Planning for 2025 and Beyond

Last year I stopped doing end of year retrospectives. They're of value to me though perhaps not to others. Since early in my blogging it was an exercise to track my ability to meet optimistic objectives which, being optimistic, were often missed. But if you don't try then you won't do. 

I keep a list of planned and ongoing projects near me. There is a feeling of accomplishment when I can put a check mark next to an item. For many projects that doesn't happen and they either roll into the new year or are discarded. Discarded objectives are those deemed impractical, no longer relevant or superseded by better ones.

The blog itself is an interesting study. You might think that after 11 years I'd run out of topics to write about, yet that never really happens. As long as I'm working on projects -- doing or learning -- there will be something worth writing. The split between and depth of technical and operating subjects varies with my interests. Early in the blog I focussed on small antennas for a modest QRP station, but no more. Not every article can be of interest to everyone and I don't try. I can only hope that the articles that I write are worth reading.

2024 blog productivity is at the bottom of the heap when measured in articles published. This is article number 43, the last for the year. Early in the year I hinted at the reason and there is no need to elaborate. Life throws curve balls at us from time to time. My enthusiasm for the blog hasn't changed all that much, at least not yet. I hope to get back to about one article per week in 2025.

In addition to my own projects I remain active helping others with tower and antenna work. That's in addition to my non-ham activities. I often joke that I've never been so busy since retiring!

Winter projects

In our cold climate, winter is a good time to work on projects indoors. I avoid major tower and antenna work during the cold months unless I'm in a hurry or there's a repair to be done. Most tower work can be done in winter but it's uncomfortable.

Antenna switching software: I am currently doing the design for a complete rewrite of the UI (user interface) half of the software. There are several deficiencies that cause operator confusion, such as showing buttons for most of the antennas, including those for other bands, but not all the available antennas for the current band. Separate windows for left and right radios (or separate PC for multi-op) will also help. There is much more that I'll describe in the new year when the design is complete.

Prop pitch motor controller: I have a partially built Arduino-powered digital controller that I have set aside for several months due to higher priorities and some difficulty understanding op-amp circuits. The first phase of the project is direction indication for both motors (40/10 and 20/15 towers) to be followed later by rotation controls. In a later phase it will be controllable from the PC.

Rotator refurbishment: In the basement there are a disassembled T2X (Tailtwister) and prop pitch motor gearbox that need a lot of work before being ready for use. Most of the work is straight forward but time consuming. 

Harmonic stubs: After experimentation and measurements, I never did get around to making stubs and installing them into the station. The most important are those for 80 and 40 meters (harmonics on 40, 20 and 15 meters). Stub filters are quite simple and complement the low power BPF that I have, and they're far cheaper than high power BPF.

SO2R & 2BSIQ: This is a skills objective. I have begun changes to the station (hardware and software) to try and increase my contest results with SO2R, including 2BSIQ. There is much more to do. Although I don't plan to win major contests (not that I could!) it would be great to do better.

30 meter delta loop: I need WARC band antennas for general DXing. The simplest is this one since I can build and install it during winter. It'll go on one of the big towers just high enough for tractors to roll underneath. That way it can remain in place year round. I've done the models and assembled a few parts for it. It'll be switched via the 160 meter antenna feed system.

Console: The operating desk will be rearranged for improved SO2R contest operating. This includes rigs, amplifiers, rotator controllers and PC monitor(s). I've discarded a couple of plans that, although they look pretty, are not ideal for single-op contesting. The console must also allow rapid reconfiguration for multi-ops and back again; accessibility is more important than aesthetics.

Trees: There are numerous large dead trees that I need to take down. I've started the work. This job is radio related because a few of them threaten antennas, and in one case the guys for the 150' tower. It would be a mistake to think that because I am comfortable working at heights that the work isn't difficult. Trees are nothing like towers and although the safety equipment is similar there are important differences. Winter is the ideal season for tree cutting.

Spring and summer projects

My list of tower and antenna jobs is growing. Some of them can be started during the cold months so that I'll be ready when the weather warms up. That is, if I have the time.

Prop pitch motors: I am having ongoing problems with the motor that is "upside down" driving the mast for the upper yagis of the 20 and 15 meter stacks. This year I would like to convert it to chain drive. A chain drive eases maintenance and is inherently waterproof since the gearbox cavities face downward. I have a tentative plan that leaves the mast and antennas in place. A related project is a chain tensioner that increases the narrow adjustment range of the current system. The prototype is ready for testing.

TH6: Raising the yagi a few feet will reduce interaction with the rotatable 40 meter yagi beneath it. I may wait until spring even though it can be done during winter. A second problem that I'd like to resolve is that the SWR soars during heavy rain. Water must be getting into one or more traps and is unable to drain quickly.

40 meter reversible Moxon: Construction is ongoing and it should be ready for raising and testing in the spring. The XM240 will be likely be fixed south on another tower, or simply removed for a while.

80 meter yagi rebuild: This is more of a fall project to avoid the bugs and other perils of mid-season work in the hay fields. I will replace the tower driven element with a taller one, build better guy anchors, choose a more efficient parasitic element configuration, perhaps add SSB and a better 160 meter system, among other improvements. I am almost afraid to touch the antenna because it's been so good and reliable. But I can make it better and I will, one step at a time.

