Friday, January 26, 2018

Phantom QSOs

I live in an RF quiet environment. Or at least I do now that the local utility has fixed an intermittent source of power line arcing. Because it's so quiet I hear things that others do not. Indeed I can hear quite a few stations that cannot here me at all, which is especially true on the low bands. For example, in the run up to CQ 160 contest I could copy many European stations on my northeast Beverage a full 2 hours before sunset.

Having decent antennas does not compensate for being -10 to -13 db from the QRO of many (most?) stations on 80 and 160 meters. I also have to contend with the fact that the vast majority of stations do have local QRN that raises their noise floor, making it difficult to impossible to hear similarly equipped stations. In severe cases they can copy no one. A good recent example was the 6O6O DXpedition from Somalia who often had such strong QRN in Mogadishu that they simply shut down for hours at a time.

Unfortunately QRN from many sources in our modern civilization has become unavoidable. For the majority in urban and suburban locales it must simply be dealt with. It is no surprise that many stations, and not just on the low bands, cannot hear many of the stations that call them. QRO helps them to be heard with the small antennas they can fit within their properties, but that helps not at all on receive. Nulling loops and other compact directive receiving antennas cannot perform miracles.

As a result they have difficulty working the DX or contest QSO they are chasing. It is perhaps no surprise that some will take shortcuts to achieve their goals. By this I do not mean the cheaters using remote receivers that are easily accessible over the internet -- that's an entirely separate discussion. What I mean are those who complete their QSOs with a wish or a prayer. Let me give you a few examples.
  • In the 160 meter Stew Perry Top Band Challenge there was one European station I called that managed at first to successfully copy my VE3 prefix and nothing else. This QSO would be a challenge regardless since I entered as QRP (5 watts). After a few more tries he started guessing. I attempted to correct his guesses, which he also couldn't copy. Eventually he settled on a particular call and stuck with it, going so far as to imagine the exchange and log it despite my repeated attempts to correct him. I didn't log the QSO.
  • Several times while tuning 160 and 80 meters CW I would come across a QSO between a North American station and a DX station where one or both has difficulty copying. Whether it's QRN, local QRM, a power difference or an antenna difference I couldn't know. I can copy both perfectly well which gives me a front row seat to what follows. One station sends the incorrect call and other can't tell it's incorrect. They proceed to complete the QSO after numerous turn overs, with one or both call signs incorrect! I've heard the same with contest exchanges.
  • In a DX pile up there will occasionally appear a caller who obviously does not hear the DX station very well for whatever reason. I hear a lot of this on split operations since I have dual receive, with one receiver to each side of the headphones. That operator proceeds to imagine that the DX has responded to him, despite (obvious to me) that it is another station that the DX is responding to. Usually there is some similarity between the call signs, which creates hope for our intrepid DXer. The phantom QSO is completed and logged without the DX operator's awareness.
As I said this is more common on the low bands although it does happen on higher bands. Hope springs eternal, I guess. Be sure that this doesn't happen to you. If you do not positively copy the other station sending your call sign and exchange don't let your hopes and imagination run wild. You will be disappointed when the QSO doesn't appear in their log.

Sunday, January 21, 2018

Sound of Silence: QRN Eliminated

Back in December I mentioned (and showed a picture) of power line noise I have been experiencing at times throughout 2017. Now it's gone. To refresh our memories here is the noise on 6 meters with the yagi pointed directly at the noise source.

That's bad, real bad. As the frequency is decreased the noise gradually declines in signal strength with increasing loss of pulse definition. On 6 meters through 15 meters the noise could be mostly removed with the noise blanker, at the expense of inter-modulation distortion (IMD) products. This gets particularly ugly when faced with contest and pile up conditions.

Interestingly there was no impact on 80 or 160 meters. On 40 meters the yagi saw the noise as an deterioration of the noise floor, but not whten using the inverted vee.

Now the noise is gone. From the discussion I had with the utility crew I suspect it will not be back.

This is an exceedingly uninteresting picture, and it's just how I like it.

