Category Archives: Mediumwave

Video Presentation: WLW Radio -100 Years – Behind The Scenes by Dave Snyder

A view of the iconic WLW tower taken from the neighboring VOA Bethany site and museum.

Many thanks to SWLing Post contributor, David Snyder, who shares this presentation outlining the history of WLW for the National VOA Museum of Broadcasting YouTube channel.

Video description:

Behind the scenes pictures from the efforts of Powel Crosley, Jr. creating the famous WLW Radio Station, including the largest USA AM broadcast transmitter at 500,000 watts.

Click here to view on YouTube.

Most excellent! Thank you for sharing this, David.

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Ukraine: BBC adds two shortwave broadcasts, NEXUS adds MW service

Many thanks to SWLing Post contributor, Andrea Borgnino (@aborgnino), who notes:

On shortwave, the BBC is adding 2 shortwave broadcasts to Ukraine on 5875 kHz from 8/10 UTC and on 15735 kHz from 2/4 UTC.

On medium wave, NEXUS- of Milan in Italy on 1323 kHz and proposes broadcasting for Eastern countries from 7/11 p.m. CET

Thank you for sharing this, Andrea.

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International Radio Club’s Reprints collection of 900+ articles

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

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

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

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

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

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Guest Post: Calculate Station Distances Using Excel Formulas

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


Calculate Station Distances Using Excel

By Bob Colegrove

Introduction

On occasion, I’ve wanted to know just how far away a station was from my home.  I’ve never been much of a contester, but I know distance can play a part in the results.  There are a number of Internet cites which let you enter latitude and longitude information and then calculate the distance across the surface of the earth.  These are alright on an occasional basis, but I often wind up getting the data mixed for the two locations, and it is not handy when you want to make several measurements.  Here’s a way to generate the distance from your home to thousands of stations with just a little effort.

Many years ago, armed with my faded knowledge of high school trigonometry, I used Excel to calculate the surface distance between any two points on earth.  I managed to find the spreadsheet (file dated 1998) which has no fewer than 11 steps in the algorithm.  Although it worked, when I came back to it a few months later to make a change, I couldn’t remember my thought process.  There are Internet sites which develop earth surface calculations in highly esoteric terms and heavy-duty math.  But life is short, and I wanted to cut to the chase.  There are, in fact, several formula variations which have somehow managed to distill all this down to a neat single-cell calculation, and they seem to work very well.

Construction

The spreadsheet figure below is the simplest form used when you have decimal latitude and longitude data as input.  The convention is to use negative numbers for the Western and Southern Hemispheres.  Home is your reception location and all other locations are compared with that to determine the distances.  If you’re curious, the home location (yellow cells) used in these examples is the monument marking the geographic center of all 50 US states in Belle Fourche, South Dakota.  Google Maps is one easy source to determine the exact latitude and longitude of any point on earth.

To calculate the distance between any two points on earth, copy the formula below directly into a cell, then change the reference cell names as appropriate, and you’re ready to go.

=ACOS(COS(RADIANS(90-$B$5)) * COS(RADIANS(90-B9)) + SIN(RADIANS(90-$B$5)) * SIN(RADIANS(90-B9)) * COS(RADIANS($C$5-C9))) * 3959

$B$5 and $C$5 are the cell references for your home address (yellow in the figure above).  Of course, the dollar signs indicate these data remain fixed in each calculation.  B9 and C9 are corresponding latitude and longitude for the example radio station, WTOP (green).  Change these four cell locations as necessary.  The constant, 3959, at the end of the formula is the average radius of the earth in miles.  Use 6371 if you want kilometers.  The data cells in Columns D and E are populated with the formula and produce the result. These values are dynamic and can be replicated down the columns for the rest of your station location data.

Degrees, Minutes, and Seconds Format

The US FCC on-line database contains latitude and longitude tower locations for medium wave stations in Region 2, North, South, and Central America.  However, coordinates are in degrees, minutes, and seconds format and must be converted to digital format for calculation of distances.  The conversion process can also be done in Excel.

