AmateurRadio.com

This past week has seen a welcome return to better band conditions on the lower frequencies.

I’ve had my 10' x 20' loop and Perseus SDR combination running a few overnight recordings on the AM broadcast band ... two mornings pointing at Asia and two overnights looking for domestic signals from the east.

The Asian signals have often been very strong, with many signals reaching S9 or higher. I’ve chosen some of the better ones below. Unlike those situated right on the west coast, my location here on Mayne Island gives me a nice shot towards Japan albeit not directly over the ocean, but close enough, as the path crosses islands to my north and then over northern Vancouver Island.

Looking towards eastern North America is a different story, with an unobstructed ocean view from due north to the south east.

As is often the case with overnight recordings, I did not get nearly enough time to thoroughly check them out but one catch caught my attention. It was from WPTX in Lexington Park, Maryland, on 1690kHz. This station supposedly runs 1kW at night and 10kW during the day but on this night (Sept 16), I heard their top-of-hour ID for three consecutive hours! I wonder if someone ‘forgot’ to switch to nightime power or if conditions were just really good? I have heard them again since with two TOH IDs but much weaker and sounding more like a 1kW station should sound!




JOAK - 594kHz in Shobu, Japan (13:30 UTC Sept 20)


JOUB - 774kHz in Akita, Japan (14:00 UTC Sept 20)
(with English lessons)


HLAZ - 1566kHz in Cheju, South Korea (13:30 UTC Sept 20)
(broadcasting in Japanese in this time slot)


Voice of America (VOA) - 1575kHz in Ban Phachi, Thailand (13:30 UTC Sept 20)
(listen for "This is the Voice of America" ID and then into "Yankee-Doodle-Dandy")


                                   ************************

Hunting For NDBs In CLE248

Yes! Another month has passed and it's CLE time once again.

This time the hunting grounds will be: 275 kHz - 425 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.

If you've been meaning to participate in  CLE, then maybe this weekend is a fine time to try! Lately, we've had 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!

At this time of the season, summer lightning storms should be starting to wane and propagation can often be as good as mid-winter if the lightning cooperates.

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:

Hi all

Our 248th Listening Event just squeezes into the last weekend of this month.
Worth waiting for because it is a 'Special', our fifth 'Channels Challenge'.
It's a simple idea, but one that we always seem to enjoy:

    Days:      Friday 27 September - Monday 30 September
    Times:     Start and end at midday, your LOCAL time
    Range:     275 kHz - 425 kHz   (see below)
    Target:    Try to log ANY ONE NDB in each channel

The 'channel' means the NDB's nominal (published) frequency.
EITHER  321.0  OR  321.5 kHz would be OK for channel 321, etc.

So it means a possible maximum of 151 loggings in all, though that would
probably be miraculous, even for the best placed of us!

All the NDBs must be 'normal' ones (no DGPS, Amateur, etc.) and
no UNIDs in your main list.   Yes, it does include those more
challenging frequencies in the DGPS range.

If you want to add extra interest you could also choose to:
    Maximise the number of radio countries you hear    or
    Maximise the total distance to the NDBs you hear    or
    Maximise the number of 'midday' loggings - i.e. NDBs logged
      within 2 hours of midday by your local winter clock time.

It will be extra tough for North American listeners, with their many 'empty'
channels. Southern Hemisphere and Europe listeners should be more lucky.

Our last 'Channels Challenge' was CLE231 in April 2018.
Please look out for the 'Final Details' a few days before the start.

73
  Brian
-------------------------------------------------------------------------
From:   Brian Keyte G3SIA               (CLE coordinator)
ndbcle'at'gmail.com
-------------------------------------------------------------------------
These listening events serve several purposes. They:

courtesy: americanradiohistory.com

The new 'loop' is not really loop-shaped but is rectangular (10' x 20') and more like a Flag antenna shape. I considered a Flag but really don't need any back-end nulling capability since I'm mainly interested in listening to the east and to the north.


The main boom section is composed of two sections of 1" PVC thick-wall (Schedule 40) pipe joined at the center and reinforced with a 10' section of 2" x 2" Douglas Fir. In addition, the boom has a truss of 1/4" Dacron to take out any end-loading sag. The vertical end sections are 3/4" Schedule 40 PVC pipe, fastened with a T at the boom end. The center mast is made of 2" Schedule 40 ABS pipe with a long section of 1 1/2" ABS nested inside that telescopes upward to anchor the truss ropes and give some additional rigidity to the mast.

Main boom and mast construction

This type of construction would lend itself well to anyone interested in a rotating Flag antenna for the BCB / LF or 160m. The costs are very low, the structure is lightweight and the materials are readily available at most hardware outlets.



