Friday, August 25, 2017

Raising the LR20 150' Tower (Part 1)

Raising a 150' guyed tower is a major endeavour. There really is no comparison to self-supporting towers half that height. It is far more than 2x the work! For the vast majority of hams big towers are nice to look at but you wouldn't want to own one. After all, not only is there the expense, difficulty and danger of raising it you must also maintain the tower and all the antennas and associated equipment that it supports.

For myself I judge the effort worthwhile. Even so it is daunting. I've helped others put up and work on big towers, but that is no real comparison to owning one. The ground work is hard enough, and it only gets worse once you get up high.

This article is a progress report. I'll describe much of what I had to go through just to reach this stage in the project. Things are moving along well enough despite the many questions that needed answering and the obstacles I had to overcome. Part 2 will cover the rest of the project to completion.

Lifting the base section

A guyed tower with a pier base presents a challenge. At the beginning there are no guys. Yes, the base section with its bearing plate will stand on its own when placed on a level surface and will have some lateral stability when sitting on its pin, which is still not enough to raise sections onto it. There are basically two ways to go about it:
  • Assemble on the ground enough tower sections to reach the first guy station, lift it and place it on the pin with a crane or lift truck, then attach the first set of guys.
  • Manually lift the base section onto the pier, temporarily guy it, then lift sections until the first set of guys can be attached.
I chose the second method. It is certainly cheaper and it provided an opportunity to test my newly designed and constructed gin pole comfortably close to the ground. Two strong men could place the base section by muscle alone but in my case it would mean calling in a favour to convince someone to drive out to my isolated location for 10 minutes work.

I took the adjacent picture when the job was mostly done. You can see the basic elements involved.

A standard section with my newly constructed gin pole attached was braced against the pillar. Guy ropes stabilize it. My trusty old hand 2 ton winch (come-a-long) provides the muscle to lift the base section (~150 lb). The two sections leaned towards each other when the base section left the ground. Rope stretches. It was all very stable despite the leaning.

Lowering the base onto the pin took some sweat since I machined a very close tolerance for the 1" pier pin into the base plate hole. This is not at all necessary. I simply chose to stop when the existing hole was barely sufficiently enlarged since reaming a 1" hole in ⅝" steel plate with hand tools and a tiny drill-mounted grinder is not at all enjoyable.

Eventually I got the base section sitting on the pillar. I removed the gin pole and the section on which it was mounted. I noted several gin pole deficiencies which I proceed to correct.

Temporary guys

The pin alone is sufficient to hold the base section in place until temporary guys are attached. Just don't try to climb it!

The top of the base section was guyed with scraps of old steel cable I had lying around. Rope is not good enough since it stretches too much to be safe for lifting 3 sections onto the base section. The greater length of each temporary guy is ¼" EHS taken from an old tower. To this was attached ¼" aircraft cable to loop through the holes guy yokes holes at the top of the base section. At the anchor end I spliced on 3/16" aircraft cable to reach the turnbuckle and anchor plate. An abundance of clips and pre-forms holds it all together.

The temporary guys were tensioned to between 400 and 500 lb. More would have stressed the cable clips and the smallest cables more than I felt was wise. This tension worked well to keep the tower vertical and stable for lifting sections. Shaking the tower at the 40' level did induce some movement in the guys, which was expected and is not a safety concern.

Notice the ladder. This became a regular fixture at the tower base since only on the higher rungs is there a sufficiently large opening for a boot (or two) to fit.

Making the base section vertical

This presented more of a challenge than I expected. A level doesn't work well since the legs aren't vertical and the horizontal members are not reliably horizontal. I used the common trick of placing a spacer at the bottom end of the level so that when place either on a leg face or vertex the level is vertical. The turnbuckles are adjusted (or clips moved) until all legs are at the same vertical angle.

That took some fussing but was eventually done. Getting this right is very helpful to safely raise the section and then have the tower in good position to confidently set up the first set of permanent guys.

At this point a potentially serious problem appeared. The bearing plate was neither horizontal nor flat. I checked and rechecked yet the error remained. I learned from the previous owner that the flaw was always there. He had a custom bearing plate made and welded to the base section and it was not properly done. He never experienced any problem despite the flaw.

That may also explain why the bearing plate isn't flat. Consider that for my tower I calculate the pressure on the bearing plate due to tower and payload static load and the guy tension load to total close to 10,000 lb (4,500 kg).

I next consulted by email with a ham having the requisite expertise (and who has several towers of the same type). He eased my mind on the scope of the problem but strongly recommended that I grout the base. I proceeded to do that. A bag of non-shrink grout designed for bearing plates is inexpensive, widely available and easy to use (it's a common building material). The job was straight forward since I have experience grouting landscaping stonework and doing concrete repairs.

Lifting the base for grouting proved no great difficulty. A large cold chisel was inserted into the gap and used as a pry bar aided by a pipe as a snipe. A conventional pry bar was tried but was not up to a lift of 500 lb, the sum of two sections and the downward force due to tension on the temporary guys. Scrap ¼" angle stock kept the bearing plate elevated for the grouting.

The pillar was thoroughly wetted, swept clean and the semi-liquid grout mix shoved underneath with paint stir sticks. When the space was pretty well filled I used the pry bar to remove the angle stock and let the full weight fall on the grout. Because of the tight fitting pin I had to use a wood block and a small sledge hammer to pound the bearing plate down into place. The pressure would have filled most of all on any voids in the grout.

