Modern Spotting

DX spotting clusters have existed for decades. Originally they were isolated systems accessible via packet radio on VHF or UHF, and therefore limited to the local community. Unless you already had the equipment it required time and money to get connected. The value was dependent on the size of the local DX community and their willingness to connect and spot what they heard.

We built an AX.25 VHF cluster in Ottawa almost 40 years ago. It didn't go well. There were too few of us, the node was difficult to reach (too far out of town) and spots were infrequent, mostly just evenings and weekends. After about a year the node was decommissioned and we donated the equipment to other local VHF projects that had nothing to do with DXing.

Today it's easy. PCs, smart phones and internet connectivity are universal. Pick an app or an internet DX node and you're ready. You can spot at the click of a mouse or do it automatically. You can receive spots from hams across the globe or just your region. There's so much traffic that it must be filtered to avoid being overwhelmed. Then there are the perpetual incompetent spotters and also the limited utility in knowing what DX stations across the ocean might be hearing and working.

Do you want to work the latest rare DXpedition? Chances are that they have a live stream where they post each station worked, including mode and frequency. That's the ultimate in self spotting behaviour. You don't even need to check for spots of these stations. Filling band slots and reaching DXCC Challenge endorsement levels has never been easier. Some think it demeans the value of DX awards, but most hams love it.

Nobody listens anymore. It's time to revisit the topic of DX spotting.

CW

When I tuned to 20 meter CW one afternoon this week there were no spots on the band map. Yet there were many signals visible on the transceiver's waterfall display. I enabled skimmer spots and within 10 minutes there were dozens of spots, only two of which weren't from a skimmer. I am careful to filter for skimmers located in northeast NA to reduce spots of stations I'm unlikely to hear.

CW skimmers work so well that most operators no longer bother with spotting. Whether that's good or bad is a matter of opinion. Skimmers make mistakes, including decoding errors and phantom signals. They may also have antennas too poor or too good to mimic a typical station. 

An increasing number of nodes are installing filters to weed out the problematic spots, whether human or skimmer generated. They're becoming quite good at it, often better than proficient CW ops -- typos are common. Skimmer spots don't include splits (for rare DX), and human split comments are frequently unreliable.

Even on 160 meters where I have excellent Beverage receive antennas there is little need to tune the band. There are skimmers with dedicated receive antennas that perform admirably. It is also useful for any weak station (e.g. QRP) since skimmers pay more attention to the weak ones than humans do. Once your weak signal is picked up by the skimmer you will attract callers, be it for POTA, in a contest, or other operating activity.

The technology has progressed to the point that, like many others, I rarely spot stations on CW, and I can do it without feeling guilty. One exception is rare DX that may rarely identify or not follow standard CQ pattern that might not be picked up by skimmers.

SSB

There are no phone skimmers, at least not yet. They'll come eventually but until then we are reliant on human spots. For those that rely on spots to find stations, rare DX or not, be aware that most stations do not spot the phone stations they hear or work. If you dislike spots and prefer to find stations yourself, this may be seen as unimportant or perhaps a positive. That is not a common view.

There is a way to increase phone spots. It remains largely a feature of contest logging applications such as N1MM Logger+. It is a simple configuration change with which every station you work by S & P (they run and you find them) is spotted, if you are connected to a DX cluster. 

While not mandatory it is recommended by many contesters. The objective is to increase the number of phone stations that are spotted to a level comparable to that achieved by CW skimmers. 

This is the best we can do until we have software that can reliably recover call signs and other critical spoken QSO data, whether in English or other languages. It's a challenging technical problem. My prediction is no less than 10 years until it is broadly available and sufficiently accurate. I could be wrong and we'll get there sooner, or much later! There is no financial incentive so we are dependent on technology developed in fields outside of amateur radio and, of course, dedicated and capable volunteers.

Digital

Digital modes are particularly amenable to automated spotting. It has been available for years through use of WSJT-X and similar apps in concert with services like PSK Reporter. One only needs to click a check box to report all that the software hears. The data can be retrieved and analyzed via online services, whether PSK Reporter itself or downstream services that utilize the data feed.

You can manually inspect what other reporting stations are hearing or use services that graphically present the data. Again, I am no expert on those services so I'll let you discover those on your own.

Even if you don't send your data to PSK Reporter, you will be found since most of the stations you work on digital modes upload their reception data. 

Contests

Spotting in contests is different. The major difference is that, for a big station like mine, you run most of the time. When you run you have nothing to spot. Not only that, the spots that do appear are less appealing. Certainly you want to chase multipliers and other contacts, but if you're in an assisted class you click on spots and so you have little to contribute to the community. That is, you are not spinning the VFO and spotting stations that are not already spotted.

If you operate unassisted you do not spot. It is true that some contests allow you to spot others but not see others' spots. However that's rarely done even when permitted by the rules. Operators just don't connect to DX clusters when they're not in an assisted class.

For an increasing number of contests it may be that most of your spots will be for yourself: self spotting, where the rules permit it. When you're running there's little else for you to spot. This benefits you and nobody else, but that's the nature of the game: you want to be found and others want to find you.

In CW contests the skimmers are so successful that I often turn skimmer spots off. The reason is that the flood of data is overwhelming and not necessarily useful. Early in a contest everyone is a new contact so the band map isn't needed. Later after many stations have been worked, I turn skimmer spots back on.

For the casual operator in a contest, you are more likely to be a consumer of spots rather than a producer. Considering the high activity level in contests that really isn't a problem -- you probably aren't adding anything that others, including skimmers, aren't already producing.

Tools

There are many tools to analyze spots in real time or near real time. Some are downloadable apps while others are web based. You can track DXpeditions, where and on which bands there are openings, get alerts for grids, countries and specific stations. Many are free. The data is also used for research, mostly amateur but some professional, to correlate with solar and geomagnetic data and refine prediction algorithms. With so many spot sources there is a lot of data available.

I've used a few of these tools though far less than many others. Since I am not in a position to make recommendations, I won't. You can find them and their champions through an internet search. I'll leave it to others to guide you if you want to pursue the topic.

Where we are

Like it or not, spotting is the way a large majority of hams find stations to work. Older hams may reminisce about the old days when we spent many evenings spinning the VFO looking for stations to work, or that elusive rare DX with an unpredictable operating pattern. Those days are gone and they are not going to return.

The truth is that all that VFO spinning was tedious and frequently fruitless. I recall the days when I left my 6 meter rig parked on 50.125 MHz during sporadic E season. The hiss of the receiver filled the house since squelch wouldn't trigger on weak signals. Don't try this if you're married or living with others! The discovery potential of FT8 and other digital modes is one reason it has large replaced CW and SSB as the mode of choice for the serious 6 meter DXer.

Skimmers do much the same for CW, discovering stations and rare openings that would otherwise be missed. Although there is less need to spin the dial, it is helpful to CQ into the aether from time to time for the skimmers to have something to copy. If nobody transmits the band is dead to humans and also to our automated listening devices. That at least hasn't changed.

6 Meters is Heating Up

It's said that sporadic E does better when solar activity is low, thus favouring the years surrounding the cycle minimum. With the solar flux falling maybe we'll get some fireworks this summer.

I've worked the first DX of the 2026 season. Nothing too exciting and nothing new, but that's to be expected with 150 DXCC entities worked on 6 meters; every new country is harder to work than the last. Of those, 140 are confirmed on LOTW, my only QSL route.