Looping E/W

Although the preamp is completely sealed and weatherproofed, I still decided to mount it inside a container. The container also provided a convenient anchor to terminate the loop end wires (PVC-coated #18 stranded) without putting any tension on the soldered terminals.

Although I have not had much time to listen, and conditions are still in 'recovery' mode from earlier disturbances, initial indications are that everything is performing as well, if not better, than expected. It certainly outperforms my 10' active shielded loop by a large margin. I have yet to do any serious S/N comparisons between it and my primary LF receive antenna, a large inverted L, which must be tuned to resonance for the desired listening range. I believe that the very quiet loop / Wellbrook combination will provide an overall S/N improvement.

I have always believed that smaller loops provide deeper and sharper front-to-side nulls so I was pleasantly surprised to measure (using Perseus) null depths from 25-30db, on various groundwave signals ... more than expected. Skywave signals also deliver sharp deep nulls in the order of 22 - 25db ... again surprising, but I'll take them!

A brief listen while pointing S-E last evening turned up good signals from 1 kW'ers KYHN (1650kHz) in Fort Smith, Arkansas and KKGM (1630kHz) in Fort Worth, Texas. An early morning listen revealed good audio from JOIK (567kHz) Sapporo, Japan and JOAK (595kHz) in Shobu. Down in the ndb band, little 25-watter 'IP' on 210kHz was an all-time new catch from Mobile, Arizona.

There is still much to learn from this new antenna system but the biggest challenge will be keeping it up all winter. I did lose one of my 10' loops after several years, due to wind, when the main (un-reinforced) PVC mast eventually failed from flexing fatigue. I will tie the ends of the new antenna down when the winds get strong to reduce as much mast flexing as possible. I could however, run the risk of violating another long-standing radio adage ..."if your antenna stays up all winter, it's not big enough". I just can't win.

Part 3 - Loop Listen 

As Murphy would have it, and in spite of the low amount of solar activity, LF/MF propagation has been very poor since getting my new 10' x 20' loop in place. The few front-to-side nulling checks that I have done, have produced results varying from around 20db to 30db, depending upon the signal. I suspect the depth of null is also affected by the signal's arrival angle but there is still more to learn. The pattern seems to be very close to that of a typical circular loop...the classic figure-8 pattern illustrated below as shown on the Wellbrook data that came with my ALA100LN preamp.

Courtesy: http://www.wellbrook.uk.com

More typically, the null is around 21-22 db as shown on this test while listening to the ground wave carrier of the 'YZA' NDB (236kHz) located in Ashcroft, B.C., about 150 miles to the NE. As expected, the null is fairly sharp and the front / rear lobe, fairly broad.



One short check at dusk produced nice signals from  CJBC, the French-language station in Toronto. The past few nights it has been very strong but with a strong echo effect. I wonder if there is more than one CBC outlet here (860kHz), such as a low-power repeater, causing the echo.



At the same time, while still fairly light outside, WCCO in Minneapolis had a nice signal just before sunset.



No matter how poor conditions become, it seems that the Hinchinbrook (Alaska) NDB, 'ALJ' (233kHz), is always strong ... looping north.

Courtesy: https://www.google.ca/maps

My apologies for the video quality. If you know of any software available for making full-screen Perseus video captures so that I might improve my technique, please let me know. Presently I am just capturing them on my I-Pad which leaves a lot of room for improvement.

(Since originally posting the above, I have been using the Tiny Take free screen capturing software, to produce better quality catures of my Perseus recordings. It's also probable that my new iPhone would produce a high quality video of my computer screen compared to the older iPad used for these ones, but it's something yet to be tried.)

Hopefully conditions will only get better as the season progresses and I am able to give the loop a good workout ... before it gets too windy!

Ionosphere:  source

One of the Broadcast Band’s (BCB) six ‘graveyard’ frequencies is 1240 KHz.




These frequencies (1230, 1240, 1340, 1400, 1450 and 1490 KHz) are assigned to smaller stations running non-directional antennas and up to 1000 watts of power. In North America, there are typically about 150 stations assigned to each frequency.

The origin of this spooky name is often a source of debate. Some suggest that it comes from the cacophony of strange howls and sounds that can be heard on these frequencies at night, as multiple fading signals fight it out to be heard, while others relate it to the similarity of the jam-packed headstones in a typical graveyard. Whatever the true reason, it's a fascinating part of the BCB to explore.

Most BCB DXers enjoy the challenge of tackling the graveyard frequencies as they're often so busy. New stations will fade in for a brief period only to be replaced by a totally different one a few moments later ... and then a different one soon after. It gets even better if the fade-ups coincide with a local ad or a ‘top-of-hour’ ID, putting a new catch in the log!