The grout that squeezed out the sides was removed and the edge shaped to give it a professional look. When dry the grout provided a perfectly mated surface for the distorted bearing plate. Note that the grout bonds to the concrete but not the steel; the bearing plate can still tilt as it should. In fact we could tell when the tower wasn't perfectly vertical by a seam appearing between the grout and base plate.

Gin pole

Since I can't weld I prefer fabricating devices from common metal stock and parts that can be found in hardware stores. It can be challenging at times. Devising a gin pole for the LR20 was just such a challenge.

First I had to deal with 3 different styles of tower sections and small variations within the most common style of section. These were the base section, one section with curved members between legs and 13 sections with angle stock members. Despite the differences all sections meet the same splicing spec and fit together perfectly.

The girts on all but one section have holes on the top surface for attaching support plates and other fittings. The positions of the diagonals was the greatest worry since this made the position of the lower attachment point variable. The base section also has non-vertical faces to be dealt with.

In the picture at right the completed gin pole is at the 50' level, ready to lift the next section. Two stacked heavy duty construction L-brackets comprise the upper hook. On the upper surface (not visible) is a short bolt that slips into a bolt hole on top of the girt (matching holes on the other sides of the girt are visible). A retaining nut is optional.

For the lower attachment I took a short length of 2" schedule 40 pipe that slips over the 1.9" OD of the gin pole 1.5" pipe. A U-bolt and machined angle stock clamps the sleeve to a diagonal member. A short bolt at the center of the angle stock (not visible) increases the bearing surface by bracing against the inner surface of the diagonal. Two drilled and tapped holes in the sleeve lock the gin pole to the sleeve.

To move the gin pole up one section the sleeve locking bolts are loosened. From the top the gin pole is lifted until the upper attachment is above the tower. The pole is lowered into the sleeve below (I made two to make this process safer). The bolt in the upper attachment is fit into the girt hole. Finally the sleeve locking bolts are tightened. The sleeve on the lower section is then removed, to be used later on the subsequent section.

For the section without bolt holes on the upper surface of the girts the gin pole is rotated so that the long bolt that secures the L-brackets faces the tower. It fits into a bolt hole on the outer surface on the girt. The retaining bolt in this case is mandatory. The pulley must be moved to opposite side of the gin pole so that it is always facing the tower.

The gin pole was given a few improvements to correct shortcomings I discovered during use. It is lengthened 18" with a schedule 40 aluminum pipe, making it easier to lift 10' sections while not becoming too top-heavy for one person (me) to safely lift and position.

Since the lifted section can easily snag on the gin pole bottom and protruding bolts I constructed ramps (shields) so that it can slide over these obstacles. The sleeve locking bolts are placed out of the way by rotating the sleeve so that they face inward.

The shields successfully reduced the incidence of snags that inevitably occurred even with tag lines to pull the lifted section away from the tower and gin pole at critical moments during section lifts.

Lifting power

My original intention was to use my lawn tractor to lift the sections. Unfortunately, as I feared, this didn't go well. The tractor is too light and the tire tread too smooth to gain enough traction to pull a free weight of 120 lb. There are solutions to these difficulties but that could not be quickly implemented.

I resorted to the winch used to build the Trylon tower. It's a more tedious but proven method. I used junk box angle stock to construct pinch clamps to secure the winch to the base section and allow the handle to turn unencumbered just beyond the tower leg. The winch must be operated from a short ladder since I was unable to attach the winch lower where the base section is very narrow.

The tower reached 70' with the winch. At that point I'd had enough with the painfully slow lift speed and tired arm muscles. My ground crew became restless as well since the slowness was boring. How I chose to resolve the problem will be covered in Part 2.

Pulling guys

Sacrificial pre-form as a cable grip on first guy level. It is not
fully wound so that it's easy to remove. The guy is at full
tension so a new pre-form is wound on the turnbuckle.
The temporary guys are still attached for safety.
Weight of 5/16" guy cable, strain insulators and pre-forms is considerable. For the first guy station at 35' I attached the guys to the tower section on the ground and lifted them as a unit. The trade off is that wrapping the pre-forms on the ground is easier than in the air but the lift is more work on the manual winch due to the additional weight. The gin pole is however up to the task.

With more guy weight at the 70' and higher guy stations it is not practical to attach them on the ground. The guys were individually lifted and attached in the air.

After the section with the guy station is attached to the tower the guys must be drawn out to the anchors in preparation for attachment and tensioning. This is a muscular job that must be done in stages to avoid undue bending stress on the tower.

Before raising the guys I built them out to the lowest strain insulator. A single span runs from there to the anchor turnbuckle. Partially used and therefore lighter cable reels were carried into the field by wheelbarrow. The cable is attached to the strain insulator and unreeled back to the anchor. One person pulls moderately hard on the cable to get the rough distance and a second marks a point about 2 meters out from the turnbuckle. That's where I attached my cable grips for pulling the cable with the come-a-long.

I use "sacrificial" pre-forms as my cable grips. They are far cheaper than the proper tool and work perfectly well. I call them sacrificial since pre-forms are not designed for reuse. I selected old stock 5/16" pre-forms from my junk box, using 3 on the guys and 3 on the turnbuckles. Only when near to full pre-load tension was reached did I use a new pre-form to attach the guy to the turnbuckle.

Each guy was pulled part way with the come-a-long then tied off with a sacrificial pre-form. With just the one come-a-long it takes well over an hour to make the circuit of the anchors a few times until the tension was high enough and the tower adjusted to vertical that the permanent pre-forms could be attached. It wouldn't do to find that a final adjustment is beyond the range of the turnbuckles.

Professionals use 3 sets of grips, tensiometers and come-a-longs plus one or more transits to do the job quickly and easily. A few of the sacrificial pre-forms had to be discarded during the tower raising when they fell victim to overuse.