So far this May I've worked S0 and EA8. I've heard other countries including several in Europe, D2 and in the Caribbean and South America. Around the continent, I've worked stations in VE7 and W7 along with several stations closer in. I could work many more if I was interested in short haul contacts, which I'm not.

DX signals are weak and fleeting this early in the season. From PSK Reporter data I know that I've been heard in Europe. I have no contacts with Europe yet this year. The summer solstice, the usual peak of the sporadic E season, is still 6 weeks in the future. It will get better.

Despite the negativity often seen with regard to digital modes, 6 meter DXing is one place where FT8 shines. It is perfect for discovering and exploiting the brief intensification of ionization that transport signals between continents at VHF frequencies. You can't chat over FT8, and that's fine with me. I don't chat much over CW or SSB either since my interests strongly lean towards contests and DX chasing. I see no reason to have a conversation when 6 meter opens; I have other priorities.

To enhance my enjoyment this year I configured my station so that I can operate HF and 6 meters at the same time. My hope with this change is to catch openings earlier than I otherwise would. 

My usual SO2R contest setup is ideal for this. It's quite easy to do by moving the 6 meter antenna to the second radio (Icom 7600 & Acom 1200S) and using it with WSJT-X. The main radio (Icom 7610 & Acom 1500) is dedicated to HF. Both radios connect to the same PC, one using N1MM and the other using WSJT-X. 

To limit interference when I'm transmitting on either radio I switch in the contest band BPF on the 7610. I have no BPF for 6 meters. That will remain a low priority despite its potential benefits. I know fervent contesters that dedicate a radio and amp to 6 meters so that they can work sporadic E openings during contests. FT8 is easy to operate in parallel since it is slow and only requires the occasional click of the mouse. There are no audible distractions to the CW or SSB contest activity on the HF radio.

Although less powerful on high duty cycle digital, the solid state amp is near instant on versus the 3 minute warm up period of the tube amp. With such fleeting openings the rapid readiness of solid state is more important than another 1 to 2 db. I prefer not to keep the tube amp idling all day long, especially in summer when the shack is already too warm. When I buy another solid state amp later this year it will increase my flexibility, and power, in this activity and in contests.

Returning with the propagation are the 6 meter robots. They are growing in number. Unfortunately, WSJT-X-improved supports a blacklist of only up to 12 call signs. I wish it were larger. I find myself editing the list as robots appear to strike out the ones bothering me at that moment. It would be easier to add each of them once.

I don't really mind the existence of robots, I simply ignore them. The problem is that they fill the decode screen with their endless CQs that push the wanted DX signals off the messages received pane of WSJT-X. I have to scroll the screen to see what I might have missed. It is easier when I can just glance at the screen from across the room. So I filter them into invisibility. I find the behaviour of robot operators perplexing but it isn't my concern.

As always, don't be surprised or offended if I don't reply to you when I call CQ DX and you are not DX. It's nothing personal: you're not my intended audience. My primary interest on 6 meters is DX. I don't hunt grid squares, states or special call signs. One of the joys of amateur radio is that we can pursue our individual interests, together or separately, while sharing the same spectrum.

Enjoy the season. Soon the DX will be rolling in. If I get lucky a few new countries will fill my log this year. Working DX on 6 is enjoyable to me even if I work no new ones. I hope that you have success on 6 this season no matter your objectives or station size. If you've never given 6 meters a try, you should. Sporadic E season is the ideal time of year to take the plunge.

Another Rotatable Side Mount - 15 Meters

One lack in my station is a sufficiently strong signal on 15 meters into Asia, especially east Asia. While we cannot run Asian stations like our friends further west there is a rich vein of multipliers to be mined during major contests. I was reminded of this during the last All Asia SSB while running Japanese stations by how incredibly weak most were, barely a whisper above the noise. And this is from a quiet rural QTH.

The 5-element stack for 15 meters has a rotatable upper yagi at 43 meters and the lower yagi is fixed on Europe at 32 meters. Individually and together they are very effective antennas. In daily operating the stack can easily break pile ups with just 100 watts. To achieve stacking gain the lower yagi must become rotatable. That is never easy for side mounted antennas.

There are two possibilities: a swing gate or ring rotator for close to full 360° rotation, or a fixed side mount for about 130° of rotation. The first is not really necessary in my station since I have other yagis that can fill the gaps. It is also the more mechanically challenging of the alternatives. 

The latter method can work well if the 130° of rotation includes both Europe and east Asia. That I can do. The plot shows the approximate coverage for the 15 meter yagi's rotatable side mount.

Unlike the 40 meter Moxon, the 5-element yagi can't be reversed to double the azimuth coverage. That's okay for my situation on 15 meters so I followed the same design as for the first rotatable side mount. Deviations from that design are minor, to accommodate differences on the mounting location and the coverage objective. 

Last fall I picked up a used Ham-IV rotator and controller. It looked clean on the outside and proved to be in good condition on the inside. That's more than enough rotator for the weight and wind area of the 15 meter yagi. A swing gate would require a far heftier rotator to deal with the high torque of an offset load.

Since the weight of the yagi, mast and rotator bears on the lower strut, I used 4" × ¼" steel angle. It was scrap and rusted but perfect for the application. I cut a rectangle of ¼" steel plate with conveniently located holes that lined up with slots in the angle stock. This made a sturdy platform that put the rotator far enough from the tower to allow rotation from about 60° (through north) to 280°, just as I wanted. The slots permit a small adjustment range to align the rotator and mast bushing

The strut is strong enough to support my weight and even jump up and down on it, which I did to test it after installation -- I should point out that I don't weight much so be very careful about trying this yourself! Unlike the aluminum strut that I used on the other rotatable side mount, there is no need for a support cable to keep it from deflecting under load. If it becomes a problem later I can easily add it.

The LR20 guyed tower is popular in Canadian big stations while rare elsewhere. Mechanical details will therefore be of little interest for most readers. Nevertheless, the design and construction process can be applied to other towers. I keep a section of LR20 (10' high, 120 lb) in my workshop as a jig for jobs like this.

The first challenge is that I had to use a different tower girt for this side mount. There are two guy/support girts on each section. Due to the yagi's position the girt for the lower strut has to fit between the guy yokes and section splice bolts. Pictures will help so here are a few.

On the left you can see the two cutouts for the splice bolts. I cut the angle stock with an abrasion wheel on a circular saw. Since it's out of sight high on the tower it doesn't have to be pretty! I regularized the slots as well as I could and removed all sharp edges and points. The strut was descaled and painted.

The strut couldn't be centred on the girt due to the guy yokes. A short length of steel angle stock seats the strut on top of the girt. 3" ×⅜" aluminum angles are used as fore and aft clamps to the girt to keep the strut stable under the stress of the weight of the yagi, rotator and mast on the far end of the strut. The clamps are cut with peculiar angles to fit the insides of the tower legs. 

The rotator plate will be shown in a later picture. It is outboard of the strut to maximize the rotation range. They are joined by ⅝" grade 5 hardware.

The upper strut only has to deal with lateral forces. The 1.9" O.D. 6061-T6 pipe mast runs through a 2-⅜"O.D. schedule 80 pipe section, which is used as a bushing. This is identical to the other rotatable side mount that is currently used for the 40 meter Moxon. I considered a polymer bushing, which I have in stock, but that is more difficult to clamp to the strut without crushing the polymer. I took the easy path rather than fuss with a more elaborate design to accommodate the polymer cylinder. 