Amplifiers: Solid state amplifiers are in my future. The tube amps I have -- Acom 1500 and Drake L7 -- are clean and reliable but difficult to use in a contest. Those who stick with tubes will use amps like the Alpha 9500 and Acom 2000 that allow automatic tuning and rapid band and antenna changes to some degree, but not quite as good as modern transistor amps. They're expensive but are becoming necessary. This is especially important for guest operators that find them difficult to manage on top of everything else they must learn about the station.

What the future holds

The pace of station building has been trending downward. That isn't surprising since I have done a lot since moving here 8 years ago. What I have is pretty good and more brings additional maintenance that I'd like as grow older. Who will climb the towers when I cannot? There are few young hams doing tower work and even fewer who will do it for the opportunity to contest from my station.

Expect refinements rather than major projects. I may put up a small tower of about 20 meters height but that will be it for towers. I am running out of room on the existing tower for new antennas. The pace of change will shift toward the shack rather than what's outdoors, especially software and new technology to improve contesting and DXing.

Let's peer into the crystal ball for possible station evolution for 2026 and beyond.

Tower: As mentioned earlier, I may need to erect another tower to avoid crowding (interactions) for the additional antennas I would like. There are several possible locations, and I haven't decided whether it should be guyed or self-supporting. The former is cheaper while the latter can fit in a smaller space. One of my criteria is to avoid restricting movement of farm equipment that guys inevitably entail.

Swing gate: For additional flexibility, I'd like to put a swing gate on the lower yagi of either the 10 or 15 meter stack. Since propagation on 10 meters has a shorter duration centred on the solar maximum I will most likely do it for the 15 meter yagi. This will permit stacking gain on 15 meters in most directions. The antenna is big but not too big for this project. I'd like to get the project started in 2025.

20 meters: The 5-element stack performs very well, but for one deficiency. The lower 5-element yagi doesn't rotate and ought to be higher to be more effective when used alone. A rotatable 3-element yagi at about 30 meters would be ideal, on a new tower or side mounted with a swing gate. The latter will likely require removing the TH6 (currently fixed south). That isn't a bad idea since traps are inefficient and I'd like to eliminate them entirely. However a trap-less tri-band yagi like the Skyhawk is not easily rotated when side mounted. I need to evaluate the possibilities.

160 meters: To do better on top band requires gain. My options are limited since I will not put up a dedicated tower for it. An additive array might be my best option. The second element could be had by shunt feeding the other high tower or with a new and efficient 160 meter mode for the 80 meter array. Both have their complications.

More multi-ops: As much as I enjoy operating on my own -- which I did not when I was younger -- I would like to organize more multi-ops. That will require station improvements from notes I took after two trial runs in 2023. I also can't overlook the need for operators: the local pool of contesters is limited. I have ideas that must be followed up, and that may not be possible in 2025.

Propagation

The high bands are wonderful while the solar flux continues high. That won't last. 2025 may be last year in which record-setting contest operations are possible until the next maximum 11 years hence. I must adjust my priorities if I'm to take advantage. For example, accelerating the purchase of amplifiers and other equipment. 

Another choice to be made is whether to do CQ WW single op to see how far I can go with my skills. That will require a lot of SO2R and 2BSIQ practice. There will be opportunities if I delay more multi-ops until 2026 and beyond. As the solar declines the high bands will be less open and fewer operators will be needed.

I can't do it all and the sun follows its own schedule. It's a dilemma.

Happy new year

This is the time of year when we gather with friends and family. The amateur radio community is no different. I had a pleasant Christmas lunch with several local and not-so-local hams. Contesters should recognize the call signs of all those present.

Left to right: Vlad VE3JM, Chris VO2AC, Dave VE3KG, Frank VO1HP, and me. My thanks to Vlad for the picture (taken by our server using his phone).

Have fun, stay safe, and I look forward to working you in the contests in 2025.

Finishing the 160 Meter Gamma Match

When the time care to redeploy the 160 meter antenna for the winter season, there were a few improvements. These are mechanical changes that make the system better able to survive the elements. Since there were no electrical changes there is no difference in performance. However, I did include a provision for future expansion.

The new features of the shunt-fed 160 meter tower:

• Weatherproof enclosure
• Additional support for the 60' long gamma rod (2-wire cage)
• Improved RF high voltage insulation and isolation
• Easier adjustment of the feed point impedance
• Expansion room for additional antennas
  

Gone are the margarine tub at the feed point and the unstable bottom termination of the wire cage gamma rod. These are holdovers from my aborted attempt last year to improve performance.  The new system is built to last.

The one thing that's still there is the flimsy radial attachment band made from aluminum flashing. It'll be replaced in time. It works well enough and it is easy to attach radials. What it lacks is strength. When deer (or errant hams) trip on a radial, the aluminum band easily bends. While it hasn't been seriously damaged yet, it may be a matter of time.

The new capacitor enclosure is staked on its supports. The strut to the cage gamma rod telescopes and is insulated from the tower and nearby cables by the pivoting ABS pipe surrounding it. Recall that the potential across the gamma capacitor at 1000 watts is close to 2700 volts. The isolation is critical for safety and performance.

