Monday, February 28, 2022

ARRL DX CW Contest (2022)

I occasionally recap my contest experience to relate events and to discuss topics that may interest others and not just me. The 2022 running of the ARRL DX CW contest is one of those. I'll try to keep it concise to avoid boring readers who have not been bitten by the contest bug.

Choosing a category

It has to be said up front: I have no illusions about winning. These days I am up against the big guns, often with even bigger stations, better propagation and better operating skill. When I choose a category I try to balance testing the station, testing myself and having fun.

Due to technical problems I was at first reluctant to operate in an all bands category. One temptation was 40 meters single band, assisted, to put the new antenna to the test. I could also rest during the day and avoid the drag of a 48 hour marathon. This worked well for in CQ WW SSB last fall when I entered the 15 meter assisted category.

With conditions good and a positive attitude I decided to see what I could do with an all band effort. I demurred going assisted to focus on improving my running skills and test the potential of the new 40 meter yagi. I believe I made a good choice, although it's likely I'd have been happy regardless of my choice.

Run versus hunting multipliers

I have a tendency to linger too long when attempting to work multipliers since I'm a passionate DX'er. This is where the logging software helps to give you perspective. I use N1MM+. On the score summary window there is a statistic at the bottom that tells you the incremental value of a multiplier. For example, it might say "1 Mult = 5.5 Q's". That is, the score will increase the same amount by working one new multiplier or 5.5 QSO's (of average point value).

If you are a big gun it can pay to keep running and not hunt multipliers. It takes time and effort, even if you are assisted. The potential value of hunting multipliers is reduced by the fact that a big signal attracts many callers, including new multipliers. When the running is good it is often best to keep at it.

Big guns benefit from hunting, and the experienced operators know it. When there is a brief opening to a difficult area of the world to work -- for us, that is always true of southeast Asia -- taking time to sweep for those multipliers or to call CQ while pointed in that direction pays dividends. When the bands are closed to Europe -- for us, that is mid-afternoon at this point of the solar cycle -- the runs slow considerably and the time may be better spent multiplier hunting.

For whose doing SO2R, it is possible to hunt while running. Indeed, that may be preferable early in the contest when running on two bands (2BSIQ) can be difficult because of the size of the pile ups.

For those with low power or small antennas the choice more often favours multiplier hunting. Every situation is different and you have to continually assess whether to stop and run rather than keep hunting. When I had a small station I would try to run at intervals and stick with it if the rate was acceptably high. Otherwise I'd return to spinning the VFO. Now I am far more likely to keep running when conditions are favourable.

2BSIQ

Running concurrently on two bands is a difficult skill to learn. Most SO2R operators run on one band and S & P on another. However when it's done well and you get into the "flow" it can be tremendous fun and your score will grow at an impressive rate. I have had SO2R success in contests like NAQP but not the major international contests. The reason is interesting.

In NAQP a large majority of stations run 100 watts. That narrows the range of signal strengths of callers, and signals are usually not exceptionally weak. When I run a kilowatt on a band with QRN and QRM there are many weak callers. The "rhythm" of 2BSIQ is lost and bedlam ensues. 

For example, the late night opening on 40 and 80 meters (after their sunrise) only lasts 1 or 2 hours, so it is very productive for 2BSIQ. Unfortunately, the many callers and their low SNR requires concentration to separate one signal from among many and to copy them well. I ultimately failed at the attempt. It would go well for a while and then I'd get a large burst of callers on one or both bands and I'd lose control of the timing and end up with pile ups raging in both ears. Half the time I'd abandon one of the run frequencies to regain control of the situation.

Saturday on the high bands the rate of European callers is high. My full attention is required to run on one frequency. Running on two bands is beyond my ability, so the second radio is only used for S & P if at all. On Sunday when the rate is lower it is a little easier to do 2BSIQ on 15 and 20 meters. But for me it is remains difficult. All I can do is keep practicing.

Automation and equipment woes

The bigger the station the greater the number of things that can go wrong. There is always something that needs repair or maintenance, or there are projects still incomplete. My rush to get the 3-element 40 meter yagi finished before severe winter weather arrived put many other jobs on hold.