The upper strut pivots on the rear bolt to the girt. The outer end is adjustable with a threaded rod that runs through the strut and a bracket bolted to the back girt. While not very visible in these pictures the design is almost identical to the one for the other rotatable side mount (I provided a link to that article above). By swinging the upper strut and sliding the rotator plate on the lower strut slots the mast can be vertically aligned and rotated without binding. 

On the right you can see the boom of the yagi still supported on the original plate that is attached to the tower with pinch clamps. A chain holds the boom to the tower. That becomes the pivot for swinging the boom over to the mast. A pulley and rope support the boom on the rotator side of the tower (centre photo). With the chain and rope lightly supporting the boom, the boom truss and the saddle clamps of the existing fixed side mount are removed. 

With the yagi's weight fully supported by the swing the mast is lifted out of the rotator with one hand and the boom is pushed to the outside of the mast with the other hand. Then the mast is dropped back into the rotator, as seen in the left photo. Although a second pair of hands would have come in handy it wasn't difficult to do.

While not too heavy, it was still awkward to lift and level the yagi to permit attachment of the boom to the mast clamp. The front rope was pulled to raise the boom up to the clamp and tied off to the tower. A second rope was used to lift the boom within the confines of the chain. There is no risk of the yagi escaping during the operation.

Unfortunately the saddle clamps that I selected didn't fit the 3" boom. That was quite a surprise! Since it was time for lunch I left the yagi to bounce in the wind and climbed down. On examining the clamps on the ground I discovered my mistake: I had selected clamps to fit 2-⅞" O.D. pipe. The u-bolts fit but not the saddles.

Since I was out by a small amount I tried to fit the u-bolts through the 3" saddles taken from the old fixed mounting system. To my relief they fit. After lunch I took the mix of u-bolts and saddles up the tower and completed the installation of the yagi to the mast. I was lucky that I didn't need to machine a new mast clamp to accommodate the 3" saddle clamps.

With the yagi attached to the mast it was time to quit for the day. The rain clouds were getting very close. I kept the antenna pointed at Europe and reattached the coax. The clamps were not too tight so the yagi swung on the mast a bit in the high winds that accompanied the rainstorm. It was almost a week until the cold, wind and rain subsided and I could resume work. The remaining tasks included: boom truss, protective rubber bumpers on the tower, coax rotation loop, and alignment with the upper yagi for maximum stacking gain.

Wiring of the rotator was completed last fall when the struts were installed -- this and several other projects were supposed to have been completed before winter struck us early and more severely than expected. The motor phasing capacitor is encased in UV-resistant plastic and a barrier strip matches the 8 wires required for Hy-Gain rotators. 

Wire #1 for ground/common (on the left) is connected to the tower, thus eliminating one of the 8 wires. The phasing capacitor is connected to #4 and #8 to eliminate the need for those wires. Cat5 cable is used for the direction pot wires #3 and #7. The high current wires for the brake (#2) and the motor windings (#5 and #6) are 14/2 electrical cable. 

This is my preferred wiring method for Hy-Gain rotators with long cable runs, well over 100 meters in this case. It gets the job done for the least cost. Copper isn't cheap. Extra cables to support future projects such as this one were thrown into the trench when it was dug during the early days of COVID.

I am still experimenting with the rotation loop, as I will explain shortly. The photos show its current configuration. When the phasing lines from the stack switch were made I included a few feet of slack to ensure adequate length for routing around obstacles and other unforeseen issues. For the lower 15 meter yagi there is approximately 3' (1 m) extra, with most of that coiled at the stack switch.

To make a sufficiently long rotation loop the full length of the LMR400 phasing line was pulled down through the cable ties. Since this is semi-rigid coax the amount of flex during rotation must be limited. The present configuration accomplishes this. It took a few tries to get it tracking properly and ensuring that there was very little stress on the cable.. 

Note: In these and a few other photos you'll see a few seemingly out of place wires and ropes. Those connect and support the two halves of the boom truss during the project. It's no fun having to lean far out from the tower to retrieve a dangling cable and turnbuckle that can easily escape from one's hand. For most of my yagis I tie a short length of rope between the two turnbuckles in case of turnbuckle or cable failure. It's cheap insurance.

The yagi in the previous pictures is pointed at a bearing of approximately 45°. The yagi further down the tower is the lower yagi of the 20 meter stack pointing to Europe at a fixed bearing of about 50°. Due to the offset of the rotator the clockwise stop for the 15 meter yagi is approximately 55°. In the photo immediately above, the yagi is at its counter-clockwise stop, pointing almost west at about 275°. This is the rear of the yagi (facing east) with first director adjacent to the tower. The rubber bumper protects the tower and boom when the operator over-rotates the yagi. The Ham-IV has limited torque and so is easily stopped when it hits a solid obstacle without the risk of damage to the yagi or tower.

Yagi de-tuning with the director so close to the tower is minimal. Coupling interaction is minimum at element centre and maximum when near the element tips. There is in fact more interaction as the yagi is rotated towards north. The measured SWR barely budges. Gain is difficult to measure or model due to the structure of the lattice tower. Modelling that I've done in the past of similar tight coupling is encouraging so I choose not to worry about it.

Of greater concern is stacking gain over the rotation range. Previously, the stacking gain was optimized with the lower yagi fixed towards Europe. Since the rotator is offset from the tower centre, where the upper yagi is centred, the yagis can only be in phase in one direction. In all other directions the feed points are not vertically aligned. For the rotatable side mount the phases are also aligned when both yagi point to Europe. The question is then how much the stacking gain is reduced in other directions due to the phase error.

The top-down diagram demonstrates how the analysis was done. The red dot in the triangular tower's centre shows the position of the upper yagis' mast and rotation centre. The blue dot is the lower yagi's rotation centre. The red dot adjacent to the tower is the 0° phase point that is in alignment (main lobes in phase) with the upper yagi when both yagis point to Europe (northeast).

The circle shows how the phase centre of the lower yagi moves in relation to the tower and upper yagi as the rotator is turned. The phase offset is quite small when the lower yagi points north. Modelling shows that the gain reduction is less than 0.1 db. That's negligible. 

The misalignment becomes quite large when the lower yagi points west. The offset is approximately 5' (150 cm) or roughly 38° at 21 MHz; 150 cm is 0.105λ for the 14.3 meter wavelength; the phase calculation is approximate, not exact.

The elevation plots are overlaid to show the effect. Since the resolution is limited, making it difficult to see small details, I'll mention that main lobe's gain is reduced by 0.5 db. That's not bad. The greater impact is that the nulls between the multiple elevation lobes are shallower, pretty well disappearing at high elevation angles. In a contest that can be helpful since fewer signals will be attenuated when the arrival angle falls into one of those nulls. It is inconvenient to fiddle with the stack switch (BIP, lower and upper by mouse control) for every contact. 

While not shown, the lateral offset of the booms has negligible impact. This is unsurprising since the vertical alignment of the boom (when pointed in the same direction) has little to no impact on the formation of the far field pattern. I took a few minutes to confirm it in the model.

The lower yagi could be slid backward to improve phase alignment to the west. However that would unbalance the wind load, require adjustment of the boom truss, and require greater extension of the coax rotation loop. The last will be difficult. For my style of operating the improvement is not worth the effort. It is rare that I'd benefit from stacking gain to the west. When I do I can live with the 0.5 db deficit. 

