-2400 UTC

Do it for science!! Any band/any mode (except the WARC bands)

HamSCI serves as a means for fostering collaboration between professional researchers and amateur radio operators. It assists in developing and maintaining standards and agreements between all people and organizations involved. Its goals are to advance scientific research and understanding through amateur radio activities and encourage the development of new technologies to support this research.

For more information about HamSCI, please visit the HamSCI website (www.hamsci.org) . For more information about the Festivals of Eclipse Ionospheric Science educational opportunities for the amateur community and the public please visit our information pages.

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DICA 2: “The Revenge” – Giuseppe tests his updated homebrew antenna!

Many thanks to SWLing Post contributor, Giuseppe Morlè, who shares the following antenna project:

Dear Thomas and Friends of the SWLing Post,

I’m Giuseppe Morlè from Formia, central Italy on the Tyrrhenian Sea.

After the DICA prototype I created another one called DICA 2 The Revenge!

This other minimal antenna works differently from the prototype. It is shorter, has 3, 12 cm ferrites inside and has the sensors soldered inside in reverse on the telephone cable strap. It works coupled to a metal surface because it uses magnetic induction unlike the prototype.

In the videos you can see the differences between the prototype and the DICA 2…
and the yield on the highest ranges.

This small minimal antenna can tune listening from 3.5 to 30 MHz.

Thanks to you and greetings to all the Friends of SWLing Post.

73.

Videos

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2024 Eclipse: HamSCI Roundtable Events

Many thanks to SWLing Post contributor, Ed Efchak (WX2R), who shares the following announcement:


The Solar Eclipse Is One Month Away!

Learn How You Can Participate in Two HamSCI Roundtable Events

The last total solar eclipse across North America for twenty years will occur on Monday, April 8th. Hams across North America are asked to participate in learning more about how the ionosphere functions by getting on the air to help scientists in a series of ionospheric experiments.

Connect with HamSCI members and curious hams on Wednesday, March 27 at 8PM (Eastern) / 5PM (Pacific)*, or that same day at 10PM (Eastern) / 7PM  (Pacific)* for a Zoom presentation on HamSCI’s Festivals of Eclipse Ionospheric Science (FoEIS).  The presenters will take your questions during the 30-minute presentations.

The link to these presentations is here: https://scranton.zoom.us/j/286316405?pwd=QWdwMlFPbDlYeXg5ZDg1dmYzeFdCUT09#success

The program will start by covering HamSCI’s basis and purpose, quickly moving into why we are conducting experiments, how hams and SWLS can participate, and what we hope to learn from the event.  Along the way, we will discuss why the science behind the events is important to users of the high frequency radio spectrum – including amateur radio operators!

Learn about the HamSCI’s eclipse-focused operating events:

Solar Eclipse QSO Party (SEQP)

Gladstone Signal Spotting Challenge (GSSC)

Medium Wave Recording Event

Time Delay of Arrival (TDOA) Event

Grape 1 Doppler Receiver project

…and more!

There is no need to pre-register, create an account or log into any site. Simply follow this link at the date and times above to be taken to a Zoom meeting room, hosted by HamSCI:  HamSCI FoEIS Roundtable Zoom Link

Join us on March 27th!!   Get on the air April 8th!!

HamSCI serves as a means for fostering collaboration between professional researchers and amateur radio operators. It assists in developing and maintaining standards and agreements between all people and organizations involved. Its goals are to advance scientific research and understanding through amateur radio activities and encourage the development of new technologies to support this research.

For more information about HamSCI, to join our mailing list, or participate in our work, please visit us at www.hamsci.org.

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John’s In-Depth Review of the Choyong LC90 (Export Version)

Many thanks to SWLing Post contributor and WWLG author, John Figliozzi, who shares the following review:


A Review And Analysis Of The Choyong LC90 (Export Version)

By John A. Figliozzi

General

To my knowledge, this is the first radio to combine AM Shortwave with Internet Radio.  This makes it the first true “full service” radio incorporating ALL of radio’s major platforms.  Many radio listeners question why this hasn’t been done sooner, so this very good first effort is most welcome.