I have to say that the local electrical utility, Hydro One, was very responsive and helpful. This is welcome since we have among the highest electricity prices in the country. On top of that we face high distribution fees in our "rural, low density" township.

As a general rule utilities like to find and fix problems like this one. What they don't like is wasted labour costs spent searching for and not finding the source of the problem. This is why it is helpful to first localize the problem before calling them out. The intermittent nature of so many power line equipment problems can then be eliminated as a time waster. The crew lead told me that there is quite a lot of old and problematic equipment out here that they would in any case like to replace. My call had the effect of giving them a reason to do so.

I did not localize the problem since I am not equipped to easily go out with portable equipment that can find problems like this one. What I could do was accurately determine the direction from my house. In our low density neighbourhood this was enough since there is very little distribution equipment compared to towns and cities. In fact I could point them directly at the most likely culprit.

Although the noise was not present when the crew arrived with their bucket truck they went right to work. They found and replaced two cracked insulators, isolated the lines from rotting wood posts and replaced old switches just in case they were contributing to the problem. As they worked the noise appeared, disappeared, came back in spurts and then disappeared for good. I could listen as they worked since the power wasn't disconnected on my segment of the distribution network.

Then they switched off my power and went north to replace suspect switches at two other transformers. I have had weak power line QRN in that direction a few times so perhaps that will also disappear. Time will tell. Is there still some power line QRN? Yes, but just weak source or sources that are not serious problems. At least not at present. As equipment ages and deteriorates the future appearance is more a matter of when not if.

Rural distribution is typically 14,400 VAC, twice that in urban areas. It can run as high as 28,800 VAC. The higher voltage is more prone to causing arcs when equipment deteriorates. I don't know the distribution voltage on my road. I ought to have asked.

Now I have one less worry when I switch on the rig. The only serious noise remaining is from the Ethernet cable drop from my terrestrial wireless ISP antenna. I may deal with that later this year. It is now a minor problem since I mostly use the antennas on the new tower which are quite a lot farther from the house. All the LED lighting I have been installing has been clean, as is the new heat pump. A year ago I replaced a dimmer switch that created a lot of QRN on the low bands.

I am getting closer to having a QRN free QTH. Listening here in the relatively empty farm and bush country is wonderfully quiet. You can't work them if you can't hear them. Now I can hear them. They don't always hear me, but that's to be expected.

Thursday, January 18, 2018

2018: Unfinished Business and More

2017 was a big year at VE3VN, though one with even bigger objectives. In January of last year I had just topped the Trylon with a small tri-bander and a 40 meter yagi and then was left spinning my wheels after the aborted first attempt to plant the foundation for the 150' tower. Ongoing delays in putting up the big tower pretty well defined the entire year. My ambitious objectives for 2017 were only partially fulfilled.

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.
During the quiet times between bouts of tower work I did quite a lot of antenna modelling and exploration of physical design alternatives.

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.


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.


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.

Tuesday, January 9, 2018

Antennas on the Big Tower: How They Play

I now have sufficient experience with my new tower and antennas that I can begin to see how they perform. This is important in forming my plans for the future. None of the antennas on the tower is intended to continue for the long term. As a recap these are the currently deployed antennas:
  • XM240 2-element short 40 meter yagi, rotatable at 47 meters
  • TH6 tri-bander, rotatable at 44 meters
  • Explorer 14 tri-bander, fixed northeast (Europe) at 34 meters
  • 40/80 meter fan inverted vee, broadside to NE/SW at 32 meters
  • 160 meter t-top wire vertical with 8 x 30 meter radials, 20 meters from the tower
Heights are correct to ~1 meter. All main runs are Heliax (3 x LDF5, 1 x FSJ4) plus LMR400 to the lower antennas and RG213 to the 160 meter antenna. Coax from the outdoor 8 x 2 switch are LMR400 Transmission line loss is very low and not a significant factor for any of the antennas.

