Hunting For NDBs In CLE 225

LU - 214 KHz

This coming weekend will see another monthly CLE challenge. This time the hunting grounds will be: 190 - 239.9 kHz PLUS normal NDBs on 'half-way' frequencies nnn.5 kHz (from 190.5 - 999.5 kHz).

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.


A nice challenge in this one is to hear the Abbotsford (BC) NDB, 'LU', on 214 kHz. This is the beacon associated with Abbotsford Int'l Airport, Vancouver International's alternate for foggy conditions. It is located in a breathtaking mountain meadow location at the foot of the North Cascade Mountains. It's 500W Nautel drives a 100' vertical and with all of that space, I suspect a very robust ground system.

'LU' gets out very well and has been heard from Hawaii to New England and should be a good propagation indicator for many North American participants.  Look for 'LU's upper-sideband CW identifier, repeated every 10.4 seconds, on 214.404 kHz with your receiver in the CW mode.

Usually November provides some excellent propagation as the summer thunderstorms have pretty much run their course but the recent warning of upcoming geomagnetic activity may, once again, mean something else in store for us. Often these 'warnings' are not as dire as they might appear and MF propagation remains robust or even enhanced. 

If you are interested in building a system for the new (U.S.) 630m band, the CLE will give you the chance to test out your MF receiving capabilities and compare against what others in your area might be hearing.

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' in Fargo 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 usual 'heads-up':

Hello all,

Do try not to miss our 225th co-ordinated listening event - it starts this
Friday at midday. We can hope for good conditions, some comfortable
listening and opportunities to catch some good DX.
This should be ideal to try out a CLE for the first time.

Days: Fri. 24 - Mon. 27 November, Midday-Midday, your local time

Frequencies: 1) NDBs from 190 - 239.9 kHz

PLUS: 2) Normal NDBs on 'half-way' frequencies nnn.5 kHz
(from 190.5 - 999.5 kHz)

So for all of us it is a CLE in two parts - the first part is hunting for
the NDBs whose published frequencies are lower than 240 kHz.
The second part is hunting for the NDBs whose carrier frequencies
are 'half-way'. E.g. 284.5 DY, 333.5 VOG, 370.5 LB, 381.5 SJX (in MI),
390.5 ITR, 433.5 HEN ( Not nnn.6, etc. )

'Normal' NDBs - no DGPS, please.

(Most Europe listeners will hear few or none from part 1, while
listeners away from Europe will hear few or none from part 2)

The Seeklists from REU/RNA/RWW will help you – you will find them
from the link on the CLE page

Please send your CLE log to the List, if possible as a plain text email and
not in an attachment, showing 'CLE225' at the start of its title. (Loggings
from both parts can be shown together in the same list if you wish)
Please include on EVERY line of your log:

# The date (or just the day 'dd') and UTC (days change at 00:00 UTC).
# kHz - the beacon's nominal frequency.
# The Call Ident.

It is important to show those main items FIRST - any other optional
details such as Location, Distance, etc. go LATER in the same line.

Don't forget to give your OWN location and details of your receiver and
aerial(s), etc. Others will be interested to know, especially new members
- and old ones with memories like mine!

Also, please ALWAYS send your last log with ‘FINAL’ in the subject.
## That is important even if you send no interim logs ##

Listening on the 'half-way' frequencies means we might also catch some
interesting non-CLE beacons - please tell us about those too, but in a
separate list. If any of them are UNIDs whose carriers seem to be on
'half-way' frequencies include them in your main list of course.

Joachim and I will be processing the incoming logs – please look out for
our 'Any More Logs?' email at about 18:00 UTC on Tuesday evening,
with a list to let you check that your log has been found OK.
Joachim will again be making the combined results for us.

Do make sure that your log has arrived on the NDB List at the very latest
by 09:00 UTC on Wednesday 29 November.

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

(If you wish you could use any one remote receiver for your loggings,
stating the location and owner – and with their permission if required.
A remote listener may NOT also use another receiver, local or remote,
to make further 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 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. If you are a member of the ndblist Group, results will also be e-mailed and posted there.

The very active Yahoo ndblist 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 ndblist member to participate in the CLEs and all reports, no matter how small, are of much value to the organizers. 

'First-time' logs are always VERY welcome!

Reports may be sent to the ndblist or e-mailed to either myself or CLE co-ordinator, Brian Keyte (G3SIA), whose address appears above.

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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