The initial presentation of the radio to the new owner is impressive.  The stylish box in which it arrives is worthy of a respected instrument of high quality.  The radio has the solid substantial feel of a device with excellent build quality.  Its sizing – that of a paperback book along the lines of some previous well-respected AM/FM/SW receivers like the Grundig YB-400 – gives it the perfect form factor for a radio that can be enjoyed both in the home and as a portable.

There is so much to like here.  Over and above its unique combining of Internet radio and shortwave, there’s a “permanent” battery that offers many hours of use before it needs recharging, ATS tuning, the ability to save frequencies and stations in several preference lists, several ways of searching for Internet radio stations, an easy way to add Internet stations not already listed by the manufacturer, and others.

But the LC90 really shines with its fantastic audio on FM and Internet radio.  There’s a woofer, a tweeter and a low frequency diaphragm inside the speaker cavity that occupies the left half the case – and nothing else.  The radio’s excellent build quality and its developers’ efforts to produce a world class audio section in a portable radio really pays off.

But no radio is perfect, and this one obviously is a work in progress.  So, being critical – which is what a review and analysis like this does — should not imply disapproval on any level.  On the contrary, the LC90 is already a well-formed radio worthy of consideration by any purchaser.

The Screen

The screen that is the center of the LC90 provides much information depending on the platform being used.  But in some cases, useful information is missing and in other cases the information provided seems unnecessary or of questionable utility.

In AM (MW), FM and SW, it is not readily apparent what all the symbols mean or why they are there.  The time, signal strength and SNR (signal to noise ratio), bandwidth, meter band, heart (for including a frequency in “favorites”) and the “Freq. vs. Addr.” indicators are all helpful and understandable.  But what is meant by “Memo” isn’t entirely clear.  Is it holding just my preferences?  Or the number of stations found by ATS?  Or something else?

So, too, with the Internet Radio screen.  What do the three dots, the speaker icon and the return icon mean?  The ability to tune stations in sequence as they appear across the bottom of the screen depending on mode is both unique and helpful.  But the use of a timer to tick off how long one might listen to a particular station seems of dubious value.

Some suggestions for better use of the screen in some circumstances are detailed below.

Operation

Initial setup matching the radio to home internet service proceeded flawlessly.  The time clock is in 24-hour mode and showed correct time and date in my time zone.  Some purchasers had previously noted that the clock showed a time one hour earlier than the actual time.  I surmise that this is because the clock remains in standard time year-round.  There is no facility to reset the clock, compensate for seasonal time changes or set the clock manually.  This is an oversight that should be addressed.

This is a sophisticated, multi-faceted radio.  As impressive as it already may be, it should be perceived as a work in progress in need of the improvements it will get eventually through firmware updates and design modifications.  It would be helpful if those updates could come directly and seamlessly through the Internet, something that apparently can’t be done currently.

The LC90 comes with a rather short, almost cryptically worded pamphlet.  This can serve as an ok quick start-up guide.  But after using the radio, it’s obvious that there’s need for a comprehensive operation manual with copious directions for the user, along the lines that Eton provided for the E1.  A radio of this quality and at this price point demands such consideration.

In short, becoming fully familiar with and comfortable using all the features of the LC90 requires a prodigious learning curve, one that is not intuitively discerned.  I have to say that even after using it almost constantly for a few weeks, I feel I am still missing things.

Just a few examples of aspects that go unexplained include:

  • What does “Auto Play” mean in Settings?
  • Getting to preferences (the “heart” icon) is confusing and I’ve inadvertently removed them without learning how it happened.
  • Why does the screen show “Please add radio channel first” when I think I’ve already done that?
  • Why does screen alarmingly show “Saved channels removed”, having done so when I press the tuning dial thinking I am obtaining a list of my preferred or saved stations?

The cleverness behind the LC90 is not intuitively apparent.  If I hit the wrong keys in combination or hard press instead of soft press a key, I get a result I don’t understand and for which there is no explanation in the exceedingly short manual provided now.  In some cases, I put myself in a corner I can’t get out of, so I must reset by shutting down and restarting the radio to get back to base.

