Wednesday, July 24, 2019

Summer (blog) Vacation

I'm still here. New blog articles are slow to appear because I am very busy with antenna and tower projects, 6 meter DXing and a large number of non-ham summer fun stuff and chores. I thought I would fill the blogging gap with a progress report of sorts so that regular readers don't think I've vanished. I haven't. Regular blogging will resume, eventually.

To give you an idea of what I am up to I've listed the most important projects below. From this you will get an idea how busy I am. All will be written up in future articles as each project is completed and I have the time. But right now the weather is too good to waste. I have not provided links to articles which discuss these projects so if interested try the search box.
  • The 80 meter vertical yagi is near completion. The parasitic elements are tuned and the switching system is operational, as is the control head in the shack. What's missing is the control box containing the switching matrix, cable interconnections and switchable L-networks. It is partially built and I have all the parts.
  • Options and specs for the mast and rotation system for the new 140' tower have been discussed with my local machine shop and I should have the fabrication complete in the first half of August. I will be using my spare prop pitch motor as the rotator.
  • One boom left to be built for the 2 × 5-element stacks of 20 and 15 meter yagis. That one requires machining of a 20' long pipe the machinist can't handle in his shop. But it'll get done one way or another.
  • I have fabricated 2 sets of 5 element-to-boom clamps for those yagis. The rest are awaiting an order of fasteners to make drilling templates.
  • All the aluminum for the 20 yagi elements (4 × 5) is on hand and the bulk of the machining is complete. Once that is done the sections will be joined and yagi construction and testing should begin around mid-August. Elements have been scaled in software for the taper schedules that I settled on.
  • Design of the elements for a forthcoming full size 40 meter yagi is proceeding. I hope to at least get one complete element in the air as a dipole for testing over the winter to see how it performs electrically and mechanically.
  • Tower maintenance is ongoing. This includes patching surface rust, vertical alignment and checking of all hardware. Repair of malfunctioning antenna requires getting them down using the same tram line used to put them up them.
Reading the list is fatiguing enough, yet these are things I have to get done in the next few months.

Haying on my land should be complete this week and I will have more freedom to work on towers and antennas. This includes malfunctioning yagis that need to come down for repair or to be moved to a different tower.

I hope the weather is as good where you are as it is here and that you, too, are making progress on your station projects. Soon enough the weather will turn cool and the race will be on to complete work before winter settles in. Then I will have the pleasure of cold weather projects such as low-noise receive antennas and shack equipment. It'll be a while yet before I can truly relax.

Tuesday, July 9, 2019

Working Japan on 6 Meters

From my start on 6 meters in the mid-1970s, to the tremendous solar maximum of 1989-1990 and into the modern era of FT8 it is interesting that I had not achieved WAC (Worked All Continents) on the magic band. The one continent that confounded me was Asia. I came very close in 1989, eking out several partial CW QSOs with Japan. That was my sole shot since almost all of west Asia, like most of Europe, did not have a 6 meter band at the time.

With FT8 prospects improved, despite the lack of sunspots. Sporadic E openings to Japan and the Far East from eastern North America have been known about for a long time but due to their fleeting nature have only rewarded the most dedicated 6 meter aficionados both here and there. These openings are easier to catch with FT8 since all activity is captured by the software. This is what I've coined the discovery problem which FT8 solves so very well.

Historically it is known that the probability of an opening between Japan and northeastern North America peaks in the last week in June between 2130Z and 2300Z, our late afternoon and early morning in Japan. In fact the times between this daily window and their sunrise and our sunset are nearly equal. Although that may be nothing more than a coincidence it is nonetheless interesting.

To my chagrin I missed a fantastic opening in late June last year, the first year that I and most of the 6 meter community were on FT8. It was dinnertime and by the time I discovered what had been occurring the opening was ending. Sitting in front of the rig every day during the propagation window is not realistic, nor very enticing.

This year I was not so complacent. I really wanted a QSO with Asia, and openings to the Middle East have so far yielded no QSO. So I monitored, watched and waited for another opportunity to work Japan.

Statistically speaking I would likely have one or two chances, each lasting no more than 15 minutes. This would be terribly daunting were it not that it is early evening when I am more likely to be in the house. But this time I would have to pay close attention to activity.

