Tag Archives: DXing

Bob’s Radio Corner: It’s DX Season

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Noted by Bob Colegrove

In the Northern Hemisphere the nights continue to get longer as we approach the winter solstice; we gain an hour of early evening darkness on Sunday, November 2nd; the summer atmospheric disturbances are nearly gone; propagation is better.  It’s time to set aside the activities of summer and once more dive underneath the headsets.

DXing is not the same thing as listening.  For listening you position yourself in a nice recliner with the radio on a table beside you.  You set the radio to ATS and scan the available fare.  You select one of the more interesting results and, together with your favorite beverage, listen to the programming.  DXing, on the other hand, requires well planned work and lots of patience.  Critics might say it also requires some imagination; however, I have always tried to be honest with myself and ask if what I am hearing is truly QSLable.

Sir Oswald Davenport, intrepid DXer and Chairman,
National Association of Armchair Adventurers

Don’t get me wrong, I listen a lot, but I also DX.  Living on the East Coast of NA, I often direct my antenna toward Asia and the Pacific hoping to hear Japan and New Zealand.  However, more often than not, these have proven to be illusive.  DXing is like fishing.  Often, you pull up an old boot or find the bait is gone.  Further, the sound quality of a true DX signal will have no appeal to an audiophile.  It is intentionally weak and subject to fading.

So, you get your wins when you can.  Last February I scanned the 49-meter band stopping at 6130 kHz to identify some faint pop/rock music.  There were two possibilities, a Chinese station and Radio Europe.  If you have never heard of Radio Europe, it is in Alphen aan den Rijn, The Netherlands, and has a rather imposing name for a modest 1 kW station.  It is targeted to Western Europe, and is listed in HFCC, B25.  The station is identified periodically in English by a dramatic baritone male announcer.  The recording was made at 0211 UTC on February 6, 2025.  The announcement begins 9 seconds into the clip; Radio Europe is mentioned at 23 seconds.

The curious thing is Radio Europe is not necessarily well received at the U. of Twente SDR site just 100 miles away.  Science notwithstanding, there is simply no accounting for propagation.

Well, Radio Europe is back this season as strong as I have heard it, and if you’re a NA East Coaster, you might give it a try from 2300 UTC on.  I see it was reported in Florida in 2023.  Using exalted carrier single sideband (ECSS) (SSB in simpler terms) seems to produce the best results.  Despite low power and long distance, it’s occasional stations like Radio Europe that keep this DXer fishin’.  For a clear sample, it streams here http://p.liveonlineradio.net/?p=radio-europe.

Good DXing ’25-’26.

Dexter D. Xer

From Missouri to Oklahoma: Discovering America’s Secure Nets on 5140 kHz

1 Reply

Many thanks to SWLing Post contributor Don Moore–noted author, traveler, and DXer–who shares the following post:

Icom IC-756 Pro Transceiver DialThe Missouri and Oklahoma Secure Nets

By Don Moore

Don’s traveling DX stories can be found in his book Tales of a Vagabond DXer [SWLing Post affiliate link]. If you’ve already read his book and enjoyed it, do Don a favor and leave a review on Amazon.

I’m always looking for new stations to add to my logbook, and the more unusual, the better.  So I was intrigued by a pair of messages in the Utility DXers Forum (https://www.udxf.nl/) email group in mid-August. Steve Handler posted a list of emergency station call signs from the state of Missouri that he found on the web in a 2014 emergency plan document. Then Jack Metcalfe responded that the last time he had checked, in early 2024, they ran a regularly scheduled net on 5140 kHz.

I immediately sent an email to Jack to find out more. He answered that on Wednesdays the Oklahoma State Secure Net had been doing a check-in at 0900 local time and that the Missouri State Secure Net followed at 0930 local time. Both of these started on 5140 kHz and then moved to 7477 kHz.

Going After the Secure Nets

I was spending my summer at an Airbnb in the north suburbs of Chicago. It wasn’t a good place to DX from, but I had already found a good listening site at the Old School Forest Preserve near Libertyville, Illinois. I began a series of regular Wednesday morning listening sessions. I knew that this wasn’t the best time of year for reception on lower frequencies, but I wanted to give it a try.

All I got from the Oklahoma net was a few very weak and unreadable signals. From the Missouri net, I got two loggings of the net control station, WNBE830, and of WQKX373 in St. Charles County. Two other Missouri stations did check in, but they were too weak for me to copy the call signs. They did say that the net is only on the first and third Wednesdays of the month. And there was nothing on 7477 kHz, so they apparently stick to 5140 kHz only now.

Recording of WNBE830 as heard on 5140 kHz at 1430 UTC on 03 September 2025, as heard in Old School Forest Preserve:

In mid-September, I left Chicago to visit my daughter in western Colorado. While I was planning my return drive back east along I-70, I realized that I would be spending the night of Tuesday, October 14, somewhere around Kansas City. And that meant I would be in the area the next morning for the third Wednesday of the month. I made plans for another mini DXpedition.