In this case, the inclusion of the coordinate hemispheres, N or S, and E or W is important.  Whereas, the hemispheres in the decimal example were signed + or -, the inclusion of the appropriate letters here is necessary.  Cell L5 reads

=IF(H5=”S”,-I5-(J5/60)-(K5/3600),I5+(J5/60)+(K5/3600))

and cell Q5 is similar for longitude, except “W” is substituted for “S.”  These formulas are then replicated in columns L and Q for each data item.  Columns R and S contain the distance calculation formulas as described above.  Line 14 is not necessary, but can be used to see if your formulas are correct; that is, the distance from home to home should be zero.

Let Excel Get the Information for You

What follows is for anyone tired of copying cumbersome latitude and longitude data.  Unfortunately, it only works on the current version of Microsoft 365 Excel, and apparently goes off into the big cloud in the sky to instantly download the information.

  1. Enter the town followed by either the US state, Canadian province, or other country name (Column A).
  2. Copy these locations to the next column (Column B).  The cells in Column B will become temporary geography cells.  Note:  As shown above, the data have already been converted to geography format (Step 4).
  3. Make sure you have all the geography cell locations selected (Column B).
  4. On the Data ribbon select Geography.  A map icon will appear at the left of each cell, and the state, province and country will be truncated.
  5. For the first latitude (Cell C7), enter =B7.Latitude; likewise, =B7.Longitude in Cell D7.
  6. The formulas in C7 and D7 can be replicated down your list.
  7. Columns for miles and kilometers (E and F) can be added using the distance formula as described above.

The geography data (Column B) cannot be replicated.  If you want to add data later, you will have to reapply the geography format for the new data.  Or, latitude and longitude can still be inserted manually for any additional entries.  The geography data (Column B) are not needed beyond this point and can be deleted or hidden.

Note:  I logged on to my first mainframe computer in September 1976 and have never ceased to be amazed at what these confounded things can be made to do.  I tried as best I could to trip the system with small, obscure towns in faraway places, as well as duplicate names.  I finally succeeded with a relatively large city, Ulaanbaatar, Mongolia.  To be fair, I tried to get it to accept alternate spellings.  So, if you need that one, you’ll have to enter it manually.

Medium Wave Example

This example is for medium wave DXers in Region 2, the Americas.  It makes use of the FCC AM database at https://www.fcc.gov/media/radio/am-query.  The database currently contains more than 24,500 entries, many of these are duplicate entries for stations using different daytime and nighttime powers.

  1. Download the database as a pipe-delimited text file.
  2. Import the file into Excel.
  3. Create additional columns to convert the latitude and longitude data from degree-minute-second format to decimal as described above.
  4. Add some rows above and enter your home coordinates in decimal.
  5. Create another column to calculate the distance from home to all the stations, again using the base formula above.
  6. Hide any columns in the FCC database that you don’t need.
  7. Finally, by creating an Excel table from all of the data, except your home location, you can do some on-the-fly filtering.

The example below shows some of the stations near our example home in Belle Fourche, South Dakota.  The Distance column on the right has a filter applied to limit the listing in the table to stations within a 150 mile radius, that is, it only lists potential daytime stations.  You could also use the conditional formatting feature of Excel to highlight the same information in the unfiltered data.

Shortwave Example

The AOKI log, http://www1.s2.starcat.ne.jp/ndxc/, has listings for all of the recent broadcasting cycles, B21, A21, etc.  The Excel format files are zipped for download, and include the latitude and longitude of each station.  Unfortunately the coordinates are not only in degrees, minutes and seconds, but they are all mashed together in one cell for each listing.  Excel to the rescue again.  Select Text to Columns in the Data Tools portion of the Data ribbon.  This feature will allow you to divide the single column into four columns each for latitude and longitude, that is, degrees, minutes, seconds and hemisphere.  Then you can use the conversion formula to change degrees-minutes-seconds to decimal.  Note that the first three digits used for longitude are minutes (they go up to 180); the remaining numerical columns have two digits each (up to 60 or 90), and the hemisphere columns (alpha) one character each.