Poor man's transit

The tower must of course be made or kept straight and vertical as the guys are pulled to full pre-load tension. It is easy to have the tower lean or bend when there's 1,000 lb of tension on the guys. The professional tool to do this is a transit (theodolite). Unsurprisingly I don't own a transit and although I can rent one I also do not have the training to use one properly.

Instead I used what I call my "poor man's transit". Although totally ridiculous it does surprisingly well if you use it carefully. My crew at the time, Brian VE3CRG (on the left) and Geoff VE3KID, show how it's done. A new aluminum tube (surplus but never used 2.5" aluminum tube) is the straight edge that is tilted to vertical with levels 90° apart (or one if you trust your arms to steady the tube). Do this standing near a guy anchor. You then sight along the tube towards one leg of the tower. Deviation from vertical can be estimated from the width of a tower leg, as sighted at the guy station on the tower. Later I attached the tube to a fixture so that it didn't need to be held in place during use.

Brian VE3CRG (left) and Geoff VE3KID using the poor man's
transit. The "hazmat suits" supposedly protect them from the
multitude of ticks and biting insects in the wet hay field.
To correct deviations from vertical the opposite two guys are adjusted the same amount in opposite directions. That is, if you loosen one turnbuckle 3 full turns the other is tightened 3 full turns. Done this way the tower will move in the desired direction without changing the guy tension. You can calculate the number of turns per the turnbuckle thread pitch (keep in mind there are two screws, not one, so the rate of change is double the thread pitch) or guess and then correct your guess after rechecking with the transit.

You must repeat the process with the transit at the other two anchors. It doesn't have to take long if you go about it methodically and don't rush.

Let me interrupt here to warn you about shortcuts and to bust a common myth. Do not use a level on the tower itself to test for vertical. It doesn't work. Although the splice tabs at either end are usually exactly where they ought to be the tower members in between may not be. Welding, shipping, previous usage and abuse can add deviation and ripple that will fool a level. Move it from place to place on a seemingly straight section and you'll see. Small deviations can trick you.

Even if the tower steel is perfectly straight the level itself is often not adequately calibrated. Use each side in turn and if they do not agree the level is not calibrated. A perfectly calibrated level is still inadequate since the tower is many times longer than the level and an imperceptible deviation will be greatly amplified.

The myth is that a guyed tower or mast is vertical when the tension in the guys is equal. A tower can lean quite a bit out of vertical before any measurable amount of tension differences among the guys appears. This is because the guy tension is far greater than the horizontal force of a leaning tower. In fact if you tighten one guy you'll find the tension in all the guys increases the same amount.

Tension differences are often due to incorrect use of the tensiometer when attached to the cable. A persistent 100 lb difference in one guy was corrected by reducing the tension in the temporary guys. This discrepancy is in general a sign that guys at multiple levels are either not properly adjusted or there may be a flaw in a tower section or a section splice is misaligned.

Another source of error is the lay of the guy strand. With only 7 strands in EHS each is quite large gauge. Move the tensiometer a short distance along the guy and remeasure. A high or low point on the EHS where it contacts the tensiometer can affect the reading. That small amount of cable deflection difference on 5/16" EHS can be 50 to 200 lb in my experience.

Going higher

I'll end Part 1 at 70' where the second guy station is located. This is almost halfway. The tower is vertical (using my "improved" poor man's transit), the guys are tensioned and the temporary guys are gone. The next sections to go are parked alongside the base.

Although the Trylon tower is only a foot or so taller I am still looking up at it from the 70' level of the LR20. The Trylon sits on the higher grading surrounding the house. The hay field undulates, with high and low points, and a general downward slope toward the swamp behind the tree line. Terrain matters when it comes to height.

The top half of the tower has challenges unlike the lower half and will require changes in technique and equipment. For example I am retiring the winch since it is too slow and difficult for the longer lifts. I'll discuss this and more in Part 2.

I'll close with a picture I took at the edge of the hay field while taking a break from working on the first set of guys. It is always refreshing to occasionally take in the scenery. Putting up a big tower is a lot of work so frequent breaks are mandatory. Fatigue causes accidents. Stop when you no longer feel 100%.

"Bring me milkweed or I start a tornado to blow down your tower!"

Sunday, August 20, 2017

Solar Eclipse 1979

In early 1979 I was finishing my graduate degree at the University of Manitoba in Winnipeg and preparing for the move to Ottawa later in the summer. Just my luck that a total solar eclipse was about to make a visit. This was a rare opportunity since no travel was required; few have the pleasure of seeing this phenomenon in their lifetimes unless one travels to the path of totality. One came close in 1963 when I was very young and impressionable. Throughout my youth I looked forward with great anticipation to the real deal in 1979.

As is usual for February in VE4 the weather was virtually guaranteed to be cold and clear. That held true for the morning of February 26. Although I had the desire to drive north to get a longer view of totality, or even just stay home for the day in the north district of the city, I decided that an eclipse extension of 15 or 20 seconds wasn't worth it. As per routine I drove to the university campus in the south of the city where totality would be just shy of 2 minutes duration. I had an enormous workload to get through if I intended to graduate.

Thoughts of radio were far from my mind. Going back to my logs from that time of my life it was pretty clear that my on air activity was extremely limited. I didn't have the time. Although I had an interest in the eclipse's impact on propagation I was infinitely more interested in witnessing the event with my eyes, not through headphones.