I found a hotel in the west suburbs and the next morning headed to a picnic shelter in nearby Wyandotte County Park for another remote DX session with my Airspy HF+ Discovery SDRs and PA0RDT mini whip. It was an excellent location. I logged five stations participating in the Oklahoma net. During the initial chitchat before the roll call, it was mentioned that some of the participants were at a conference. I might have gotten more stations if it hadn’t been for that. The Missouri net, on the other hand, did not make an appearance even though it was the third Wednesday.

Recording of roll call in the Oklahoma State Secure Net on 5140 kHz at 1407 UTC on October 15, 2025, as heard in Wyandotte County Park.

How To Log the Secure Nets

I didn’t hear as many new stations as I had hoped, but then I was listening in late summer and early autumn. There had already been several hours of daylight before the net started, which isn’t the best for propagation on the lower shortwave frequencies. The northern hemisphere is moving into winter, and as that happens, sunrise times will move later. And that will allow 5140 kHz to be heard at greater distances during the timeslot these nets are on. If you can hear WWV on 5 MHz in mid-morning in mid-winter at your location, you should have a chance at these.

The nets are on at 0900 and 0930 local (Central) time. When I was tuning in, that was 1400 and 1430 UTC, but when the US goes off of Daylight Savings Time on November 2nd, that changes to 1500 and 1530 UTC. From what one of the Oklahoma stations said, it sounded like the Oklahoma net is on every Wednesday. The Missouri net did say only first and third Wednesdays, but according to Jack Metcalfe, it was weekly some years ago. And for some reason, they weren’t on the third Wednesday of October.

I’m going to be spending the next four months traveling in Southeast Asia, so I won’t be DXing these again until I return to Chicago for a short visit in March. But hopefully some of you reading this in North America will try to hear these networks, too. Given that there is some question as to which Wednesdays these networks take place, I suggest setting up your SDR to make a spectrum recording including 5140 kHz every Wednesday at 1400/1500 UTC for the next few months. And let me know what you hear by dropping me a message to Don AT DonMooreDXer DOT com. If I get enough good information, I’ll put together an update to this article.

And that brings up something else. Do you know of any other regularly scheduled utility voice networks on shortwave like this one? Over twenty years ago, the US Army Corps of Engineers and the Federal Aviation Administration had weekly voice nets, but those are long gone.

Please post what you know in the comments or send me an email to the above address.

Oklahoma Secure Net Stations

On logs going back to 2005, these are the stations that Jack Metcalfe has heard participating in the net.

  • KNBV428 Santa Fe, NM
  • KNFG267 Oklahoma City, OK (normal net control)
  • KNGR728 Rush Springs, OK
  • WGY926 Oklahoma City, OK
  • WNBM839 Stillwater, OK
  • WNCH624 Department of Emergency Management, Tulsa, OK
  • WNPV700 Durant, OK
  • WNUW211 Oklahoma City, OK
  • WNUW212 Department of Emergency Management, Shawnee, OK
  • WNUW213 Department of Emergency Management, Altus, OK
  • WNUW215 Ponca City, OK
  • WNUW216 Oklahoma City, OK
  • WNUW217 Ardmore, OK
  • WPBV938 Beaver, OK (Beaver County EOC)
  • WPFY721, Oklahoma Emergency Management Agency EOC at the National Guard Armory, Seminole, OK
  • WQSY836 Byng, OK

My logs include three more stations either participating in or being unsuccessfully called.

  • WQYW833 Unknown location
  • WQZT582 Broken Arrow
  • WSHM692 Oklahoma City

Missouri Secure Net

Stations Jack Metcalfe has logged.

  • WNBE830 Ike Skelton Training Center, Jefferson City, MO (net control)
  • WNUW240 Missouri EMA, Jefferson City, MO
  • WQKE203 Missouri Dept of Transportation, Jefferson City, MO
  • WQOI753 Missouri Dept of Transportation, Hannibal, MO
  • WQOI754 Missouri Dept of Public Safety, Sikeston, MO
  • WQOJ557 Missouri State Police Radio Shop, Jefferson City, MO
  • WQOL350 Missouri Dept of Public Safety, Chesterfield, MO
  • WQOL459 Missouri Dept of Transportation, Lee’s Summit, MO

I heard one additional station:

  • WQKX373 St. Charles County, MO

Next listed are the stations Steve Handler found listed in the 2014 edition, Appendix 2, Section 2.22 of the 2014 Emergency Operations Plan. This plan was publicly posted by the City of Battlefield at the following URL:

https://core-docs.s3.us-east-1.amazonaws.com/documents/asset/uploaded_file/4319/CBM/3591786/complete_emergency_operations_plan.pdf

