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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.

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!

“The emphasis is fun. The hope is that it will attract new people to electronic design, measurement and experimentation. Hopefully, this site stimulates interest in QRP homebrew electronics.”

That's how Todd Gale, VE7BPO, described his website. Up until this past weekend, Todd site was one of the Web's premier sources of inspiration, accumulated homebrew knowledge and hands-on experimental wisdom. I was shocked to receive an e-mail from Todd explaining that the site would be taken down because of continued  bandwidth / network struggles with his one and only choice of providers. It truly was sad news for myself and the thousands that regularly visit his site for guidance. However, all is not lost as Todd went on to say:

"....I will convert all the site files into pdf files and stick them on a download site sometime in the future. I may re-emerge with a small-scale site or blog at some point, but don't really know for sure."

Happily, today Todd has informed me that he will indeed begin a new POPCORN QRP  blog in which he hopes to update with his benchwork descriptions that we have all come to enjoy.

I have listed Todd's blog site on My Blog List to the right but you may prefer to set your bookmarks for his site. Don't expect too much until later in the month as he is still working his way up the blogger's learning curve....hopefully we will see him back soon. Best of luck with your new endeavour...and, like the original website, I'm sure it will be great!

Courtesy: VE7BPO

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 cost 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 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 (567) 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 tradition..."if your antenna stayed up all winter, it wasn't big enough". I just can't win.

ZVR - 368 Vancouver -  Middle Marker Rnwy 08R - reported as far as California

Now that CLE186 has come and gone, worldwide results will soon be posted by e-mail (to all those submitting reports) as well as to the CLE website. CLE organizer and data-cruncher Brian Keyte (G3SIA), indicates that 50 logs (and over 2,000 reports) have been submitted, including two first-timers - Graham (VE3GTC) near Ottawa, ON and Hans (BX2ABT) in Taiwan. It's always great to see new activity, especially on LF!

As is usually the case with CLE's, propagation conditions begin to deteriorate shortly after the announcement of the upcoming event. By the weekend's arrival, conditions are usually much worse than earlier in the week and such was the case once again! In North America, lightning activity and mediocre propagation dominated the three-night event, with the consensus of opinion giving the nod to Saturday night and early Sunday morning as being the best period.

Courtesy: http://www.lightningmaps.org/

Here on Mayne Island, Friday night was pretty much a wash and only the stronger signals made it through the din and into the log. A twilight check on Saturday evening indicated improving propagation and less lightning, renewing optimism that the entire weekend would not be a wipeout.


Since purchasing the Perseus SDR earlier this year, I have been using it exclusively for the past few CLE's. I have been exploiting one of it's main features....the ability to record the entire band overnight and then tune through the band the next day, as in real time. I no longer had to prop my eyelids open until 0100 or later, or to leave a sound sleep to journey out to a cold shack to hunt the pre-sunrise band for anything new....yes, Perseus has made it possible to DX while I sleep!

Now the very concept of this horrifies many of the 'purists' and I myself held-out for several years before venturing over to the darkside...but...embracing new technology along with its associated new learning is what is important. If I get to sleep-in because of it, even better!

So....that's the way it is supposed to work, but due to operator error, Perseus failed to launch on Saturday night, and the best conditions of the CLE were missed altogether. Having seen the error in my ways, the perils of Perseus will, hopefully, not strike again!

Conditions on Sunday night were noisy once again, although not as bad as Friday, and the following log was gathered after parsing through my overnight recordings.


I have, over the years, logged all of these beacons before, except for one..."OKT" in Yoakum, Texas...new catches are always nice and are harder to find  it seems. The Google Map's 'street view' shows what appears to be a nice top-loaded "T" antenna at OKT:

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

My CLE186 beacons - Courtesy: https://www.google.ca/maps/

It was nice to salvage Sunday night but I'm still a little bummed about missing the best night of the weekend...at least I had a good night's sleep.

The Mini-Whip at University of Twente's (Netherlands) Remote Receiver

I think many hams believe that they need big antennas and lots of space to operate on 630m or even to listen on the band. I can assure you that big antennas are definitely not needed to listen or for that matter, even to transmit effectively.

You might be surprised at just how well you can hear on 630m using one of your low band antennas, such as an 80m or 40m dipole. Best results will be had with the coaxial feed's shield lifted from ground and connected to the center pin. This, in effect, allows your dipole to act as a top-loaded 'T', with the coaxial feedline now acting as the vertical element and the dipole section as a capacitive tophat. With a few ground radials, such an antenna can even be used for transmitting, if suitably resonated, but that's another topic altogether. Even untuned, this system will allow you to receive suitably on 630m providing your location is not inundated with high noise levels. High noise levels can often be overcome by using loops, either resonated or broadband. Loops can be very effective at nulling noise, particularly if it is coming from one direction, and vastly improving LF receive-capabilities.

