Monday, August 1, 2016

6 Meters: The Irritating Reality of the Magic Band

As the saying goes, 6 meters is the magic band. It's full of surprises since at one time or another it supports propagation by every propagation mode imaginable, and sometimes combinations of them:
  • F- layer during solar maximum
  • Sporadic E, especially around the solstices outside the tropics
  • Aurora, mostly in middle and high latitudes
  • Tropospheric, depending on weather systems
  • EME
  • Ground wave
Ever since 6 meters became standard equipment on HF transceivers more and more hams have migrated to the lowest of VHF bands for the challenges it presents and the interesting propagation phenomenon.

However, the magic is often more marketing than reality. Or perhaps it's black magic rather than white magic. According to the hype 6 meters, when it opens, allows QRP stations with a whip antennas to make QSOs with ease, and even world-wide DX when the solar flux is high.

This is not what we typically experience. I would prefer that our expectations reflect the reality than the marketing. It's a wonderful band but not easy to achieve good results.

I'll reflect on the major reasons, as I see them, now that we're nearing the end of this summer's E season. You might also read the World Above 50 MHz column in the August QST for additional insight and links, since I noticed there are overlaps with my own thoughts. I did reasonably well this year despite making do with no antenna, compared to the small yagi I had last year. Having 100 watts rather than 10 watts with the KX3 made a difference. I am now up to 19 countries since coming back to 6 meters last year.


Propagation is, of course, not the same everywhere. Sporadic E like many propagation modes is better at lower latitudes. In particular, lower geomagnetic latitudes. Since the geomagnetic pole is located in northern Canada we are at a disadvantage.

Quite often we hear stations to the south working stations we cannot hear at all. But then this is also true for F-layer propagation due to ionospheric absorption even during minor geomagnetic storms. Where you live matters on 6 meters as much as it does on other bands.

Internet: a boon and a road to disappointment

Back in prehistory (the 1980s) spotting clusters were rarely networked. There was no convenient means to discover openings by receiving reports from the global ham community. Ardent 6 meter operators used receivers with scanners (and squelch), monitored the informal 6 meter coordination net on 28.885 MHz (10 opens before 6 meters as the MUF rises), telephone ("Hey, the band is open, get on!") or simply put a lot of time in front on the rig.

Today I can be almost anywhere and receive activity reports on my smart phone. It is also possible to program alerts for 6 meter spots from your general geographic area. There is really no excuse for missing openings.

The downside of the technology is constant interruption and consternation. Unless you are a fanatic the constant stream of information and alerts can become annoying during E season. You can ignore the interruptions but then you may worry that you're missing out. Or, if you are not at home, you will fret about what you are missing.

When you do react by heading to the shack you will often be disappointed. Openings are fleeting or limited to so small an area that you hear nothing. Disappointment can turn to frustration since this happens so often, and can be especially aggravating if you are chasing a needed grid or country.

Do you sit there for a while, listening to white noise, or do you give it up and go back to what you were doing? Don't be surprised when you do leave the shack that another report, maybe even for the same station, appears just minutes later. Rinse and repeat. I almost find myself wishing for the end of the E season.

E clouds are small and rarely well positioned

Sporadic E is not at all like F layer HF propagation. While the science behind the phenomenon is incomplete we do know that the formation, movement, size, shape and dispersal of these high-ionization regions evolves rapidly. Long-haul DX involves multiple E cloud hops (multiplying the variability) or coupling to other propagation modes, including F, TEP, aurora and perhaps even tropospheric ducting. The complexity and uncertainty makes for a lot of excitement, and operating angst.

When you have a good, clean and direct path via the E cloud between two stations signal strength can be fantastically strong. These are the times when the smallest of stations can achieve great results. Alas this is not typical. Most of the time the path may be by scatter off the cloud (not direct path) or weak. When this happens the relative strength can be -30, -40 db or worse than the direct path. QRP and a whip won't cut it.

A lot of time can be spent waiting for the ever-evolving E clouds to momentarily set up perfectly so that the wanted DX station pops up 10 db and becomes workable. Miss that window and you go back to waiting. In the meanwhile you notice all your buddies just one grid square away are all working the station you might not be able to hear at all for most of the opening. For example, in June I worked an S5 (Slovenia) who suddenly popped up with a strong CQ. By the time I finished transmitting the spot to the cluster he fading to nothing. I never heard him again, and probably did anyone that reacted to my spot.

Over my head

Multi-hop sporadic E propagation does not need to involve the ground, just as it does not need to do so for F layer propagation. It is very possible for signal paths to go right over your head to connect points on either side of you. An example is a frequently noticed path from Europe to the central US, with nothing heard in VE3 despite our being directly on the path.

