Tag Archives: Mediumwave

Simple Wire Antenna: Giuseppe’s Mediumwave DXing Adventures from the Tyrrhenian Sea

18 Replies

Many thanks to SWLing Post contributor, Giuseppe Morlè (IZ0GZW), who writes:

Dear Thomas and Friends of SWLing Post,

I am Giuseppe Morlè from Formia, Central Italy, on the Tyrrhenian Sea.

This time, I want to share a very simple antenna setup for listening to and attempting extreme DX on Medium Waves.

I first saw this antenna in several videos, and many DXers have used it during various expeditions.

For my setup, I used a 15-meter-long wire. At around 11 meters, I formed a small coil with 8 turns, then continued the wire for another 3 meters.

I began with some tests on my balcony by laying the wire flat along the ground for its entire length. I used my small Sony SRF-37V as a receiver. By placing the receiver within the coil of turns, I immediately noticed a significant difference compared to the built-in ferrite antenna.

In the early afternoon, I tuned into a Chinese language broadcast on 1377 kHz. You can watch a video of this experiment on my YouTube channel:

Encouraged by the excellent results, I decided to head to the tourist port of Caposele di Formia the next day in the early afternoon. I set up on the pier overlooking the sea. This time, I laid the wire in an eastward direction — towards the night, where the sun had already set, while it was still high for another two hours on my side.

Once again, I achieved amazing results.

I was able to hear the same Chinese station on 1377 kHz, but this time with much clearer audio than from my balcony, where electrical noise interfered. By the sea, the signal was clean and strong.

After a while, I tuned into VOA broadcasts from Thailand on 1575 and 1395 kHz, both with surprisingly good audio quality. You can see this second experiment here:

Sometimes, all it takes is a bit of wire and a small coil to create an excellent, ground-level antenna — in this case, oriented eastward.

I also tried using my loop cassette and a Tecsun PL-660 but couldn’t hear anything. Yet the little Sony SRF-37V proved itself to be a true “DX killer” on AM — truly impressive.

I even caught a segment of the VOA program “World Today,” discussing the Chinese economy and Southeast Asia.

As the sun set, the DX signals faded, making way for closer European and Asian broadcasters.

I will definitely return with a longer wire to see if this surprising setup can be improved even more.

A warm greeting to all the Friends who follow SWLing Post and to you, Dear Thomas.

73, Giuseppe IZ0GZW

More Reception Videos:

Bob’s Radio Corner: Pairing a Phone or Tablet with a Radio

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Pairing a Phone or Tablet with a Radio

By Bob Colegrove

The Internet is full of resources for radio listeners and hobbyists.  There are numerous examples of general information, frequency, and schedule lists.  There are also WebSDR sites, which allow you to compare reception experiences from around the world.  All of these can be accessed quickly and easily by having them loaded on your phone or tablet operating side-by-side with your radio and having Wi-Fi or cellular access.  We never had any of this when I was starting out.

I realize there are other ways to go about what I have described below, for example, merging station listings with SDR.  This posting is for folks like me who are SDR-challenged.  I listen to plain old radios.  My modern-day experience with newfangled technology has been limited to hitchhiking on WebSDR sites for the last few years.  It has served me well.

Ideally, I would like to generalize this topic to simply cover all phones and tablets.  In truth, my experience has been limited to an iPhone and Kindle Fire tablets.  They have worked very well as I shall explain.  Perhaps you have paired a different phone or tablet with your radio, in which case, feel free to share your experience.

The choice of a phone or tablet is yours.  Either works well.  Your decision will be affected by what you have available and what is easier to use.  If you intend to buy a new device and associate it with your radio, cost will be an additional factor.