Power has been 200 watts (FTdx5000) in daily use, and 5 (KX3), 100 or 150 watts depending on the contest and entry category. My first take on performance was after CQ WW CW, before the TH6 and XM240 were connected. I expand upon that here with more on-the-air experience and with all antennas in operation.

Note on S-units

Do not interpret S-unit differences in the discussion below in decibels. The S meter on almost every amateur receiver is not linear with respect to decibels per S-unit and even nominal decibels per S-unit are not the same among receivers. The "standard" 6 db/S-unit is mostly a fiction. Even the more typical quote of 4 db/S-unit is not reliable.

I therefore do not attempt to estimate decibels from S-units when comparing antennas. In any case signal strength over time on any ionospheric path is too variable for the purposes of good precision.

So don't look for quantitative measurements here. My observations are informal indicators of relative performance. This is nevertheless useful. Exact antenna measurements on sky wave signals are hard to do. Really hard.

160 meters

The wire t-top vertical performs exceptionally well for such a simple antenna. It shows what can be done when you have a 43 meter tall support to work with! It's been used in 3 contests so far -- CQ WW CW, ARRL 160 and Stew Perry -- and casual DXing. I am pleased its performance. But how good is it?

The best test so far was the Stew Perry Top Band Challenge. Many stations with good antennas operate with QRP since there are significant bonuses to both parties in the QSO and the points multiplier is especially rewarding on long DX paths. Looking at the results so far I did well in the category despite being on for only 5 hours. I worked as far as eastern Europe, a similar distance to other QRP stations with good antennas.

In daily use I find that I can crack small pile ups even though many or most stations are running high power. Most hams have difficulty putting up an effective antenna on 160 meters and it shows. With just 8 radials a simple near full size vertical is very competitive. I now have 62 DXCC countries worked on top band from casual and contest activity.

This antenna is especially useful as a base line. It allows me to calibrate performance against others with better antennas and therefore make an informed plan for a permanent antenna. More receive antennas are needed before I increase power to a kilowatt since I can see that I will only attract callers that I would otherwise not hear. That's a good problem to have.

80 meters

This band is where I believe I have seen the smallest performance improvement. It's the same inverted vee I had at lower height, now combined with a 40 meter inverted vee for dual band use. The previous apex was 19 meters compared to the current 32 meters. It certainly works better although the improvement is incremental.

Horizontal antennas on 80 meters need to be higher than where I have it. Consider that λ/2 is 40 meters, and at its apex height of 32 meters the inverted vee's effective height is likely no better than 25 meters, or only a little more than λ/4.

A proper comparison cannot be made until I at least have the driven element of the 80 meter array operational as an omni-directional antenna. For now I have to be satisfied with good, not great results. It has been good enough to work VU and other difficult to reach DX with just 200 watts.

40 meters

This is a band where height makes a substantial difference. Right now I have three antennas on 40 meters, the two on the big tower and the multi-band inverted vee at 19 meters on the smaller tower. It is only on a small number of nearby paths that the lowest antenna is better so I will restrict the discussion to the high inverted vee and rotatable XM240 on top of the big tower.

Before sunset the inverted vee is often stronger towards Europe though not always. It's important to switch between the two to find what works best. Once it is dark there is no question that the yagi is always the best choice. Since the F/B is poor it can also be used most of the time to work Europe and North America without bothering to switch to the inverted vee, even though domestic signals may be stronger on it. Short paths are already strong enough except for the smaller stations.

On intermediate length paths such as to Europe and the Caribbean the yagi is at least 2 S-units better. Where it really shines is on the longer paths. For example, long path to east Asia in the early evening can be better than 5 S-units better on the yagi. This is no surprise. With 100 to 200 watts I have had little difficulty putting countries such as BY, JA, 9V, YB, UA0, HL and others in the log. Working 6O6O was more difficult but it's in the log. South America and the Pacific, and the Antarctic, are typically 3 to 4 S-units better on the yagi.