Here is a selection of the equipment challenges I faced during the contest:

  • The prop pitch motor turning the upper 20 and 15 meter yagis does not work well or at all in cold weather. By that I mean below 0° C. In our climate that's a huge issue. Since the weather during the contest was typical for February I parked the yagis to 330°, at east Asia, and used the lower yagis to work Europe. The stacks were never in play during the contest.
  • The rotator for the side-mounted TH6 was stuck. I had parked it at its west stop to protect it from wind storms and it appears that the Ham-M brake wedge would not retract. On Saturday it freed itself, much to my relief. Due to the prop pitch problem, the TH6 was the only antenna for 15 and 20 that I could turn to the west and south. 
  • Lack of automation causes a "fear and loathing" of  band changes. Each band change requires switching antennas, switching the BPF, switching the amp and tuning the amp. There are no rapid band changes to sweep for multipliers or to check propagation. For quick band changes I left the amp offline and operated without the amps.
  • Lack of good visual indicators such as LEDs caused antenna selection errors. For example, I inadvertently used the low XM240 rather than the 3-element yagi on 40 meters to run Europe Saturday evening. I was struggling but didn't discover my mistake for 2 hours.
  • Despite the BPF, the FT950 receiver cannot deal with a few band and antenna combinations. There is enough RF from the other radio and amp to cause excess noise and make SO2R difficult. Turning off the pre-amp helped but on the high bands that affected copy of weak stations.
  • A series of unexpected strong wind gusts on Sunday turned the 3-element 40 meter yagi by 10° on the mast. I believe this was caused by an unfortunate mistake during installation. It is easy to repair. The storm also damaged one element, and that repair will be more difficult. However the antenna continues to work very well so it's more of an inconvenience for now.

Once the warm weather arrives I have a long list of maintenance tasks to deal with. I no longer have the excuse of major antenna projects to distract me so I'll just have to get down to work. The same goes for progress on station automation. I expect to be in far better shape for the next contest season.

40 meters

The new 3-element yagi worked well. One glitch was due to my poor switching system, whereby I was on the low XM240 for a couple of hours by mistake. I wondered why my rate wasn't what it ought to be during the European opening!

Over the pole it brought in welcome multipliers from Asia. I even managed a brief JA run after our sunrise. This experience bodes well for the future. One dark spot is that the antenna suffered minor mechanical damage during house-shacking wind bursts Sunday afternoon.

Remedial work will be done when the weather warms up. For now the antenna continues to work well despite the problems. Details will be left for a future article.

QRL?

In the heat of competition many contesters searching for a run frequency on a crowded band fail to first ask "QRL?" or even to listen for a few seconds. Only a few of these are deliberately attempting to steal the frequency. It is too easy to be trigger happy in a fast paced contest: you listen for a second or two and start up the CQ machine. Others see a hole on the SDR spectrum display, click and punch the CQ button. 

Almost all will QSY when I announce my presence. The reason for the silence that entices them is usually that I'm listening to a weak or slow station, probably one within their skip zone that they cannot hear. This is mostly a high bands problem since the crowding is less and the skip zones smaller or non-existent on 80 and 160 meters.

A related problem is for stations within my skip zone. That includes a populous region of the United States. Unless we hear each others' callers it is easy to believe the frequency is open.  We can't hear each other so we don't copy the "QRL?" We may not realize what happened until we hear the confusion of callers. The frequency isn't big enough for the two of us so one of us must go.

Propagation

Experienced contesters check propagation paths a day or two before a major event. Admittedly I don't often do it but this time I did. It helped me to plan and to ultimately select my category. 

RBN (reverse beacon network) is a valuable tool since listening for stations and calling CQ are not enough. Outside of contests few hams appear for these brief and unusual openings. I call CQ hoping for a reply, but I will settle for data from the RBN. Unfortunately there are few nodes in Asia, Africa and Oceania, and those are critical to propagation research. Despite that lack the exercise is valuable.

One example is the path to northeast Asia during our early evening and their post-sunrise morning on 15 and 20 meters. The prospects for good openings were promising and indeed there were productive JA runs during the contest at the predicted hours which had been rare during the solar minimum.

Another propagation path that is particularly valuable in the ARRL DX contests is Europe on 80 and 40 meters after their sunrise. When the geomagnetic field is quiet the opening can extend 2 hours or more  after sunrise on 80 meters. Hundreds of contacts were logged during those openings. The path is less valuable in contests like CQ WW since Europeans are more inclined to move to the high bands in the morning since they are not only looking to North America for contacts.