This is a side view of the strut. There are hose clamps on either side of the ABS pipe to hold it in position after adjustment. The rear clamp also holds the wire from the capacitor. There are two hose clamps for the telescoping section. A length of aluminum angle provides a far better bottom termination than the temporary system it replaces. The gamma cage wires are held 40 cm apart from top to bottom.

The gamma rod wire was also replaced. Previously I used soldered together scraps of #12 stranded THHN since I didn't want to waste good wire on what was at the time an experiment with a cage gamma rod. The new wires are unbroken lengths of #14 solid black THHN taken from a decommissioned wire antenna.

The ABS enclosure is pretty tough and has room for a large transmitting variable capacitor. It's black for UV resistance. The sealed cover has to be removed to adjust the capacitor. I didn't want to pierce the enclosure for an adjustment that typically only needs to be done once per season.

The aluminum angles that comprise the mounting brackets were hammered into the ground with the enclosure attached. That worked out better than trying to make the holes line up after pounding them in first. I broke up the sod where they penetrate the ground so that they could be pressed down with minimal force.

Aluminum strips hold the fixed transmitting capacitors, and there is room for one more if needed. The variable sections are in series to prevent arcing; combined this way it's good for up to 4000 volts. The usable range of the gamma capacitor is 150 to 175 pf. A small capacitance (high reactance) is needed to cancel the large inductive reactance presented by the gamma match.

If you look closely at the left side of the enclosure you'll see two openings for coax connectors that are currently taped over. Those are for future antennas that will share the transmission line via relays. I have lots of Heliax but burying it is a bother. I'll use these for non-contest bands such as 30 meters so that sharing doesn't cause a conflict during contests. 

A new trench and Heliax runs will only be prepared when I have more contest band antennas on this tower -- it currently only has the 20 and 15 meter stacks. The 160 meter vertical can be used at the same time as the stacks.

I hoped that a cleaner installation would help broaden the SWR bandwidth but it didn't work out. I expected better based on ON4UN's Low-Band DXing. It's a problem because, not only is the voltage very high, the SWR bandwidth remains narrow. It is no better than 70 kHz for an SWR below 2. 

Amplifier tuning must be done for frequency changes of more than 10 or 15 kHz. That's annoying during a contest. For the ARRL 160 meter contest I placed the frequency of minimum SWR a little higher than shown. I lowered it now that I'm back to mainly DXing on top band, CW and FT8 at 1840 kHz.

I don't know why the cage gamma rod doesn't increase the SWR bandwidth. From all the research I've done it ought to do so. With an electrical height of ⅜λ the impedance is very sensitive to the position of the tower tap point. Even so it ought to be better. Going from a single wire to a cage made no difference. I'm stumped. More modelling investigation is in my future.

The one thing I did achieve was to reduce the gamma rod spacing. It used to be between 2 and 2.5 meters (8') from the tower. That's a lot. With the new system the separation is now about 1.6 meters (5'). Getting to that magic 50 Ω value was easier. That's a relief. I used to dismantle it over the summer since it interferes with antenna work. I may be able to leave it in place year round. Only the radials will need to be rolled up for the hay season.

In windy weather the SWR oscillated due to the motion of the 60' long gamma rod wires. Tension on the wires helps but is insufficient. During one wind storm the wires twisted together. I made two improvements to eliminate the problem. 

At the 30' level I installed a support for the wires. Both the long strut and the cross piece are PVC pipe. The wires fit into slots and are held there with wire ties. A few inches of aluminum angle are bolted to the cross piece and held to the strut with a u-bolt. The tower clamps allow for full 2-dimension adjustment. (Apologies for the lack of a close up but I'm not climbing to take a photo!)

The strut to the gamma rod pivots at the tower to allow ease of tension adjustment. I first tried this with the rock on a wood plank that leaned on the end of the strut. That created some havoc with the impedance. As already discussed, the bottom of the gamma rod has a very high impedance so it is very sensitive to foreign materials that are poor insulators or that can absorb water. 

The thin mason line doesn't affect the impedance. A small rock tensions the wire and anchors it to the ground. In 70 kph winds we had following the work, the impedance variation was negligible and nothing shifted position.

That's it for this year. I need to do more investigation to discover the reasons for the high inductive reactance that is the cause of the poor SWR bandwidth. I already determined that the tower tap point is critical, but it is difficult to tame the reactance while also putting the resistance within reach of 50 Ω. It's annoying even though amp tuning can deal with it. 

Despite my complaints, the antenna still works great. That's worth a lot.

Yagi Interaction: One Rotates, One Doesn't

Modelling antenna interactions is difficult. It is worth the effort since it is far more difficult to resolve problems after the antennas are on the tower. When I suspect a deleterious interaction, I take the time to do the modelling rather than cry afterward. When my suspicion proves to be wrong I don't regret having done the modelling work. I always learn from it.

On the right is a photo copied from an earlier article so that you don't have to flip back and forth to understand the problem I am currently addressing. The antennas on the tower from bottom to top are:

• XM240 at 21.5 m (72'), rotatable
  
• TH6 at 24 m (80'), south
• 80 meter inverted vee, apex 31 m (102')
  
• 10 meter 5-el at 33 m (108'), northeast
• 40 meter 3-el at 43.3 m (142'), rotatable
• 10 meter 5-el at 46.3 m (152'), rotatable

There are also 4 sets of guys that, though broken up into non-resonant segments on all HF bands, interact with the yagis. 