Following are my observations on the performance of the LC90 by platform:

FM

The LC90 has a very good FM section that is quite sensitive.   Using the ATS feature, (automatic tuning) it found 37 stations in Sarasota FL, for example.

For its size – and even considering many larger radios — the LC90 has an excellent audio response on FM.  However, although it has activated stereo capability, it does not appear to actually provide stereo through its ear/headphone jack. This is because the same output is used to provide audio to the speakers and the ear/headphone jack.  This feels like an oversight that should be rectified.  The radio does “recognize” a stereo plug and audio does play into both ears.  It’s just not stereo audio.

As currently configured this LC90 does not offer RDBS (RDS in Europe) on FM.  This should be incorporated into a radio of this quality being offered at this price point.

Even so, in this user’s opinion it earns a 4.5 on scale of 5 on FM.  But if it had stereo and RBDS, it would easily earn a 5.

A question arises:   Were HD Radio (in North America) and DAB+ (in Europe and Australia – if these are targeted markets for the LC90) considered for incorporation into this radio by its developers?  If not, why not; and, if so, why was a decision taken not to include them?

Shortwave

Performance of the LC90 on shortwave is very good, especially since it clearly is not intended as a hobbyist’s DX machine.  As such in my opinion, it doesn’t require the SSB capability that some have said they wish it has.

Rather, this radio is intended for the content-focused listener.  I view the AM (MW), FM and SW platforms as back-up alternatives for and secondary to the primary focus — Internet Radio.  Nonetheless, the LC-90’s performance is above average on both FM and SW which should be assuring to anyone considering its purchase.

The LC90 is quite sensitive on SW for a small portable using just its built-in expandable and rotatable 9 stage rod antenna.   But it does especially well when a common clothesline reel external antenna is extended and plugged into the receptacle provided for that purpose on the radio’s right-hand side.  (Similar improvement is noted for AM (MW) and FM, as well.)

Complaints about placement of this receptacle close to the tuning knob is of no concern when an external antenna of the type described above using a 3.5mm plug connector is used.  Any more sophisticated an external antenna would likely overload this radio considering that “birdies” – false signals internally generated by the radio itself — can be detected throughout the SW spectrum even when just using its built-in rod antenna.  This flaw should be addressed in any future modification or upgrade.

The audio enhancements made on this radio through unique use of speakers and their orientation are not as apparent here as they are when listening to FM and Internet Radio.

On AM signals generally — both SW and AM (MW) – a listener can detect artifacts in the audio.  Audible random “clicks” often can be heard – usually when receiving weaker stations – which sounds as if the radio’s audio section is clipping.   Adjusting the bandwidth appears to offer only minimal help with this.

Indeed, the audio produced by SW and AM (MW) sounds somewhat mechanical except on very strong stations.  It seems to lack body or depth on SW and AM.   Some of this undoubtedly is due to the quality of AM audio to begin with.  But the latter does sound more natural on other receivers.  The 7 bandwidths provided (1, 1.8, 2, 2.5, 3, 4, 6 kHz) do help to somewhat shape the audio, but it appears that there could be better choices for what this radio is trying to achieve.

Nonetheless on SW, the LC90 rates a comparative 3.75 on a scale of 5 for sensitivity off its built-in antenna.  That rises to a 4.0 when the external antenna described above is connected.

An unrelated anomaly was noted from using the radio on SW:  The LC90 (or at least this test unit) apparently cannot be tuned directly to frequencies in the 25 MHz (11m) band.  The radio will only accept 4 integers here, so it reverts to 120m instead of 11m.  Instead, one must press the tuning knob to change the display to 11m and then tune manually via the knob to the desired frequency.

AM (Mediumwave)

All Internet-capable radios up to now have avoided including AM – both MW and SW – into their designs due to noise and interference issues generated by the radio’s internal control signal and screen, and the difficulty involved in shielding both.

While acknowledging the considerable effort put forward by the LC90’s developers to ameliorate this problem, the radio does not fully overcome these challenges to producing “clean” AM audio.

The developers themselves seem to recognize this problem.  While they have incorporated an internal ferrite MW antenna in the radio’s design, its utility is overwhelmed by internal interference.  Rotating the radio to emphasize or null certain signals yields no apparent difference.  Consequently, the developer suggests that the listener extend the internal rod antenna for “best results”.