Perhaps the biggest problem with the yagi is that the prop pitch rotator turns slowly: ~0.6 rpm. You really have to think whether it's worth the time to catch one multiplier. Most of the time it's faster to use the inverted vee and have to call several times to get through.

30 meters

While I did not put up a new 30 meter antenna I have one nevertheless. Just as the 80 meter inverted vee worked well on 30 meters, the third harmonic with a tuner, it still works the same at its new height and form as a 40/80 inverted vee.

Unsurprisingly at 32 meters height it compares favourably to the multi-band inverted vee up 19 meters on the shorter tower. The difference ranges from 1 to 3 S-units depending on path and distance. Noise pickup is lower since it is much further from the house. I now rarely use the lower antenna on this band.

20 meters

Of all bands 20 meters is the most enigmatic when it comes to my current selection of antennas. I have in effect 4 antennas on this band, from the multi-band inverted vee up 19 meters to the TH6 up 44 meters. Path length, direction, time of day and overall conditions determine which antenna works best.

As I've discussed before the Explorer 14 fixed on Europe still does pretty well for working the US since the F/B is not great on 20 meters. Three elements on such a short boom is far from ideal. Even so it can be very useful by limiting the necessity of switching antennas, and of having a second antenna pointed at the US much of the time. The situation will change when I redo the antenna later this year.

Despite the lower height the Explorer 14 almost always delivers the best signals from Europe. On marginal opening the higher antenna does better. The performance difference is 1 to 2 S-units most of the time, but is occasionally greater.

On other short to medium length paths the rotatable TH7 works quite well despite being much lower at 21 meters height. Even to the current 6O6O DXpedition the Explorer 14 and TH6 are about equivalent. In this case I favour the TH6 because the better F/B is better at hearing through the pile up.

This selection of antennas, and nodes in the elevation patterns, make plain that the ionosphere determines the path, not the antenna! On 20 meters 44 meters (2λ) can be too high much of the time.

As for 40 meters it is on the longer paths that the high antenna shines. Whether it's Asia, the Pacific or South America the TH6 is better than the TH7 by no less than 2 S-units and can be another 2 to 3 S-units better than that. On long path to VK and the Pacific the difference is remarkable. Signals pop out of the noise on the TH7 to almost S9 on the TH6.

Of course there is no need to always use the best antenna. Other than for the longest paths I will more often simply use the one closest to the correct direction, turn it and use it. Making the QSO is what matters, not burying the other fellow's S-meter.

Height clearly brings a new level of performance to my station on 20 meters. This bodes well for upcoming DX contests when I expect to increase QSOs and multipliers.

17 meters

There are two unintentional antennas for 17 meters on the big tower: XM240 and 40/80 inverted vee. Both are efficient and present good feed point impedance, although the rig's ATU is required for full power operation. That the XM240 resonates is no surprise since it is widely known that the antenna has a harmonic resonance near 18 MHz. Unlike full size 40 meter antennas the third harmonic resonance (3λ/2) is lower due to the effect of the loading coils.

There is good and bad performance on 17 meters with these antennas. The good is that they're much higher than the multi-band inverted vee up 19 meters. The bad is that the azimuth patterns are complex with multiple nodes and lobes typical of antennas operated well above their fundamental frequency.

As a result it requires switching among the three antennas to find the best signal, and then adjusting the tuner. This is inconvenient though acceptable for a non-contest band. For now I can live with what I have. A resonant gain antenna (yagi) on 17 meters is low priority.

15 meters

Most of the time the TH6 outperforms both lower yagis. It is rarely worse. This may in part be due to the low MUF and therefore low elevation angles on all paths at this time of year and solar cycle. It seems that every 15 meter opening is fleeting.

When the band is open to Europe I will swing the TH6 towards more distant shores and the TH7 towards the west or southwest, using the Explorer 14 for Europe. While not ideal for all openings to Europe it gives me the flexibility to roam all the high bands for multipliers with the TH6 up high and for shorter paths with the TH7 down low. This approach works well in contests.