A noteworthy device (the one I tend to favor) is a Kindle Fire.  Mainly, they are cheap.  The regular price of a 7-inch model is just under $60 and can often be purchased for less during Black Friday and Prime Day sales.  It is versatile, possessing all the usual functions except for cellular access.  Perhaps most importantly, it is virtually noise-free.  For a while I struggled using Internet sources on a laptop computer.  Even a good one located about 10 feet away from the radio antenna generates noise.  On the other hand, I have taken a 7-inch Kindle Fire in hand and placed it against the resonant coil of a loop antenna.  This abuse generated no more disturbance to the antenna than if it were a block of pinewood.  I have noticed some slight noise from the 11” Kindle when the antenna is exposed this way, but when that tablet is held at arm’s length from the antenna, all is well.  Recently, I have expanded this application to my iPhone and found its noise immunity matches that of the Kindle Fire 7.

Broadcast Schedules

The most useful Internet resources are the broadcast schedules.  These are the comprehensive frequency-time-station listings that tell us where and when to tune.  There are many good ones.  My favorites are the EiBi listing http://www.eibispace.de/, and Dan Ferguson’s https://groups.io/g/swskeds/topics.  For the latter you will need to request membership.  SWskeds merges EiBi, Aoki (https://www1.s2.starcat.ne.jp/ndxc), HFCC (https://new.hfcc.org/index.php), as well as other sources into a single list.

Processing

The EiBi listing comes as a CSV-formatted text file, which can be imported into a spreadsheet. I have done some processing using spreadsheet functions to produce a customized listing.  Processing the frequency-time-station lists is most conveniently done using a computer rather than the phone or tablet.   Processing includes selecting, arranging, or filtering the downloaded data tailored to your needs.  This might include adding a filterable column to indicate only stations that are on at the current time.  Some users might favor filtering by country or station. The heavy lifting processing is done automatically whenever a new listing is published by simply dropping the new file into the existing spreadsheet.  No, the functionality of a spreadsheet and ease of editing are not as good on a tablet as with the mouse and keyboard of a computer.  My processing on the computer includes measures to optimized the screen view to the most essential information thus minimizing the amount of scrolling on the tablet.

After the files are downloaded and processed, they can be loaded on the phone or tablet in a couple of different ways.  They can be directly transferred over a USB cable, or they can be transferred using a cloud server.  The USB cable-transfer method may be difficult on some devices, particularly iPhones.  The Kindle seems to be the more convenient device.  Being an obedient Microsoft customer, I can also transfer the files from my computer to OneDrive, then pick them up on the Kindle or iPhone using the OneDrive and Microsoft 365 apps which are available for both phone and tablet.

Examples

The screenshot below shows an EiBi example at 0014 UTC.  Although the “ON” column filter is set to show only transmissions currently “ON,” it had not been manually updated on the Kindle for a couple hours and thus includes listings from a previous time.  The EiBi database does not include transmitter power or beam information.  However, the identification of countries and transmitter sites is extensive.  These are determined by downloading and printing the README.TXT file on the EiBi site.

The SWSkeds listing is available in both CSV and Excel formats.  It contains several additional data fields, very importantly including transmitter power and beam direction when available.  For this list, I make the simple conversion of the existing Excel data range tab, “COMBINED” to a table so I can easily apply filters.  The screenshot below shows an example at 1750 UTC with the “ON” column filtered to “ON.”

Not to be left out, the complete medium wave broadcast station list for Region 2, the Americas, is easily downloadable at https://www.fcc.gov/media/radio/am-query.  The entire database is formidable and contains nearly 600 pages in a printable format.  Much of this bulk is due to the doubled size necessitated by giving both daytime and nighttime power separate entries for each station.  A number of marginally useful data columns can be eliminated in spreadsheet processing.  I have added formulas to calculate the azimuth heading and distance from my listening post (blanked out in the example below).

A variation of the downloadable file format is the direct-query site, SHORT.WAVE.INFO.  Here you can simply enter queries by station, language, frequency, or band, and produce listings which match your criteria.  Any listings which are currently on the air will be highlighted in red.

WebSDR

Finally, I would like to mention the WebSDR sites.  While not used explicitly for broadcast schedules, these sites are great for anyone wanting to compare how well they are receiving signals relative to what others are experiencing.  Granted, location and time of day are big factors that affect reception, but it is still useful to make these relative comparisons.