Word got around by mid-morning that staff were getting access to a number of building roofs for improved eclipse viewing. Students were welcome. A few friends and I joined a small group on top of one of the science buildings. The view was great even though we were only up perhaps 6 stories. There were no taller buildings, prairie trees tend to be short (leafless in February) and the landscape was flat out to the horizon in every direction.

It was also painfully cold. Few of us were dressed for an extended stay in -20° C or worse temperatures. The breeze above the rooftops increased our discomfort. At intervals each of us would duck inside to warm up. Waiting for totality is not very interesting; there's only so much I could stand of staring at a slowly encroaching shadow over the sun through the viewing filters that were passed around.

As totality approached the temperature was already noticably dropping in the dimming sunlight, already quite weak from a winter sun low in the south-southeast sky. I tried to look for the rapidly moving shadow edge sweeping over the prairie from the west but failed to see anything very distinct. Then it was dark and all eyes turned toward the main event. For a moment I saw Baily's Beads.

The next thing I noticed was the expansive corona. This was the time of a solar maximum, and historically quite a fairly strong one. The corona expands under these conditions. At about the same time everyone noticed and pointed at a large arcing prominence on the upper left limb. It was quite spectacular. This linked photo shows a reddish glow but not the prominence. Possible the photo was taken later during totality when, as I recall, the encroaching moon blocked the prominence from view. Also visible was a smaller prominence and other evidence of high solar activity.

Stars were visible though not as many as I'd expected. The sky was as dark as twilight and grew darker then lighter again as totality progressed. Then it was over. After a couple of minutes the crowd began to disperse. The repeat viewing of the the partial eclipse in reverse couldn't keep an audience in that bitter weather.

Over the following weeks I heard reports of hams experiencing some interesting low band conditions with paths crossing and along the path of totality. Although the internet existed and I had even used it a few times it played no role in connecting hams or distributing news of operations during the eclipse.

I have never travelled to view a solar eclipse and I won't be for this one either. If I have the time I will turn on the rig and listen on the low bands. It's unlikely that I'll bother to transmit. I will only be a spectator. For those of you in the US lucky enough to experience totality on Monday be sure to get outside and away from the shack for at least the several minutes of the main event. It's very worthwhile.

Monday, August 14, 2017

Monitoring 6 Meters

Monitoring 6 meters for openings was very time consuming when I was very active during the 1980s. Aside from spinning dial there were the following options:
  • Monitor 28.885 MHz where 6 meter aficionados gathered. This was a good choice during sporadic E season since 10 meters would open before 6 meters. That is, when 10 meters had sporadic E propagation there was a reasonable chance that it would rise to 6 meters.
  • Monitor commercial VHF broadcasters and other services at known frequencies and locations either just below or above 6 meters. Of course your directional yagi would have to be rotated to each in turn. Some had non-directional vertical and horizontal antennas dedicated to monitoring.
  • Monitor 10 and 6 meter beacon frequencies. See previous point.
  • Use the scan feature on the rig to continuously cycle through the beacon and high-activity band segments, typically from 50.000 to 50.150 MHz. 
For VHF DXers there was the other problem of activity since back then most countries in the world did not have a 6 meter band. Among those that did there were many whose band did not overlap that in North America. This required monitoring other frequency ranges, mostly up above 52 MHz. Cross-band QSOs were often attempted with 10 or 4 meters, or at least a shout out on 28.885 MHz of "yes, I can copy you!"

Now that the 2017 summer sporadic E season is rapidly winding down, and being my first time being serious about 6 meters in many many years, I though it would prove interesting to review how I went about monitoring for activity. It is very different! In believe the change is for the better.

Still irritating after all these years

This lowest of VHF bands remains both intensely intriguing and challenging. Having a 6-element yagi up 24 meters doesn't change that. In a way it makes it worse since there are more marginal openings than with a less capable antenna.

Despite the numerous new techniques to monitor for activity it is still terribly irritating in many ways. Some of the old irritations are gone but have been replaced by new ones.


There are more beacons on the band than ever before. This is good although it often contributes little to the logbook. Many of the best beacons are in great locations that may not indicate that anyone in the beacon's vicinity are workable. That's okay since it is still useful as an early warning of possible QSOs.

Worse are the beacons in rare or out of the way locations where there is no one active. How frustrating to hear beacons and have the opening go to waste since there's no one to work.

More beacons means more beacons nearby. I quickly learned to recognize that many of the beacons I can hear weakly while scanning the band are coming in by tropospheric propagation from within a 500 km radius. My antenna is big enough and high enough to make them audible. Interesting but not useful to me since I am primarily interested in ionospheric paths, especially DX.


How nice to be able to sit back, pick up the smart phone and connect to a cluster to see what's happening on the VHF bands. From a perusal of the spots I can decide whether it's worth my time to head over to the shack.

While in the shack the stream of incoming spots keep me aware of what's going on at other stations in this part of North America and elsewhere. This is particularly true when the spots are from better equipped stations which again serve as an early warning of an opening that is workable. I can now better decide whether to leave the shack or stick around.

I also like to see spots for paths far away from me, especially among European stations. Intense sporadic E propagation over there can be an indicator that conditions for clouds to form here as the clock rolls around to the same local time. Similarly it tells me to watch for clouds over the Atlantic that can support propagation to Europe. The same is true for activity far to the south since all it takes is a E-layer cloud to form and link VE3 into paths to South and Central America.

FM broadcast band

Back in May I got annoyed one morning when a radio station I sometimes listen to developed distortion and would abruptly be interrupted by completed different program material. At first I assumed they were having technical difficulties. Then it dawned on me that is was sporadic E propagation from a US station that was interfering. The MUF had risen above 90 MHz.