Another potential benefit of sliding the boom back is that the first director would be farther from tower when the yagi point west (see above). On the other hand, the front of the yagi (third director) would come closer to the upper guy that is due west, as shown in the adjacent photo. The top guys descend at a sharp angle and this is a large yagi. That interaction could be worse than the one between the first director and tower.

As I finish writing this article there is still some tidying up to do. The most important is the forward boom truss for which the cable isn't long enough to reach the mast. Pieces of the turnbuckle unscrewed and fell down over the winter months and I haven't found them all. 

I am also contemplating replacing the aluminum mast with steel. While not serious, it abrades a little in the rotator mast clamp and bushing. I'll check it again before winter and decide whether to replace it.

Other than these minor items the rotatable side mount is done and I've already tested it to Asia on air. The results are encouraging. As with any combination of antennas like this, especially so they're so high relative to wavelength, there are times when the lower yagi is superior. The reason is that with many elevation lobes there is an increased risk of a signal's arrival angle falling into a pattern null. The more expansive stack arrangement gives me greater ability to deal with those signals.

Multi-band Antennas & Inter-station Inteference

When I first built this station I put up a few multi-band yagis: TH6, TH7, Explorer 14. When operating SO2R in contests I could not share these yagis since I don't use triplexers but I had enough antennas to get by. Over time these antennas have been displaced by mono-band yagis. The last of them, the TH6, is slated for removal later this year.

Trap yagis are inefficient but they can be very convenient for most hams since it is rare to have more than one tower, or one robust enough to support a "Christmas tree" of mono-band yagis for 20, 15 and 10 meters. Let's set that aside in this article to talk about interference between radios -- SO2R and multi-op contesting -- when using multi-band vs mono-band antennas.

Above are multi-band yagis from Optibeam, DX Engineering and Hy-Gain (clockwise from top left). Only the last has traps. However, non-loaded multi-band yagis suffer various gain and bandwidth deficits in comparison to mono-band, full-size yagis. Coupling among close spaced elements, even if each element is resonant on a single band, create many anomalies. The same is true for mono-band yagis placed too close together. 

In general, multi-band antennas are often high-Q, with narrow operating bandwidth, due to traps and other devices to enable resonance on more than a single band. Simple antennas without those devices can also be multi-band by exploiting harmonic behaviour. These include full-wave loops (resonant on all harmonics), dipoles (resonant on odd harmonics), and EFHW (end fed half wave) multi-band antennas that are popular with many hams that lack towers. 

Multi-element mono-band directive antennas like yagis may resonate on harmonics but they will not be yagis at those frequencies. Therefore they are potential interaction sources while not being useful at those higher bands. For example, a 40 meter yagi on 15 meters can behave as a resonant long dipole with a complex but largely non-directional pattern. It can seriously degrade the pattern of a 15 meter yagi quite far away, depending on their positioning; reciprocally, the 40 meter yagi will induce significant current from a 15 meter yagi and send it down the transmission line to the receiver.

This brings us to BPF (band pass filters). They are the almost universal choice for managing interference between radios in a contest or DXpedition operation with two or more stations. For the present I'll focus on the most common situation of one station per band and not on the more difficult one where there are in-band stations.

BPF are not a universal solution since there are things they can't do. Our primary concern is reception, where we want the BPF in the transmission and reception paths to minimize interference and performance degradation. It is important for the station designer to understand how BPF function to determine how they can be best deployed. For stations with high power amplifiers the interference can be far worse. In this case the placement of BPF between the rig and amp or between the amp and antennas can have substantially different outcomes.

Other station elements impact inter-station interference, either by enhancing the effects of BPF or rendering them ineffective. For example, poor port isolation in an N×M antenna switch. BPF are critical but are not by themselves sufficient to eliminate interference.

It must also be noted that BPF are not always necessary. I operated SO2R very successfully at QRP power levels. When the antennas don't strongly couple modern receivers typically won't overload from the 5 watt fundamental on a different band. You just need to select operating frequencies to avoid harmonics from the other transmitter. If the antennas are far apart you can even do SO2R with 100 watts, and I have done so. In both cases you must also avoid transceivers that generate unacceptably high broadband noise; there are a few notorious examples that I won't mention here.

For the rest of this discussion let's assume a station that requires BPF for acceptable performance. As noted, BPF are just one element of station design. Now consider the following case of a tri-band yagi.

In this example the receiving radio is on 10 meters while the other station transmits on 20 meters on a different antenna. Even if the transmitter BPF cuts the 2nd harmonic by 70 db it can't be entirely eliminated. It can still be an overwhelmingly strong signal on 28.024 MHz that may require the 10 meter operator to QSY. If the 20 meter amplifier has poor harmonic suppression and the BPF is between the rig and amp (low power BPF), the interference can be worse.

On the other hand, with appropriate protections it is possible to share a tri-band yagi, and to do so without destruction degradation of receiver performance. There are several manufacturers of triplexers and associated high power BPF that make this possible, but it can be very expensive. Yet it may be cheaper than another tower and yagi suitably placed and filtered. 

The diagram is from VA6AM's web site where he presents numerous options for antenna sharing and what can be expected with respect to performance. I know sharing can work since I've operated at stations with this setup. One cautionary note: don't try this with trapped tri-banders and high power! The traps are unlikely to survive 2 to 5 kW of combined power from up to 3 transmitters.

Returning to the previous example, the 10 meter station's antenna contributes to the problem. The tri-band yagi is resonant on 10 meters and will take that harmonic and deliver it to the amplifier. It will pass through the amp unattenuated (on receive) and be attenuated by the BPF. It would seem that disaster has been averted, but has it? There is more to the story.

The annotated Google satellite view of my station shows the south pointing TH6 in relation to the high band stacks, the 40 meter antennas and the Skyhawk tri-band yagi. Let's say the TH6 is used by the 10 meter station in our example and the other station uses the 20 meter stack pointing to Europe (northeast).

As already shown, the 20 meter station's 10 meter harmonic is loud but is otherwise not a serious problem. It is usually sufficient for the 10 meter op to QSY 5 to 10 kHz on CW -- more separation is needed on SSB due to the wider signal (~6 kHz for a clean signal on the 2nd harmonic). Despite the actions of the two stations' BPF, during last year's CQ WW SSB our team discovered a serious interaction that I had not anticipated or previously experienced.

The 10 meter amplifier tripped and went offline. The problem wasn't the harmonic, it was the fundamental 20 meter signal that did it. The full kilowatt on 20 meters on the stack pointing at the TH6 was unattenuated by the yagi since it is resonant on 20 meters. The 10 meter station's BPF, which in my case are low power BPF between the rig and amplifier, protect the receiver but not the amplifier.

Still surprised? Here is what happened. Quite a lot of power appeared at the 10 meter station amp's antenna port. It is clearly visible on the amp's power meter which, like many modern amps, measures power whether the amp is in transmit or receive (bypass). There were several 10s of watts displayed on the amp's power meter. 

In this instance the amp was an Acom 1200S. The amp's protection circuits saw this as unexpected power output during receive. It was interpretted as an amp fault, such as oscillation while in receive (standby). The protection circuit flags this when there is no corresponding RF power on the input (transceiver) port. It's a sensible precaution despite the aggravation it caused us.