The AM (MW) section is unfortunately the weakest aspect of this radio.  Daytime reception is very poor – rated comparatively a 1.5 on a scale of 5.  The LC90 receives and saves through ATS only very local stations and misses several of them.

Reception does improve after dark, largely due to skywave propagation.  But it is only comparatively fair – 2.5 on a scale of 5.

Using the external clothesline antenna described above improves daytime reception to a 2.0, but those purchasing this radio should expect only marginal pedestrian – even comparatively substandard — results with AM (MW).

In sum, the audio improvements the LC90’s developers have successfully worked to provide elsewhere in the LC90 are almost undetectable here unless one is listening to an exceptionally strong AM (MW) station.

Internet Radio

To this observer, this is the core of the LC90.

There are three equally important tasks that an Internet radio must achieve to serve as a quality example for the genre:

  • Stability of signal reproduction,
  • Superior audio quality,
  • Easy user interface.

Let me begin by pointing out that it is readily apparent that the developers put lots of work into this aspect of the LC90.

The stations that do play successfully sound very good with excellent stability.  But compared to other internet radios I own and have experienced, there are just too many stations that lack that stability (characterized by frequent audio breaks or “hiccups”) or don’t load at all.

Here are some specific observations from use over several weeks:

Simply put, the user interface needs work.  While the LC90 offers several flexible tuning assists, there seem to be too many that overlap and others missing.  The effort does not seem to be centrally focused enough.  For example, listings within each category appear randomly, and many unexplainably with what looks like the same links that are indistinguishable and scattered throughout a given category.

Indeed, there are many individual listings that are repeated within the same and different lists which are found via the Tag, Menu, News. Music, Language buttons on the radio.  Why?  Is it to provide different codecs or levels of streaming quality?  There is no indication as to the way each might differ one from another, if at all.

As mentioned earlier, there is much going on here that cannot be intuitively discerned by the user/listener — and it must be!  Comparing it to other Internet radios such as the Pure Elan Connect, which uses the constantly updated Frontier Silicon station and podcast database, the LC90’s Internet radio operation is confusing and the logic behind it is difficult to perceive.

Some stations appear in Chinese and Cyrillic script, and others just as dots across a line.  This is unhelpful to listeners outside these cultures.  Also, there appear to be features within the LC90’s architecture that are “hidden”.  For example, through an inadvertent combination of key presses I found myself briefly in a listing that appeared designed solely for the Chinese market until I reset the radio by turning the radio off and then on again.

The developers appear to have created their own stations database rather than use one of the others already in use on other Internet radios.  Since it is apparently an entirely new approach, it’s impossible to determine if it is continuously updated, systematically modified or updated periodically according to some schedule.  This observer did not see any activity or change that would indicate that anything was updated over the weeks he was using the LC90.

Many domestic BBC links (Radio 3,4,5,6, e.g.) just don’t work.  When ostensibly “loading” them after selecting them, the percentage just stays at zero.  Given the importance of the BBC internationally, this is concerning and should be corrected with all deliberate speed.

In fact, this observer experienced an inordinate number of links that didn’t seem to work at all.  Some links also play initially, but then just “hang” or stop working or “hiccup” periodically (RTE, RTHK, e.g).

When comparing the LC90’s admittedly many offerings with those on Internet radios using the Frontier Silicon database, many stations appear to be missing.  However, the LC90’s developers have included in the radio’s architecture a very accessible means for the radio’s users to add stations that are not already in the radio’s database.  Whether these are just added only to the user’s radio or added globally to the LC-90 database is unknown.

In short, the way these lists — and the way the user tunes them in — work now appear to detract from rather than enhance the performance and user’s overall experience with the LC90.  This situation leads this observer to the perception that the developer’s concept(s) behind station lists and tuning is unfocused and disorganized.  This situation cannot be allowed to continue.  As stated, this user interface needs reconsideration and refinement in the opinion of this observer to make its use more intuitive for the user.

