Thursday, May 6, 2021

Sporadic E Season Begins

Seven weeks before the 2021 peak of sporadic E propagation in the northern hemisphere the 6 meter band is hopping. There is lots of activity and DX contacts are in the log. Although nothing exotic what I have worked and heard wets the appetite. I see many others hungering for the DX as well. I know that I'm ready.

The DX I've worked so far is in the Caribbean, Central America and one in Europe. I have heard more, including several of the European big guns, the west coast (California), and north and central South America. Stations not far to the south have had more luck linking sporadic E to TEP to work South America. I'm a little too far north for those openings. Our time will come.

What is clear this early in the season is that the FT8 activity level on 6 meters is greater than I've seen before. There are many signals even when there is no sporadic E in evidence. These are paths of less than 1000 km, typically tropospheric and perhaps some E-layer scatter. There are lots of CQ'ers hoping to get lucky.

With so much excited anticipation of DX propagation there is little excuse to not work DX on 6 meters this year. As many old hands on the magic band have noted, FT8 has uncovered the existence of sporadic E propagation and TEP linkages that had previously gone unnoticed. The ability to monitor all activity without tedious dial spinning or monitoring beacons, data collection by PSK Reporter and the continuous CQ'ing by enthusiasts have highlighted numerous instances of unexpected propagation. This includes single decodes of distant stations, propagation at unusual times of day, polar paths and extremely long path DX. The latter includes VK/ZL and central Asia from here in eastern North America.

Despite my initial reticence to abandon CW and SSB on 6, I am now a believer. The reason is a simple one: FT8 delivers the goods. It isn't just "youngsters" like me who've gone digital. Octogenarians of my acquaintance have learned the digital modes and are having a blast on HF and on 6 meters as well. Old dogs can learn new tricks, and so can you.

Objectives for 2021

At the end of sporadic E season in 2020 I stated that my DX goal this year is to surpass 100 DXCC countries on 6 meters FT8 this year, and I've since made the promised station improvements to make it possible. With 90 countries worked and 81 confirmed it would seem that this is low-hanging fruit. It isn't. 

I am at the stage where additional countries are increasingly difficult to work. They are farther away, rely on rare multi-hop opening, and many operators in those distant locales have small stations or deal with pervasive man-made QRN. The station improvements will help, especially the kilowatt amplifier. Barring disasters I fully expect to reach this milestone in the next few months.

My other objectives are closely related. I want to explore more polar path opportunities to work west, central and east Asia. Some of these can occur at odd hours so I will more often leave the station monitoring overnight for hints of polar propagation (I already monitor activity during the day when I'm busy elsewhere). The north polar region is in full daylight at the sporadic E season peak and the terminator is enticingly just out of reach from my QTH. This is one of those times I wish that I lived further north!

OH, LA and SM stations occasionally appear in our late evening, and central Asians such as UN can appear after sunrise in the very early morning (5:00 to 7:00 AM local time). If I see these signals in my overnight monitoring I will make a point of being in the shack at likely hours during the weeks bracketing the summer solstice.

Other objectives include KL7, ZL, HL, LU, CE, Middle East, Russia, TZ among other Africans, and other known active countries that I've heard but have not been able to work. It's a matter of luck and, yes, power. All are possible. There are also numerous European countries that I've been unlucky with. You would think with so much within reach that another 10 countries would be easy, but it really isn't. My stretch objective is 100 countries confirmed on LOTW, which will likely require working 20 to 25 new countries. Not everyone uses LOTW and I no longer use paper QSL cards.

Using a kilowatt

FT8 is not a low power mode. For digital, as it is for traditional modes, many times low power is sufficient and other times no amount of power is enough. Sporadic E gives few gifts and you do what you must to meet your operating objectives. My objectives are challenging enough without a power handicap.

The ACOM A1500 works very well on 6 meters. Tuning and high power behaviour are not noticably different than when used on HF. For the time being I am being cautious about the power level in case of splatter/distortion and overheating. At approximately 900 to 1000 watts of average SSB power -- our legal limit is 2250 watts PEP -- there are no problems. 

A nearby friend confirms that my signal is clean. Temperature for continuous FT8 operation is fairly high but within the amplifier's comfort zone. After several minutes the temperature plateaus during transmissions. It drops during receive periods. For FT8 and similar modes the duty cycle is a little below 50%. While similar to CW and SSB during transmission, it is closer to 25% during a QSO since half the time is spent listening. So do watch your amplifier closely if you are new to digital modes.

Not surprisingly my QRO CQs get more replies. When I call a big gun with a weak signal there is a good probability that I will be copied. Several DX stations have answered my CQs, and that's a promising indicator. Of course when conditions are good the same happens when I run 10 db less power.

Despite the QRO there are stations that give a signal report lower than the one I give them. This may be due to QRN or other problems at the other end in comparison to my typically very quiet rural QTH. The SNR calculation by WSJT-X provides relative rather than absolute signal reports so puzzling disparities are common.