It is a nightmare to fully characterize. Luckily the situation can be simplified with a few mostly reliable rules-of-thumb (heuristics):

• Down pointing guys and wire antennas below a yagi, especially if non-resonant or resonant on other bands, have minimal interactions with yagis above them.
• When stacking yagis vertically, they have little interaction with those for higher bands, except at very small separation. The reverse isn't true unless the separation is at least one (the longest) boom length.
• Interactions from guys, wires, towers and other antennas increase the closer they come to the tips of the antenna elements.

Heuristics provide guidance, not guarantees. Modelling are measurements are better options in critical cases. Relying on SWR deviations alone as your guide is not recommended since that typically only occurs when the interaction is so severe that the yagi antenna pattern is seriously degraded; that is, of gain, F/B and SWR, the latter is usually the last to show a measurable change as the magnitude of the interaction increases. Since measuring gain and F/B is exceedingly difficult and rarely done with usable accuracy in an amateur station, models can provide valuable insights.

After I rearranged yagis a year ago, I discovered that I had a problem. When the XM240 was turned west the SWR rose to about 2 where it had before been very close to 1. In that direction the TH6 and XM240 are at right angles -- the TH6 is fixed south. 

Yagi side resonance is a type of interaction that I previously described and that I failed to take into account when I installed the yagis in their present positions. The TH6 is resonant on or near the 40 meter band when seen as a short yagi with large capacitance hats.

Rather than attempt to model the TH6 -- trapped yagis can be difficult to model -- I developed a simple EZNEC model for a 3-element 20 meter yagi of similar dimensions. The antenna does indeed resonate near the 40 meter band. Its feed point resistance is low, which is typical of a short, loaded dipole.

The resonant frequency is about 100 kHz higher (7.6 MHz) with NEC5. The boom must be included in the model and the source placed on the boom. The traps and tubing schedule of the TH6 will have a different resonant frequency due to the traps operating as coils on 20 meters that inductively load the "capacitance hats" (reflector and director). There is very little current on the other elements, including the driven element, so it is acceptable to simplify the interaction model by excluding them.

There is a secondary resonance on 10 meters that may cause an interaction with the 10 meter yagi higher on the tower. However, they are much farther apart and in any case the TH6 is (obviously) resonant on 10 meter in its ordinary application. The boom of the yagis are always at 45° (135° by the yagis' forward directions) to each other since both are fixed. In this article I won't be investigating that potential interaction.

Like the TH6, the XM240 is difficult to model with NEC2. It is easier with NEC5 to make an accurate model but I won't bother. There is no need since I will replace the XM240 with a rotatable and reversible 40 meter Moxon, and I have a NEC5 model for it. Most of it built, but I may have to leave it until the warmer spring weather. That's only a few months away although it would be nice to have it for the late winter contests.

It is easy to combine both antennas in the same EZNEC model and then arrange their separation and orientation to investigate interactions. My hope is to find a simple way to reduce the 40 meter interaction that I know is present due to the measured SWR sensitivity when the TH6 and XM240 are at right angles. The same will occur with the Moxon.

My intent is to estimate the magnitude of the interaction without striving for high accuracy. The modelled 20 meter yagi is just a proxy for the TH6 side resonance. There is no utility in a precise calculation that lacks real-world accuracy.

In my modelling exercise I did the following, which I'll discuss in this article:

• Excite the 40 meter Moxon with the 20 meter yagi 2.5 meters above it, pointed in the same direction and with the 20 meter yagi turned 90°
• Excite the 20 meter yagi, with the same conditions as in the previous point
• Repeat all of the above with the 20 meter yagi 5 meters above the 40 meter Moxon

While many other scenarios are possible, these are the ones of interest to me. I have limited space to raise the TH6 higher due to interaction (electrical and mechanical) with the next higher set of guys and interaction with the 10 meter yagi further up the tower. I am focussed on the 40 meter yagi's performance; the TH6 is mostly limited to multiplier hunting in the Caribbean, southeast US, and South America, so problems that are not too severe are tolerable.

The yagis are very close to each with respect to their size, yet that's the actual case on my tower as the opening picture shows. 2.5 meters (~8') is the measured distance. In these EZNEC plots of antenna currents only the 40 meter Moxon is being excited. NEC5 was used for these plots and will be used throughout the analysis since NEC2 cannot accurately model the Moxon.

Notice the difference when the antennas are at right angles. With both pointing in the same direction (or in opposite directions with 180° rotation), there is almost no induced current on the 20 meter yagi. But "almost" isn't none, and that will be addressed. 

Due to the side resonance of the 20 meter yagi near 40 meters (~7.6 MHz, as discussed above) the induced current is quite large. The interaction impacts performance of the 40 meter Moxon. 