  • KNNT320 Boonville, MO
  • KNNT321 Greenwood, MO
  • WNUW238 Battlefieldd, MO
  • WNBE824 Jackson, MO
  • WNBE825 Rock Port, MO
  • WNBE826 Lee’s Summit, MO
  • WNBE827 Macon, MO
  • WNBE828 St. Louis, MO
  • WNBE829 Springfield, MO
  • WNBE830  Jefferson City, MO
  • WNBE831 Poplar Bluff, MO
  • WNBE832 St. Joseph, MO
  • WNBE833 Willow Springs, MO
  • WNBE834 Raytown, MO
  • WNBE835 St. Charles, MO
  • WNBE836 Hillsboro, MO
  • WNBE837 Neosho, MO
  • WNUS448 Union, MO 64084
  • WNWU734 St. Joseph, MO
  • WPCY526 Kansas City, MO
  • WPBN258 Kirkwood, MO
  • WNZJ459   Belton, MO
  • WPES740  Camdenton, MO
  • WPGA369 Fort Leonard Wood, MO
  • WPKX561 Hermann, MO

According to the same document, the net is authorized to use the following frequencies. Under 7477 kHz, there is a note that the station uses 1000 watts during the day and 250 watts at night.

2326, 2411, 2414, 2419, 2439, 2463, 5140, 5192, 7477, 7802, 7805, and 7935 kHz.

A big thanks to Jack Mecalfe for his assistance with this and to Steve Handler for making the initial post that drew my interest. 

DXing . . . bats?!!

4 Replies

by Jock Elliott, KB2GOM

Just how hardcore are you as a DXer?

I received the following from a ham radio friend:

Greetings all!

I received an interesting opportunity for anyone capable and interested
in helping NYS DEC. This was aimed at Warren County, however I thought
hams in the Northern District surrounding counties could also assist,
particularly Saratoga and Washington counties:

We were recently contacted by a representative of NYS DEC, Fish and
Wildlife Division requesting the assistance of the amateur radio
community. The DEC will be releasing approximately 20 bats with
transmitters attached and hope to track them to their summer roosting
locations. They are scheduled to be released on April 22 at Hague, NY.
The frequencies for these transmitters will be in the 150-151MHz range
and are included below. They will emit about 35 pulses per minute. The
idea is to set up your radio to scan the frequencies (by entering each
one, or scanning from 150-151MHz in 1KHz steps). Should you get a “hit”,
note the frequency and cross it to the serial number of the transmitter.
Note the date and time and report it to me.

This sounds like a fun exercise and we will be helping the DEC as well.
If you think you will be participating, let me know. I’d like to report
back to the DEC representative with an approximate head county.

Thanks and ’73

Mark KD2RJP

Serial # Frequency
276481 150.052
276482 150.075
276483 150.109
276484 150.172
276485 150.192
276486 150.272
276487 150.290
276488 150.351
276489 150.391
276490 150.429
276491 150.449
276492 150.513
276493 150.549
276494 150.571
276495 150.592
276496 150.670
276497 150.690
276498 150.751
276499 150.794
276500 150.829
276501 150.850
276502 150.875
276503 150.916
276504 150.951
276505 150.990

Update:
The release date has been moved to April 22.
One thing I didn’t mention in the original emai l: the transmitters
will work for about 2 weeks. So please scan when and where you are able
to within the 2 week period. Also, many radios do not have the ability
to tune in 1 KHz steps so your radio may not be able to monitor all the
transmitters. Scanners may work. Regardless, do the best you can. If
you are planning to participate and haven’t already notified me,
please let me know so I can notify DEC how many stations will
participate. Finally, here is the data sheet sent by DEC to help log
any “hits” you might get. If you get any “hits”, please send
info to me no later than the following day.

Update:
The bats will tentatively be released around 2015 hrs. tomorrow April
22. IMPORTANT: the transmitters will be using CW, not FM as previously
thought. (This is completely my fault as I assumed 2m band to be FM)
Anyway, please change your mode to CW. I’m hopeful that we will get
some “hits”, especially from the folks to the South. Ashley Meyer,
the DEC representative, has agreed to do a debrief/presentation on
Monday, May 5 at 1915 hrs. I will be sending out a Zoom link a few days
prior.

Thank you all for your interest in this project.

‘73
Mark KD2RJP

All the DEC is looking for is your location when a signal is heard; and
the serial number of the transmitter. Send any reports to Mark at
kd2rjp(at)arrl.net

Vry 73 de
John
K2QY

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

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:

WNML 1670:

WMDM 1690:

KCNZ 1650:

KCJJ 1630:

KBGG 1700:

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

Dan asks: “What is your longest DX?”

29 Replies

Many thanks to SWLing Post contributor, Dan Greenall, who writes:

What is your longest DX (from transmitter to receiver)?

Assuming we are limiting the discussion to planet Earth, Perth, Australia would be represent one of the farthest land based locations to hear at 18145 km or 11275 miles as the crow flies from my receiving post in southern Ontario, Canada.

That would mean the ABC outlet that I received on 9610 kHz in the early 1970’s is the winner for me. Not far behind, however, would be tiny Amsterdam Island (part of the TAAF, Terres Australes et Antarctiques Francaises) in the Indian Ocean at 18031 km or 11204 miles. I was able to log marine radio FJY4 on 8690 kHz CW on a number of occasions and even managed to extract a PFC QSL direct from the station in 1973.