Had there been a high power BPF on the antenna side of the amplifier the problem would not have occurred since it would block the 20 meter fundamental signal picked up by the tri-band yagi. Our options were to switch to a 10 meter mono-band antenna -- which passively rejects 20 meter energy -- or turn the Skyhawk tri-bander south and hope that it was far enough out of the 20 meter stack's main beam not to pose a problem for the amp. Fortunately both options worked, but it was inconvenient for the operator to deal with.

I've previously discussed why I chose low power as opposed to high power BPF for my station, so I won't repeat that here. With that as a given, my task is to minimize interactions using some combination of BPF, stubs and antennas. Stubs can greatly attenuate harmonics produced by amplifiers if that is a problem; low power BPF filter the transmitter's harmonics. 

Solid state amps are more likely to generate harmonics than tube amps. Hams tend to run amps hard and that can markedly reduce linearity. Tube amps are better at harmonic suppression when that happens since the output impedance matching network (usually Π or T) also serves as a low pass filters. The output transformers typically used in a solid state amp don't have that feature.

Since my objective is to have solid state amps on both operating positions in my station -- for contesting agility and guest operator convenience -- it is worthwhile to invest in amps that have enough headroom with respect to our legal limit so that they are less likely to be operated beyond their linear range. The 1200S may have to be replaced.

There is more that I can do with antennas to reduce interaction. As already noted, even a dipole is resonant on odd multiples. That also applies to mono-band yagis that are made with dipole elements. They will pick up substantial harmonic energy from other antennas even though they are not exactly resonant on the harmonics.

One good example in my station is the 3-element 40 meter yagi. Through extensive modelling I discovered that the pattern of the 15 meter stack could be severely distorted when point at the 40 meter yagi, which is on the popular European path. I used small capacitance hats to move the 3rd harmonic well outside the 15 meter band to solve that problem. A side effect is that the 15 meter fundamental signal from the stack is greatly attenuated in the direction of the 40 meter receiver when using the big yagi.

The reversible Moxon on the same tower is naturally non-resonant on 15 meters since the topology of Moxon elements incorporates capacitance hats. It is also true to a lesser degree for the more conventional Moxon rectangle. The XM240 and similar inductively shortened 40 meter yagis are the same. The only difference in this respect is that inductive loading lowers the 3rd harmonic resonant frequency while capacitive loading raises it. 

The XM240 works pretty well on 17 meters and the 3-element 40 meter yagi works well on 12 meters. Since I have no resonant antennas for 17 and 12 meters the designs of those loaded 40 meter yagis had an accidental benefit for operating on those bands.

Even the 30 meter delta loop shown at left has interesting interactions that prevent its resonance on 15 and 10 meters, which are close to the 2nd and 3rd harmonics. In the EZNEC plot above, the currents are for the delta loop excited at 28.5 MHz. There are two effects that are worth attention.

First, the location of currents can be quite complex at harmonic frequencies. In this case there is very strong coupling to the tower; it is less at 21 MHz but still quite large. For the interaction case we are more interested in the feed point impedance than the pattern. The SWR is very high on both of these higher bands. At 21 MHZ the impedance is around 210-170j Ω and 2+20j Ω at 28.5 MHz. 

Part of the effect is due to tower coupling but also the 75 Ω ¼λ transformer (cut for the 30 meter band). The transformer is approximately ½λ at 21 MHz and ¾λ at 28.5 MHz. Although in the last case it is approximately a ¼λ transformer, the loop's feed point resistance can be quite different on it harmonics. This is an excellent example of how a matching network can beneficially filter unwanted energy from other antennas.

This is only bad news if your intent is to use this antenna on other bands. I am not. It's potentially good news for antennas with "interesting" matching networks. Matching networks, other than transformers, are narrow band, typically working on just one band or a portion of a band. 

Antennas that are resonant on harmonic bands typically will strongly reject the fundamental signal since the feed point impedance, due to the antenna being quite short on the fundamental frequency, and the feed point matching network (gamma, beta, etc.) presents a large mismatch to the signal on a different band. For example, a 10 meter yagi with a beta match presents a high SWR to a received 20 meter signal. Checking the impedance on other bands of a few mono-band yagi models in my files confirms this.

While inconvenient, you can test what you have by making and testing a model of the antennas on other bands. Or you can climb the tower and measure the feed point impedance on those bands. A high SWR in this case is desirable because the antenna is unusable on those bands. This is exactly what you want for contesting. The time spent can be especially beneficial before an antenna is bought or built.

To conclude this long article, I'll give my thoughts with respect to my own station:

• No triplexers or high power BPF: It's expensive, but so is another tower and antenna. While not ideal, I will make do with more modest objectives for contesting using low power BPF. The TH6 is being replaced since, due to its placement, there is no good way to effectively decouple it from the 15 meter stack. Its replacement will be 20 meter mono-band yagi, and possibly 15 and 10 meter mono-band yagis on a different tower. Harmonic pickup will thus be strongly attenuated. The Skyhawk is far enough out of the stacks' lines of fire (west of the big towers) that it doesn't suffer the same ills.
• Stubs: I've been planning to experiment with coax stubs to better deal with amplifier harmonics (I use low power BPF) but haven't gotten around to it yet. That may be enough to solve the few remaining interaction issues I experience, especially on CW where you often find yourself on the other station's harmonic. These must be switched and installed at both stations' amplifiers. 
• Transceivers with high blocking and mixing dynamic range: Direct sampling receivers like on my Icom 7610 are susceptible to overload that can be somewhat ameliorated with its internal filtering option. Superhet designs are still typically more resilient than direct sampling receivers. The advantage is gradually diminishing as SDR technology evolves.
• Situational awareness: Understand the potential for interference from the other station and each station's antenna choice, then avoid those situations. You might think this is easier when operating SO2R than in multi-ops since I know the station well and control all choices, but it's really easy to make mistakes in the heat of high rates and frequent band and antenna changes. There's a lot to keep track of. 
• Polarity: Antennas with opposite polarity interact far less than those with the same polarity. It is for this reason that multi-ops will use verticals for their in-band stations. I haven't done this yet in my station but I may yet do so if I get more serious about hosting multi-op teams. Keep in mind that the often quoted 20 to 30 db of polarization attenuation is an exaggeration. Relative positioning, induction in various structures and squint angle can reduce attenuation to 10 db or less. 

Decades ago I did many multi-op contests using kilowatt class amps without BPF or stubs and we somehow survived. The receivers didn't always survive so we kept spares on hand. Repairs weren't difficult with those simpler rigs, often no more than replacing a neon lamp: the so-called lamp fuse. Mostly we just argued about who should QSY when inter-station interference became a problem.

No matter your contesting objectives, hopefully there are a few useful ideas in this article. There is a wealth of data out there if you want to do a deep dive into the topic.

Springtime Lull

The bad spring weather continues. This has been the wettest early spring I can remember for perhaps 10 years. At least it has warmed up, although we still have regular cold weather. That isn't so bad except that it comes with high winds and snow. It is always amusing to see the tulip shoots pushing up through the snow cover. This weekend it was a summery 25° C on Saturday and snowing on Sunday.

About the only productive work I've done outdoors was several hours clearing brush along the Beverage lines in preparation for summer growth, and to take down several large dead maples that threatened the towers or buildings. Felling trees isn't so hard but cutting them up and disposing of the debris is a lot of work. I also spent time putting connectors on and testing Heliax runs that I hope to bury in a trench to one of the big towers either this spring or in the fall.