On longer paths such as South America, the Pacific, the Indian Ocean and east/south Africa the high antenna is superior to the TH7 by 3 to 4 S-units. Compared to the Explorer 14 to the Indian Ocean and east Africa (about the same bearing from here as southern Europe) the difference is smaller, usually less than 2 S-units.

10 meters

My experience on 10 meters with the new antennas is limited due to conditions. When the band has opened to South America, ZS and ZL the high TH6 is the clear winner by 2 to 4 S-units or more over the TH7 at 21 meters height. With no European opening on 10 meters this winter I cannot yet compare the TH7 to the side mounted (fixed) yagi lower down by a full 1λ on 10 meters.

Indications are generally favourable for when conditions do improve, and they will do so as the winter progresses despite the low solar flux. Back scatter signals from US stations appear to be stronger as well on the high yagi. Again, this is as expected.

Where I go from here

The tower is high but the antennas are not the best. It is enough to show the promise but not deliver it, at least not yet. Three more things have to happen in order to put out a dominating signal.

The first is to replace tri-band yagis with mono-band yagis. Depending on the band and boom length an improvement of from 1 db to 4 db can be expected. The price to be paid is clutter on the tower, expense and management of interaction between antennas and with the guys. This is not a job you want to get right the first time.

The second is to stack those mono-band yagis. Depending on height, boom length and spacing the gain improvement typically ranges from 2 db to 4 db for two identical yagi and more by adding more yagis. The problems of expense, clutter and interactions are obviously worse. If one or more of the yagis in a stack can be separated and rotated the challenge is even more acute.

The last is to increase power. Running 100 watts in a contest with this antenna farm is competitive against others with similar power, but not with those using more modest antennas and a kilowatt. There is no easier and cheaper way to gain 10 db than to plug in a box and turn it on. Of course this is no help with receiving well or competing against those with high power and big antennas.

You might also wonder whether one or two S-units matters at all. For casual operating perhaps not. Where it makes a big difference is in contests, putting many more QSOs with smaller stations within reach and cutting through the QRM at the other end, especially within Europe. Your individual interests determine whether the improvement is worthwhile.

These are topics I will come back to later. I have decisions to make before I can proceed with my plans for 2018 and beyond. I intend to be modest in my ambitions. But for now I am on the bands and having fun with what I've built so far.

Saturday, January 6, 2018

Disappointing Pile Up Behaviour

The pile ups on the ongoing 6O6O (Somalia) DXpedition have been fierce. This is especially true in this region of North America since we have had fewer opportunities than many others. I expect to eventually work them though I have not yet done so. Unfortunately there is behaviour going on that particularly troubles me.

It's not the DQRM. Yes, there is DQRM as there seems to be whenever a rare station appears on the bands. It's ugly and I don't like it, but I can deal with it. It isn't the wayward who transmit on the DX's transmit frequency. We all make mistakes, and that includes me from time to time. It's embarrassing but you move on. Everyone discovers their mistake and corrects their transmit frequency, some later rather than sooner. The hurled obscenities are also regrettably routine and I don't let it bother me even though it reflects badly on all amateur radio operators.

No, this time it's something else. Every DXer knows there are those who will continue to call on top of the station the DX is attempting to copy. I don't mean those who do so unintentionally. It is easy in a pile up to not clearly hear the DX at all times or to double with them.

This egregious behaviour not only slows down the pile up it also delays the acquisition of a QSO by those creating the QRM for the DX operator. This should be so evident that any operator with an ounce of intelligence would understand that this is a bad idea. Many continue the practice despite zero evidence that the DX will reward them for their bad behaviour.

Again, this is routine in pile ups, regrettable as it is to see. Hams are people and bring all their human faults to the hobby. So we deal with it. What has me upset right now is a small subset of these persistent QRMers, the ones who ought to exemplify proper operating ethics.

I'm talking about contesters. Not just any contesters but those who regularly feature at or near the top of the results in all the major contests. They are well known. Too many call signs I recognize are repeatedly dumped on top of the station the 6O6O operator is trying to copy.