There are a number of distance calculators for this on the internet, such as Free Map Tools at
https://www.freemaptools.com/how-far-is-it-between.htm

Of course, the longest DX may not necessarily be the best. CKZN running 300 watts on 6160 kHz from St. John’s, Newfoundland from right here in Canada was harder to hear than the ABC in Perth, Australia!

Who can top this distance? What is your longest DX? Please comment!

Guest Post: 10 Meter Beacon DXing

16 Replies

Many thanks to SWLing Post contributor, Walter Salmaniw, who shares the following guest post:

10 Meter Beacon DXing

by Walter Salmaniw, Masset, BC

My hobby of radio listening has evolved over the years.  Beginning with crystal radios as a child in the 60s, I’ve migrated through SWLing with numerous rigs including the kings of valve technology, like the Collins R390A and Racal RA17, and then on to high end mil-spec solid state rigs:  Racals, Harris, Ten-Tec, and my all-time favourite, the Rockwell-Collins HF-2050 receiver.   Unfortunately, broadcast band stations, especially transmitting to North America, have dwindled over the years, and my favourite Pacific stations also disappeared:  120 and 90 meter Indonesians, the 60 meter AIR network, and the numerous PNG stations.  Well, what’s one to do?

About 10 years ago, I switched over to MW DXing, and especially trans-Pacific and trans-Atlantic DX.  My cottage near Masset, BC is the ideal location for such DXing, as I have an ocean beach location, the room for some great antennas, and very low noise in the area.  This has produced some incredible DX, and I’ve been honoured with visits by some pretty eminent DXers, including Victor Goonetilleke from Sri Lanka, Mauno Ritola from Norway, Vlad Titarev from Ukraine, as well as our own experts in DXing from Victoria and the Pacific North-West of the US.

MW DXing is great, but that involves DXing primarily during the night time and early morning hours.  What to do with the rest of the day?  Well, with the rising sunspot counts and heading toward the peak of the next solar cycle, why not look at 10 meters?  About 2 years ago, with a lot of help from the local DX geniuses, I was able to remote my set-up in Masset, and DX even when at home in Victoria, BC.  10 meters has consistently remained open almost every afternoon.  Now, I’m not a ham, and at this point, have no interest in obtaining my ham license.  However, I noted a lot of beacon activity on 10 meters.

I’ve dabbled in LW NDB DX, which can be a lot of fun.  Why not do something similar on the higher frequencies?   Not being a ham, I needed some help with decoding the beacons.  Thankfully, one can often see the CW and it’s slow enough to read in many cases.  Being a bit too lazy for that exercise, though, I’ve tried several software solutions to use with my KiwiSDR and Perseus SDR in Masset.  Fldigi is probably best known, and works fairly well.  Another program I use is MixW, which I’ve always liked for SSTV reception.  Another is CW Decoder.   None, however, get anywhere close to how well CW Skimmer works.  It’s an awesome program, albeit a pricey one.  I’m still in the test phase, but will likely go ahead and fork over the $75 to purchase this.  It will even take control of my Perseus receiver and decode 192 kHz worth of spectrum.  Wow!

     Here’s an example of what the band looked like last weekend:

There happened to have been a world-wide CW DX competition, but nonetheless, there were literally hundreds of CW signals to be decoded!  Now, for me, however, I was more interested in the Beacon region of 10 M which is roughly between 28150 and 28300 kHz.  I’ve found CW Skimmer to be a perfect tool to decode the beacons.  Not only is it very accurate, but one can also easily see the CW signal with the dahs and dits on the screen and a continual readout of the messages.  Most of these beacons run 5 or 10 W, and all are run by amateurs.  Where to find information about who they belong to?  That’s easy as well.  WI5V.net has a great 10 M beacon list at https://wi5v.net/beacon-list-table-version/ .  That’s my go to, but I also have DL8WX.de’s beacon list on my laptop, giving even more information, like contact e-mails, etc.  He’s found at:  http://www.dl8wx.de/BAKE_KW.HTM

What type of antenna do I use?  Well, none of mine are 10 M antennas at all.  Most are, in fact, for DXing trans-oceanic MW DX!  Still, they seem to work quite well.  My go-to has been a DKAZ antenna aimed 290 degrees.  Now, that’s 180 deg to where most of my Beacon activity comes from.  How come?  Well, Nick Hall-Patch, MW DXer extraordinaire, used his ENZEC antenna prediction program to see how the DKAZ works on 28 MHz, and sure enough, it’s opposite to MW DX.  On the lower band, it’s best aimed 290 deg, but 180 deg opposite on 28 MHz!   Who would have guessed that one?  In any case, the next time I’m in Masset, I plan on putting up a simple vertical for 10 meters, seeing that solar max is still a year or two away, so there’s plenty of time for some fun DX!

Here’s what I’ve heard with a few afternoons of listening.  My best catch has been Darwin, Australia!