Several days ago I reactivated my 10’ x 20’ loop and Wellbrook ALA100N preamp, that I use for NDB and BCB DXing, by adding a new buried coax line from the shack.





I had previously re-appropriated the loop’s coax for a nearby HF wire antenna and had been without the loop all winter.


After BCB DXer Mike Cherry (VE7SKA) on Salt Spring Island, the next island to the west of me, described some of the European action that he had experienced last winter, I am determined to not miss out during the next winter's BCB DX season!

10' x 20' Loop & Wellbrook ALA100N Preamp

Once getting the loop powered-up in mid-afternoon, I decided to give it a test by making a ‘deep-search’ on 1240 KHz.

At 1500 hours local time, I wasn’t hearing any audio on 1240 but a weak carrier could be detected audibly. Using my Perseus SDR’s waterfall in its narrowest possible window, produces an extremely narrow passband, effectively increasing the sensitivity by a huge factor. This allows the waterfall to display weak signals that are presently being propagated to my location but far too weak to be heard by ear. I’m estimating that in this narrow bandwidth, it can dig about 30 dB or more into the noise, but there is a price to be paid for this extra gain .... time!

If you're used to watching your receiver’s waterfall scroll along quickly, this mode is just the opposite. It moves in very slow increments, allowing the weaker signals to build up enough to be visible before taking the next deep look. The screen capture shown below is a result of a three-hour listening period, from 1500-1800 hours local time. The entire waterfall is 25 Hz wide, with each tick representing 1Hz.

3-Hour Daylight Deep Search

Although no signals were clearly audible during this period, my deep-search revealed the carriers of ~28 different stations being received here in south-west British Columbia ... in the middle of a summer afternoon! It’s interesting to note that few of these signals are 100% stable and several can be seen really struggling to maintain their exact assigned frequency. In this highly narrow bandwidth view, even the worst drift amounts to no more than a Hertz, well within the required tolerance of +/- 20Hz.

Using the always-reliable MWLIST, the locations of the most likely candidates for these 28 signals are plotted below. These are the 28 nearest stations and with my loop pointing east, a definite east / south-east flavour is evident.


At mid afternoon, one might expect to see only groundwave-propagated signals on the broadcast band. Midday groundwave on the broadcast band can easily travel a few hundred kilometers, gradually growing weaker over the longer paths. Perhaps all of these signals are arriving via this mode as they are at least 20-30dB into the noise. I initially thought that some of the further-out signals were being reflected from a strong daytime D-layer, although most of the energy would be absorbed. Further reading shows detectable groundwave up to 1200km is possible which coincides nicely with the distances observed. Most likely what I'm seeing is a combination of extended groundwave and D-layer refraction on the furthest signals.

The second screen capture shows the same frequency for another three hours, starting about an hour before local sunset. Some of the weaker signals seen earlier now begin to grow in strength as the D-later absorption starts to decay and reveal the higher E-layer. By the end of the third hour, an additional 41 stations have appeared for a total of 69 carriers cantered on 1240 KHz. (note that my Perseus calibration is off by a few Hz)

3-Hour Sunset Deep Search

The next 41 closest stations are now plotted below in yellow, showing the most likely source of these signals. The distances illustrated are in-line with single and double-hop E-layer or possibly lower F-layer refraction.



This view shows the directional pattern of the front of the loop while pointing east, with its very broad circular lobe. In this direction, the narrow null is only seen along the coast.



It will be interesting to do a mid-winter follow-up on 1240 and compare the present summer propagation to the much better winter conditions. I expect that a some point, propagation via the higher F-layer will be present and extend skip distances out to the east coast or to South America.

In the meantime, things are almost ready for some pre-sunrise looks to the west and some overnight top-of-hour recordings ... as soon as I re-calibrate Perseus!

courtesy: NOAA

Last weekend’s CLE240 saw mediocre propagation for North America and European listeners alike.





It seems that our monthly CLE schedule continues to be synced with the Sun’s monthly rotational period that has been regularly lining us up with the same massive coronal hole, elevating earth-directed solar wind speeds now for several months.

Several CLE participants in the USA commented on the lack of any propagation into BC, further fueling my long-held belief that BC seems particularly sensitive to any geomagnetic activity in the auroral zone to our north. The auroral activity always seems to dip further to the south here for some anomalous reason, as listeners just a few hundred miles to the south or southeast see far less absorption than is observed here.

With a few exceptions, the main effect of these conditions is to largely kill the normal east-west propagation path and just allow single-hop signals from the south or the SE/NW to dominate. Typically, the path to the Pacific is not affected and can often be enhanced.

As a side observation, this past weekend was also the CQWW 160m DX contest and, as one left-coaster commented, conditions were the “worst seen in 10 years”. One would expect to see much better conditions and a much quieter Sun at this point in the solar cycle!