The LC90’s display for Internet radio is attractive but supplies only stream loading percentages and the station name.  There is no means of knowing the actual quality of the audio signal other than by ear.  The timer provided counting how long the station has been playing is not really of any practical use when listening to an Internet radio station.

A better use of the LC90’s screen would be to include visuals like station logos and station-provided metadata, neither of which are present now.

An anomaly that came to light through use:  The “Podcast” button only seems to provide stations like other buttons, not podcast lists.  This observer could find no way to access or listen to podcasts.  Again, this needs to be corrected.

In the opinion of this observer, the Internet section of the LC90 earns an overall 3.5 on a scale of 5 with the proviso that the radio’s audio performance with the highest quality Internet streams earns a clear 5.

Bluetooth

The LC-90’s Bluetooth feature works well.  Audio volume is jointly controlled by the source and the radio.  Its set-up and operation appear seamless.

TF and SIM cards

Not tested.  Since most SIM cards are tied to phones here, I anticipate that Internet access for the LC90 Export Version will remain with WiFi for the vast majority or, when and where WiFi is unavailable, by linking one’s phone to the radio using Bluetooth.

Neither was the timer or sleep function tested, but it can be assumed that both work as they should.

Final Notes

Other reviewers have expressed a desire for an air band, SSB capability and a fold out strip on the rear of the radio’s case so that it might be angled when used.

Frankly, I don’t see the need for any of these with the LC90 or any future enhancement or modification of it.  Anyone wishing to angle the receiver can find an inexpensive tilt stand on which to place it.  But, in that regard, I would suggest that the developer recreate the rod antenna so that it clears the perimeter of the case and allows it a full 360-degree rotation.

Otherwise, my preference would be that any such effort and the resources necessary to pursue them be concentrated on the more important matters I highlight for improvement in this analysis.

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Michael compares the Choyong LC90 Export and Chinese Versions

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


Twins, Yet Each One Unique – A Comparison of the Worldwide Version of LC90 with its Chinese Counterpart

by Michael Ye (BD4AAQ)

The export version of the LC90 is now available in the market [affiliate link]. Previously, we examined the Chinese version, which has been in the China market since early 2023. Instead of a review of the export version, this article will focus on the similarities and differences between the two LC90 versions – the version that has just started to be distributed outside China and the version that is already being sold in China. A link to my previous article can be found by clicking here.

One thing to note is the name of the manufacturer. In my previous review, I used Chaoyuan, the “pinyin” phonetic of the Chinese characters of the name of the company. As it turned out, the westernised spelling that the company uses is Choyong, or Choyong Electronics.

The LC90, a hybrid radio that combines the Internet radio with the traditional radio, is a bold move and seems to be well-received by shortwave listeners and beyond. Let’s explore what these two versions of the same model have to offer.

Appearance

The two versions of the radio look the same in appearance. However, upon closer inspection, you will notice the language on the buttons differs. The export version has all the buttons labeled in English, while the buttons of the Chinese version have a mixture of Chinese and English.

Traditional Radio

I do not find differences between the FM, MW and SW features of the two versions. Both versions have the specifications as follows: FM: 64-108 MHz, MW: 522-1710 kHz and SW: 2.3-26.10 MHz. Shortwave performance remains excellent. However, for the export version, you could toggle the MW tuning step between 9 kHz and 10 kHz, and the FM tuning step as well, through the setup (gearbox) button, but it does not seem possible to change any tuning step on the Chinese version – this seems to be a matter of software upgrade and so is not really an issue.

On both versions, press MW again to enter LW (153-279 kHz).

Internet Radio

In terms of the stations that can be heard, the Internet radio exhibits significant differences from that of the Chinese version. The Chinese version is designed to exclusively feature Chinese language stations (and a few English language stations) in China. If we were to liken the Chinese Internet radio to a closed system such as iOS, it would be stable, reliable but restrictive. In contrast, the export version could be compared to Android, offering more open, inclusive and customisable user experience.

On the export version, the MENU button provides access to the main menu, which begins with the six continents (excluding Antarctica) and allows users to navigate to the desired country and then select a specific station. Additionally, shortcut keys are available for direct access to MUSIC, PODCAST, NEWS, TAG and LANG (languages).

