As the so-called polar vortex descended upon us before Christmas, bringing my late year antenna projects to an abrupt halt, I could do nothing but wait it out. Over the holidays I could have done quite a lot indoors to progress matters while waiting for the weather to improve but the reality is that I did very little. I needed a rest.
Now that the weather has improved and my enthusiasm is perking up it is time for my annual look back and plan forward, something that has become a regular feature of this blog. Writing it down may do more for me than you, by forcing me to face certain truths about what I can do and what I should or should not attempt.
Hopefully readers will gain something from it as well, in particular those who have ambitions to improve their antenna farms. If this sort of article bores you I won't be offended if you choose to skip it. Perhaps I'm the only beneficiary is me. Putting plans in writing forces me to carefully think and decide whether the plan is doable and encompasses my interests and capabilities.
With that introduction let's plow onward.
What went wrong
Without question the most vexing item to plague me in 2017 was the necessary time to raise the big tower. There were a few things that caused the delay:
- Our wet spring was a record breaker. Excavation and below surface work could not be resumed until June. It was originally slated for late 2016 when an early winter storm interrupted the work. If that had been done the tower would have been raised months earlier.
- Let's face it, we're all getting older. There are fewer hams willing and able to help out than in the past. The situation is not getting better. I nearly succumbed to hiring the work out professionally even though I am fully capable of working on the tower. The friends who did come out to help were a real blessing. Even so they are limited in how much time they can spend here. Excellent weather was wasted when they could not make it.
- I care about doing a proper job. That entailed quite a lot of research, backtracking when I was unsatisfied with a tool or procedure, and long hours. On the plus side I am have no fears that the tower will come down in the first serious storm to come along. Since maintenance is the bugaboo of large antenna farms it pays to get it right the first time so that you don't have to redo it again and again.
- The active flora and fauna in a hay field create their own hazards. Wading through the high hay inevitably means dealing with ticks until early July at least. After that the black flies, mosquitoes and their larger cousins were so fierce as to frequently drive me indoors. Even if I cleared the field it would only reduce the tick population and help not at all with the rest. That would also annoy my neighbours who rely on the hay to feed their livestock.
Unfinished business
Although much of my 2017 plan was not completed there are a few projects that were started and then rudely interrupted. Weather was the main culprit. Cold, windy, snowy conditions hit fast and hard in December and did not let up. Apart from a few warm days recently the bitter conditions have resumed. The following items must wait for spring to arrive.
I had hoped be far enough along with construction of the 80 meter array that it could be used as a simple vertical over the winter. I succeeded with putting in the screw anchors for the guys just in time. When the weather warmed I stood up the first two tower sections and used rope as temporary guys. When I returned the next day to finish insulating the legs from ground I discovered that two of the screw anchors had moved. After further testing I decided that the anchors are inadequate for the prevailing soil conditions; the sub-surface soil turned into a slurry that demands deeper anchors with more bearing surface. That job is not practical in the extreme cold.
Cable burial had to be deferred when the frost penetrated the ground and didn't relent. Until April I can only hope that the deer don't abuse the Heliax buried under the snow and ice. All of the cables are suitably rated to survive the winter.
Terminations of the many runs of Cat5 control cable are open air rather than sealed in boxes at the towers. The few connections needed right now are manually spliced and roughly weatherproofed. Fine work of this type is too difficult in cold weather since much of it must be done with bare hands. The gel-filled cable can handle a moderate amount of moisture exposure without damage.
80 m array
The 80/40 meter fan inverted vee is temporary and will come down later this spring. I want it for long enough to compare it to the 80 meter vertical array that I am building, or at least in its preliminary omni-directional (single element) configuration. This is necessary intelligence to predict the array's performance and determine whether I still need a horizontal 80 meter antenna for short path and select DXing conditions.
The design of the 80 meter vertical yagi array has refined and compared, on the computer, to the 4-square array for a range of ground types and radial systems. I plan to devote an article to the revised antenna within the next month.
Design of the switching system has lagged. It's simple enough but it has to be fully specified and then built. The feed line and control cable to feed the array is ready to be installed once the weather improves. These, too, require trenching and burial.
I expect to have a horizontal antenna for short path work to complement the vertical array. I haven't yet decided exactly what and where. There is a dependency on high band yagis for which I want to avoid destruction interactions when they are on the same tower.
New tower
As I reread my plan for 2017 in preparation for this article there was one item that had me laughing: putting up a second big tower. In retrospect my optimism was, to put it mildly, misplaced. Yet for 2018 this is back on the table. Indeed without a decision my antenna plans cannot be finalized. That is, what do I put where?