I don't use the amp at all times. I will turn it on when DX is likely, spotted or heard and I need it to get through. PSK Reporter is used to monitor whether my high power CQs can open the band. Once the amp is on I tend to leave it on since tube life is negatively impacted by power cycling. 

Focussed on DX

When there is a DX opening or an opening is likely I focus almost exclusively on that. Single hop signals (within a radius of 1000 to 1500 km) are ignored other than to see what they're working so that I can predict the progression of the opening. 

This creates a dilemma when close stations call me when I am focussed on DX. At those times I almost never reply. FT8 is slow enough that I will not take 1 or 2 minutes of precious time to work them. This may seem impolite to some. It mostly seems to be stations that do not or cannot hear the DX and are eager for what contacts they can make. Some may want my grid, and there are Americans who consider Canada to be DX.

When the rate is slow I may take the time to reply, but not otherwise. However, one rule I live by is that when I make a directed CQ -- CQ DX, CQ EU, CQ SA, etc. -- and a nearby station calls my on my transmit frequency I almost never work them. It is very impolite for them to do that since if a weak DX station replies on my transmit frequency I might not be able to decode them. Most operators know that a transmit frequency is chosen because it is quiet and will reply there for the best chance of a QSO.

I wish that automatic reply on the called station frequency was not a feature of WSJT-X. It is and we must deal with those who use that feature, appropriately or otherwise. So if I call CQ EU or CQ DX and you are not in Europe or DX, respectively, and you want a QSO with me do not call on my transmit frequency. Transmit elsewhere and I may reply.

A few go so far as to stalk me. To escape their unwanted calls on my transmit frequency I QSY. They follow. I continue to ignore them. You would think after 5, 10 or more attempts to work me they'd give up. I have to wonder whether it's a deliberate tactic to punish me for not working them. My memory is good and I usually remember their calls. I am therefore more likely to ignore them in future when I am not focussed on DX.

Those using JTDX software have another way of dealing with non-DX callers. There is a feature to filter callers that are not in the target region, and there are other helpful feature. The price is that you may miss some stations that you might otherwise want to work. Since I use WSJT-X my approach is to disable the "Call 1st" feature and choose who I reply to, or no one at all. Many big guns on 6 use JTDX and I may eventually do the same.

Perpetual CQ'ers

There are some hams who seem to CQ on FT8 for hours on end. I think that's odd behaviour but they seem to like it. For my style of operating it is a nuisance since they fill the monitoring pane with their transmissions and during busy openings it adds to the QRM. Those within ground or tropo range are inescapable unless, by chance, the DX opening is in a direction that puts them in a pattern null.

The perpetual CQ'ers from last year are already active. I don't understand them and I don't think I want to! As a friend of mine is wont to say: "it takes all types!" They're present on HF and 160 as well.

Dealing with more activity

It is wonderful to see increasing activity on 6 meters. My subjective impression from activity so far is that activity will be higher than last year, and almost all of it will be on FT8. With 3 kHz of spectrum used by the vast majority there will be QRM. Due to the nature of the mode there is a strong incentive for everyone to congregate on one channel.

Alternatives include the intercontinental window at 50.323 MHz and FT4 at 50.318 MHz. I wish more DXers used the intercontinental window since that would benefit those of us focussed on long haul contacts. This has not worked too well since most hams are glued to 50.313, and since this is as true of those far afield as those in NA, the majority of DX can only be worked there.

I did work a few new ones on 50.323 MHz in 2020. This year I hope that more DXers will QSY when the QRM grows intense. My observation is that use of the intercontinental window declined in 2019 and rose in 2020. Many don't experience as much QRM on 50.313 MHz as those of us with quiet locations and good antennas and so may see the need to QSY. However, I am merely speculating.

QRM gets so bad at times that I have failed to complete DX QSOs due to a North American stations jumping on the frequency and obliterating the weaker signal that they probably aren't seeing. This was common for Pacific openings since I must contend with QRM from across North America. Local QRM is less of a problem when pointing northeast to Europe. WSJT-X is very good at decoding more than one signal at the same frequency (audio offset) but there are limits. The software can't perform magic.

I am also hoping for more FT4 activity this year. QSOs are twice as fast as FT8 and thus can put more DX in the log during the usually brief openings. I tried 50.318 MHz a few times last year during DX openings and only heard North American stations. The majority of the time FT4 works as well as FT8 since its SNR performance is nearly as good. 

Monitoring...

I am monitoring 50.313 MHz as I type these words, and all I see is a few nearby stations. DX is uncommon this early in the season but you never know. There are hams who want to tell them when DX openings are expected. It comes from an HF mindset with its more predictable daily and annual cycles. Sporadic E propagation patterns are suggestions and probabilities, and not dependable predictions.

Regular monitoring of 6 meters is required. Alert tools are available that can help but it's really requires making the effort to monitor. The unpredictability is both aggravating and a challenge.

I hope to see you on 6 meters this season. If you're not DX and I don't reply please don't be offended. It's nothing personal. There are many DX-free days when I am happy to spend an hour or more working single hop openings. Although not alone in FN24 I appear to be the best equipped, which may explain the attention while I focussed on DX.

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