I did manage one tower climb to resume work on one of my projects. That was great until I fired up the station for the Ontario QSO Party and found out I had trouble with both prop pitch motor rotators. One wouldn't turn at all and the other had an intermittent direction pot.

Remember this uncomfortable truth with large stations: you can be as thorough as you like yet there are so many things that will go wrong. Maintenance is never ending, no matter how well you build it.

I've had time to operate yet admit to doing little. General chatting doesn't often interest me and there has been little happening on-air to attract me. I've been passively monitoring far more than I've operated.

• There are no interesting rare DXpeditions at present. 3Y0K brought excitement for a while and then there were S21ZD and XX9W, plus a few others that drew my attention. The latter were difficult due to being shots over the north pole. They seemed to have more luck with Europe and with FT8 so that's what they did. 
• Despite that difficulty, with daylight shining on the Arctic there have been regular openings most evenings to Asia over the pole, at least on 20 meters, and some on 17. The several days long dive of the solar flux below 100 bodes ill for 15 and 10 meters. The years long slide down to the solar minimum is well underway.
• 
  6 meters briefly showed signs of life around the spring equinox, as expected. I heard South American stations almost daily for nearly 3 weeks. That dried up in early April. In any case there were no new ones to work. There was a CE0Y station active but not on 6. It will be several weeks yet until we see the first glimmerings of the summer sporadic E season.
• 160 meters has been quite poor. Most evenings the Europeans are very weak. Even the FT8 activity is subdued. There has been little DX at our sunrise openings, just the occasional VK and KL7, with just one JA heard on FT8. I expect better with the quiet geomagnetic conditions at present. As previously mentioned I heard but did not work 3Y0K on top band. I could have tried harder but it was inconvenient. Soon I'll be rolling up the radials for the duration of the farming season.
• There are no major contests. The next is WPX CW in late May, which I may enter for practice since it's not one that I particularly like. The only QSO parties that interest me are the Ontario QSO Party, where I want to raises the activity level, and perhaps the Florida QSO Party since it is one with lots of activity. Handing out a mult was fun in OQP but the contest was otherwise not terribly exciting.

While the rain pours and the winds howl, keeping me off the towers, I am dabbling with various indoor projects. 

• 
  I made significant strides on the software for the next version of my antenna selection software. Although it won't be ready for a while yet I am getting close to connecting the new UI (user interface) to the Arduino-based antenna switching system. The design process has been interesting since the revised UI requires a different relationship between clients and server. I may write about it when the project is done.
• To support the antennas slated for construction this year and next I am preparing Heliax runs to the tower that hosts the 20 and 15 meter stacks. That tower also has a 30 meter delta loop and the tower itself is shunt-fed for 160 meters. A new trench will be required, running parallel to the one I dug 6 years ago. I'll toss a Cat5 cable into the trench for control line expansion.
• Most of the material for the new 3-element 20 meter yagi has been assembled. I'm thankful that the aluminum is on hand because, have you see the price of aluminum recently? Antenna prices are going up, commercial or home brew. It ain't easy being a big gun!

This article took me so long to finish that I finally did spend a few hours on the towers. Many more will follow as the spring weather stabilizes. I'm beginning to realize how much work there is to do this year. I'm getting exhausted thinking about it. The springtime lull won't last much longer. Then, if I feel lazy, I'll have different excuses to avoid work on the station, such as ticks and the growing hay.

Stray Capacitance in Interaction Models

Measuring stray reactance -- L and C -- can be difficult because the values are typically quite small. Yet that is a requirement I've dealt with when modelling antenna interactions. Test fixtures can only be built with some difficulty and then measured with suitable instruments, and I've never done that before. The literature addresses some of the cases I run into but not all. Then there's the matter of whether the quoted figures are reliable since the measurements methodology may not be described.

There are two cases in particular that I want to discuss since they are prevalent in my station and I've harboured doubts about my methods and calculations:

• Coupling of guy cable segments at insulators. There is coupling due to field interactions (naturally dealt with in NEC engines) and the series capacitance of the overlapping guy grips.
• Coax common mode leakage across transformers with galvanically isolated windings. I use lots of these in my Beverage systems, and I use more in long runs of RG6 lying on the ground that may be parallel to Beverage antennas for some distance. 

When I first developed interaction models in EZNEC for my guyed towers I modelled a wire for each non-resonant guy segment and overlapped by a length and separation approximately that of what was built. That was cumbersome and not really very accurate, but probably good enough. For the small Beverage transformers I represented the coax with connected wires and placed series capacitive loads on the wire to model the series capacitance between the transformer windings. I used values gleaned from ON4UN's Low-Band DXing and other sources.

The latter method of modelling stray capacitance is easier than the former, so I've been using it almost exclusively for the past several years. However, I don't know how accurate either method is or can be.

It struck me as an ideal small project to tackle during the extraordinary and persistently bad weather we're going through this April: rain, snow, wind, cold. There are always jobs to do in the shack and the workshop when tower work is too uncomfortable. I set out to measure the series capacitance in the cases listed above with the hope of designing better interaction models in the future.

I have a 1:1 Beverage transformer on a BN73-202 binocular ferrite core with 3 turns of insulated #26 wire for both windings. It was left over from a project and is identical to what I use for isolating coax segments in my long RG6 runs to the Beverage antennas. For the other case, I quickly constructed a "dummy" guy segment termination from a 504 insulator and two 5/16" guy grips. This is what I use on my big towers supporting stacked yagis and large 40 meter antennas.

There are 3 instruments that I have available for the measurements:

• RigExpert AA54 antenna impedance analyzer (single port)
• VNWA3 2-port VNA
• 35 year old LCR meter (made in Taiwan, and the brand is defunct)

I first did the measurements with the AA54. The results, at first, seemed sensible, but did not pass scrutiny. This shouldn't have been a surprise since these analyzers, even one of this quality, have increasingly poor accuracy as you move farther from its 50 Ω reference point. A pure capacitance in series with an infinite resistance (open circuit) has a very high SWR indeed. It is a poor LCR meter in these circumstances.

You may have to click on the image to improve the resolution. On the right are two measurements of the transformer, one open and one with the transformer in circuit. The ends of each winding are joined for the measurement of inter-winding capacitance. I compared the two calculated capacitance values with the expectation that their difference would be close to the actual value. In this instance, the difference fell between 2 and 3 pf: measurement precision is no better than 1 pf.

Notice that the R value is 0 Ω for all of the measurements. That casts suspicion on the results. The open circuit is so out of bounds from what this single port device can accurately measure that some deviation was to be expected. The measurement of the guy cable series capacitance is about the same, further casting doubt on the suitability of the instrument for this application.

I tried the measurement from 1 to 50 MHz in the hope that there would be an island of stability, if not accuracy, at least at low frequencies. At low frequencies the calculated capacitance was far too high, only stabilizing above about 5 MHz. So I chose 50 MHz and got the same result at a few other randomly selected frequencies. The poor accuracy really isn't the fault of the antenna analyzer. I asked it to do a job it was not designed for. 

I moved on to my old and trusty LCR meter. Like most of these instruments it does its measurements at a low frequency, although that is not documented. But I have had a lot of success with it over the many years I've owned it, measuring fixed and variable capacitors from a few pf up to a large fraction of a μF. A major downside of the meter is that it eats through 9 volt batteries very quickly.

The LCR measurements were quickly done with the aid of the short alligator clip leads. The stray capacitance of the instrument plus leads is slightly below 6 pf, so we subtract that from the measurements.