There are considerations of stacking and interaction to be thought through. Otherwise I'll find myself putting antennas up then taking them down again within the year. That amount of churn may be acceptable for this winter on the existing big tower but it should not become a habit!
If it does go up it will be placed approximately south of the house in the spot reserved for it in my original site plan. This location has its good and bad points with respect to antenna interactions between towers. The main negative is that yagis on the towers will in certain cases point at each other when working Europe or the US. On the positive side this is an ideal orientation for low band wire yagis by running a rope between the towers.
Should the tower go up I already have one in reserve at an attractive price. I haven't bought it yet and the seller will give me first refusal in the unlikely case another buyer appears. The tower is identical to what I already have -- Leblanc & Royale LR20 surplus broadcast tower. I can use the same tooling to raise it and custom attachments will fit both.
It will not be as high. My aim is between 120' and 140' to allow stacking on 20 meters and 15 meters. The existing tower can then be dedicated to 40 meter antennas and then either tri-band yagis or 10 meter antennas. Wires antennas for the low bands will fit in somewhere. It is common practice for those with two towers to put 40 and 10 on one and 20 and 15 on the others to minimize interactions. In addition the 20 and 15 meter antennas tend to point in the same direction for much of the time, and this arrangement is helpful in that regard.
My decision on the tower is pending. There is more to think through before committing to it this year.
Yagis for the high bands
I had big plans for yagis on the big tower last year. Instead all I could do was put up the tri-band yagis I had on hand in the rush before the winter closed in for good. What I have is effective though limited in capability and flexibility. High band yagis are now a priority.
For the next 3 years I can get away with nothing more than what I have on 10 meters. All the openings are marginal and fleeting, and therefore addressable with a tri-band yagi up high and another down low. Indeed it is likely that I will still have a tri-band yagi on top of the big tower rather than a mono band yagi (or yagis). If I get another tower up then I can alter this plan. But if I do that I suspect I'll have little time (again) to build and raise antennas.
This brings us to 20 and 15 meters. Yes, there are other bands up there -- 17 and 12 meters -- which are not contest bands and therefore lower priority. Assuming I have no more towers this year I want to get at least one long boom 20 meter yagi and two on 15 meters fixed on Europe, and if I can I will make one or two of them rotatable. Alternatively I can pick up a cheap TH6 on the used market and stack it with the top TH6, substituting it for the Explorer 14 up ~115' (34 m).
The 5-element 15 meter yagi I designed for the boom tubing I have on hand is still a possibility. So are other options. This is a decision I must defer for a while longer. What I will most likely have to choose between is mono-band or tri-band yagis but not both since having both near each other cause unwanted interactions.
The bottom line is that I must remain flexible for the next several months until other plans solidify. Rather than overreach as I did in 2017 I will be pragmatic and seize opportunities as they appear.
40 meter challenge
I am shelving plans for a full size 3-element yagi on the big tower. I may do so eventually but not until I am truly ready to tackle a project that large. Instead what I'd like to do this year is to build a full size fixed 3-element yagi at ~80' (25 m) switchable between northeast and southwest. This will give me excellent coverage of both Europe and the US under most conditions.
A fixed yagi simplifies design, construction and installation. If all goes well I can put a similar antenna up top next year or later. Stacking the two is a possibility if they are sufficiently similar or identical. I expect the XM240 to remain on top for at least this year. It could be moved elsewhere, possibly converted to a W6NL Moxon for increased agility on 40 meters.
My preference for the fixed yagi is to use dipole tubing elements on a boom of at least 40' (12 m). A wire fixed yagi is less desirable due to the decreased average height and clutter in the hay field. Of course the first problem can be remedied by raising the apex, though at the expense of interactions with planned side mount yagis for the high bands above it.
I have most of the aluminum on hand for the boom and element centres, but not the smaller sizes. There are numerous other construction details that I need to work through. I don't mind spending some money on an experiment provided it doesn't get out of hand.
I will rework earlier models of wire yagis, shortened element yagis and full size yagis for now, and leave the final decision to the summer with construction slated for late summer or early fall.
Receive antennas
The Beverage I put up last winter continues to perform exceedingly well. Unfortunately it is only useful for working Europe and other regions in that direction. For contesting that's still a lot since it is a very productive path. Now my problem is all the other directions. There are several options that are compatible with my situation.
I have ruled out a vertical circle array. They are expensive, complex, can only be optimized for one band and require pre-amps that (according to others) often overload in the presence of a kilowatt on another band. This is unfortunate since they are reported to work better than Beverages.