Accuracy

Here are a few things affecting accuracy:

  1. The constants 3959 or 6371 used in the formula for miles and kilometers are generally accepted averages for the earth’s radius.  The difference between the equatorial (longer) and polar (shorter) radii is about 13 miles.
  2. If you are using town locations in your data, remember that the actual distance to the tower in that town is likely to be different.  The FCC and AOKI data are assumed to be station tower locations.
  3. Some decimal sources of latitude and longitude data have less resolution, which could lead to a slight error.

You’re on Your Own

You may have noticed the examples shown in the figures all have multiple station locations. My thought in doing this was provide some test for accuracy and secondly to provide a seed for developing the spreadsheet into a more inclusive log of stations. There is likely enough basic Excel knowledge among the folks gathered here, and each person will likely have an individual preference in designing a spreadsheet. Nevertheless, the spreadsheet shown in the figures can be downloaded by clicking this link.

The first sheet shows Figures 1 and 2 from this article; and the second sheet, Figure 3. The link in Cell I2 of the second sheet describes how to use the geography feature of Microsoft 365 Excel. The third sheet is a recent copy of the FCC AM database (Figure 4). To facilitate storage and downloading, only stations from 530 kHz to 600 kHz are included. Numerous unused columns from the FCC AM database have been hidden; so you can still copy the full, pipe-delimited FCC database into Columns A through AH. The FCC database has been converted to an Excel table; the Home location is not part of the table. Try substituting your own location for Home (Cells AI2, latitude and AJ2, longitude) and setting a distance filter from your home in Cell AK4. In the example, the distance filter has been set limiting the list of stations to less than 600 miles from our example in South Dakota. Note also that the Conditional Formatting feature on the Home ribbon has been used to highlight stations less than 100 miles from home.

If you have any interest in developing your own spreadsheet, perhaps you can comment on what you have done, or provide the rest of us with something I have missed. Hopefully, I have provided enough information to get you started.

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DX Central’s MW Frequency Challenge: Week 11 Results and Week 12 Announcement

Many thanks to SWLing Post contributor Loyd Van Horn at DX Central who shares the following announcement:


Another great week of DX and another productive one for us at DX Central and for many DXers, according to the logs!  We spent the week diving back into another graveyard frequency (1490) and the results speak for themselves!

As a reminder, our live streams on Sunday nights have been so much fun getting to interact and hear about what you heard in the previous week.  If you haven’t been able to make it to a livestream yet, you are missing out!  Join us Sundays at 1945 CST / 0145 UTC (Monday morning, UTC) on our YouTube channel:  youtube.com/c/dxcentral

A total of 22 DXers from three countries (Mexico, Canada and the US) and 18 US States brought in 127 logs for Week 11 of our MW Frequency Challenge.    76 unique stations in 34 U.S. states and three countries made it to this week’s log. Continue reading

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Celebrating World Radio Day 2022!

Today is UNESCO World Radio Day and this year the theme of trust highlights the importance of radio as an accessible form of information.

Below are some of the many projects celebrating World Radio Day:


Cities and Memory: Shortwave Transmissions

As mentioned in a previous post, we at the Shortwave Radio Audio Archive are truly honored to have been a resource for this incredible and diverse sound project organized by Cities and Memory.

We encourage you to explore the creative work from over 120 artists and composers.

A great many of these remarkable dynamic works draw on a wide array of recordings from the SRAA; the resulting compositions and soundscapes are rich with sonic textures, evocative collages of sound and memory, which emerge into further sources of inspiration.

Our profound thanks to Cities and Memory––and all of the participating artists––for this truly brilliant collection which you can check out on the Shortwave Transmissions project page.


BBC World Service Documentary: “World Wide Waves ’22: The sounds of community radio”

As we mention in a previous post, this brilliant radio documentary focusing on community radio is available on the BBC World Service website and BBC Sounds

Here’s the description:

For World Radio Day 2022, we tune in to radio stations around the world that connect communities, spark conversations, keep traditions alive and give a voice to their listeners. From Aboriginal Koori Radio in Australia to a community station in India run by rural women from the lowest Dalit caste, the airwaves carry intimate wisdom, vital knowledge, beats and tunes that keep reminding us who we are.