Home base is http://websdr.org/ which presents a catalog of many WebSDR sites by location.  At the bottom of the page is a world map which pinpoints the location of each site.  Most of these sites cater exclusively to hams; however, The University of Twente, Enschede, Netherlands (http://websdr.ewi.utwente.nl:8901/) covers 0.000 to 29.160 MHz unabridged.  The screenshot below shows the tablet/phone version of the U. of Twente site.  There are also two sites on the US East Coast which cover some non-hamband portions of the SW spectrum:  http://na5b.com:8901/ in the Washington, DC area and http://websdr.k3fef.com:8901/ in Milford, Pennsylvania.  The SHORT.WAVE.INFO and WebSDR sites can be directly accessed and queried over the tablet’s browser and a Wi-Fi or cellular connection.

Using the System

In my relentless pursuit to log the Nibi-Nibi Islands, I will load up one of the frequency-time-station listings and start my DX session.  This typically includes a scan of a particular band, checking signals I can receive against the lists.  If my interest peaks on a particular catch (usually a weak one), I will switch the tablet over to a WebSDR site to see how it is being received in Europe or along the East Coast of NA.

In summary, ready access to these Internet resources using a phone or tablet next to the radio has notable advantages:

  • The frequency-time-station listings provide quick, reliable signal identification in most cases.
  • The WebSDR sites confirm that my antennas are doing their job.

Am I done?  I hesitate to stop here.  The process of discovery is a marvelous human experience.  The foregoing are merely starting points.  Other applications might include sunrise-sunset calendars or maps or propagation forecasts.  There are certainly other ways to do all this depending on your druthers.  I know I am erring by omission and neglecting many other good resources.  Let’s hear about yours.

From NDBs to TIS: A DXer’s Journey Across 1610-1700 kHz

4 Replies

Many thanks to SWLing Post contributor Dan Greenall, who shares the following guest post and asks, “Wonder who can add to this list?“:

A Look Back – DXing between 1610 and 1700 kHz

by Dan Greenall

1. The Caribbean Beacon, Anguilla West Indies 1610 kHz (1985 QSL)

2. NDB stations (non-directional beacons)

  • transmitted call letters on CW, mostly from airports, heard in the 1970’s
  • examples: MDE Medellin, Colombia 1690 kHz and RAB Rabinal, Guatemala 1613 kHz

3. U.S. Army Broadcasting Service KTRK 1670 Fort Meade, MD Feb 1996          articles and recordings

https://www.radioheritage.com/ktrk-k-truck-1670-khz/

4. FCC Part 15 Radio Stations

Example:    WDKW 1630 “the Klaw” Dundalk High School near Baltimore, MD

Audio Player

Link to my recording made at a DX camp in Coe Hill, Ontario, Canada on April 20, 1997: https://archive.org/details/wdkw-the-klaw-1630

An internet search revealed the following;

Part 15 of the Federal Communications Commission (FCC) rules allows some low-powered radio devices to operate without a license on the AM and FM radio broadcast bands. These devices are subject to certain restrictions, including:

  • Range: On FM frequencies, the effective service range is limited to about 200 feet (61 meters).
  • Field strength: The field strength should not exceed 250 ?V/m (48db) at 3 meters.
  • Detachable antennas: Part 15 rules prohibit detachable antennas on all Part 15 transmitters.

Some examples of Part 15 radio stations include:

  • Microbroadcasting

Often used by hobbyists, drive-in theaters, or on college or high school campuses.

  • Talking roadsigns, talking houses, or talking billboards

These transmitters air a repeating loop of information, such as traffic or highway construction. They typically operate on empty channels on the AM broadcast band.

  • InfOspot

A custom product that can include special audio systems, USB / internet connectivity, cabinets, and antenna mounting styles.

  • Free-radiate AM radio stations

Educational institutions can use a transmitter without a license if the signal coverage is limited to their property.