28207   N4XRO  1924  CW  5 watt beacon heard with a bit of a buzzy signal best deciphered on my 110 deg DKAZ….  17/Oct/2022 (Salmaniw, Masset, BC)

28236.5   W0KIZ  1933  CW  Another well heard beacon this morning giving ID in CW along with location.  Also very strong at 23:11 recheck.  Almost a barn burner!  Not bad for 5 watts! 17/Oct/2022  (Salmaniw, Masset, BC)

28244   WA6APQ  1934  CW  Much stronger, and it shows with their 30 watts output, with slow CW giving callsign, then location. Very strong when rechecking at 23:05 UTC.  Frequency is actually a little lower than listed.  Actually measuring 28243.942 kHz.  17/Oct/2022  (Salmaniw, Masset, BC)

28287   WI6J  1949  CW  Poor reception, but with same format giving ID and location.    17/Oct/2022  (Salmaniw, Masset, BC)

28250   K0HTF  2248  CW  Fairly good copy of this beacon away from the coast now in Iowa.  Only giving callsign/B.  Tom ‘Doc’ Gruis

replyed to my email confirming he’s feeding 20 Watts from an Old President radio and feeding an AR-10 antenna.  Thanks, Doc!  17/Oct/2022  (Salmaniw, Masset, BC)

28248.3   NJ5T  2258  CW  A relatively difficult catch, but I decoded the J5 part of his call, as well as ‘dipole’.   17/Oct/2022 (Salmaniw, Masset, BC)

28215   KA9SZX  1954  CW  Beacon quite well heard from Masset.  Most of my 10 meter beacon loggings have been a more N/S axis, but this one is coming in nicely in our early afternoon.  Callsign and power listed as 3 W, along with his email address. 5/Nov/2022  (Salmaniw, Masset, BC)

28218   AC0KC  2035  CW  Despite being listed as on 28218.5, he’s actually on the even channel at fair level into Masset.  Solar powered and only 3W, into a Bazooka antenna (what’s that?). Call sign repeated.  5/Nov/2022  (Salmaniw, Masset, BC)

28220   AA8HS  2123  CW  Despite listed as 30 Hz higher, I’m hearing them on the even channel with repeated IDs.  Fair level. Antenna listed is a vertical J-Pole.  5/Nov/2022  (Salmaniw, Masset, BC)

28230.3   W2MQO  2125  CW  Strong reception with call sign as W2MQ0/B repeated twice, then tones, and cycle repeats.  Into a Bazooka Antenna.  5/Nov/2022  (Salmaniw, Masset, BC)

28203   KG8C0  2132  CW  Another strong beacon with call sign, and prolonged tone, and repeat.  5/Nov/2022  (Salmaniw, Masset, BC)

28203.5   K6LL  2134  CW  Strong signal also from California, ID’ing as K6LLL/BCN, and giving location and QSL info.    5/Nov/2022 (Salmaniw, Masset, BC)

28193   VE4ARM  1827  CW  Excellent reception of my first 10 meter Canadian Beacon.  Run by the Austin, MD Amateur Radio Museum, as outlined in their beacon text.  6/Nov/2022  (Salmaniw, Masset, BC)

28284.8   N9TNY  2226  CW  Another new one for me from Illinois.  Not a particularly great afternoon, but nonetheless, a number of CW Beacons on 10 meters are visible/audible.  Callsign is given, then PSE RST.  Not sure what that means?  Wiki tells me that this is like SIO or SINPO code.  Stands for Readability-Signal Strength-Tone.  Hmm.  28/Nov/2022  (Salmaniw, Masset, BC)

28297   NS9RC  2237  CW  Another Illinois Beacon audible.  This one is weak, but fiddling with the KiwiSDR AGC settings, makes for a much better decode (mostly raising the CW Threshold (marked Thresh CW in the AGC section).  Near 100% correct decode now. Chicago is sent along with call sign.    28/Nov/2022 (Salmaniw, Masset, BC)

28287   WI6J  2240  CW  Strong signal from this Californian, and heard before.  VVV VI6J/B Bakersfield CA DM 5     28/Nov/2022 (Salmaniw, Masset, BC)

28254.5   K4JEE  2243  CW  Good copy with VVV DE K4JEE/B K4JEE/B K4JEE/B LOUISVILLE, KY  28/Nov/2022  (Salmaniw, Masset, BC)

28236.5   W0KIZ  2300  CW  Always one of the strongest beacons on 10 meters, and not disappointing this afternoon.  VVV W0KIZ/B DENVER, COLORADO . 5 WATTS, So does he mean 5 or 0.5 Watts? Presumably 5 Watts.  28/Nov/2022  (Salmaniw, Masset, BC)

28206.5   KA7TXS/B  2303  CW  Nice reception with VVV DE KA7TXS/B DM22 Listed in dl8wx.de website, but not the primary one I use (wi5v.net Beacon Website).  28/Nov/2022  (Salmaniw, Masset, BC)

28209   N5TIT/B  2315  CW  Fair reception with VVV DE N5TIT/B EM1UPX, or something similar.  28/Nov/2022  (Salmaniw, Masset, BC)

28211.8   AC7GZ  2321  CW  Good reception for only 3 W with VVV DE AC7GZ AC7GZ AC7GZ DM3BI.    The latter is the ham grid square, near Mesa, AZ.  28/Nov/2022  (Salmaniw, Masset, BC)