During the second half of June there was no workable opening to Japan from this QTH. Others to the south, west and east had better luck. Other than a couple of decodes of very weak signals nothing was workable here in FN24. That changed in July.

The first opening arrived on July 2. Unfortunately it was only JA7QVI who was sporadically copied over a period of 10 minutes. Several other likely but very weak signals that appeared on the spectrogram did not decode. I called him without any luck. This isn't surprising since he is a big gun who typically runs QRO and his weak received signal boded ill for my 150 watts.

Success had to wait two more days. On July 4 signals were being reported by others in this part of the continent as early as 2200Z. I did not hear any QSOs being completed but clearly something was brewing. A strong opening to OX was on the wane at that time and the Nunavut beacon VY0SNO/B was widely heard. It was a challenge to monitor the band while cooking the evening meal! Happily the real fireworks waited until meal preparation was completed.

When signals began decoding I noticed that more were stations calling KL7HBK. Alaska's bearing is only 10° west of the Japan path but I never did copy him.

JE1BMJ was calling CQ NA but I couldn't get through to him as he faded in and out for several minutes. None of the other stations heard were decoded more than twice.

They say that patience is a virtue, so I made a sacrifice by eating my dinner in the shack. I watched and hoped for signals to grow stronger. Of course I was not quite that patient so I filled the silence with my own CQ JA.

As you can see in the screen shot that eventually signals did rise. A few decibels made all the difference. First in the log was JH1IFS. Then for a few short minutes I was the object of a small pile-up. I worked just 4 stations before the opening faded, but even one was enough to leave me delighted. During the fade I made a couple of partial QSOs as signals briefly rose out of the noise. Within 10 minutes they were gone for good.

It is interesting that I never heard the KL7 the JAs were calling and big guns only a few hundred kilometers from me appeared to work nothing in this opening. This is a great example of the spotlight nature of 6 meter openings. The spotlight narrows as the path length increases. All those points of intense E-layer ionization must line up in space as well as time to make the QSO possible. That's part of the attraction, working with what nature tosses our way to put the magic in the magic band.

Notice that every Japanese station calling me skipped message #1 in the standard FT8 sequence and used RR73 rather than separate RRR and 73 messages. That is an excellent practice for fleeting openings. They can be so short that the 30 seconds saved is critical to success. It also allows for more QSOs to be made by everyone during the opening.

I suspect the Japanese operators are acutely aware of this since almost all their DX QSOs on 6 meters are on paths of this type. Once you miss out on some juicy DX using the standard (and longest possible) message sequence you quickly learn. Exchange of grid squares is nice but is not necessary. The minimum required information for a valid QSO is call sign, report and confirmation of both.

Afterward I sat back and contemplated this achievement. It was one more of persistence than any particular skill. Sometimes that's all it takes. Just as in contests the one under-appreciated difference between the winners and losers is BIC: butt-in-chair. That was perhaps the most important factor that put these rare QSO into my log.

Technically I now have WAC worked on 6 meters. However I restarted my DXCC count when I returned to the air in 2013, on which basis I still need Oceania. My best shot for that is a Sporadic E openings to KH6. From here these are rare but certainly workable, perhaps no worse than Japan but with fewer active 6 meter operators. I've had a few false alarms since with US call sign portability the only KH6/AH6/WH6 stations I've heard were within the continental US. However I know that some in this region have worked Hawaii this season.

Returning to the topic of spotlight openings, these openings to Japan, Hawaii and other distant locales cannot be so unique. There must be many more similar openings to the unpopulated or lightly populated expanses of the Pacific Ocean and northwest Asia. Without active stations those openings remain undiscovered. Certainly there are other islands and UA0 is hardly empty, but the population density is low and the ham density is lower still. We need a confluence of rare conditions and a dedicated group of hams attuned to the nature of 6 meter propagation.

Calling CQ into a silent band is not a bad strategy even though there is rarely a reply. Somebody has to CQ, so why not you? It may be a rare occurrence but every so often a strong DX signal will answer. Sporadic E DX propagation has existed for many millions of years and will continue long after amateur radio is just a memory. It's up to us to appreciate this gift and put it to good use.