With the high solar flux and still good low band conditions, quite a few station were worked on 6 bands. This was rare during the solar minimum other than the occasional Caribbean station.

W/VE callers

Many casual operators participate in major contests. Sometimes their willingness to hand out points isn't helpful. For W/VE stations in the ARRL DX contests, contacts with W/VE stations are worth zero points. Yet they keep calling. W call W, W call VE and VE call VE. No one wants to be rude but it becomes annoying when I have multiple DX callers that are covered up by one or two strong zero-pointers.

Sometimes I politely tell them "sri dx dx only pse". Half the time they keep calling regardless. Other times I work them to clear the frequency but don't log them. I know that other contesters do the same, while some are more rude and others shrug while working and logging them.

Many casual operators don't read the rules, know the exchange and have little understanding of each contest's unique rules and procedures. I am happy they are always there when I need them, so I keep it polite. It is more difficult to explain the situation on CW than on SSB.

Live and let live

Do you believe that everything goes in a contest? I don't but many do. When I operate in contests I avoid narrow channels of activity devoted to non-contest operating. Examples include FT8, beacons and a few SSB frequencies used to monitor for emergencies. I avoid running or calling stations on those frequencies. A few times I've violated the rule to work a juicy multiplier so I am not blameless.

Too many jump on those frequencies and run and ignore requests (or demands) to QSY. Those with a big enough signal may get away with the transgression. Their reputations is another matter.

Future

I have never been enthusiastic about operating a weekend-long contest by myself. It was true when I was a teenager in the 1970s and it's true now. I need to get my station into a state where I can invite others to join in a multi-op team now that the pandemic is abating.

My objective is to have fun and share in the energy that a team operation generates. It is an experience I have only rarely enjoyed since returning to the hobby and contests not many years ago. At first it was nice to do what I wanted when I wanted, which is sensible with a small station and QRP. But with a bigger station the demands of a contest weekend are far greater.

There is much work yet to be done, work that I've deferred during the pandemic. Major tasks include the shack desk, equipment and automation. Getting the antennas and rotators in good shape is important but is of lesser priority. This is the year to get it done.

Final note

It feels surreal to be discussing a topic as mundane as a radio contest in light of current world events. Had the contest taken place a few days later everything would have been different. In a way it both surprises and doesn't surprise me that few hams talk about the war on the air or in personal conversations. Life goes on. My family has history in that part of the world and I know many hams with close ties to the region. Conversations on bulletin boards are lagging and so are the page views on my blog while all of us are preoccupied by world events. 

73 to all.

Tuesday, February 22, 2022

Farmers and Hunter-Gatherers

Let's roll the calendar back several thousand years, before humans developed civilizations and cities. The major preoccupation was survival. That required growing or finding food. Tribes that learned how to farm continued to hunt game and gather plants and fruits necessary for a healthy diet. Whether a child grew to become a farmer, hunter or gatherer was determined by ability, family and culture.

Mechanized farming in our highly developed civilization is done by a small fraction of the population. Today's farmers produce what our ancient ancestors farmed, hunted and gathered, and do it so well that the rest of us can barely comprehend how our ancient forebears lived. A better understanding can help increase our contest scores -- really! So let's push the analogy.

If you know anything of contests you will have made the connection by now. Farmers run and hunter-gatherers S & P (search and pounce). Little pistols can only do well as primarily hunter-gatherers, and will farm (run) when they can. Big guns are farmers, but will occasionally forage (or concurrently using SO2R) for multipliers. Those with stations between the extremes, or in assisted classes (including multi-ops), more equally balance their tactics.

Farming, hunting and gathering are hard work, just as they were in the distant past. A farmer is forever worrying about the weather (propagation), terrain (geography) and predators (frequency "theft"). Seed must be kept, stored and planted, the fields irrigated, weeds picked, predators dissuaded and the crop efficiently planted, harvested and processed. 

Runners must find and protect their frequency on prime spectrum (fertile land), have a signal and tactics that withstand or overcome external forces, attract hunter-gatherers, and periodically abandon the farm to hunt and gather multipliers. Since game will cross the farm from time to time or be attracted to the crop there is opportunistic hunting as recompense for staying put.

Hunter-gatherers are always on the move. You must move or you die since food sources are scattered, those with legs move around, and once you deplete an area you must find another. The old and infirm who cannot follow the tribe fare poorly. So, too, the S & P operator must keep moving. You may not die when you stop moving but your score will plateau. A seer among the tribe (DX cluster or skimmer) may tell you what and where but you must go forth to seek and take what you need.