With fingers crossed for better propagation during the next CLE, here is what was logged over the three-night listening event from my location here in BC’s Southern Gulf Islands using a Perseus SDR and an Inverted-L antenna resonated to 400 kHz:

26 05:00  385     QV            Yorkton, SK, CAN
26 07:00  385     OCC         Yakutat, ALS
26 09:00  385     MR           Pacific Grove, CA, USA
26 09:00  385     EHM         Cape Newenham, ALS
27 07:00  385     CPZ          Chaparrosa Ranch, TX, USA
26 07:00  386     SYF           St. Francis, KS, USA
26 09:00  386     HAU         Helena, MT, USA
26 06:00  388     OK           Preston, OK, USA
26 07:00  388     MM          Fort Mc Murray, AB, CAN
26 07:00  388     JW           Pigeon, AB, CAN
26 06:00  388     CDX         Somerset, KY, USA
26 06:00  389     YWB         Kelowna, BC, CAN
26 04:00  389     TW           Twin Falls, ID, USA
26 07:00  389     CSB          Cambridge, NE, USA
26 07:00  390     HBT          Sand Point, ALS
26 11:00  390     AES          Northway, ALS
26 04:00  391     TK            Telkwa, BC, CAN
26 11:00  391     GXD          Nacogdoches, TX, USA
26 07:00  391     EEF           Sisters Island, ALS
26 06:00  391     DDP          Dorado, PTR
26 09:00  392     ZFN           Tulita, NT, CAN
26 05:00  392     PNA           Wenz, WY, USA
26 05:00  392     ML            Charlevoix, QC, CAN
26 08:00  392     FMZ          Fairmont, NE, USA
26 10:00  393     UKS           Kosrae, FSM
26 04:00  394     RWO         Kodiak, ALS
26 07:00  394     DQ            Dawson Creek, BC, CAN
26 07:00  395     YL             Lynn Lake, MB, CAN
26 04:00  395     ULS           Ulysses, KS, USA
26 07:00  395     5V             Drumheller, AB, CAN
26 07:00  396     YPH           Inukjuak, QC, CAN
26 05:00  396     CRS          Corsicana, TX, USA
26 05:00  396     CMJ          Ketchikan, ALS
26 07:00  397     ZSS            Saskatoon, SK, CAN
27 12:00  397     SB             San Bernardino, CA, USA
26 10:00  398     YOD         Cold Lake, AB, CAN
26 06:00  398     3D            Cumberland House, SK, CAN
26 11:00  399     ZHD         Dryden, ON, CAN
26 11:00  399     SRI           Pribilof, ALS

A summary of results for all participants can be found here, at the ndblist info site.

BF-362 Seattle

courtesy: NOAA

My log consisted of 30 stations, with all but two from Friday night before the storm. As usual, the receiver was a Perseus SDR and an 'Inverted-L', resonated at 300 kHz.
25 12:00  350     SWU   Idaho Falls, ID, USA
25 08:00  350     RG   Oklahoma City, OK, USA
25 07:00  350     NY   Enderby, BC, CAN
25 07:00  351     YKQ   Waskaganish, QC, CAN
26 12:00  352     RG   Rarotonga IAP, CKS
25 07:00  353     ZXY   Whitehorse, YT, CAN
25 08:00  353     PG   Portage La Prairie, MB, CAN
25 13:00  353     LLD   Lanai Island, HWA
25 07:00  353     AL   Dixie, WA, USA
25 12:00  355     AUB   King Salmon, ALS
25 12:00  356     ZXE   Saskatoon, SK, CAN
25 08:00  356     ZF   Yellowknife, NT, CAN
25 08:00  356     PND   Portland, OR, USA
25 08:00  356     ON   Penticton, BC, CAN
25 12:00  356     MEF   Medford, OR, USA
25 09:00  358     SIT   Sitka, ALS
25 09:00  359     YQZ   Quesnel, BC, CAN
25 09:00  359     YAZ   Tofino, BC, CAN
25 07:00  361     HI   Holman, NT, CAN
25 07:00  361     E3   Wabasca, AB, CAN
25 07:00  362     YZS    Coral Harbour, NU, CAN
25 07:00  362     RPX   Roundup, MT, USA
25 07:00  362     BF   Seattle, WA, USA
25 08:00  362     6T   Foremost, AB, CAN
25 07:00  365     YGZ   Grise Fiord, NU, CAN
25 12:00  365     MA   Mayo, YT, CAN
27 08:00  365     DPY   Deer Park, WA, USA
25 07:00  365     AA   Harwood, MN, USA
25 12:00  368     ZP   Sandspit, BC, CAN
25 12:00  368     VX   Dafoe, SK, CAN

The results from ALL participants may be viewed here.