When this happens there is little you can do other than hope that E cloud somewhere to the northeast will increase in intensity and bend, or at least scatter, signals down to the ground. The wait may be long. I've experienced the phenomenon myself numerous times, especially years ago when I had a good antenna for 6 meters. This is one more instance where patience may be rewarded, at the cost of lots of time spent in the shack listening to white noise. It does happen, as I've exper

Beacons from nowhere

6 meters is overflowing with beacons in every imaginable corner of the globe. When conditions are good they can even QRM each other. Beacons are a great way to spot band openings that you can rely on since the beacon is absolute proof that the band is open to a particular area.

Except we may be disappointed. Some beacons are placed in areas where there is no activity at all. Or the local hams are at work. It can be frustrating when a beacon in a needed grid or country comes pounding in and no one is active just then. As the opening wanes and the beacon fades into the noise not to be heard for another year or two you might begin to wonder why you even came to 6 meters.

Weather vs. 6 meters

By weather I don't mean how weather affects 6 meter propagation. What I do mean is that peak E season is during the time of year when the weather is at its best in this part of the world. Our winters are long and cold and spring drags on interminably. When summer truly arrives everyone's thoughts turn to the outdoors. Canadians have a tendency to jump into a frenzy of vacations, sports and outings to cottages, lakes and beaches, fitting in a year's worth of fun into 3 months. I am no different.

It can be difficult to go downstairs to the shack when 6 meters is hopping. Not only is it the summer weather but also that 6 meter's diurnal cycle means that the best times are late morning and early evening when even on the hottest days it is very comfortable outside. Stations in more southerly or tropical locales might find the shack a relief from the heat, or they can wait for cooler weather since sporadic E and TEP are more common throughout the year. But not at this high geomagnetic latitude.

Balance is required. With no regrets I will often go out and enjoy the sunshine even though the band is full of signals. There is always tomorrow. Although I love this hobby I don't want it to become an obsession.

Been there, done that

Early in the sporadic E season every station you hear beckons for attention. You want to work every station you can hear. By July many of us ignore most stations to concentrate on the most interesting and rare openings. By August I get a little testy when the band opens again to the same old places and I hear all the same old stations.

This is the point when it is the time to move on. Some enjoy talking to the same folks if only to keep current the connection to fellow enthusiasts. I prefer novelty. No offense intended, but when I hear another opening to W4 (or even KP2) in this waning part of the sporadic E season I am tempted to just turn off the rig. They may feel the same way about VE3.

How do we deal with all these irritations and frustrations?

My prescription is pretty simple, though perhaps not to everyone's taste. I would summarize it as follows:
  • When the interest wanes turn off the radio or QSY back to HF. Don't obsess over 6 meters. There will be other openings to work, whether tomorrow or next year.
  • Put up a bigger antenna higher up. Small antennas down low do well for the typical single-hop sporadic E openings with their relatively strong signals and high elevation angles. For long haul DX experienced operators generally agree you need something more to increase your probability of success. Just a few db can make a big impact since most DX openings are marginal.
  • Enter a contest. This is one way refresh the enjoyment of working the same old stations again. Consider especially the ARRL June VHF and CQ WW VHF contests occur during the E season peak. You might even become enthusiastic enough to become a rover and activate a nearby rare grid square.
  • Study propagation science to understand the beast you are contending with. K9LA has some good information on VHF propagation on his web site, with links to other material. Even Wikipedia will point you to numerous scientific references.
  • Exploit services around the internet. For example, DXMAPS has near real time plots of sporadic E MUF across the globe. Real time chat can be found at ON4KST.
  • Go digital. There is an increasing amount of JT65 activity on 50.276 MHz where despite marginal openings or poor antennas successful QSOs at negative SNR are common. This is on my list of things to try sometime in the future.
Should you wish to skip all the marginal and rare propagation modes you can always sit out the next few years until the peak of solar cycle 25, sometime around 2023. When F layer propagation come to 6 meters the results can be fantastic. By the time cycle 22 was waning I accumulated 70 DXCC countries and all continents except Asia. That quite good when you consider than most of Europe and in fact much of the world did not have a 6 meter band.

If you decide to wait keep in mind that cycle 24 was a bust for 6 meter F layer propagation at this latitude. Cycle 25 might not be much better. I doubt that I will live to see another solar cycle that compares to what I experienced in 1989, based on long term predictions of solar activity. Instead I try to appreciate sporadic E, no matter how whimsical it may be.

I'm staying on 6

Don't be misled by negative points I've written in this article. Despite everything 6 meters is a lot of fun, a challenge and offers an opportunity to learn more about propagation science. Just be wary since too much of a good thing often turns bad.

6 meters is definitely planned for my next station. Initially I expect to refurbish my venerable Cushcraft A50-6 (purchased new in 1985). That will likely be the subject of a future article in which I strive to improve the antenna's performance. I initially plan to have it 20 to 25 meters high, depending on towers and placement of higher-priority HF antennas. I have a 40 meter long run of Andrews LDF7-50A Heliax ready to go.

Once I have a feel for antennas at various heights versus propagation modes I will settle on a more permanent arrangement. I expect to be on 6 meters for a long time to come. Occasional bouts of frustration can be dealt with by pressing the band switch on the rig.

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