TAG and LANG for Ai1 and Ai2 Buttons

On the Chinese version, two buttons, Ai1 and Ai2, serve as voice assistants. Activate and speak to them and the radio directly plays the content (Ai1) or displays search results for users to choose from (Ai2). They come in handy when you look for a specific item, for instance the title of a song or a talk show. On the export version, however, the voice assistants have been removed and replaced with shortcuts TAG and LANG.

Add Your Own Stations

The Chinese version has about 1000 Chinese Internet stations built-in. On the worldwide version of the radio, there is a vast number of Internet stations available, literally tens of thousands of them, in different languages, and from different corners of the world. The number is updated from time to time. And that is not all. A really cool feature is the ability to add stations of your choice and it is easy to do with the help of a mobile phone. Unfortunately, this feature for adding your own stations is not available in the Chinese version.

Nano SIM card

The Chinese version comes with a built-in nano SIM card that is prepaid and provides Internet data. To continue using it, simply add credit to the card. In contrast, the export version does not include a prepaid, data-enabled SIM card for the user. Still, the user can use a WI-FI connection or purchase a 4G nano SIM card to insert into the device’s slot.

Some Features Not Discussed Previously

Both versions have the following features:

  • Keyboard backlight;
  • IPS LCD with backlight;
  • Type-C charging cable supplied;
  • TF card supported (to store and play your own music); and
  • Bluetooth for the radio to serve as a Bluetooth speaker.

The integration of high-tech gadgets and advanced devices into our daily routines has become indispensable in this age of the Internet. It is essential to adapt to the ever-evolving nature of the times.

Bottom Line

The Choyong LC90 is an exceptional radio that combines traditional radio features with modern Internet capabilities. It is available in both domestic and worldwide versions. The revolutionary design of the LC90 allows for excellent overall performance in both over-the-air radio reception and online streaming/podcasting.

There is no difference in traditional radio reception and performance between the domestic and worldwide versions of the LC90. However, the Internet features are drastically different, as the worldwide version serves audiences around the world, while the Chinese version is dedicated to the audience in China.

Overall, the Choyong LC90 offers a unique combination of traditional radio and modern Internet capabilities, making it a versatile and high-performing device for radio enthusiasts and music lovers.

Wish List

Is SSB decoding necessary? Well, it depends. The radio primarily caters to broadcast listeners, but both hardcore amateur radio hobbyists and general listeners may find it appealing. While adding SSB decoding can enhance its functionality, it will increase costs and may require additional space, considering it already combines two radios in one device.

There are two switches, the red button (upper right) and the volume/sleep knob (lower right side). Is it really necessary to have both?

On the export version, the “network error” message may occasionally pop up, and the radio would become quiet until human intervention steps in. Is it feasible for the radio to automatically resume play after the network error is cleared?

For some users, the antenna jack is a bit too close to the tuning knob. In most situations, this proximity does not impact the radio’s operation. However, if you need to connect an antenna using a connector, you may encounter difficulty or even find it impossible to plug it in.

Click here to check out the Choyong LC90 (export version) on Amazon.com.

Note that this Amazon link supports the SWLing Post at no cost to you. Thank you!

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Taking a look at the XHDATA D109-WB . . . a sweet spot on the price/performance curve

By Jock Elliott, KB2GOM

The XHDATA D109-WB is a small radio that hits a sweet spot on the price/performance curve, delivering a lot of performance for not a lot of money (probably less than $60 US, depending on the source).

The D109-WB measures 5.9″L x 1.45″W x 3.07″H and weighs just over 10 ounces. It covers FM 64-108MHz, AM (medium wave) 520-1710KHz, LW 153-513KHz(9K), SW 1711-29999KHz, and seven NOAA Weather Radio channels 162.40-162.55MHz with alert function. It does not receive single-sideband signals. It offers 100 FM memories, 100 LW memories, 100 MW memories, and 300 SW memories. Further, it offers 1, 2, 3, 4, and 6 kHz bandwidths on MW and SW bands.

