Hunting For NDBs In CLE265

WC - 332 White Rock, BC

It's almost CLE time once again! 'CLE's are 'Co-ordinated  Listening Events, and NDB DXers around the  world focus their listening time on one small slice of  the NDB spectrum. 
This time around the hunting ground is the entire NDB spectrum ... and it has five challenges!
When tuning for NDBs, put your receiver in the CW mode and listen for the NDB's CW identifier, repeated every few seconds. Listen for U.S. NDB identifiers approximately 1 kHz higher or lower than the published transmitted frequency since these beacons are modulated with a 1020 Hz tone approximately.

For example, 'AA' near Fargo, ND, transmits on 365 kHz and its upper sideband CW identifier is tuned at 366.025 kHz while its lower sideband CW ident can be tuned at 363.946 kHz. Its USB tone is actually 1025 Hz while its LSB tone is 1054 Hz.

Often, one sideband will be much stronger than the other so if you don't hear the first one, try listening on the other sideband.

Canadian NDBs normally have an USB tone only, usually very close to 400 Hz. They also have a long dash (keydown) following the CW identifier.

All NDBs heard in North America will be listed in the RNA database (updated daily) while those heard in Europe may be found in the REU database. Beacons heard outside of these regions will be found in the RWW database. These databases have recently been re-vamped and are slicker than ever before!

From CLE coordinator Brian Keyte (G3SIA), comes the following CLE info:


Hello all

We have something special for our 265th Listening Event, now less than a week away.

     Days:      Friday 19 February - Monday 22 February

     Times:    Start and End at midday, your LOCAL time


It is just 20 years since fully-organised CLEs started.  Encouraged by Alan, to mark the anniversary Joachim and I have five separate, new, and mostly gentle ‘Challenges’ for you!

They are all based of ’20-ness’.   Whether you have enjoyed 20 years of our CLEs, or are thinking of trying your very first, this CLE should be a good one. 

                  CHALLENGE 1.   20  NDBs ( N )   Log any 20 NDBs located in any ONE RADIO COUNTRY of your choice. 


    CHALLENGE 2.   20  Radio Countries ( C )   Try to log ONE NDB from each of:

        listeners in Europe:       20 different EU radio countries

        listeners in N America: 20 different USA/CAN States/Provinces

        listeners elsewhere:     20 different radio countries


               CHALLENGE 3.   20  re-logged OLD NDBs ( O )  Try to log any 20 of the NDBs that were also logged in our first formal Event - CLE003, 20 years ago.

       In the Final Details a list will be provided of the 80 CLE003 loggings of NDBs in Europe and N America that are still probably active.


               CHALLENGE 4.   20  ‘n20 kHz’ loggings  ( K )   Try to Log a total of 20 NDBs on the ‘n20’ kHz frequencies

        i.e. on 220 kHz and 320 kHz and 420 kHz and 520 .. .  . up to 1220 kHz (as possible!)

       (The other four challenges can use the whole NDBs frequency range)         


    CHALLENGE 5.   20 loggings at 20:-- hrs  ( H )   Log a total of 20 NDBs between 20:00 and 20:59 LOCAL time during the CLE.  

       (If you find the challenges a bit too gentle, there will be an alternative hard version of this 5th one.

        We will explain in the Final Details)

How will you set about tackling those different kinds of listening?   Some ways are good, others not-so-good, perhaps prompting some questions from you!

About two days before the start, the Final Details will have some answers and suggestions and full advice on tackling your listening and log-making.

So the Final Details will explain how one logging CAN satisfy more than one Challenge without any problems, but, as always, each NDB must appear only once in a CLE log.

 (If you are interested in what was going on 20 years ago I’ve added a short ‘Background for Historians’ below)

Background for Historians!  

Alan Gale still has archive information about what was going on 20 years ago.

At that time several of us were thinking about trying out some coordinated listening.

For example, early in 2001 Bill Hohnstein wrote “What would seem interesting to me would be to have a weekend (certain days) where ndblist would sponsor concentrated monitoring of a 10 – 20 kHz segment of the LF NDB range with everyone reporting their results” and Lionel Roithmeir organised an event for 2182 kHz monitoring.   Andy Robins, Michael Oexner, Morris Sorensen, Kathleen Redding, Brian Keyte and others contributed further ideas.