The results are far more in line with my expectations: 5.6 pf for the transformer and 11.3 pf for the guy termination. The Xc at low HF frequencies is close to what others have measured for a transformer of this design. That gives me confidence that these values improve my interaction models. Greater measurement accuracy may be desirable for capacitors used in antennas and matching networks.

I did not do measurements with the VNWA 3 at this time. With the many recent PC upgrades I made this winter it would take some time to set up the software to use it. The single port (S11) measurement would likely be better than with the AA54 but probably not by a lot. More accuracy requires a 2-port (S21) measurement of the series reactance, using a fixture that includes the outer coax conductor. Maybe when I have nothing better to do at a future date I'll make the measurements if only to satisfy my curiosity.

In practice there are many parameters that determine guy wire interactions, with the series capacitance just one of them. As you go higher in frequency the Xc falls enough that there is significant conductance through those guy terminations. For example, Xc of an 11 pf capacitor 30 MHz is just 480 Ω. It's 10 higher on 80 meters. Those non-resonant guy sections are not as isolated as they appear! Don't be surprised if they model differently than you expect when you include the stray capacitance between supposedly non-resonant guy segment.

There are also induced currents from the antenna itself and among the guy segments despite each segment being non-resonant in isolation. Perfection isn't possible: we can only do the best we can. I intend to use the LCR meter measurements in my EZNEC interaction models until I have better.

Is it worth the effort? I believe so. I've put enough years and sweat into my "big gun" station that it is only sensible to get the most from it. That doesn't mean I'll make major changes when an interaction is worse than I'd like, but I'll know what to expect. That's valuable information even if it isn't good news.

Ignorance is not bliss. 

Did FT8 Save Amateur Radio?

It was with some surprise that an article I wrote a few months ago went "viral". Well, viral as far as it can be within a limited population of hams. It has been the most popularly viewed article in the recent history of this blog. 

Digital modes court a range of emotional responses from hams that have been licensed for a long time. Newer hams just shrug and carry on. Digital is undeniably popular. Many of the public comments and private feedback to my article seem to have missed the point. I was drawing attention to the way the world is, not the way any of us might wish it to be. So, yes, digital has won. You don't have to like it.

At the risk of being seen as taking advantage of the controversy I will revisit it for a particular reason. It isn't for the financial reward since I get none from the blog. That reason comes from a throwaway comment made by a friend when we spoke recently. That's the source for the title of this article. We laughed it off, but I kept coming back to the question over the following days. 

It's worthwhile to flesh out the arguments pro and con. I might as well since I am unable to get any tower work done due to weeks of poor weather. The above photo was taken this morning. I envy those of you that don't experience spring snowstorms. Warm weather is on the way so technical articles will follow as I start into my long list of tower and antenna projects.

First, what if there were no FT8? What would have been the implications on licensee numbers and on-air activity? There is no way to know for certain. Instead we have to look at the evidence that exists, circumstantial though it may be.

Let's review a few facts, not all of which have hard data attached. I am not willing to invest the time to do extensive research for a brief article like this. Hopefully there are no significant errors:

• There are more hams in the world than ever before. It is certainly higher in Canada, the US and many Asian countries other than Japan, growing at rates faster than the total population. It may also be true in Europe, though not so much elsewhere.
• Towers for effective HF communication are being eschewed by new and young hams in developed countries for a variety of personal and societal reasons. That was not true decades ago. They prefer simple antennas, portable operation (e.g. POTA) or may avoid HF entirely.
• Few new licensees know CW and only a fraction of them learn or are planning learn. Yet phone and conversational digital modes can be difficult for those with small stations. Like long time hams, there is more interest in making contacts, DX or otherwise, than having conversations. Conversations take place off-air, even among hams.
• VHF/UHF FM is the gateway for many new hams, for local communication, public service and emergency preparedness. Many of them let their licenses lapse. A few of those that stay migrate to HF. 

It is a commonly held belief by many older hams that if there were no digital modes that new hams would be active on (what they like to call) "human modes." That is, where a computer is not an active component of the QSO. This mainly is meant to mean CW and SSB, although some will include RTTY and other computer encoded/decoded modes that permit conversations or data communication.

Is that true? We can only speculate since there is no way to do an experiment. Take a look at the waterfall spectrograms shown in that earlier article that caused such a fuss. Do you believe all those FT8 signals would transfer to CW and SSB if we auto-magically and retrospectively eliminate digital? In my frank opinion, no, that would not have happened.

There are few conversations taking place on HF. Most are "599" DX QSOs or POTA activations. Those that are actual conversations are between hams of long acquaintance who have a regular schedule or participate in so-called nets. If we restrict our focus to CW there are even fewer conversations, and those are typically not between or with new and young hams.

CW won't die but it will become a niche mode. SSB will continue since it is easy. Few new hams that are solely on FM will stick around, or will find their niche there and stay there.

Digital modes, FT8 in particular, are undeniably popular. New hams with small stations can work a lot of DX on HF, and they do! They really enjoy it and have been bitten hard by the DXing bug despite the naysayers. It doesn't interest me as a contesting mode though some promote it as such.

That said, is there an attraction for a digital-exclusive HF operator to spend more time on SSB and to learn CW? The answer is yes. Many are learning CW to improve their POTA results, mix it up in the pile ups and to become more versatile contesters. It has been said (and I agree) that CW is an ideal contesting mode.

Of course, many of those using digital on HF are unlikely to ever learn CW and they are discouraged by attempts to DX with SSB from their small stations. We are well below replacement numbers on CW, so its use will decline as elderly hams depart. It has had a wonderful 100 year run but now its time has passed. SSB will continue as a DX and contest mode and for some conversation. FT8 will likely be a mainstay for general operating and DXing on HF for many years to come. However, we can't reliably predict far into the future. Time will tell.

I've droned on for longer than I intended. But it's relevant to the original question: did FT8 save amateur radio?

If we restrict ourselves to HF, I am leaning towards yes. I'm not convinced but I am persuaded. Had there been no FT8 (by far the most popular digital mode on HF and VHF) those hams currently active on FT8 would not be on CW or SSB. The spectrogram of a CW band segment like that in the earlier article would likely look very similar.

That's not the end of the story since FT8 does more than just increase activity at 7074, 14074 and the other FT8 watering holes. Once these hams get hooked on HF, DX or POTA, their ambitions grow. Many hams new to CW and SSB have migrated after being almost exclusively on FT8. SSB first, of course, yet many are learning CW. Why? What incentive do they see?

The answers are various, with no one overriding reason. The following are ones I've personally heard from newer no-code hams. Keep in mind that these observations do not comprise a statistically valid sample:

• The challenge of learning and becoming proficient at the code
• Improve results in radiosport activities: POTA, SOTA, DXCC and contests
• The high rate potential in competitive contesting
• Relatively simple home brew CW equipment for the technically oriented

Communication isn't in the list since that isn't the attraction in 2026. It seems to only attract a minority of new hams. Again, it isn't about what ought to happen (however you may feel about it) but what is happening.

There is a story in the current (April-May 2026) issue of the National Contest Journal about one relatively young ham, WM6Y, who took the CW challenge after spending time on FT8. You have to be an ARRL member to read the article so I will quote a few sentences:

"Do not dismiss digital modes. They can be a gateway, not a replacement. Sometimes the path to CW does not start with a key. Sometimes it starts with a computer screen — it did for me. FT8 brought me back to amateur radio. It motivated me to upgrade my license. It led me to portable operations and ultimately to CW. Without FT8, I might never have returned to the hobby at all."