5. TIS (Travellers Information Stations)

1610 kHz with low power, usually around 10 watts, such as the one I hear near the Blue Water Bridge between Sarnia, Ontario and Port Huron, Michigan

6. Expanded AM broadcast band 

Over a quarter century ago, these frequencies began to be used in the U.S. by BCB stations.  I still have recordings of a half dozen of these from the early days.

WTDY 1670:

Audio Player

WNML 1670:

Audio Player

WMDM 1690:

Audio Player

KCNZ 1650:

Audio Player

KCJJ 1630:

Audio Player

KBGG 1700:

Audio Player

Also, here is a link to a column in Popular Communications magazine from February 1998.

https://www.worldradiohistory.com/Archive-Popular-Communications/90s/Popular-Communications-1998-02.pdf

Pavel’s Practical Electronics Homebrew Mediumwave Ferrite Antenna

2 Replies

Many thanks to SWLing Post contributor, Pavel Kraus, who shares the following guest post:

Mediumwave Ferrite Antenna

by Pavel Kraus

This antenna for MW was made according to the instructions from Everyday Practical Electronics magazine, September 2000. The author of the Active Ferrite Loop Aerial construction project is Raymond Haigh.

The antenna was only adjusted mechanically according to my capabilities. Reception on this antenna was tested with receivers Malahite DSP 2 – original, Belka, Qodosen DX 286, AOR 7030+, Eton E1 XM and other receivers. Of course, the antenna does not replace a long wire antenna, but in limited urban conditions its performance is sufficient. I compared the antenna to Garry Thomas’ factory Quantum Loop.

Both antennas work similarly, Quantum Loop has a shielded ferrite rod, it is less susceptible to elmg. interference. Raymond Haigh’s antenna shows a bit more gain, the ferrite antenna is made up of 7 pieces of ferrite rods 20 cm long and 1 cm in diameter. The antenna is not shielded.

The construction of the antenna according to the instructions is not difficult. A Raimond Haigh antenna will definitely improve MW reception, especially for radios without an internal ferrite antenna. Instructions can be found at https://www.worldradiohistory.com/UK/Practical-Electronics/00s/Everyday-Practical-Electronics-2000-09.pdf

Belka Test

https://www.youtube.com/watch?v=Yk-ngCQ8TFc

Qodosen DX286 Test

https://www.youtube.com/watch?v=F77HOJSmu_4

Malahite DSP2 Test

https://www.youtube.com/watch?v=C2dvaCT9z6Y

Responding to “The Colegrove Inspiration”

16 Replies

By Jock Elliott, KB2GOM

It was Bob Colegrove’s post — this one — that inspired me and set me on this path.

Medium wave broadcast band DXing (MWBCB) has a certain fascination for me, but I am poor at it. Oh sure, I have read the advice: map the band at noon, then again at midnight, and you’ll have a better idea of what’s unusual as you are tuning around. But I have never gotten around to doing the mapping, so my DXing skills are lousy at best.

When Bob asked, “What’s your favorite corner of the dial?”, he also mentioned the challenge hunting below 600 kHz. The implication: whatever is in that section of the band, there are probably not a lot of stations, and they are hard to hear. So, I reasoned in my tiny little brain: “If I hear anything down there, it’s likely to be DX.”

So I tried it, firing up the Grundig Satellit 800 hooked to an MFJ 1886 loop during the daylight hours. With exception of WROW, 590, in nearby Albany, NY, blasting oldies with 5,000 watts, I found nothing . . .  and I do mean nothing: nada, diddly, bupkas, cipher, rien . . . dead band . . . deader than old Jacob Marley. I try it again in the early evening with three different radios with exactly the same results. Nuts.

But then I try again with the Satellit 800/1886 combo at a little after 0900Z and take Bob’s advice about using single sideband. Aha! Carriers 540, 550, and 560. Then at 570, a weird mixture: religious programming in American English over male and female voices in Spanish with time ticks and tones in the background. Is there a time station on this frequency or is it some sort of bleed-over?