This style of monitoring is nothing new. However it is new to me since I now live in what is a fringe reception area for FM broadcast. Back in Ottawa this would never happen no matter how good the propagation since the local transmitters always win the battle of FM capture effect. Living in a fringe reception area gives me a new monitoring tool.

Band monitor scope

It is no longer strictly necessary to have the receiver scan the band for openings. A pan adapter or simple wide band scope provides a snapshot of a large portion of the band at a single glance.

Although the monitor will miss the very weakest signals it is still a very useful tool when an opening appears imminent from other indicators or to keep an eye on the band when the opening is patchy, coming in at random intervals.


This was an interesting year for digital modes. When I got on the air in June most activity was SSB and CW along with a steady but not extreme amount of JT65 activity near 50.276 MHz. Then the FT8 beta arrived and within a couple of weeks not only did it supplant a large proportion of the JT65 activity it also displaced quite a lot of SSB and CW activity. The relative rapidity of QSOs compare to JT65 and the ability to exploit marginal opening that do not support traditional modes have made it wildly popular.

I did not operate digital modes this season. This was due to a combination of not great interest on my part and difficulty interfacing my FTdx5000 to my ancient Vista laptop. The laptop has become quite unreliable when interconnecting via the USB ports for reasons only a Microsoft engineer could understand. The laptop will be replaced but it is what I use for now.

What I did with digital this year is use it as a beacon. I would watch spots for 50.313 MHz to check for possible openings for CW and SSB, and keep the rig's second VFO tuned to that frequency to check for signals. I had only limited success with this monitoring technique. The problems were twofold. First, marginal openings often stayed marginal and therefore only usable with digital modes that can operate at negative SNR (signal to noise ratio). Second, FT8 became so popular that even with good propagation many hams stuck by 50.313 MHz rather than move to CW or SSB.

There were numerous times when beacons were loud and there was heavy FT8 activity that I would repeatedly call CQ on CW or SSB and get no response. Next year I'll have to decide whether to make the switch to digital. The technology fascinates me -- I have experience writing signal processing software -- but it leaves me a bit cold when it comes to operating. Having my computer talk to your computer doesn't excite me.

How I did this year

So with all that monitoring my results this sporadic E season ought to show it. Yes and no. Knowing the band is open or close to opening is no guarantee that the log will rapidly fill up. I missed some excellent openings in May and early June before the antenna went up. The day after the antenna went up I worked 10 new countries in the Caribbean and South America. So far so good.

Then my progress slowed drastically. This was not a great sporadic E season from around here where DX is concerned. Those operating JT65 and FT8 did far better. Good monitoring options help little when the openings are few in number or not bringing in signals strong enough for CW and SSB. As I write this I have 33 countries on 6 meters, up from 19. As with all my counts this does not include my activity earlier than 2013 when I chose to reset all counters after returning to the air after 20 years away. Counting those I would now have DXCC on 6.

I paid little attention to most single hop openings except during the CQ WW VHF contest in July. Those are common and no longer of great interest to me outside of contests. It also means less time spent running to the shack to work the same old stuff. I am not obliged to work every opening just because I'm a 6 meter aficionado. Whenever there was a hint of DX or cross-continent propagation I was there. That's what interests me.

Particularly disappointing was only working one mainland Europe station this year. I heard the CS5BALG beacon quite often but few stations. Perhaps the biggest surprise DX was TF3ML/P calling CQ on 50.110 MHz. I was looking east on CW when I saw a signal up band on the rig's monitor scope. He sounded as surprised to hear me as I was to hear him. At the time of our QSO there no spot for him; I changed that.

I discovered that to many stations my grid square -- FN24 -- is wanted for VUCC. There are other stations in this grid, both in VE3 and W2 so this surprised me. In the contest a few stations asked me to go to 2 meters, which I had to unfortunately decline. I may have 2 meters capability next year.

All in all a mediocre summer on 6 meters for me. I enjoyed it nonetheless. Modern monitoring options make operating more relaxing since I no longer have to sit in the shack or have a rig on in the background scanning the band. I am looking forward to next year, and even the winter sporadic E season.

Thursday, August 10, 2017

Battling the Calendar: Time to Set Priorities

It's August and warm. This is great weather for building towers and antennas. Unfortunately it won't last. My plans for 2017 are ambitious and I am increasing worried about running out of calendar room before contest season gets seriously underway this fall. Worse, winter comes in fast and hard around here. This calls for setting of priorities so that if I do run out of time I will have the best station possible before winter puts an end to antenna farm construction.

Before getting into the topic of this article -- setting priorities -- there is one important observation I would like to make: the interchangability of money and time. It is always possible to accelerate the plan with money. For example, I can hire a company to put up towers. I have quotes and experienced hands ready to go to work. Another example is antennas. I can buy commercial products rather than design and build my own.

For me the building of a competitive station is not only about achieving a result. The journey is itself an objective. Designing and building what I can is a tremendous learning experience and can be a lot of fun. I am willing to forgo or delay some projects so that I can do it myself (or with friends). At the other extreme I need only sit at my desk with a telephone, credit card and cheque book and soon enough I will have a complete and highly competitive station. That approach does not interest me.

Therefore I resort to picking and choosing where to apply my effort. Spending where necessary and applying my own time to projects I want to do myself. With that preamble I will now jump into the main topic: how I set priorities for the time remaining to me this year.


The tower is in fact perfectly vertical. It's the
photographer (me) that has developed a lean.
For DX and contests height cures many antenna ills. Even an inverted up high will usually outperform a low yagi or vertical. Therefore the 150' tower is my highest priority. If it's all I get done this year I can put up a few inverted vees and side mounted a couple of tri-banders, and in combination with the TH7 up 21 meters I can do very well in the fall and winter contests.