28232.3   W7SWL  2323  CW  I like the callsign!  Fair reception with VV DE W7SWL TUCSON AZ DM42  The band is fading fast.  Fascinating that the best antenna for 10 m Beacon reception today is my 290 deg DKAZ (and not the 110 deg DKAZ).  Not sure why! 28/Nov/2022  (Salmaniw, Masset, BC)

28206.5   N4SO  2231  CW  Very weak, but really picked up just now.  DE N4SO/B repeated. A fine catch!    30/Nov/2022  (Salmaniw, Masset, BC)

28212.8   AC7GZ  2253  CW  Very strong reception with VVV DE AC7GZ AC7GZ AC7GZ DM43BI  30/Nov/2022  (Salmaniw, Masset, BC)

28209.5   N2UHC  2300  CW  Tough copy, but bits of STPAUL decoded. as well as N2UHC/B.    30/Nov/2022  (Salmaniw, Masset, BC)

28254.5   K4JEE  2308  CW  Strong reception with ID and location.  Deep fades, as well, though.  30/Nov/2022  (Salmaniw, Masset, BC)

28255.8   WI5V  2310  CW  Fair reception with occasional good fade-ups with WI5V/B repeated.  30/Nov/2022  (Salmaniw, Masset, BC)

28175.5   VE3BKM  2034  CW  Hearing an unlisted beacon.  VE3BKM/BCN repeated, often at strong level.  A new one for me! 5/Dec/2022  (Salmaniw, Masset, BC)

28168   VA3KAH  2040  CW  I have no idea where this island is located, so had to look it up.  Fair reception with VV DE VA3DAH/B It’s located to the north of Lake Simcoe in southern Ontario. 5/Dec/2022  (Salmaniw, Masset, BC)

28145   DL2WB  2048  CW  A highly tentative logging.  All I hear is the occasional tone for several seconds, then off.  Nothing else listed on this frequency, so no idea!  5/Dec/2022  (Salmaniw, Masset, BC)

28203   KG8CO  2055  CW  Very strong signal with repeated KG8CO/BT 5/Dec/2022  (Salmaniw, Masset, BC)

28203.5   K6LLL  2058  CW  Weak reception with VVV K6LLL/BC Grid Square coordinates, and PSE QSL TNX DE K6LL/BCN.  5/Dec/2022 (Salmaniw, Masset, BC)

28206.3   KA7TXS  2100  CW  Strong reception, although a bit of a congested part of the band making decodes a tad difficult. Not listed on my main source (WI5V Beacon website), but it is on the dl8wx.de website.  5/Dec/2022  (Salmaniw, Masset, BC)

28208   WD5GLO  2126  CW  Fair copy with WD5GLO/B repeated 3 times and OK OK  5/Dec/2022  (Salmaniw, Masset, BC)

28209.1   N5TIT  2130  CW  Poor reception this afternoon, but making out the call-sign.  VVV DE N5TIT/B.  100 Hz higher than listed.    5/Dec/2022  (Salmaniw, Masset, BC)

28209.5   N2UHC  2133  CW  Poor reception, but seeing his callsign. Fades up to quite good at times.  N2UHC/B EM27JM N2UHC/B ST PAUL KS.  5/Dec/2022  (Salmaniw, Masset, BC)

28212.1   AC7GZ  2140  CW  A regular visitor to Masset.  Fair to good this afternoon with VVV DE AC7GZ DM43BI  5/Dec/2022 (Salmaniw, Masset, BC)

28215   KA9SZX  2142  CW  A slower rate beacon at good reception:  VVVV KA9SZX KA9SZX KA9SZX BCN MACOMB IL PWR 3W GRID EN40PK EMAIL KA9SZXWAYAHOO.COM  Now that’s a full information beacon! 5/Dec/2022  (Salmaniw, Masset, BC)

28217.7   K4PAR  2152  CW  Very weak, but fully decodable with VV DE K4PAR/B.  Listed as from the Piedmont ARC and 25 W.  Just barely audible.  5/Dec/2022  (Salmaniw, Masset, BC)

28220.15   AA8HS  2155  CW  Measuring below their listed 28.2203 frequency.  Weak but in the clear.  5/Dec/2022  (Salmaniw, Masset, BC)

28232.3   W7SWL  2206  CW  Now that’s a call-sign!  He wasn’t there a few minutes ago, but noticed a very powerful beacon.  VVV DE W7SWL W7SWL TUCSON AZ DM42 and repeated.    5/Dec/2022 (Salmaniw, Masset, BC)

28254.5   K4JEE  2220  CW  Another beacon I recognize from previous sessions.  Fair to good reception this afternoon with VVV DE K4JEE/B K4JEE/B K4JEE/B LOUISVILLE, KU EM78.  5/Dec/2022 (Salmaniw, Masset, BC)