On the left side of the front panel is a plastic grill that fronts an inch-and-a-half speaker. On the right side is a small LCD screen with backlight that functions as information central for the D109-WB. Below it are 15 buttons (3 rows of 5 buttons each) that control various functions, including an “SOS Emergency Distress Sound and Light Alarm,” manual tuning and various auto scanning and auto memory storage schemes, band selection, DX/local receive mode selection, 9/10 kH MW spacing, clock alarms, bandwidth selection, a key lock/display switch, and a manual tune/memory mode switch, among others. Below those 15 buttons is a 3 x 4 numerical key pad for memory and direct frequency entry functions. To the right of the keypad are 5 buttons set in a circular pattern for controlling Bluetooth use and connectivity and MP3  playback (I did not test these last two functions).

On the right side of the case, you will find a type-C socket for plugging in a cable to charge the 18650 battery, a wheel for volume control, and a tuning knob.

On the left side of the case are 3.5 mm headphone and external antenna jacks.

On the back panel is a flip-out support and a hatch for accessing the battery. On the top, there is a fold-over 21-inch telescoping antenna and, on the bottom, two anti-skid rubber feet.

In all, I found the D109-WB to be solidly constructed with fit and finish appropriate to a radio in its price class. The only serious deficit I found in the D109-WB was the extremely small type in the owner’s manual. Consult the photograph below to see what I mean.

The D109-WB was straightforward to operate, and I enjoyed it. One cute trick was variable-speed tuning: on MW, turn the knob slowly, and it will change frequency in 1 kHz increments. Turn the knob fast, and the tuning rate jumps to 10 kHz increments (or 9 kHz, if you have selected that tuning option). Variable-speed tuning works the same way on the shortwave bands, and on the FM band, the slow tuning rate is .01 MHz, and it jumps to .1 MHz when the knob is turned quickly. I had not experienced variable-speed tuning in any other radio, and I like it . . . a lot.

But what I was really wanted to know was how well did the D109-WB perform?

Now here’s the rub: I don’t have any test equipment . . . but I do own a CCrane Skywave 2. So I sat down on a bright sunny afternoon with the D109-WB and the Skywave 2 side-by-side and compared them. I found that both would receive two weather channels loud and clear and one more weather channel marginally. Then I tuned firm the medium wave band, then the FM band, running the two radios in parallel and found that there was nothing that I could hear on Skywave 2 that I could not also hear on the D109-WB, and vice versa. In other words, I found the electrical performance of the two radios to be very similar . . . except, of course, that the Skywave receives the AIR band, and the D109-WB does not.

One of the things that I enjoy doing is to grab a radio, select a band, punch the SCAN button, and see what’s out there. Since I also own a Tecsun PL-880, I decided to run a scan on each band on each radio (D109-WB, Skywave 2, and PL-880) with its native whip antenna and see how many detectable signals I could find on each. By “signal,” I mean any place where the scan stopped where I could hear music, voices, or anything that sounded like a transmitted signal, as opposed to pure noise.

So here are the results of two different testing sessions on two different nights:

D109-WB vs. CCrane Skywave

D109-WB vs. Tecsun PL-880

A caution: before you start drawing conclusions from the results above about which radio is more sensitive than another, it is important to consider that those results may be heavily skewed by whatever “SCAN” algorithm is programmed into each radio. Further, the parameters of the SCAN algorithm for a particular radio are a black box to those who use the radio. What I can conclude from those results is that, if you want to be a lazy DXer like me and use the SCAN button for cruising the bands, the D109-WB will deliver pleasing results.

Since the D109-WB has a socket for plugging in an external antenna, I plugged in a 45-foot loop antenna. The D109-WB overloaded, but when I set the DX/local switch to local, the overloading went away but there was still a boost in signal-to-noise from the external antenna.

So, the bottom line: the XHDATA D109-WB delivers a whole lot of fun and performance at a very reasonable price, and I can easily recommend it for both newbies and old-timers alike.

In fact, if you want to turn a kid onto radio, here’s an idea: give the child a D109-WB and a paper atlas, explain how both work, then set that kid to work logging as many stations as possible and looking up where they are located. Heck, that sounds like fun to me.

Click here to check out the XHDATA D109-WB on Amazon.com

(note: this affiliate link supports the SWLing Post at no cost to you)

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