This is why there have been few antenna articles lately. The tower is consuming most of my available time. It is not that I haven't been modelling and planning antennas and gathering construction material, but that these are very much works in progress and dependent on the tower being built.

As you can see in the picture I am not quite there yet! However this is one of the most difficult 20' of tower I've ever done. Getting to this point took a lot of time, worry, effort and money.

As I write these words I am ready to put up the remaining 13 sections. I have the parts and the tools and all the problems I've encountered have been solved. I will write more about all of this in one or two future articles.

Minimum viable antennas

In the high tech industry we are always talking about minimum viable products. The same thinking can be applied to contest stations. My time and resources are limited so I have to think about the least amount of antennas that will make me effective and competitive this fall.

Assuming the big tower will be ready I have tentatively selected my minimum viable antennas:
  • Rotating at the top of the 150' tower will be the Cushcraft XM240 and, preferably, a long boom yagi for 20 meters. The XM240 will go at the top of the mast and the 20 meter yagi at the bottom. They'll be turned with a prop pitch motor. With just the one tall tower I had to decide between a large yagi for 20 or 40 meters. I decided to go with the easier project for this year. Design and construction plans are underway.
  • TH6 at 110' (35 meters) side mounted and fixed on Europe.
  • Explorer 14 at a to be determined height side mounted and fixed south.
  • Inverted vees or wire yagis for 40 and possible 80 meters on one long boom at ~80' to 85' (25+ meters). If built the wire yagis will be electrically reversible between Europe and the US/Pacific. Design work will be required to allow effective interlacing of elements.
  • Vertical for 80 and 160 meters, using one radial field as the core of a future 80 meter 3-element vertical yagi. I've already warned my neighbour that this will take 1 acre out of hay production due to the radials.
  • One or two small flag or pennant receive antennas to the west and south to complement the Beverage to Europe.
  • The Trylon will continue to support the TH7 at 21 meters. The 6 meter yagi will be left where it is atop the mast and will occupy that mast space in preference to any HF yagi. I may install a multi-band inverted vee on the Trylon to complement the low 80 meter inverted vee and cover short paths on the low bands.
High bands

My strategy for the high bands is to have good all around coverage on 20 meters with a decreased emphasis on 15 and 10 meters. For this part of the sunspot cycle I will take my chances with less height, less gain and fewer direction choices for the upper two bands. I may miss some multipliers but I will have decent coverage for the most productive paths: Europe, South America and US.

The long boom 20 meter yagi up high will catch marginal openings to Europe in the early morning and overnight and allow pursuit of long paths to Asia, South America and the Pacific.

On 10 meters I will only have the TH7 at 21 meters and perhaps the Explorer 14 up higher and pointed south. Even with a low solar flux the South American path will open and I want to to be ready. I expect nothing on 10 meters with the TH6 fixed on Europe.

I am most compromised on 15 meters with this minimal plan. The TH7 will adequately cover the US and Caribbean and other short paths. With the only other 15 meter antenna -- the TH6 -- fixed on Europe I will have to do all other 15 meters operation on the TH7. Hopefully I won't miss too many multipliers in South America, the Pacific and Africa. I don't expect much from Asia on 15 meters this winter.

My best performance will be on 20 meters, which along with 40 meters are the most productive contest bands at this point in the sunspot cycle. With a large yagi up high, the TH7 low and two tri-banders fixed on Europe and to the south I expect to do quite well.

Low bands

The XM240 rotatable at ~46 meters height should perform well on all DX paths. If I can get a wire yagi completed I can search out marginal openings with the XM240 while the wire yagi is dedicated to Europe and the US. While not ideal antennas I expect this combination to be effective. If the wire yagi doesn't get built in time an inverted vee at 35 meters would still be an asset.

On 80 meters an inverted vee at 35 meters can address most of my needs, although it is not going to be very competitive. That changes if I can expand it to a 2-element wire yagi, switchable between Europe and the US. The vertical, which I fully expect to get built, will complement the horizontally-polarized yagi or inverted vee.

The 80 meter yagi array, for which the vertical is the driven element, can be worked on over the winter by adding switching systems at each element. However the radial system will need to be put down before the snow arrive or the array will be deferred to 2018.

For 160 meters I would like to make the 80 meter vertical switchable between those two bands. This is per my design plans from some time ago. As a backup plan I will run a vertical wire up the big tower and lay down temporary vertical for the winter. This is not ideal since it can compromise SO2R operation with the other antennas on the big tower.

Receive antennas

The one Beverage pointing northeast is a good start but wholly inadequate. The lack is especially acute if my minimum viable antennas do not include directional antennas for 80 and 160 meters. Without directivity copy on weak signals (whether QRP or marginal paths) will suffer, and that means lower scores. As it is said: you can't work them if you can't hear them.

For reasons I may elucidate in a future article I am strongly leaning to a set of 4 bi-directional Beverages (8 directions) as my preferred receive antennas. Those take some time to design and build. Not only must almost 2,000 meters of overhead wires be run there are the transformers, terminations, grounds, switching system and feed lines.

That's a lot of work to fit in this fall. Unfortunately receive antennas must be placed lower on my priority list. Simple but efficient transmit antennas come first. Low band directional antennas, if any can be built by the fall, are higher priority than receive antenna since they give some receive advantage and also a transmit advantage.

Work on Beverages can proceed during the winter when work on towers and other antennas slows or stops completely.