Note that this piece was produced by our friend David Goren, of Shortwaveology fame. Continue reading

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Radio Waves: Mazdas Stuck On KUOW, Golden Age of Radio, Russian SW Broadcasts to Arctic, FCC Cleans Up Rules, and Starlink Loses 40 Satellites to Geo Storm

Radio Waves:  Stories Making Waves in the World of Radio

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

Much thanks to the many contributors who shared the following items:


You’re listening to KUOW … like it or not: Mysterious glitch has Mazda drivers stuck on public radio (Geekwire)

Drivers of certain vehicles in Seattle and other parts of Western Washington are shouting at their car radios this week. Not because of any particular song or news item that’s being broadcast, but because an apparent technical glitch has caused the radios to be stuck on public radio station KUOW.

The impacted drivers appear to all be owners of Mazda vehicles from between 2014 and 2017. In some cases the in-car infotainment systems have stopped working altogether, derailing the ability to listen to the radio at all or use Bluetooth phone connections, GPS, the rear camera and more.

According to Mazda drivers who spoke with GeekWire, and others in a Reddit thread discussing the dilemma, everyone who has had an issue was listening to KUOW 94.9 in recent weeks when the car systems went haywire.

KUOW sounded unsure of a possible cause; at least one dealership service department blamed 5G; and Mazda told GeekWire in an official. [Continue reading…]

The real reason the 1930s were considered ‘the golden age of radio’ (The Grunge)

While it’s been widely contested who actually invented the first radio (both Italian physicist Gugliemo Marconi and Serbian-American inventor and engineer Nikola Tesla were fighting for the first patent, per PBS), it was Marconi who came out top in 1904, when the U.S. Patent Office officially dubbed him the inventor of the new breakthrough technology. According to APM Reports, in 1920, Americans had their first commercially licensed radio station in Pittsburgh, Pennsylvania: KDKA. That number quickly rose after KDKA broadcast the election that saw Warren G. Harding become the 29th president, and by 1924, 500 stations were available for listening.

By 1930, over “40% of American households owned a radio,” per APM Reports. This became known as “The Golden Age of Radio.” As revealed by PBS, in 1930, 12 million Americans owned radios — growing to a whopping 28 million by the end of the decade.

Access to the radio came at a turbulent time in history. As the Great Depression caused widespread suffering for millions of Americans (via History), the households that could afford a radio saw it as a welcome source of entertainment and news that made them feel connected to the rest of the country. These days, with over 15,445 radio stations available in the U.S., it’s clear the radio still remains relevant, but its impact on society truly began nine decades ago. Let’s take a look at the real reason the 1930s were considered “The Golden Age of Radio.” [Continue reading…]

Russia initiates cross-border radio broadcast in North’s languages (Russian News Agency – TASS)

ST. PETERSBURG, February 7. /TASS/. The International Consortium for the Preservation of Arctic Cultural Heritage, based at the Russian State Hydrometeorology University (RSHU), initiated a cross-border radio broadcast in languages of the North’s indigenous peoples, the university’s representative in Moscow Andrei Bryksenkov told TASS.

An application for the broadcast has been filed with the Arctic Council. “The application must be filed from two countries, and we plan to go along with Norway – with the Sami Radio, which is a part of Norway’s big television and radio concern. <…> The idea has been supported at all levels. As for the cross-border broadcast, we, probably, will begin from the shortwave broadcast, as it covers bigger territories and is less costly,” he said.

At the initial stage, the pilot broadcast will be organized on the territories of Finland, Norway and Russia. The project’s initiators are ready to cooperate with other countries. “One transmitter in Krasnoyarsk may cover 80% of the Russian North. Norway has such a transmitter, which covers the Scandinavian territory. Another two transmitters are on Alaska,” he continued. Later on, the broadcast will be also on middle and long waves, thus one frequency will carry 3-4 channels, he added. One of them will be in Russian and English, and the rest – in languages of the indigenous peoples.