Early farming societies were often prone to poor nutrition due to the reduced food variety. Early civilizations dependent on agriculture were vulnerable to more mobile invaders because they had to defend their land and crops. For example, the Mongols needed to keep moving as their herds (temporarily) exhausted what the fields could provide. No matter the strategy, survival was difficult and risky.

Contest operators who exclusively run or S & P will plateau and fail to achieve the top of the contest rankings. I know contest enthusiasts who are uncomfortable running because it is difficult for them to deal with multiple callers or their signals are too small to hold a run frequency for long. Others love to sit on a frequency all weekend and let the hordes, including multipliers, come to them. They enjoy being sought and the attention a big signal attracts and may dislike the work of spinning the dial and hunting.

Runners (farmers) rarely work other runners since neither moves around much. The S & P operator (hunter-gatherer) will never work other S & P operators since they can only call runners. Specialization reduces score potential. Expanding skills and pushing ourselves out of our comfort zone requires effort and, at least at first, may not be enjoyable. Many mistakes will be made before significant improvement is achieved. SO2R multiplies the discomfort and effort.

An alternative is to join a multi-op team. Those who prefer running get to run and those who prefer S & P get to hunt and gather QSOs and multipliers. Both are needed. Early in my contesting career I preferred S & P. Operating from VE3PCA in the early 1980s I liked to man the station overnight when the pickings were slim and scouring the bands to eke out whatever I could -- we were approaching the solar minimum and spotting nets didn't exist. When the high bands opened at sunrise, I ceded the station to the runners and get a few hours of sleep. Our small group included both farmers and hunter-gatherers.

I expect that most readers have by now decided that I've pushed the analogy too far! I'll switch gears and close the article with a related topic that is too small for an article of its own.

Chasing DX and hunting multipliers in a contest require similar tactics. It is a challenge to be heard in the pile ups so that you can quickly log the entity or multiplier and move on to the next. Consider the following quote from the 3830 comment by V47UM in this weekend's ARRL DX CW contest:

"successful callers were mostly about 50-100Hz up or down"

CW signals that are near zero beat with each other are difficult to distinguish. Although calling high or low can be an effective tactic, it can backfire. When too many call high or low they will zero beat each other and the tactic can fail. The reason is that you can't offset too much or you'll be outside the other station's receive filter. However, keep in mind that what you really want is to call where others are not. When the majority call high or low, calling on frequency makes you distinctive. Listen to what others are doing, find the hole, wherever it is, and call there.

Since my transition from QRP with small antennas to my present big signal, tactical calling has less value. I usually do better by zero beating or calling on the frequency of the last successful caller. Big guns have the advantage of brute force. 

In the coming days I will describe my experience in the ARRL DX CW contest. There were high and low moments, and there were lessons learned. A few are worth sharing.

Monday, February 14, 2022

Hy-Gain Rotator Mast Slippage

As the temperature crept above freezing this week I made my first tower climb of 2022. It was to re-align the antennas (yagis for 6 and 40 meters) on the 21 meter high Trylon. The rotator is a Hy-Gain T2X (Tailtwister). This is periodic maintenance that is needed due to mast slippage in the rotator mast clamp. It happens approximately once per year. It has already happened once on the TH6 side mount and Ham-M rotator with the nearly identical mast clamp.

My story is familiar to owners of Hy-Gain rotators turning medium and large antenna arrays. The mast clamp has never been improved over the decades of production by Hy-Gain (now MFJ). After all, why would they incur the cost of risk of a major product change when there is no impact on their business? Hams keep buying them despite the flaws.

The number of rotators on the market is small and at least Hy-Gain is a known quantity despite the products' flaws. There are few cost-effective alternatives. I use them but I never buy them new. They are only worth the far lower price they command on the used market.

Here's a question about these rotators that is worth pondering: When the mast slips in the clamp, is it a sign that the clamp is deficient, improperly adjusted or that the the load exceeds the capacity of the rotator?

If you have a quick answer to the question, I suggest that you think again. Let's consider the capacity specification for the T2X for the common case where the rotator is largely isolated from bending stress by one or two thrust bearings. From the Hy-Gain documentation, as extracted above:

  • Braking strength: 750 ft-lb (9000 in-lb)
  • Antenna wind area: 20 ft²
  • Maximum effective moment: 3400 ft-lb

It is interesting that the several manuals of Hy-Gain rotators I perused for this article do not mention braking strength or vertical dead load. It is shown on the MFJ product page. The vertical load capacity is sometimes quoted as ~700 lb, but I can't confirm that value.