Burying cable on my property is a problem. Although hay farming doesn't interfere with shallow burial there is a greater concern: trees. The previous owner did a wonderful job planting trees and plants everywhere, with flowers blooming in sequence throughout the spring and summer. There are apple trees and other kinds of fruit I haven't yet determined. Trees provide shade where shade is useful and visually complement the house, stone walls and field boundaries.

All very pretty but ever try to bury cables where there are tree roots? I don't recommend it. When we were excavating for tower anchors near the edge of the field I purposely sited them to be far enough away to avoid roots. I was wrong -- those roots extended horizontally farther than I'd thought possible.

Because of that and as a matter of expediency I will run the cables overhead, with grounding for lightning at select locations. How this will be done is not finalized. Many cables will, I expect, lie on the ground for the winter. Once haying is completed in early autumn there will be little traffic in the fields.

In the yard itself I will likely stay overground up to a central switching location. From there I may go underground for the final 10 or 20 meters to the house (and another ground). Again, this may all end up lying on the ground for the winter.

Station automation

Effective contesting requires integration of the rigs, logging software and antenna switching. The requirements are even greater when operating SO2R or multi-op. However I expect that what I'll have time to design and build this year will be mostly manual rather than automated.

As a minimum I will simply run multiple transmission lines from the switching box location into the shack and use manual coax switches to select antennas. While hardly modern and an operating inconvenience the automation can be done over the winter or next year. The QSOs I'll miss due to long duration antenna switching and verbal negotiation between operators are relatively few.

Alternatively I may purchase one or two remote coax switches that would be located outside at the switching location. I can always sell them later when a fully automated system is in place.

What I must do this year is buy a new computer for the shack that can handle the multitude of connections and have the CPU power and RAM to support all the features of N1MM Logger. My ancient laptop can only handle 3 windows open concurrently and even then will occasionally fail to keep up with operating demands.


QRO is in my plans. Whether I get to it this year I don't yet know. Buying an amplifier is easy enough, and wiring it for 240 VAC is not a problem, but there are other issues that power will only exacerbate. For example, the filtering requirements are more onerous with a kilowatt compared to 100 watts. Building receive and transmit filters takes time I likely won't have.

To operate SO2R or multi-op requires two amplifiers. That's another burden that may not fit into this year's schedule. My alternative would be to use low power on the multiplier or S & P band.

Back to work

Writing for this blog takes time that could be put to building the station. The same could be said of every other activity in which I partake, including seeing family and friends. I am not so fervently dedicated to station building that I will exclude everything else from my life. Sometimes I even like to relax and read or do nothing at all.

With the garage and workshop built I now find that evenings can be put to use. With the doors closed and windows open the hordes of biting insects can't get in. It's almost cozy in there. Of course it'll get cold in the winter but for now it extends available work time into the evenings and darkness. For example, this evening I spent an hour in the garage fitting thimbles to turnbuckles. It's a job easily done indoors and therefore perfect for doing in the evening.

Of course I already have a tower and there is maintenance to be done by the fall. All the cabling on the Trylon will need to be redone and the antennas adjusted.

Lots of work remains to be done on the station this year. All I can do is prioritize, keep at it and hope for the best. Luckily I have a few friends who will help on the big job. Doing the work with others can make it more enjoyable and sooner strike the high priority items from my list.

Sunday, August 6, 2017

Wrestling With Steel Guys

In an earlier post I mentioned that I am guying my big tower with steel. Although non-conductive guys eliminate interactions that can compromise antenna patterns they are more expensive. In my modelling of potential interactions I found that for my intended selection and placement of antennas there is a pattern of non-resonant lengths that is perfectly acceptable. Interactions among the antennas will likely be the greater concern.

Having selected steel I was faced with the perils and other difficulties in working with steel guys.

On the left you see a large reel of LDF4-50A Heliax. On the right is a much smaller reel of 5/16" 1x7 Grade 180 EHS guy strand. Their weights are similar (heavy!) and contain approximately the same length of cable. Both appear entirely innocent. Appearances are deceiving.

The Heliax is light and somewhat fragile. It is easy to handle provided you properly unreel it to avoid kinking.. The reel of guy strand is not light and it is not fragile. Indeed it is a serious hazard to your health, fortitude and sanity when not handled with extreme caution. That's no exaggeration.

The first thing to realize is that the guy strand is not comfortably coiled on that reel. Those coils hide an extraordinary amount of stored elastic energy. When released from the restraining staples the cable releases that stored energy as it rebounds to its resting state: straight.

My procedure for freeing the cable for use is to lightly hammer a pointed tool, such as an awl, between each staple and the cable to create space for the cable to move. It will stay coiled if you are careful not to go so far that the staple is ripped out of the wood reel by the cable.

With the staples loosened the cable is pulled back out of the first two staples. This isn't easy since the cable is pushing hard against the outside surface of the staples. It violently snaps to attention when exiting each staple. Take that as a warning!

Move off to one side of the reel when pushing the cable through the final staple. A long steel rod tapped with a hammer against the end of the cable is a good way of doing this. However you do it you should not have any part of your body between the sides of the reel. Alternatively use very strong vice grips on the cable and position the reel so that it can recoil. It can work but I don't like the risk since the reel recoil takes too long due to its weight, then if the pliers aren't quite tight enough the cable will whip back and around the reel at high speed.

When the cable emerges from the final staple the cable will kick backward as it unwinds and straightens. If you're in the way you will be hurt, perhaps badly. Stay out of the way.

Unreeling the guy cable for use can be done in several ways, provided you provide a barrier or other restraint so that the reel or cable doesn't get away from you and make a big mess. The risk of the cable whipping out and striking you remains right up until the reel is emptied.