28255.8   WI5V  2226  CW  Weak reception, with some AM QRM.  VVV DE WI5V/B   5/Dec/2022  (Salmaniw, Masset, BC)

28278.5   WA4OTD  2228  CW  Weak, but in the clear with callsign and location.    5/Dec/2022  (Salmaniw, Masset, BC)

28280   K5AB  2231  CW  Strong reception with DE K5AB EM01BEACON, repeated, then CENTRAL TEXAS  5/Dec/2022  (Salmaniw, Masset, BC)

28281.1   W8EH  2234  CW  100 Hz above their listed frequency at fair level with callsign and grid square reference.    5/Dec/2022 (Salmaniw, Masset, BC)

28284.8   N9TNY  2237  CW  Strong reception with callsign and grid square reference.  5/Dec/2022  (Salmaniw, Masset, BC)

28236.5   W0KIZ  2243  CW  Again, a beacon not there a few minutes ago, but really burning up the receiver with repeated VVV DE W0KIZ/B DENVER COLORADO 5 WATTS.  5/Dec/2022  (Salmaniw, Masset, BC)

28240   W8EDU/B  2223  CW  Weak, but readable.  For only a watt, I’m impressed!  Giving callsign and grid square location.  Found them on the dl8wx.de beacon website.  Location and operator is the Case Western Reserve University amateur radio club. 8/Dec/2022  (Salmaniw, Masset, BC)

28252.5   WD8INF  2227  CW  Good reception with callsign and grid square locatioon (EM79).  8/Dec/2022  (Salmaniw, Masset, BC)

28258.5   AC5JM  2229  CW  Good copy with callsign and OK repeated. 8/Dec/2022  (Salmaniw, Masset, BC)

28277.56   WA4OTD  2232  CW  Fair copy.  Listed in the WI5V beacon website on 28.2788, so a bit lower in reality.  Giving callsign, grid square, and CARMEL  8/Dec/2022  (Salmaniw, Masset, BC)

28281.1   W8EH  2235  CW  Good reception with callsign and grid square (EM79).  Clearly, Ohio is coming in well this afternoon. Normally I’m hearing AC7AV on or near this channel (Green Acres, WA).    8/Dec/2022  (Salmaniw, Masset, BC)

28284.8   N9TNY  2237  CW  Strong signal with VVV DE N9TNY/B EN51 PSE RST.  8/Dec/2022  (Salmaniw, Masset, BC)

28271   W4ZZK  2245  CW  A very weak signal heard while monitoring another very adjacent signal.  , giving the callsign/B.  CW Skimmer comes through again!  8/Dec/2022  (Salmaniw, Masset, BC)

28290.8   K5TLJ  2302  CW  Weak reception, but able to copy AR AR AR DE K5TLJ/B K5TLJ/B K5TLJ/B AR   Band is quickly fading, so looks like this is the top frequency beacon I can hear now. 8/Dec/2022  (Salmaniw, Masset, BC)

28250   K5AB  2341  CW  A this late hour, very little propagating in the 10M Beacon band.  Nonetheless, good reception from this high power beacon with DE D5AB EM01BEACON DE D5AB CENTRAL TEXAS.    14/Dec/2022  (Salmaniw, Masset, BC)

28268.334   VK8VF  2344  CW  My first Australian beacon!   Very weak, but the call sign is being decoded by CW Skimmer.  Not even visible on the waterfall.  334 Hz high compared to the listed 28.268 on the WI5V Beacon website.    14/Dec/2022  (Salmaniw, Masset, BC)

28189   VE4TEN  2100  CW  Great reception this afternoon.  The band had many 10 M beacons, but unfortunately, I had other family matters today.  Still, nabbed this one, with an interesting call, and flea powered as well.    18/Dec/2022  (Salmaniw, Masset, BC)

28193    LU2DT  2355  CW  My surprise for the afternoon, and my first Argentinian beacon.  Fair reception.  Long, somewhat garbled tone, followed by VV DE LU2DT LU2DT GF12FA.  Distance approximately 12,432 kM with bearing 125 degrees!  19/Dec/2022 (Salmaniw, Masset, BC)

I hope that I’ve wetted your appetite into trying something, “completely different” in our radio monitoring hobby.  Who knows next what I’ll want to try!

Walter Salmaniw, Masset and Victoria, BC

Small Unidirectional Loop Antenna (SULA) Part 3: Questions & Answers

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Many thanks to SWLing Post contributor extraordinaire, 13dka, who brings us Part Two of a three part series about the new SULA homebrew antenna project. This first article describes this affordable antenna and demonstrates its unique reception properties. The second article focuses on construction notes. This third and final article will essentially be a Q&A about the SULA antenna. 

This wideband unidirectional antenna is an outstanding and innovative development for the portable DXer. I love the fact that it came to fruition via a collaboration between Grayhat and 13dka: two amazing gents and radio ambassadors on our SWLing.net discussion board and here on the SWLing Post. So many thanks to both of them!

Please enjoy and share Part 3:

Part 3: SULA Q&A

by 13dka

Q: Where can I ask questions, discuss all aspects of the the SULA or collaborate in its further development?