The precise values are somewhat tangential to the main thrust of this article. However, note that the braking strength is less than 25% of the MEM. Is the brake deficient or are the specs less than enlightening? It's the latter, and I have more to say about it further below.

Many hams worry more about the dead load weight than the braking torque limit. So much so that, in my experience, they insist that the thrust bearing take the weight of the mast and antennas to protect the rotator beneath! This is despite the facts that the rotator is designed to support the vertical load and the widely used thrust bearings are incapable of supporting any vertical load. The most common explanation I've heard is that the rotator is expensive and must be "protected". It is a peculiar belief with no basis in fact.

This may seem to be an irrelevant observation in the context of the present article. It is relevant since most hams are not as mechanically adept as they believe and the same lack of understanding appears in discussions about mast slippage.

For example, assuming the 9000 in-lb braking strength is valid, it can be reached by applying 75 lb of force to a 10' long lever attached to the mast, such as the antenna boom of a yagi. Failure would be catastrophic should the bell housing fracture. In practice it is more common for the ridges in the lower bell housing to wear or for the solenoid to bend or break, both of which will allow the mast to spin freely. The reduction gear train of a Hy-Gain rotator has little braking resistance on its own.

For the sake of discussion, let's assume that we install an absurdly large antenna on the mast. One so large that we are certain the braking strength will be exceeded in a moderate wind. If the mast clamp is perfect (no slippage possible) the brake or bell housing will fail. That would be an expensive failure. There is the immediate risk to the tower, antenna and property below, and the cost of a new rotator. You never want this to occur.

When the mast clamp is imperfect the mast will slip and the rotator will not suffer a catastrophic failure. The torque at which slippage occurs is far too difficult and imprecise to calculate. We can only hope that slippage occurs well below the threshold for catastrophic failure. Absent clamp or bell housing failure it is also important that the mast slip before there is sufficient force to damage the bell housing "teeth" and brake solenoid. Under the stress of continuous assaults of a too large antenna array the brake will eventually fail.

What I've described is a mechanical fuse. The slippage, although annoying, reduces the risk of catastrophic failure. Unfortunately that slippage often occurs with torque that is well below the braking strength of the rotator. Hy-Gain recommends pinning the mast to the rotator clamp (part 136, above). They helpfully mark a blank for the hole on the bell housing and provide a hole on the clamp plate. Following that advice can be a costly mistake.

With a pin through the mast and clamp there is no give. When a sufficiently large force occurs, and it will occur, something will break. In a typical installation the weakest link in the chain is the bell housing. The mast, pin, u-bolts and the exterior mast clamp plate are stronger. You can choose a bolt grade of lower tensile strength for the pin, however there is no good way to calibrate it to break at just the right amount of mast torque to protect the rotator. It will almost certainly break at too low a torque or not break when it should. A weak bolt will fatigue and fracture over time and it will then break at a low torque.

There is also a maintenance issue with pins. To insert or remove the pin the holes in the mast and clamp halves must be perfectly aligned. That can prove very difficult unless the holes for the pin are punched with the mast fully seated in the rotator clamp and when the wind is calm. Otherwise the weight of the mast and antennas must be precisely manipulated to align the holes to remove or insert the pin. One instance of removing and re-installing the rotator can make you regret using a pin.

There are less extreme methods to increase resistance to slippage. A few common ones are:

  • Increase contact area between the clamp and the mast
  • Teeth or grit to penetrate the surfaces of the mast and clamp
  • Set screw

Like many universal clamping systems the surfaces have a V shape. A range of mast diameters can be accommodated at the price of a low contact surface area. The ridges on the bell housing side of the clamp reduce the contact area and provide no sharp striations to penetrate the mast. The other surface is smooth. Even that might be enough if the clamping material was steel. Unfortunately, the clamp plate relaxes over time no matter how much the nuts are tightened, and aluminum striations will not penetrate a steel mast.

Last year I inserted a thin galvanized mesh to see if it would be gritty enough to bite the aluminum and reduce slippage. It made no noticable improvement.