Cutting and joining non-resonant lengths

EHS is not difficult to cut with the correct tool. For 5/16" guy strand I use ⅜" bolt cutters. The jaws are large and hard enough and the arms have enough mechanical advantage to enable anyone with average strength to cut 5/16" EHS.

If you don't have sufficient strength brace one arm of the tool against the ground and carefully push down on the other with two hands using your body weight. Open the jaws wide so you can push the EHS in deep for the greatest mechanical advantage.

Do this carefully! When the cable severs the two ends will spring away from the cutter if not restrained in some way. Make sure you're wearing skin and eye protection and do not place your body where the ends are likely to jump. Alternatively use clamps or heavy weights to restrain the cable. Standing on both sides of the cut with heavy duty work boots can work well if you can operate the cutters with your arms alone.

Watch out for the cut ends: they are hard and sharp. If the strand partially unravels during the cut -- a common occurrence -- wind them up again so they sit flat. Wear gloves since it's easy to pinch your skin doing this.

To minimize waste it is best to cut the longest non-resonant lengths first (43' in my case). This way when you reach the end of the reel you can cut the remnant into the needed short lengths. You'll also want to keep long lengths on hand for the variable length from the anchors to the linked set of non-resonant lengths.

The non-resonant lengths are joined with insulators and pre-forms. At each joint you need one insulator and two pre-forms. Since the portion of the pre-form from the insulator to the EHS is part of the segment length you should cut the EHS segments at least 6" less than the required length. A few inches either way is not critical so don't fuss over the measurement.

I won't give a lesson on attaching pre-forms since I am not an expert. What I will tell you is that it takes some muscle, hand protection and a clean surface. Don't do it on grass or dirt! The only grit you want between the grip and cable is that with which the grip is coated. Foreign material will reduce the strength of the joint. I did most of the work in the garage then moved to the gravel driveway when the length required more space.

The larger the insulator the farther out the wrap begins. The pre-forms have helpful paint markings. The inner one should only be used for thimble terminations. The outer one is for insulators, but you can sometimes start the wrap sooner depending on the insulator. I did that for 502 size insulators while the 504 lined up pretty well with the outer paint mark. Don't force the wrap since you could add unwanted stress to the pre-form and insulator.

Eventually the guys will start coming together. It takes time and should not be rushed. Take a break if you get tired. Fatigue causes mistakes and injury. The most common risk in my experience is pinching fingers while wrapping the pre-form around the EHS. Most dangerous are the start and end of the wrap. Holding the thimble or insulator down with a work boot or gripped in a work bench helps to hold everything in place when you begin the wrap.

Coil the guys and put them out of reach

The relaxed coil diameter for the 5/16" EHS I am using is about 5' to 6'. Don't force it into smaller diameter coils for storage and carrying since you'll need restraints to prevent accidents. You'll also discover that the completed guys are heavy. A 500' reel of 5/16" EHS weighs approximately 120 lb so you can see that even a short 6' length is not an inconsiderable weight. Insulators and pre-forms add even more weight. When fully assembled a guy for my tower can weigh up to 100 lb.

If you need to temporarily store the completed guys put them where people and pets won't tangle with them. Curious children can quite easily hurt themselves. Not only are the ends sharp they will easily tangle feet when you try to step over and around them when they're lying on the ground.

Attaching guys to the tower and anchors

Thimbles are used to terminate guys at the tower and the anchor. They allow the pre-forms to maintain their shape and therefore their strength. Since pre-forms are wider than the guy strand for which they're made the proper thimbles are typically one size larger. For example, for my 5/16" guy strand the thimbles should be at least ⅜".

Don't go larger unless you must since larger sizes are more difficult to use (more force required to spread and close) and may be a tight fit in turnbuckle eyes and some brands of guy station. Thimbles made for pre-forms are thicker, deeper and larger radius than those for more flexible aircraft cable. They should also be hot-dip galvanized to last a long time outdoors.

Since as I write this I don't have thimbles in hand the above picture is of a used ¼" guy termination that I have in junk pile. I have lots of used guys broken into non-resonant lengths, but I am guying with entirely new hardware and guy strand. This is not because the old guys are unsafe but rather to ensure maximum longevity. Galvanizing isn't forever.

Work, work, work

Constructing non-resonant steel guys is hard work and there is potential for injury. The guys are also heavy and therefore difficult to carry, lift and attach at height. For these reasons many hams are happy to pay more for fibreglass or kevlar guys.

Even then the bottom segments of non-conductive guys are typically made from EHS to minimize risk of damage, whether accidental or deliberate. Break a guy and the tower will fail.

As of now the first set of guys is ready to go. The other 3 sets are partially complete. I am delaying the rest of the cuts until the first set is installed so that I can minimize waste once the long lengths from the non-resonant upper sections to the anchors are cut to the actual required length. Making guys is tedious work so I make it more palatable by doing a little at a time.

One thing I've realized is that I will almost certainly need another 500' reel. Since the 2,000' in the 4 reels I have is too close to the total length I'll need any amount of waste will cause a shortfall. That's okay since I can use for the rest of the 5th reel in the future. Reel remnants can be used to make short non-resonance lengths for a future tower. Yes, I do have another tall tower in my plan.

Next steps

The tower is currently two sections high. Additional work was necessary once the gin pole and lifting method were tested and found wanting. Other issues have also cropped up. I'll talk about these in later articles since all of it is relevant to anyone contemplating putting up a guyed tower.

And I still have 8 sections to paint. I am hopeful of getting the tower completed this month.