Another popular solution and one that can be quite effective at lowering noise levels and improving overall signal-to-noise is the use of a short active (amplified) whip antenna. One very popular and proven design is that of Roeloff Bakker, PAØRDT. His simple-to-build active whip has been employed around the world and is being used by many LF'rs for dependable reception on the NDB band as well as on 630m. Roeloff himself operates from a noisy urban area yet manages to hear amazingly well on LF and MF with this simple antenna. Unlike a much larger wire antenna or large loop, the small active whip can be easily positioned in the quietest part of your backyard or rooftop. Often just moving such an antenna a few feet one way or the other can make a huge change in the noise level if you are operating from a typical city or suburb location....the PAØRDT whip may be all that you really need for long-term, reliable LF reception.

Courtesy: PAØRDT

Common practice is to mount the PCB inside a small weather-sealed PVC pipe and erect it atop a mast, after taking the time to "sniff-out" the quietest location for its placement.

Courtesy: http://www.leeszuba.com/projects/

With very few parts needed, the whip can be built for just a few dollars...even less with a good junkbox and the needed transistors.

Courtesy: http://www.leeszuba.com/

You can read Roeloff's own information on construction of the active whip here, with additional information here.

I even see the parts and PCB available on e-bay. As well, Roeloff himself, can provide finished units ready to mount in the air.

Courtesy: http://countingradios.blogspot.ca/2014_01_01_archive.html

There are plenty of informative Mini Whip articles and construction stories on the web should you wish to learn more:

• Fundamentals of the Mini Whip  by PA3FWM

• A Compact Active Wide-Band Receiving Antenna  by G3GRO

•  PAØRDT Mini Whip - Commercial & Homebrew Versions Tested  by GØKYA

• The PAØRDT Mini Whip  by DL1DBC 

• The Mini Whip Antenna  by Lee Szuba

If you're stuck with limited space for an LF-receive antenna, this may be just the answer!

I originally built what I called the "Tri-Tet-Ten" to  test out a long-held idea of actually working Europe on 10m, using just a single-tube tri-tet oscillator and a 40m crystal. I had no idea what amount of power might be obtained on 28MHz from a single 6L6 crystal-controlled oscillator, quadrupling from 40m to Ten. After building several configurations as well as trying five different tube types, I was pleasantly surprised to end up with almost five 'clean' watts of 10m RF on my 40m crystal's 4th harmonic! I suspected that the tone would be unusable but the tri-tet proved to be surprisingly good at isolating the oscillator from the output stage. Although chirpy, the signal is indeed usable and somewhat reminiscent of what so many 10m CW signals must have sounded like at one time.

Having completed the transmitter just in time for Cycle 24's hoped-for great 10m conditions, it turned out that only a couple of one-week periods over the past three winters where good enough to reach Europe. During the two "double-peaks" I worked many dozens of Europeans, all of them in response to my crystal-controlled CQ's, mostly on 28.042kHz.



Courtesy: http://www.noaa.gov/

Nobody was more excited than I, the first time I heard a reply from Europe....it was from G4RRA who, as fate would have it, recorded my signal on that early October morning.


There were a few mornings when I had long pileups and worked Europe for several hours, most of the time shaking my head in disbelief that such a simple transmitter could provide so much DX pleasure...but really of course, it was mostly the great performance of Ten....the "other magic band".





I really doubt that 10m will once again support European conditions good enough for my one-tuber but it's still fun to work the U.S. With Cycle 24 on the decline I was happy to see that F2 has returned to Ten once again and this week I sparked-up the tri-tet to enjoy the propagation.

My chirpy return to the band produced many enjoyable QSO's..... NG2T (NY), KD8IFJ (MI), K9DP (IN), KA2MLH (NY), W4NA (VA), N4OW (FL), K8NS (FL), N5AF (TX), WA5AFD (OK), K5TIA (TX), K9DX (IL) and VE3IKV/m, boldly travelling along the freeway at 120kph!

So....if you hear a chirpy CQ just a smidgen below 28.042, please.... give me a call!

Will I be lucky enough to squeeze out one last winter of tri-tet fun before having to move down to 15 or 20m? Time will tell....but somehow it won't be quite the same as riding that delicate 10m ether over the pole to Europe, on just one tube.