The clamp hole for the pin can be threaded for a large set screw to penetrate the mast at one point. I doubt that would work because the flex in the clamp would relax the hold of the set screw as it already does for the u-bolts. I've seen it done but I have never bothered.

One thing you should not do is over-tighten the nuts on the u-bolts. The clamp will relax regardless and you risk breaking or galling the stainless bolts or, worse, cracking the bell housing.

It is possible to machine a one or two piece mast shim with an inner surface that conforms to the mast and an outer surface that conforms to the V shaped clamp surfaces. The increased surface area will increase the mast torque required for the mast to slip. I've never seen one but I have heard of it being done. I doubt that it worth the effort.

I earlier put aside the "maximum antenna size" specs and it's time to delve deeper. How did Hy-Gain arrive at the maximum square footage and MEM limit and what do they mean? This is less than obvious. For example, 20 ft² of antenna surface area tells us little without a great deal of context. Let's provide some.

For the 135 kph (85 mph) wind zone which is most common, at that wind velocity the lateral force on a cylindrical 1 ft² of projected area the static load is 20 lb. For the listed 20 ft² the lateral force is 400 lb. That's a lot, however none of it is seen by the rotator when the mast, tower and thrust bearing(s) are doing their job. The rotator will only be sensitive to torque. 

Torque is roughly in linear proportion to both antenna surface area and MEM. That tells us little since yagis are balanced by weight (CoG is at the boom-to-mast clamp), and by the cross-wind principle the torque should be zero. It isn't zero because the boom and elements are not in a laminar wind stream. At high wind velocities the air flow and mechanical oscillations are non-linear, 3-dimensional and can create brief periods of high torque. The 6° of motion the T2X brake allows adds to the peak strength of oscillations and mast torque. It is the peak torque that the rotator and mast clamp need to resist.

The MEM spec is no more than an heuristic tool to guess at what the rotator can deal with. As mentioned earlier, that the MEM is so much greater than the T2X braking strength makes it clear that the weight of the antenna is never applied to a lever equal to the length of the turning radius. The spec is little more than a rough guide, and that guide is of little value without more precise conditions where it applies. The lack of those conditions in the specs is telling: don't trust MEM!

There is no simple or straight-forward calculation, and two balanced yagis with the same surface area and turning radius will give different answers. Tube diameters, alloy and wall thickness, along with taper schedule, truss and element placement are all factors that make for the difference. So how do we interpret and what are we to do with Hy-Gain's specs?

MEM is defined by Hy-Gain as the product of antenna weight (lb) and turning radius (ft). This is a rough analogue for the expected torque under undocumented conditions. For example, a Hy-Gain TH7 has a cylindrical surface area (elements broadside) of 12 ft², weight of 75 lb and a 19' to 20' turning radius. 

MEM of the TH7 is 75 × 20 = 1500 ft-lb. This is less than half of the specified braking strength of the T2X rotator. Is this reliable? Can the T2X handle an antenna of the same size but twice the surface area (40 ft²)?

Certainly my recently installed 3-element 40 meter yagi is too much for a T2X with its MEM of ~8000 ft-lb. The wind load is 27 ft² but the weight is 4× that of the TH7. Doubling antenna size typically requires 2² the weight to be structurally sound.

My T2X survived moderately high winds with a TH7 and 6 meter yagi on the mast (total MEM of 1700 lb-ft), but that is hardly definitive. It's like proclaiming that I plan to live forever -- so far, so good! Tomorrow the T2X could shatter in a wind storm. There will always be a storm that will destroy any installation. It's a matter of probability: is that storm likely to occur once a year or once a century? We can only estimate, build and hope that century storm doesn't happen during the life of the installation. Building for a century storm may be unjustifiably costly for the ham budget.

With this in mind, is pinning the mast all that bad? We eliminate slippage and assuming our antennas are within the rotator's specs the rotator will survive. There is also the matter of the tower. Even if the rotator can survive the torque with a pinned mast the tower must also survive the torque. I have personally witnessed a tower twist and break in a strong wind, and the Ham II rotator survived. In that case both the tower and rotator were overloaded, and the mast was not pinned.

If we don't pin the mast, the rotator and tower can survive many severe wind storms. But we must climb the tower after those storms to realign the antennas. It would be nice to avoid this maintenance chore since I have so many others with my large antenna farm. I have already been up once to realign the side mounted TH6 after a wind storm. That is likely to be a regular chore since the antenna is not centred on the mast.

