Hunting For NDBs in CLE250

YMW - 366 courtesy:

There is no doubt that as one ages, the passage of time seems to accelerate. Didn't we just have a CLE a couple of days ago?? In any event, this weekend finds CLE 250 focusing on 350.0 - 369.9 kHz, in search of NDBs.

For those unfamiliar with this monthly activity, a 'CLE' is a 'Co-ordinated Listening Event', as NDB DXers around the world focus their listening time on one small slice of the NDB spectrum.

If you've been meaning to participate in  CLE, then maybe this weekend is a fine time to try! We continue to have  a lot of first time submissions so you won't be alone!

As well, if you're trying to learn CW, copying NDBs is perfect practice as the identifier speed is generally slow and the letters are repeated again every few seconds!

A nice challenge in this one is to hear YMW - 366 kHz. 'YMW' is located in southwest Quebec, near Maniwaki.

'YMW' runs 500W into a massive vertical and is well-heard throughout North America as well as in Europe. Listen for its upper-sideband CW identifier repeated every 10 seconds (with your receiver in the CW mode) on 366.398 kHz.

This past week has seen the best propagation of the season so far. Hopefully it will extend into the CLE weekend ... but, it will be interesting to see if our CLE once again gets whacked by the Sun, just as it gets started. This has been the case for the past several CLEs as our monthly schedule seems synced with some nasty coronal hole on the Sun, also on a ~ 27 day cycle!

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.

From CLE organizer Brian Keyte, G3SIA, comes the details:

Our 250th Co-ordinated Listening Event is almost here. 
Can new 'listening eventers' join in too?  YES, PLEASE!  Joachim and I are
always pleased to help first-time CLE logs through the harvester program.

    Days:    Friday 22 November - Monday 25 November
    Times:   Start and End at midday, your LOCAL time
    Range:   350.0 - 369.9 kHz

Please log all the NDBs you can identify that are listed in this range (it
includes 350 kHz but not 370) plus any UNIDs that you come across there.
You can find full information to help you, including seeklists made from
RNA/REU/RWW, by going to the CLE page
and clicking on SEEKLIST.

Please send your 'Final' CLE log to the List, if possible as a plain text
email and not in an attachment, with 'CLE250' and 'FINAL' at the start of
its title.
Please show the following main items FIRST on EVERY line of your log:

  #   The full Date (e.g. 2019-11-22)  or just the day number (e.g. 22)
         and UTC (the day changes at 00:00 UTC).
  #   kHz  - the beacon's nominal published frequency, if you know it.
  #   The Call Ident.

Optional details such as Location and Distance go LATER in the same line.
If you measure LSB/USB offsets and cycle times they are useful too.

Please always include details of your own location and brief details of the
receiver, aerial(s) and any recording equipment you were using, etc.

Joachim or I will send the usual 'Any More Logs?' email at about 20:00 UTC
on Tuesday so you can check that your log has been found OK.
Do make sure that your log has arrived at the very latest by 09:00 UTC on
Wednesday 27 November.   We hope to make all the combined results
within a day or so.

Good listening
From:      Brian Keyte G3SIA        ndbcle'at'
Location:  Surrey,  SE England       (CLE coordinator)

(Reminder:  If you wish you can use a remote receiver for your loggings,
  stating its location and owner - with their permission if required.
  A remote listener may NOT also use another receiver, whether local or
  remote, to obtain further loggings for the same CLE)

These monthly listening events serve several purposes. They:
  • determine, worldwide, which beacons are actually in service and on-the-air so the 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

The NDB List Group is a great place to learn more about the 'Art of NDB DXing' or to meet other listeners 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].

One Response to “Hunting For NDBs in CLE250”

  • Vic KB7GL:

    Sounds like a fun event. Many of the stand-alone 400 Watt NDBs have become part of history…not too many left.

    Many of the 400W NDBs evolved from the old LF Radio Range sites. Typically, the NDB used the center tower from the 5-tower array.

    On my QRZ page, there is a picture of a typical LF Range transmitter, and the goniometer removed from the Neah Bay, WA LF Range when it was decommissioned in 1945. It became a 400W NDB site (EBY) and was eventually also decommissioned several years ago. Mostly, only boaters were using it.

    73, Vic KB7GL

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