On Tuesday evenings I run the Radio Monitoring Net on the 146.94 repeater. During the net, I mentioned the unusual signal I had heard on 570, and W2SRA, an expert DXer, responded with the opinion that this was likely a religious station on Long Island, NY, intermixed with a station known as The Clock from Cuba.

Here’s what Wikipedia has to say about it: Radio Reloj (Spanish for Radio Clock) is a government-owned Spanish-language radio station in Cuba . . . The station is noted for the sound of a ticking clock in the background, with its hosts announcing the time, every minute of broadcast.

I checked the distance from Troy, NY, to Santa Clara, Cuba where the 570 AM station is located; it’s 1449 miles. Wow! According to Wikipedia, the AM transmit power is 50,000 watts

Then I remember that William, KR8L, mentioned that he likes searching above 1620 (another less populated region of the band), so I give that a try. At 1690, I hear oldies, followed by ads for Southern Maryland. The station finally ID’s as WPTX, 1,000 watts nighttime power, in California, MD, a distance of 339 miles. Yes!!

Thanks, Bob and William, for turning me on to some more radio fun!

Bob asks: “What’s Your Favorite Corner of the Dial?”

17 Replies

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

What’s Your Favorite Corner of the Dial?

As asked by Bob Colegrove

Let’s suppose you’ve been listening to radio for a while.  Consciously or not, you’ve probably favored a range of AM, SW, or FM frequencies.  These are areas where you go to DX or just listen to your favorite stations.  One area I seem to keep returning to is the very bottom of the medium wave band, roughly 530 kHz to 600 kHz.  With the convenience of today’s digital radios, I have consciously pushed the envelope somewhat lower.

The main reason for specializing in that frequency range is the challenge.  In the very beginning there didn’t seem to be much at the extreme lower end of the AM broadcast band.  Growing up in Indianapolis in the ‘50s, the local stations were all at the upper end of the mediumwave dial.  WXLW held down 950 kHz – lower than that nothing.  I would say the stator plates on the variable capacitor got very dusty, never being closed any further than that on many radios.

Another challenge was sensitivity.  In analog times, the sensitivity of a tuned circuit had some falloff as the inductance/capacitance (L/C) ratio decreased.  Sensitivity is highest with the variable cap open at the high end of the band.  As you tune lower by increasing capacitance (inductance remaining constant), the Q and consequently sensitivity drop off – not dramatically, but somewhat.

Finally, not all old analog radios tuned to 530 kHz; some were even challenged to tune 540 kHz.  By performing a little mischief with the alignment, I could sometimes venture into unknown territory.

This was all part of the challenge.  So, what could I do to coax some activity out of the bottom of the band?  I spent many hours poring over Bill Orr’s Better Shortwave Reception (Radio Publications, Inc., Wilton, CT, First Edition, 1957) and tweaking caps and coils trying to squeeze the last few kilohertz and microvolts out of my radios.  This exercise fascinated me and became a hobby within a hobby.  If I may be allowed a self-deprecating aside here, the first time I took a radio out of the cabinet, I just assumed that all these alignment screws were loose, and dutifully torqued them down.  The alignment problem is not comparatively complex with today’s digital receivers.  Note, I didn’t say it was unimportant.

I still tend to favor the bottom of the medium wave band.  Below is a list of my catches over the past couple of years.  It’s just a sample of what one might hear by casual listening over time.  Highlighted stations are heard during daylight hours.  This is NOT intended to impress anyone, rather it is hopefully a stimulus for your own efforts.

As another attraction of the lower mediumwave band, you will find a potpourri of stations.  Besides regular North American broadcasting stations, one might possibly hear an occasional high-powered trans-Atlantic station which is not synchronized with the 10 kHz spacing.  530 kHz is interesting.  It is not used in the US by commercial broadcast stations.  Instead, stations from Canada and Cuba at roughly orthogonal directions from me are regularly audible at night on this frequency.  Thus, the radio is tuned by simply rotating the antenna.  530 kHz is also home to several Travelers’ Information Stations (TIS) throughout the country.  Question:  How will this long-time service fare if travelers don’t have AM radios in their new cars?  Finally, the very bottom of the frequency range still contains a few holdouts of non-directional beacons.