The guilty have excellent DXing technical skills, quickly finding the station the DX is responding to. That they then QRM the frequency with their high power and massive antenna farms is poor sportsmanship. That they do this persistently from on QSO to the next is outrageous. It is also embarrassing to have to say that some of these are hams I have met in person and there are one or two in my own contest club.

These are contesters I greatly respected and admired only 24 hours ago. Now I don't. I expect better from contesters, the members of my own tribe, so to speak. Superior operating ability and technical excellence in station design for some is seemingly not matched by their ethics and their treatment of others. That makes me sad and angry.

I am not going to name them. Even if I did I doubt it would help since humans are great at rationalizing and outright denial when caught in the act. It isn't even necessary since those chasing the DX can hear their call signs for themselves in the pile up. They persist despite knowing that everyone knows who they are and can hear what they are doing.

I don't have a solution. I can only hope I am overreacting and that the problem among elite contesters is less than I fear.

Tuesday, January 2, 2018

Closing 2017 With QRP

In advance of the new year celebration there were two contests I decided to enter: RAC Winter Contest and Stew Perry Top Band Challenge. The first was partly obligatory to contribute to the Canadian presence for the event, but also to exercise the new antennas. This was the first contest I've operated with the full complement of antennas I put up during the year.

For Stew Perry my interest was different. As an experiment I entered as QRP to see just how well my 160 meter antenna would perform against others under similar conditions. Although designed and built as a temporary solution it does do pretty well, putting me well on the way to top band DXCC and contributing nicely to contest totals.

So I resurrected my KX3 and plopped it front and centre on the operating desk. It looks a little out of place next to the FTdx5000 and other equipment! The KX3 has been boxed up since before the move in 2016 and this seemed a good opportunity to get use out of it. Power on the FTdx5000 only dials down to 10 watts, which makes it unsuitable for QRP.

I set it up the day before the RAC contest to get it integrated with the PC, keyer and antenna switch. Memory is a tricky thing so I had to take 15 minutes to familiarize myself with the controls once again. I had to think for a few moments to recall which buttons to press to turn it on. I took the opportunity to update the firmware which has gone through several releases since 2016. In comparison to some other transceivers Elecraft makes the process absolutely painless.

My activity in Stew Perry was limited, by intent. This was an experiment rather than a serious contest entry. After the RAC contest ended and the evening meal I moved a few cables and fired up the KX3 on 160. Operating time as ~5 hours total, 4+ during the evening and then a little more in the hour before dawn.

I wrote a lengthy soapbox comment for 3830 score submission, if you want to read it. For the blog I'll keep it brief.

The antenna worked very well with only 5 watts. I didn't work a lot of DX, yet that I did work DX put a smile on my face. My furthest contacts were PJ2T, S5, HG and SP. I got a partial copy from a Russian station that would have been a real coup had we been able to make the contact.

Looking at the incoming reports I can see that my performance was on a par with the best results of QRP entrants from this part of North America. That's useful feedback. Now that I know what this simple wire antenna can do, it becomes a baseline from which to plan a permanent antenna for 160 meters.

What I also learned (or relearned) is that the KX3 is not up to the challenge of a band full of exceptionally strong signals. Operating was frustrating at times. Receive filtering is terribly inferior to any competitive base station transceiver. The critical issues were filter skirts at the narrowest settings and opposite side band bleed through (single signal reception). On the plus side the audio coming out of the headphones was an absolute pleasure to hear.

Despite the negative notes the KX3 is a fantastic little rig. It is perhaps unfair to compare it to its bigger cousins. On the hand I firmly believe that every comparison should be against the very best available, no matter the price or size. I still like and I am keeping it. Should my interest in occasional QRP operating wane I will revisit this. Elecraft sells companion products to increase power to 100 watts and make it more of a base station rig. I don't see the point; better to buy a high performance base station rig if that's what you want.

With these contests 2017 is in the rear view mirror and my thoughts turn to 2018. Ideas and plans are slated for articles later this month.