The audience will learn about traditions, skills of the peoples living in the North. The content will fully focus on culture. The countries, participating in the project, will open newsrooms. “We hope the general center, which will coordinate the project, will be at the Arctic Council,” he said.

The International Consortium for the Preservation of Arctic Cultural Heritage includes St. Petersburg’s committee on the Arctic, the Arctic museum and exhibition center in St. Petersburg, the Association of indigenous low-numbered peoples of the North, Siberia and Far East, and others. [Read full article…]

FCC Is ‘Cleaning Up’ Of More Radio Rules. Here Is What Will (And Will Not) Change. (Inside Radio)

The modernization of radio’s regulatory rulebook that began under the prior administration continues at the Federal Communications Commission. It is slated to approve a half dozen changes at the Commission’s February meeting, in what Chair Jessica Rosenworcel says is a “cleaning up” of the broadcast radio rules.

“The Commission’s current rules for full-power and translator radio stations contain a number of provisions that are redundant, outdated, or in conflict with other rules,” said Rosenworcel. She said the proposal would “update and clean up” those provisions “in order to reduce any potential confusion, alleviate unnecessary burdens, and make sure our rules reflect the latest technical requirements.”

The proposed order (MB Docket No. 21-263) would update six rules, while scrap plans to change another. They include –

Eliminate Transmitter Power Limit Rule For AMs.

The draft order says the FCC has tentatively concluded the rule is “outdated and unnecessary” given its current reliance on actual operating antenna input power as the most accurate and effective means of ensuring that AM stations adhere to their authorized power limits. The FCC also agreed with comments filed by the National Association of Broadcasters that said the elimination of the technical restriction will allow AMs of any class to use transmitters of any rated power. That, it says, will benefit all AMs by broadening the market of transmitters, enhancing the secondary market for AM transmitters, and reducing the number of transmitters that need to be disposed of.

Clarify AM Fill-in Area Definition

The FCC is poised to amend the definition of an “AM fill-in area” used when an FM translator simulcasts an AM station. [Continue reading…]

Geomagnetic storm and recently deployed Starlink satellites (SpaceX Blog)

On Thursday, February 3 at 1:13 p.m. EST, Falcon 9 launched 49 Starlink satellites to low Earth orbit from Launch Complex 39A (LC-39A) at Kennedy Space Center in Florida. Falcon 9’s second stage deployed the satellites into their intended orbit, with a perigee of approximately 210 kilometers above Earth, and each satellite achieved controlled flight.

SpaceX deploys its satellites into these lower orbits so that in the very rare case any satellite does not pass initial system checkouts it will quickly be deorbited by atmospheric drag. While the low deployment altitude requires more capable satellites at a considerable cost to us, it’s the right thing to do to maintain a sustainable space environment.

Unfortunately, the satellites deployed on Thursday were significantly impacted by a geomagnetic storm on Friday. These storms cause the atmosphere to warm and atmospheric density at our low deployment altitudes to increase. In fact, onboard GPS suggests the escalation speed and severity of the storm caused atmospheric drag to increase up to 50 percent higher than during previous launches. The Starlink team commanded the satellites into a safe-mode where they would fly edge-on (like a sheet of paper) to minimize drag—to effectively “take cover from the storm”—and continued to work closely with the Space Force’s 18th Space Control Squadron and LeoLabs to provide updates on the satellites based on ground radars.

Preliminary analysis show the increased drag at the low altitudes prevented the satellites from leaving safe-mode to begin orbit raising maneuvers, and up to 40 of the satellites will reenter or already have reentered the Earth’s atmosphere. The deorbiting satellites pose zero collision risk with other satellites and by design demise upon atmospheric reentry—meaning no orbital debris is created and no satellite parts hit the ground. This unique situation demonstrates the great lengths the Starlink team has gone to ensure the system is on the leading edge of on-orbit debris mitigation. [Read at SpaceX…]


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