What may be less expected is that the 20 meter yagi is also affected. The above plots are with the 20 meter yagi excited. The interaction is negligible when pointed in the same direction, but more pronounced when they're at right angles. Current induced on the forward Moxon element in the first case and on both in the latter. The asymmetry is due to the fields largely cancelling towards the rear per the yagi's design (F/B). I expected more current to be induced on the rear element because the antennas are so close and the Moxon elements are inside the 20 meter yagi parasites. This highlights the value of models over expectations (or guesses).

When isolated from each other so that their performances are unaffected, the SWR curves are much better than these. For the 20 meter yagi, the SWR is 1 (with a matching network) at 14.175 MHz and is less than 1.5 at the band edges. For the Moxon, the SWR is ~1 between 7.05 and 7.075 MHz, and is less than 1.5 across the 40 meter band.

The worst case SWR conditions are as depicted in the EZNEC plots above. I was surprised by the high SWR on the 20 meter yagi because I don't see this with the TH6 and XM240. The 20 meter interaction when the XM240 is turned 90° (to the west) doesn't significantly change the 20 meter SWR. 

The XM240 is coil loaded and the Moxon has large capacitance hats. Those hats are long and are likely responsible for the interaction with the antennas at right angles -- I don't have an accurate XM240 model and I am not motivated to build one just to test this. This model strongly suggests that I will have a problem with the TH6 when the Moxon replaces the XM240.

When the yagis are pointed in the same direction there is less impact on the SWR. For the 20 meter yagi the minimum SWR slides down to 14.1 MHz and rises to 1.7 at 14.35 MHz. For the 40 meter Moxon, the minimum SWR occurs at 7.05 MHz and rises to 1.5 at 7.3 MHz. These relatively small deviations are acceptable, and that is my experience with the TH6 and XM240.

So much for the SWR, what about yagi gain and F/B? Sticking with my original premise that too much detail is uninformative, I have summarized the performance in tables with a minimum of data points calculated from the models. The yagis in isolation (no interaction) are the base line. These figures are calculated over EZNEC medium ground, not free space, so there is ground reflection gain. The Moxon is up 21.5 meters and the 20 meter yagi is up 24 meters.

2.5 meters separation: 14.0   14.1   14.2   14.3  Mhz 

   Baseline    Gain:   13.3   13.4   13.4   13.5  dbi
   24 m         F/B:   18.4   21.6   22.8   20.7  db

   Forward     Gain:   13.0   13.0   13.1   13.2  dbi
                F/B:   15.8   18.3   20.3   29.1  db

   Side        Gain:   13.1   13.1   13.2   13.3  dbi
                F/B:   16.9   19.1   23.0   25.6  db

                        7.0    7.1    7.2         Mhz 

   Baseline    Gain:   11.3   10.7   10.3         dbi
   21.5 m       F/B:   20.9   15.5   10.4         db

   Forward     Gain:   11.2   10.6   10.2         dbi
                F/B:   21.9   14.5    9.6         db

   Side        Gain:   10.9   10.1    9.3         dbi
                F/B:   22.5   10.8    6.3         db

Other than the SWR, gain and F/B of the 20 meter yagi are affected very little. This is one of those interaction cases where SWR changes before gain and F/B are greatly affected. On 40 meters the effect is greater. That said, it is relatively modest, with up to 1 db gain and 4 db F/B lost when the 20 meter yagi is turned 90°.

In the next modelling exercise we increase the separation to 5 meters by lifting the 20 meter yagi higher. That's about the maximum I can achieve on the tower, and I will likely not separate them by more than 4 meters to avoid the interaction risks described earlier.

5 meters separation:   14.0   14.1   14.2   14.3  Mhz 

   Forward     Gain:   13.3   13.3   13.4   13.5  dbi
                F/B:   19.0   24.0   27.9   22.9  db

   Side        Gain:   13.3   13.3   13.4   13.5  dbi
                F/B:   18.4   23.7   28.4   22.8  db

                        7.0    7.1    7.2         Mhz 

   Forward     Gain:   11.2   10.7   10.2         dbi
                F/B:   21.4   15.1   10.0         db

   Side        Gain:   11.1   10.4    9.6         dbi
                F/B:   23.8   13.6    9.2         db

The difference is not large but it is an improvement. Perhaps more important is that the SWR is much better. On 20 meters the minimum SWR shifts back to 14.175 MHz when in the forward (same) direction and 14.150 MHz when turned to the side. The SWR is never higher than 1.5 from 14.0 to 14.35 MHz, which is the same when the yagi is by itself (no interactions). 

On 40 meters, the minimum SWR shifts to 7.075 MHz when in the forward (same) direction and  7.05 MHz when turned to the side. As for the 20 meter yagi, the SWR stays below 1.5 from 7.0 to 7.3 MHz. Again, that's a significant improvement.

Although I did not test for interactions with a similar proxy model for 10 and 15 meters on the TH6, I did an SWR sweep on the Moxon up to 30 MHz. Its third harmonic is, as expected, well above the 15 meter band at 26.35 MHz. I expect the interactions to be minimal especially for separations on the order of 5 meters. I am sufficiently confident that I will avoid the time and effort for the additional modelling. In practice I've not noticed the SWR or performance change on 10 and 15 meters as the XM240 is turned, understanding that without making careful measurements I could be wrong.