We were talking about ‘Coordinated Monitoring Events’ or CMEs.

We had an informal ‘CME’ on 20-21 January listening on 380-400 kHz.  There were logs from Alan, Kathleen and Brian (all ENG), Roger Caird (IRL), Andy, Bill, Dave Tomasko, Douglas Klein, Ken Zichi and Phil Atchley (all USA), and Morris (CAN)

Phil rescued us from the ‘CME problem’!   He wrote “I have one big suggestion. Let's change the name from CME to CLE, Coordinated Listening Event".  Every time I see CME in a message subject line I think a CME "Coronal Mass Ejection" has just taken place.”

Then on 3-4 February we were also joined by Bo Nenson (SWE), Christoph Mayer and Norbert Reiner (both DEU), Lionel and Mike Trodd (both ENG), Bob Parsons and Chris Steele (both USA) for a second informal Event which we called a ‘CLE’.



It was three weekends later, 23rd - 25th February 2001, and exactly 20 years ago, when we had our first ‘recognisable’ CLE (335 – 344.9 kHz), later labelled CLE003.   A grand total of 23 of us joined in with good participation from Europe and North America.  196 different NDBs were logged and ‘Combined Results’ were made, looking a bit like our present ones.


Michael Oexner, Roschbach

Morris Sorensen, Winnipeg

Jean Jacquemin, Merville

Rodney Valdron, New Brunswick

Pat Vignoud, SE France

Phil Atchley, Merced, Central CA

Tore Ekblom, Nr Helsinki

Dave Tomasko, Chicago

Lionel Roithmeir, Guernsey

Andrew Robins, Kalamazoo

Alan Gale, Lancashire

Doug Klein, Hastings

Brian Keyte, mid Surrey

Bill Hohnstein, Nr Lincoln

Kathleen Redding, NE London

Bob Parsons, Gloucester City, NJ

Mike Trott, W. Sussex

Jack Woods, Oregon

Robert Connolly, Kilkeel

Chris Steele, while at Ft Worth

Costas Krallis, Athens


Roger Caird, Dublin


Bo Nensen, Ornskoldsvik



Good listening
    Brian & Joachim
From: Brian Keyte G3SIA          ndbcle'at'
Location: Surrey, SE England     (CLE co-ordinator)

If you are interested in some remote listening - maybe due to local difficulties - you could use any one remote receiver for your loggings, stating its location and with the owner's permission if required.( e.g. see ) A remote listener may NOT also use another receiver, local or remote, to make more loggings for the same CLE.

These listening events serve several purposes. They

• determine, worldwide, which beacons are actually in service and on-the-air so the newly-re-vamped Rxx online database can be kept up-to-date

• determine, worldwide, which beacons are out-of-service or have gone silent since the last CLE covering this range

• will indicate the state of propagation conditions at the various participant locations

• will give you an indication of how well your LF/MF receiving system is working

• give participants a fun yet challenging activity to keep their listening skills honed

Final details can be found at the NDB List website, and worldwide results, for every participant, will be posted there a few days after the event.

The NDB List Group is a great place to learn more about the 'Art of NDB DXing' or to meet other DXers in your region. There is a lot of good information available there and new members are always very welcome. As well, you can follow the results of other CLE participants from night to night as propagation is always an active topic of discussion.

You need not be an NDB List member to participate in the CLEs and all reports, no matter how small, are of much value to the organizers.

Remember - 'First-time' logs are always VERY welcome!

Reports may be sent to the NDB List Group or e-mailed to CLE co-ordinator, Brian Keyte (G3SIA), whose address appears above. If you are a member of the group, all final results will also be e-mailed and posted there.

Please ... give the CLE a try ... then let us know what NDB's can be heard from your location! Your report can then be added to the worldwide database to help keep it up-to-date.

Have fun and good hunting!
Steve McDonald, VE7SL, is a regular contributor to and writes from British Columbia, Canada. Contact him at [email protected].

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