A: There is a thread dedicated to the SULA in the new SWLing.com message board: https://swling.net/viewtopic.php?t=55

Q: Since the antenna is “lossy”, what’s the point of having a “beam”?

A: The answer is once again “SNR”: First off, remember that the LNA is there to make up for most of the losses. Secondly, this is all about the noise pickup, 20dB less gain/more losses outside the main lobe means also a reduction of atmospheric/cosmic/whatnot QRN and of course everything manmade from all these sides. The wide horizontal lobe is more or less one hemisphere horizontally, but the flat-ish vertical pattern makes that only a slice of it. In other words, there will be less QRN and QRM pickup from the back and the top. The idea is that the SNR will ideally increase more than the preamp’s noise figure will cost and it often sounds like this is what actually happens. Of course it’s also nice that you can turn an unwanted signal down using the more or less pronounced notch in the backside pattern up to 21 MHz – also very helpful for direction finding.

Q: Do I need a rotor?

A: It depends. If you are one of the lucky few still having a low-QRM-environment at home and you want to put it in the backyard, you really may want to be able to turn it remotely. If you’re using it portable you can simply rotate the mast manually. If you have local QRM or can’t mount it very far away from your or other houses, you may want to rotate the back of the antenna towards that source, leave it at that position forever and enjoy what’s coming in on the pretty wide main lobe of the antenna. The horizontal lobe covers more or less half of the horizon, depending on your stations of interest and location you could get away with never turning the antenna at all.

Q: Is it better than the XYZ loop?

A: Hey, that’s exactly what I wanted to ask you! 🙂 Even though the SULA is very similar in appearance and performance to a good SML working in ideal (ground conductivity) conditions, the SULA is a pretty different animal with a different behavior: Regular small loops, besides being bidirectional, can lose quite a bit of their low angle sensitivity over “poor” ground while the SULA is supposed to be retaining its properties better over any type of ground. Also, while many SMLs are tuned for VLF through the lower portion of the shortwave, the SULA complements those with quite uniform (good) properties up to 30 MHz and beyond.

Q: I have an end-fed random wire or dipole strung up from the house to a tree etc. – can the SULA beat that?

A: That’s quite possible. To get low takeoff angles from horizontal wire antennas you need to string them up at least 1/2 wavelength high, that’s 20m/66ft on 40/41m, 10m/33ft on 20m and so on. If you can’t do that, the SULA may be your ticket to listen farther beyond the horizon. Also, wire antennas are often strung up to match space restrictions or avoid QRM vectors and that way you may end up with some directionality in directions you don’t want, or no directionality at all when the wire is too low. Another noteworthy point is the ground: For most horizontal antennas, better ground means a considerable higher takeoff angle so the dipole needs even more height for low angles. The SULA’s takeoff angle benefits a little from the better ground and only gets a little worse over poor ground.

Q: Do I really need an LNA?

A: I hope so? Of course it depends… if you are going to try this antenna in a very noisy environment, the LNA may have little to no benefit. The noise is limiting your “radio horizon” to very loud signals anyway and for those you may not need an LNA, ever. On the other hand, the antenna is very lossy and in a quiet environment where noise is not an issue at all, weak signals may drop below the sensitivity threshold of your receiver without the LNA. The less noise you have, the more you’ll be able to benefit from an LNA. You will also need one when your radio isn’t all that sensitive, similar to the requirements to run a YouLoop. Andrew kept the loop impedance as constant as possible in order to allow any low impedance coax preamp to work behind the Balun. Any LNA with 20dB of gain should do, as per usual, better stuff may bring better results.

Among the sparse offers for decent shortwave LNAs, the NooElec LANA HF seems to be the only decent LNA sold via Amazon. It’s comparatively low-cost and unlike the other offers on Amazon, ready to be powered via Bias-T or even via Micro-USB and therefore happy with 5V. Since I also had the balun from the same company I could simply connect that all with a couple of these cute little SMA plumbing bits and it worked. The downside is its unknown but perceivably low resilience against intermodulation (low 3rd-order intercept point), this is usually not a problem with such a small loop but it can be in the presence of nearby transmitters.

If you do have nearby transmitters and don’t mind sourcing an LNA from Europe, Andrew recently pointed me to preamps from here. They offer a moderately priced preamp with a 2N5109 transistor (based on the W7IUV design) for a high IP3 value and low noise, which is also available in PCB-only and fully assembled versions including a compartment. They also offer Bias-T boxes.

Q: What is special/different about this antenna? There are already very similar designs!

A: It’s supposed to be simpler and more compact/portable, and it seems to deliver more consistent results over the entire coverage range in different usage environments than similar designs. The SULA was designed to be made with things that are particularly easy to obtain, or which were already obtained — many of us SWLs have some of that Nooelec stuff in our drawer anyway, even when (or because) we’re not habitual antenna builders and balun winders. Now making a better balun and buying a better preamp is not hard and could even bring better results but the point is that you don’t have to. In summary, this is not meant to be a miracle antenna, just number of compromises re-arranged to create a particularly uncomplicated, small, unidirectional loop antenna that aims for DX, for apartment dwellers and DX nomads like me.