In his case the activities were POTA and contesting. That agrees with my experience talking to newer hams, as I mentioned above.

Digital isn't so bad, so cheer up. These modes can contribute a great deal to the future health of the hobby, whether or not hams decide to later migrate to CW and SSB. I regularly use FT8 on 6 meters and a few other cases, despite initial reticence. I guess you could say I took the opposite migration path: from CW to digital. 

The future is potentially bright for our beloved hobby, and digital may be an important reason why.

CQ WPX SSB 2026

I did not operate the WPX SSB contest. I don't particularly like it and I said why in an article many years ago. There is no reason to repeat any of that here, so read that article if you want to know why. Indeed, I've provided other reasons in articles before and since. Search the blog if you are interested. This is not to say it's a bad or problematic contest! This is about my personal preferences; many of my acquaintances feel the same.

I was therefore happy to make my station available for another contester to operate the WPX SSB contest this weekend. Shel VA3AA took up the challenge. He's operated here a couple of times before, most recently in ARRL DX SSB. This was a learning opportunity for him, to put in a lengthy 36 hour effort and make tactical decisions as a single op rather than as part of a multi-op team.

Conditions were reasonably good. His raw score was a very respectable 7.5M, including more than 2400 contacts and just shy of 1000 prefixes. There were times he was frustrated and times when things went wrong. Yet in the end he left Sunday evening with a big grin on his face. He is certain to do better in future contests. Contesting is a skill that can take years to perfect.

I made myself available for the entire weekend to resolve station problems and to help him make the best use of the station. Having many antenna choices is both a blessing and a curse: there is a lot to deal with. From time to time we discussed operating tactics and techniques. Those of us who have been in the game for a long time often don't realize how much there is to learn before we become proficient contesters.

Big stations run a lot in this contest, especially in the early hours. The reason is that there is little need to chase multipliers when almost everyone is a multiplier. But if everyone runs there is no one to work. It can be a good strategy to hunt stations at first rather than run since the rate can be better. Soon, though, you have to run if you're to do well. Happily that is effective with a big station like mine. Stations running low power or QRP have a more difficult time in WPX than in many other major contests.

Despite its importance, getting too comfortable with running can work against you. It is vital to frequently switch between running and hunting to maximize rate and multipliers. When the run rate isn't what it should be, switch bands or make use of the second radio to hunt stations. With SO2R capability it is generally advisable to always run on one radio and hunt on the other. For the proficient, there is 2BSIQ. In WPX, hunting on the second radio is usually the better strategy for most competitors.

SSB SO2R is more challenging than for CW or RTTY. Call signs at the very least must be voiced. For a variable exchange (serial numbers in WPX) the challenge is greater. At the very least it is important to use voice messages (CQ, Thanks, call sign, repeat please, alternative call sign phonetics, etc.) to save the voice, avoid unnecessary improvisation and leave your voice free to speak on the second radio. 

TTS (text to speech) and related voicing technologies are increasingly being used to make SO2R and 2BSIQ almost as easy as on CW or RTTY. It is in its early phases and implementation is not yet easy. It is already available as a feature in N1MM Logger+. Not everyone approves of the new technologies, but don't let that dissuade you. It will become routine and universal before long.

I have never seriously operated SO2R in phone contests. I have the basic capability but it was mostly untested. It took some effort to configure the station to switch message playback and microphone to the appropriate radio. Foot switches for each radio are useful, or VOX can be used, however these only work if the software switches transmit focus accordingly. Operator action is required to ensure the routing of the mic is correct. 

I am mostly familiar with N1MM, and it does phone SO2R pretty well once you climb the learning curve. It's a skill that competitive contesters need to learn. I did the setup but Shel had to practice doing it effectively. Now that it's working I'll probably use it more myself.

Agility is critical in any contest operation, and can be especially important in WPX. You have to run but when it doesn't deliver results you have change something. The station must enable agility so that the operator is not inhibited. For example, having to tune amplifiers on band changes, large frequency excursions (e.g. clicking on a spot) and changing antennas, discourages the operator from adjusting tactics on the fly. Although it may not take long it is a burden when every second counts. 

I am planning to acquire a second solid state broadband amp this year and to increase the availability of antennas with low SWR across the bands of interest. This will be a busy year if I'm to be ready by the fall contest season. There is also the rewrite of my antenna selection software (user interface only) to improve the visibility of available antennas, their selection and direction control for rotatable yagis and steerable fixed arrays. That project is ongoing but unlikely to be completed for several months.

There were technical issues, as is typical for a large station with so many potential points of failure:

• We courted disaster a couple of times because my home brew prop pitch motor controller doesn't check for over-rotation. I put off development of that feature until a future version, which may have been a mistake. Operators (including myself) are almost certain to forget whether, when pointed south, it got there in the clockwise or counter-clockwise direction.
• The Icom 7600 is known to have a power spike when the transmission begins. It doesn't happen often and it is notoriously difficult to measure. The Acom 1200S protection tripped numerous times during the contest. The only solution is to replace the transceiver. I may do so this year for this and other reasons.
• The TH6 is tuned for CW and therefore has a moderately high SWR at the upper ends of 20, 15 and 10 meters. That made the antenna almost unusable. Plans to replace the antenna (which is fixed south) are proceeding.
• The 40 meter reversible Moxon does not function in the reverse (south) direction. That made it difficult to work as many US stations as are necessary in this contest. Wintery weather has made repair impossible. I hope to get it done in April. Nevertheless, Shel found that it worked quite well since the F/B is fairly poor above 7200 kHz.
• SO2R Mini switching of the mic input occasionally misfired. It could be fixed with a software reset but that cost time. It's time to upgrade the firmware and hope that solves the problem. Having not done mic switching before I was unaware of these issues before Shel encountered them.

Back to the contest, Shel found that it was difficult to choose off times and focus geographies based on activity levels. Single ops only get to operate 36 out of the 48 hours, making the choice of off times very important. The same is true when operating in the Classic overlay category (24 out of 48 hours). Make the wrong choices and your score will suffer -- don't prioritize personal comfort over operating schedule if your objective is a high score.

Conditions were pretty good for the contest duration, or at least consistent and predictable. We are late enough in the season that 10 meters was poor on the important NA to Europe path, and 15 was poor the second day. The noise level on 80 meters was higher now that spring weather has arrived. 40 meters was, as usual, a zoo on the SSB segment. Running meant staying below 7125 kHz for DX and above 7200 for the US to avoid the din between 7125 and 7200 kHz. Of course many Americans called when Shel was outside the US phone band and Europeans called when he operated above 7200 kHz. Too many operators do not pay attention when chasing spots.

When DX conditions are poor we have the large population of the US nearby. That is not as useful as in years past since contest activity in North America has declined. The decline, while not large on phone, has a noticable impact on scores. There are records established years ago that may never be beat. Setting those as an objective can lead to disappointment. Whether propagation or activity, a contester must adjust his or her tactics to deal with what we have to work with.

After so much negativity I should admit that I'm tempted to enter WPX CW in late May. If nothing else it will be an opportunity to practice my SO2R skills. I typically don't care for contests in the warmer weather so this exception might not happen if the weather is particularly fine that weekend.