Although simple and cheap, high performing Beverages have their challenges. For one, installing and maintaining them in the bush where I most want to put them is difficult, trees fall on the wire (this has already happened though without serious damage) and having enough of them to fully cover the compass without encountering siting problems and common mode risks due to the coax running from each to a control box. I will need to design and build a control box and remote switch.
I am currently investigating reversible Beverages to reduce the magnitude of the problem. Since running parallel wires through the bush is really difficult I am tentatively planning to experiment with a reversible Beverage made out of coax. It will either be east/west or north/south. Achieving good balance in the transformers seems to be the key requirement to ensure good directivity. I can do this while the weather is frigid, only risking frostbite!
If it works well I'll do more of them, though possibly not until the fall.
Station automation
Remote antenna switching, automatic antenna selection when changing bands, rotator control, filter selection, SO2R and more fall under this topic. That's a lot to do. I've begun some of it with a remote 8x2 antenna switch, although with a manual selector in the shack. Automation is not only convenient but also necessary for effective contesting when SO2R and multi-op.
I don't expect to get very far this winter. Since I plan to mostly build rather than buy the control systems I have purchased an Arduino and accessories to prototype simple items such as band decoders, antenna selection and control of the prop pitch rotator. Design of the systems and integration with the station are the major challenges. Writing the software is straightforward since I have done quite a lot of commercial software development and the academics to back it up. It should be fun.
I am as yet undecided whether to build or buy, or have a mix of both. It's a question of time versus money and customization to my own needs and wants.
As a consequence of automation I will to consider the impact on amplifiers and antennas. I will have to decide to spend more on a broadband solid state amplifier (or two) or have to fiddle with their tuning if I opt for cheaper and more robust tube amps. Antennas should have low SWR across the band for automation to be simplest. Otherwise broadband amps will complain and both transceivers and tube amps will need to be adjusted when changing bands, changing frequency and switching among antennas for the same band.
For the winter I will mostly stick to experimentation and prototyping, aiming for implementation in the autumn.
Amplifiers
This is the year I intend to return to QRO with at least one amplifier. There is no definite schedule. I will react to opportunities as they arise. Two amplifiers will eventually be needed for SO2R and multi-op contests. Two 240 volt circuits will have to be installed.
Choosing those amplifiers will be challenging. Ideally they will be solid state, no tune amplifiers capable of full power at an SWR of 2. They can be expensive. Amplifiers that require tuning, including economical tube amplifiers on the used market, are more flexible.
The latter would require extensive station automation so that band and antenna switching only requires setting the dials on the amps, otherwise time is wasted and costly mistakes are more likely.
VHF
If time allows I'd like to put up a 2 meter yagi on the Trylon just below the 6 meter yagi. That will serve me well for playing in VHF contests and occasional DXing. The original plan to use my roll of AVA7 (1-⅝" Heliax) for these antennas has changed. I will instead reserve that coax for the new tower to reduce loss on the high HF bands. It's a matter of my personal priorities.
The VHF yagis will most likely share a single run of LDF5 Heliax with a switch on the tower. I have no compelling reason to operate on 2 and 6 meters at the same time.
Last but not least: self improvement
Building a world class antenna farm with equipment and station automation to match is not enough. If you were to put a typical competent contester at the controls of such a station they would lose. Every single time. Too many imagine that if they had a big station that soon the walls would be covered in plaques. Not so.
Contesting is a skill that requires talent and constant practice. In that respect it is no different from an elite athlete or a highly performing tradesman or professional. It only seems easy in our imaginations. Skill improvement and operating techniques are beneficial for the little guys as much as for the big guns. Do not excuse yourself from making the effort.
That is a roundabout way to say that I am becoming a major impediment to better contest results. Although I have extensive contest experience and would even class myself a good operator there just is no comparison between myself and the upper ranks of the contesting world. I will have to improve. That became particularly clear to me this past weekend in the NAQP CW when I found myself in a team with a few of the country's foremost contesters and competitors in the forthcoming WRTC 2018. It was a humbling experience.
Operating a big station is very different from doing a contest with low power (including QRP) or modest antennas. The required intensity is unrelenting. As one big gun told me: you always have to be running. You have to be there CQing or the casual operators won't have an opportunity to call you. With a big signal your log will fill with QSOs and multipliers without scouring the bands.
They do of course also hunt for QSOs and multipliers, but they do so concurrently on a second rig. SO2R is mandatory. Liking SO2R and running is optional, but you must do it. I do not yet have the equipment or skills to do SO2R. That is in my 2018 plan. First I will start with simulations then advance to smaller contests. Even if I never equal the best at the craft (likely) my score potential will greatly improve. Station automation will support what's needed.
Old dogs can learn new tricks. Never stop learning.
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