Just for fun I excited the Moxon on 20 meters to see what would happen. It actually works! The antennas are apparently close enough to behave as couple resonators, a popular technique for feeding a trap-free multi-band dipole or yagi or to increase the bandwidth of a mono-band yagi. The gain and F/B are very close to that of the 20 meter yagi on its own. 

Unfortunately there is one difficulty: the SWR is extremely high. On 20 meters the 40 meter Moxon driven element is a 1λ dipole. The impedance at the feed point is therefore high because the current is low and the voltage high, just like an EFHW (end-fed half wave antenna). A transformer would be needed to bring the impedance down to 50 Ω. It's interesting, but without any useful application.

After all of this analysis, what will I do? The first step is to raise the TH6 a few feet. That should ameliorate the SWR increase when the XM240 is 90° to the TH6. Based on this modelling exercise, the increased separation will help even more when the XM240 is replaced by the Moxon. Lifting the TH6 and its side mount bracket isn't too difficult so I may go ahead and do it this winter

While the antenna configuration described in this article will not be the same as in other stations, it is likely that many readers have side mounted yagis or wire antennas that are close enough to the top of the tower to interact with the rotating yagi(s). Watching the SWR while rotating the top yagi(s) will determine whether you have a problem. My philosophy is that it is better to know than not know, whether or not one chooses to deal with it.

The Moxon is half built in the snow covered hay field. I'll continue to work on it as time and the weather allow. My hope is to put it into service within a few months. Then we'll see whether the interactions are as found in this modelling exercise.

Great Expectations: CQ WW CW at the Solar Maximum

Before every contest there is a question you must ask yourself: which category?

There is no right answer, just the one that works for you. Elite competitors aiming for WRTC qualification will almost always choose single op all band (SOAB), assisted or unassisted if the rules treat them separately. The rest of us pick a category that interests us, whether as an opportunity to chase DX, win a more focussed category (e.g. 15 meter single op, or SOAB for a country or continent), to shakedown station issues, or as practice to improve operating skills. 

Although not particularly competitive, I wanted to push myself and the station in CQ WW CW. My intent to host a multi-op again didn't work out because there were too many lingering station issues and I really didn't have the time or energy to prepare. That led me to select SOAB HP (single op, all band, unassisted, high power). Hunting for stations and multipliers while running on another band was a test for me rather than the station; the latter could more conveniently done with assistance. 

Since we are at the solar maximum and the propagation forecast for the weekend was favourable, I decided to operate as many hours as I could and run up a high score. I knew that I could achieve high run rates. That posed a dilemma with my modest SO2R and 2BSIQ skills. I intended (and did) do both of those, but not enough to be truly competitive. Winning was not in the cards. My objective was instead to try something that I have never accomplished on my own: 5000 contacts.

SO2R is very helpful to that objective but not mandatory if the runs are high enough. That afforded me a degree of flexibility when the stress of running precluded hunting or running on the second radio. It is still daunting; had I operated 40 hours my average rate would have been 125/hour, or just over 2 QSOs per minute.

The result

This blog is not a mystery novel! I'll show you the result up front and then discuss. My official on time was 44 hours (per the rules); my actual operating time was no more than 42 hours. That's useful for keeping statistics but it does not factor into the result -- you operate as much of the 48 hours as you can. It is a meaningful number in this case so I self-reported it to 3830.

 Band  QSOs  Zones  Countries
------------------------------
  160:  238    13       38
   80:  556    14       57
   40: 1118    23       79
   20: 1195    31       82
   15: 1016    28       82
   10:  963    27       77
------------------------------
Total: 5086   136      415  Total Score = 7,507,375

I passed the 5000 QSO mark at 2323Z on Sunday. It was a near thing! We'll have to wait to see whether the result stands after log checking. I know there are errors, but I hope there are no more than 86!

A meaningful comparison of my result is with my friend Vlad VE3JM since we live in the same area and our stations are similar. The difference is his skill level. He made over 6400 contacts and many more multipliers for a raw score of about 10.4 million. His objective was 10M points so he also succeeded.

To give you an idea of how competitive the SOAB HP category was, my rank in the raw scores is #22. Despite meeting my objective and scoring well, my result will be of no interest to anyone but me. I'm okay with that. I had fun and accomplished something I've never done before.

Preparation

There was a rush of antenna work to be done over the preceding weeks. The previous blog post describes the repair of the Beverage system. I did not mention that the southwest direction was not functioning. That is the reverse mode of the northeast-southwest reversible Beverage. With 5 other directions to choose from I didn't worry about it. A failed splice along the 175 meter long open wire Beverage antenna was repaired several days after the contest.

Copper corrosion on a wire to the radial system hub of the driven element had taken the 80 meter 3-element vertical yagi offline. It took me a while to discover the fault since I thought the problem was due to a Heliax connector. I cleaned the wire, tightened it down and it was back in service. With that done, all of the antennas were operational for the contest.

Finally, a bug was lurking in my antenna switching software which I had to track down and fix. I hadn't noticed it since my last software update since it was triggered by an unusual (and untested) SO2R conflict for a subset of antennas and switch ports.