Frequencies below 530 kHz probably put a strain on the medium wave bands of old radios, but they are likely no problem on most digital radios having both LW and MW coverage.  As mentioned, there are a few non-directional beacons down there.  They are Morse coded using amplitude modulation.  I have found placing the receiver in SSB mode makes detection much easier, as the heterodyne from the carrier can be heard well before the signal is strong enough to produce any audio.  These beacons generally fade in for brief periods of time and then fade out like passing comets.

My most recent catch was experimental station WI2XLQ, 486 kHz, during its annual Fessenden Event on Christmas Day and again on New Year’s Day.  See https://swling.com/blog/?s=Fessenden+ .  The experience was not the armchair listening quality one might expect from FM or the Internet.  Instead, it was weak and fraught with atmospheric noise.  The station came in periodically, then disappeared, in short, DXing to its highest degree of satisfaction.

The antenna is the key to good reception, and there is no exception to this rule at the lower end of the AM band.  Many years ago, I switched to an indoor, resonant loop antenna.  The selectivity, directional properties, and noise rejection of a loop antenna in this frequency range are superb.  The figure below shows my 40-year-old loop antenna, which is still used in its original form.  It tunes from ~485 kHz through ~1710 kHz in two bands.  The antenna can rotate 360 degrees horizontally and 90 degrees vertically.  Further, it is mechanically balanced to remain in any position without locking.  For those not inclined to construction projects, the Tecsun AN-100, AN-200, and Terk Advantage will perform quite well through inductive coupling with a portable radio’s ferrite bar antenna.

As all experienced medium wave DXers know, for success you need to have patience, “set a spell,” and let the radio do its thing.  Radios are living organisms, kind of like cats, very independent at times, and will let you hear only what they want you to hear.  On many channels, stations will come and go over time.  If you’re lucky, you might catch an ID; lacking that, you might be able to identify it by the format or network.  You might try to compare the contents you hear on the radio with what you can hear online either over the station’s website or via streaming sites such as TuneIn, iHeart, or Radio Garden.  There may be a delay between the Internet stream and the live signal.

When you feel you’ve exhausted the possibilities, there’s still more.  Turn the antenna 90 degrees and start over.  You’re only half finished with that frequency.  Don’t forget a headset or earbuds.

What’s the next challenging rung on the limbo bar?  Well, possibly the 633-meter ham band, 472 to 479 kHz.  I’ll have to pad the old loop with a small capacitor to tune down there.

What’s your favorite corner of the dial?  Why?

KBC Radio leaves DAB+ and moves to 891 kHz

12 Replies

Many thanks to SWLing Post contributor, Gérard Koopal, who writes:

Dear Thomas,

The Mighty KBC has left their DAB+ frequency in the Netherlands and are now changing to MW 891 kHz. from September 1.

The original text From the Mighty KBC is below.

Gérard Koopal
Almere, The Netherlands

The Mighty KBC

August 31, 2024!!!
Today is the last day for The Mighty KBC on DAB+.

Because we have our headquarters outside the EU, we have been refused a license extension, despite the fact that we have been broadcasting on DAB+ for almost 10 years and pay all taxes here.

But from December 1, KBC Radio will be heard on AM 891 kHz.

Just enjoy today:
10:00 – 11:00 The Salty Hour – Marc van Amstel & Bob van Beeten
2:00 PM – 3:00 PM The last hour of Veronica and the North Sea
3:00 PM – 4:00 PM The Salty Hour – Marc van Amstel & Bob van Beeten (repeat)
6:00 PM – 7:00 PM Wind force 6 to 7 – Music from the time of the offshore radio stations
https://www.kbcradio.nl/2020/radio.html

Enjoy real radio!
KBC Radio, Your Hits, Your Station!