In the face of the several uncertainties I choose not to pin the mast. I prefer the maintenance over the relatively low risk of rotator or tower failure. I'll continue to grumble about mast slippage despite my choice. For those who must hire a tower rigger to do the job the balance may shift in the other direction. 

Alternatively, buy a rotator that is less prone to slippage and that has no brake mechanism. For example, one with a worm gear drive and a better mast clamp (e.g. AlfaSpid). Of course there are the matters of cost and the trading of one set of issues for another since every product has shortcomings.

There is no universal answer. But that is no reason to shrug and be complacent. Make a sensible choice based on calculations and facts. If you live in a hurricane zone or you have doubts about your tower, your choice should take that those facts into account. Rotator and tower failures are costly, and there is the risk of high liability for those living in a densely populated urban or suburban area.

Wednesday, February 9, 2022

Life in the Slow Lane: FT8

[Note: I've been busy so I have no well-developed technical articles in the pipeline. Instead I am going to start February slow. Real slow.]
Slowness is a notable characteristic of FT8 communications. That is an objective fact, no matter your opinion of digital modes and your operating habits -- casual, technical or competitive. The fastest QSO takes 1 minute and 2 minutes or more is not uncommon with QRM and QSB in the mix. That a long time to exchange call signs and signal reports! Although FT4 is twice as fast it is used far less. The few decibels of relative merit doesn't appear to be the reason.

I may be an outlier of my generation since I still like to drive fast, send and copy CW fast, eat fast, maximize my QSO rate during contests and not dwell too long on any one thing. I don't like speed because I'm a contester but it may be that I remain a contester because it's fast and exciting. Slow contests often bore me. Watching FT8 activity during a digital or VHF contest is as exciting to me as watching paint dry.

Occasionally I ask my non-contesting friends if they find FT8 too slow. From their surprised reactions the question appears to be unexpected. It's as if they're thinking: faster than what? Or: what's the rush? Those underlying questions seem to be ever present even as their answers touch on other issues, including the small stations that make digital modes so attractive to them.

I should not have been surprised. I am in the minority in my age group with my "need for speed". People my age tend to drive within the speed limit and prefer to savour their QSOs. Speed is more alluring to the young.

Most hams are growing old and are inclined to slow down the pace of their lives. They aren't contesters and they are not interested in rate. FT8's 15 second regimented periods are no impediment for the casual operator. It is not too slow to irritate and not so fast that it requires rapid reactions. The "Call 1st" feature provides additional relaxation by eliminating the need to make a decision about which caller to answer. Digital modes welcome and may encourage passive behaviour.

I use FT8. It is my go-to mode for DXing on 6 meters. I like what it can accomplish and so I tolerate its slowness. Attempting to spur activity on 50.318 MHz FT4 by calling lots of CQs has been unproductive. Few are listening.

I also use FT8 on 160 meters when the DX is lacking on CW, which is almost always true outside of contest weekends and the rare DXpedition. Mostly I just monitor to see what DX paths are open. I do not use FT8 on HF because there is plenty of DX on SSB and CW. At least, so far.

Digital is not my preference even though I love the technology for its ability to scrape a QSO from the merest wisp of a signal. FT8 is a mode you like or don't like, use or don't us. It's a personal choice. An increasing number of hams choose it and accept its fixed and pondering pace. That is not a problem for them. I am happy to use it to monitor 6 meters for transitory openings that are so difficult to exploit with the traditional modes.

My preference for CW and SSB is typical for hams of my generation. Younger hams feel differently. Many have never learned CW and have no intention of doing so. For many of them, their entry into ham radio was technology. For me and my peers it was communications. In the 1970s, ham radio was just about the only way for an ordinary person to reach out and talk to someone across the globe. Modern communication services have made our passion for HF and DXing look quaint to most people. 

Why does the speed of the mode matter? I'm a contester, but that's not why it matters to me. Indeed, when QRP was all I had I was not frustrated by the slowness of getting through to another station. I used it as an opportunity to hone my operating skills. I know many hams who use amplifiers so that they can rapidly log the QSO and move on. QRP is an undesirable handicap in their pursuit of speed.

Enticing more hams into contesting or FT4 is a losing cause. They like their slow CW and casual phone QSOs, and they're perfectly fine with the speed of FT8. It makes perfect sense to me when seen from their perspective.