Preparation of the operating desk was easier. I stacked the Drake L7 on top of the FT950 as the second (right) radio, plugged the second keyboard into the PC and plugged in the SO2R Mini. That took 10 minutes, and a few minutes more to configure N1MM Logger+ for SO2R. This is routine for contest setup. The operating desk looked similar to what you can see in this article, but with two keyboards and an Icom 7610 in place of the FTdx5000.

Since this picture was taken after the contest and there is one notable difference: the FT950 has been replaced by an acquired Icom 7600 that arrived a few days after the contest. That will be my SO2R setup going forward. I'll might say more about the rig change in a future article.

Propagation

Solar flux was high but not very high. A minor geomagnetic disturbance was also forecast. As it turned out, propagation was very good on all bands from 160 to 10 meters for almost everybody in the contest (high Arctic stations excepted). 

Propagation for the CW weekend of CQ WW is usually not as good for us as during the SSB weekend since the solar flux was lower. Also, it is a month later. Less daylight means shorter high band openings the higher your latitude in the northern hemisphere. Since it is summer in the southern hemisphere, there are also fewer hours of joint darkness to work across the equator on the low bands.

Unlike for the SSB contest, 10 and 15 meters needed full daylight to be sufficiently open to work DX. Although 20 meters opened before sunrise, signal levels were low. Sunrise was instead an opportunity to hunt multipliers on the low bands. I was able to work many new ones on 160, 80 and 40 meters at that time of the morning. Since the ionosphere was undisturbed, it was possible to work stations on 80 and 40 well into the morning, whether that was here or in Europe or west Asia. As the sun rose above the horizon, 10 and 15 opened and there was a mass exodus from the low bands.

Here are two examples of the good conditions. During a run Saturday night on 160, I had callers from W6/7, Europe and the Caribbean. On Sunday afternoon, a lengthy run on 20 meters attracted callers from every WAC continent (not Antarctica!). The repaired 20 meter stack was pointed to Europe and north to spray in multiple directions.

Notice in my score that I was able to work about the same number of stations and multipliers on 40, 20, 15 and 10 meters. The number of contacts on 40 and 20 lagged until Sunday when more stations moved down from 15 and 10 as rates there declined.

In short, there was little to complain about -- the ionosphere cooperated. Short path, long path, and trans-Arctic DX paths were all available, with multi-hour openings on the productive path to Europe.

44 hours

That many hours, at my age? It was easier than I expected. My official on time was 44 hours, and no more than 42 hours in the chair. Several breaks of up to 30 minutes were needed to periodically refresh myself. Had I only operated a more civilized 30 hours, my average hourly rate would have had to be 170, or 3 QSOs per minute. That's far more difficult than 120 per hour.

Since I'm a nighthawk, I made the wise decision to operate throughout the first night and then catch a few hours the second night. I was certainly not alert for the entire time, just alert enough to run the pile ups. Fatigue occasionally prevented effective SO2R so I would stick with one radio when that happened. 

Operating close to a full 48 hours has bodily effects beyond sleepiness. That proved more difficult but still endurable. I was early to bed the following two days and I made sure to spend a lot of time on my feet to "reset" my body.

Running

It is still true that I hate running. I enjoy building up the score and being called by many multipliers, but it can be difficult and frustrating. With my "big gun" signal I could usually start a run on a clear frequency by sending "TEST VE3VN" just 3 times. Often the pile up would become quite large within one to two minutes. 

It is a challenge to get stations other than the ones I'm calling to stand by. They end up wasting my time and theirs with discourteous tactics, and that lowers everybody's score.  Yes, it's a competition but courtesy and ethics should never be set aside. Fatigue makes the problem worse, since it gets harder to pull out full calls. Sending partial calls doesn't quench the enthusiasm of many.

A common source of errors is callers who won't correct their call signs. When I suspect an error, to save time I may send their call as I have it along with my exchange. But they respond with their exchange and do not correct their call. Then I have to ask again, and many times they've already moved on. Others don't seem to understand "call?" and just repeat the exchange. Sending a partial followed by "?" can be more successful but it takes time, and time is of the essence when running a pile up.

SO2R and 2BSIQ, though beneficial to everyone, are particularly difficult during hectic runs. Although 2BSIQ is often easier because the operator is in control of both frequencies, I would lose sync between the runs when callers were unruly. Unlike the best contesters, I could not operate both radios as much as I'd have liked. When 2BSIQ worked well (not too many callers and all were courteous) my rate soared to 6 QSOs per minutes. Alas, it never lasted for long.

Yet run I must. You won't make 5000 contacts by calling others. My patience was severely tested but I persevered because it was what I knew I must do to reach my objective.

Hunting (S & P)

S & P on the second radio is difficult when you are unassisted. While running on one radio -- you should always be running on at least one radio when operating SO2R -- the pile up makes it difficult to spin the VFO and copy call signs. Then you must delay the run radio to make your call. It can be very fatiguing in a 48 hour contest. 

It is easier when you a little pistol. During contests like NAQP, with 100 watts everyone is more equal and the number of callers is never large. I can copy the callers on the run radio while hunting and copying call signs on the other. As the intensity of the pile up increased during CQ WW, I frequently had to abandon the second radio to focus on pulling out a call signs from the horde replying to my CQ.

Assisted operators have it much easier. You click on the spot and you call after confirming the call sign -- human and skimmer spots are often wrong. On CW you rarely need to touch the VFO knob. Due to the lack of skimmers on phone it is often necessary to spin the knob. Human spots don't include the majority of stations available to work.

I focussed on running when hunting became too difficult. Look at the summary screen on N1MM where it tells you the equivalent value of QSOs and multipliers (other logging apps show a similar statistic). Towards the end of the contest, mine was about 9; that is, 1 multiplier is worth 9 QSOs. Since hunting mults was difficult and slowing the run rate it was acceptable to abandon the hunt so that I could run faster. 

That's how I coped with the difficulty of S & P while running. With more skill I should be able to do both. The best operators can do it far better than I can.

Lessons learned

The station itself only requires incremental improvement. It's big enough for me. I am working on several antenna projects and control systems that will give the operator(s) better options and fewer distractions. One major impediment was the FT950 -- a radio well beyond its time -- which I have now replaced with the Icom 7600. I'll keep the 950 for backup.

My intent is to give both radios the same "look and feel" so that fewer mistakes are made when the operator is fatigued or inattentive. Although the 7600 is a newer and better rig than the 950, it is hardly modern. I hope that it will work out; otherwise I will not hesitate to replace it. The FTdx10 is available at a similar price but I have concerns about it. That's a shame because its receiver is superb.

The FTdx5000 remains inoperative and I am not convinced it is worth the cost of repair. It is in many respects a fine radio that is also showing its age. In particular I am concerned with its key clicks; the impact on others can no longer be ignored when I run a kilowatt with my large antennas.

My SO2R skills and setup must be improved. I have to do better even if I never again go all out as a single op in CQ WW. I need the skills for shorter and smaller contests like NAQP. That will require practice. No one can help me with that, but I can learn from others. It is important to learn from the best, either from what they say publicly or by speaking to them. I have no illusions or intent to become an expert, just as far as my interest and ability allow.

If I want to improve my single op results, there are the changes that I must consider. These include:

• Rig placement: Some put the radios side-by-side while others shove them off to the sides. I fall into the latter group. I prefer to touch the rigs as little as possible, using standard and custom buttons in N1MM to control them. The main exception is the VFO knob. SO2R ops that like to keep them in front of them like the situational awareness that arrangement provides.
• Amplifiers: Ideal amps for SO2R and multi-ops is broadband no-tune. Both of mine are manual tune tube amps. The need to tune the amps makes me reluctant to do frequent band changes and, in some cases, antenna changes. It doesn't take long to tune them but it feels like an eternity in the midst of the contest.
  
• Keyboards: I quickly migrated to two keyboard SO2R for what I believe are good reasons. I haven't changed my mind. I notice that many of the best operators do the same. What I need to consider is keyboard type and placement. Small keyboards (no numeric pad, etc.) with large keys, including function keys, take up less space and require less physical movement to pivot from one to the other.
  
• Stereo vs mono: For 2BSIQ it is better for the audio from the radio with receive focus to play in both ears. Copy is much better that way, and that means fewer mistakes and repeat requests. I've avoided it since it tends to confuse me; that is, you have to keep track of which radio you're listening to. If you haven't tried this with SO2R, trust me, it's a challenge. The visual cues from N1MM are poor, in my opinion. Manual stereo/mono switching when S & P on one radio is usually better, but I have been doing it for 2BSIQ may have been a mistake.
• Paddle position and use: Some contesters have dispensed with manual sending entirely, whether SO2R or not. I still like to have paddles available for the times I might greet a friend (dit dit) or send a rare message such as "QRL" when someone tries to steal the frequency. For this contest (see the picture above) I moved the paddles off the desk to get them out the way of the radios, mouse and rotator controllers. I copied the idea from others. It reduces clumsiness induced errors but sending can be awkward.
  
• Logging software: Differences abound among contest logging applications. Some are arguably superior for intense SO2R. This has led to a quandary: stick with the evil I know (N1MM Logger+) or switch to DXLog? Although I don't like the overall UX (user experience) of DXLog, I know that it better for SO2R in comparison to N1MM. I must give DXLog another chance, if only to help improve my SO2R and 2BSIQ results. Once I have experience with both I may write about it.
  

Do it again?

After getting this far in the article you might wonder whether I actually had fun. Yes, I did. Part of the fun is challenging myself to do as well as I and the station allow. Of course there is frustration when I fall short, but that prods me to improve myself and the station, which is also fun.

Is a blow-by-blow of my contest experience of interest to anyone? Probably not. There is little drama in discovering that I could easily run on every band and work pretty well every station that I called. My challenges were ones less familiar to casual contesters: how to increase rate and how to find more multipliers?

Since I'm planning to improve, that implies that, yes, I'd like to do it again. Perhaps. It is equally likely that in the 2025 CQ WW CW contest I will host a multi-op. I can use any improvements between now and then for other contests. 

I admit to the temptation of another single op entry next year to see how far I've come in what might be the last CQ WW contest of this solar maximum. The next maximum is more than a decade in the future and who know where I'll be then.

To close this article I'll paraphrase the words of the renowned philosopher of life, C. Lauper:

"Hams just want to have fu-un,
Oh oh, hams just want to have fun!"