Friday, October 29, 2021

Lifting the 10 Meter Yagis

Lifting the newly built 10 meter yagis onto the tower was done by tram line in a fashion no different than I've done before. However, I feel that it is worthwhile to review how it was done and to mention a few noteworthy points about the lift and antenna behaviour. A full assessment of their performance will have to wait until I gain more experience with them which, as you'll see, is not yet possible. 

Both of the 10 meter yagis were tuned using the same rope tram line used to lift the TH6 to its new rotatable side mount at around the 75' level of the 150' tower. The tram line and haul rope were then raised 40' and used to lift the lower yagi to its perch at 110' (on left). The side mounted lower yagi is fixed to Europe. 

The lift of the lower yagi was done without helpers. It was not difficult to achieve good balance and orientation for a small yagi and it is light enough to be raised by one fit individual. The lift was incident free so up I went and bolted it to the side mount bracket. That was the easy one of the pair.

To lower the antennas that were up top and to raise the upper yagi a steel tram line was anchored to a large and healthy tree in the bush at the opposite end of the hay field. I previously mentioned clearing a path to the chosen tree. Although not needed for raising this yagi, or for the preceding lowering of the TH7 and 40 meter dipole, using the tree was a trial run of the basic setup that I plan to use for raising the 3 element 40 meter yagi that is currently under construction. That's a big healthy tree, and a hefty chain to match.

As I briefly mentioned in a previous article, the TH7 and 40 meter dipole at the top of the tower were taken down earlier in October. Several friends came over to help on the ground and, as usual, I did the work on the tower. Only one friend (VE3KAE) was needed to raise the upper 10 meter yagi on the same tram line. For these higher jobs I prefer a helper even though in this case the upper 10 meter yagi is lighter than the lower yagi that I lifted on my own.

Notice the rope around the big tree? It is a safety line from the tree to the tram line cable termination. Winches are mechanical devices that can fail due to excess use and defects. Nothing is forever. When the tram line is at the desired tension, the rope is pulled tight and serves as a backup in case a problem arises. It does happen, as I can assure you from personal experience. No injury resulted in that incident (people or antennas) but it easily could have. Use a safety line.

Just because I like it, I included a shot of the upper yagi from the top of the 150' tower when it was less than 100' feet away (the tram line is 350' long, or 110 meters). Later I describe how I handled it when it arrived. The rigging for the tram ride is not always ideal for an easy connection to the mast.

The bracket for the lower yagi previously supported the TH6 that is now on a rotatable side mount further down the tower. I took the opportunity to improve the bracket and replace clamps that were showing their age. Although there are 5 elements squeezed onto a 24' boom, the wide director spacing of the optimized design allows the 10 meter yagi to comfortably fit on the bracket in any orientation without any element getting overly close to the tower.

There are nevertheless interactions, as I fully expected. For example, the SWR is not what it was when tuned. There are guys off the rear sides and one in front, towards Europe. Per my guy wire interaction model the interaction is likely to be primarily with the rear guys. I have not yet confirmed this in a model.

Although the guys are not terribly close (the picture is deceiving) and largely orthogonal to the antenna elements it takes little to disturb the pattern of a 10 meter antenna. The segments of the broken up guys are non-resonant on 10 meters but are large enough to couple regardless. I had a similar effect with the side mount 15 meter yagi but not the side mount 20 meter yagi. Size matters. I expect the antenna to perform well regardless since the impedance excursion is small and I know from other hams with similar installations and my own experience that gain remains very good.

I am unconcerned about a few minor lobes in the pattern since my interest is contests and a little radiation in various directions can pay dividends, and modest interactions don't reduce the forward gain by much. The minor lobes attract more callers without allowing too much QRM. Others with different operating interests might be more concerned. The only practical way to achieve a perfect pattern for side mounted 10 meter yagis (and for 6 meters and other VHF bands) is to use non-conductive guys.

Unlike the upper 10 meter yagi the SWR on the lower yagi is not what it was after the gamma match was adjusted at a lower height. I don't yet know how much of the change is due to tower and guy interactions and how much is due to me. The human body couples poorly but noticably on 10 meters. Antenna behaviour is affected by the proximity of my body (notice the reflection in the left panel).

The effect is reduced by standing vertically below the boom and by standing farther away. The good SWR of the upper yagi was not so good when I measured it the same way as I measured the lower yagi. The coax from the boom to the analyzer was only 2 meters long. The SWR on the right was measured when the antenna was at the top of the mast and I was at the bottom of the mast.

Now let's turn back to the raising of the upper yagi. Alan VE3KAE took a picture of me (on the left) as I took possession of the yagi at the top of the tram line. With the tram line slackened we lowered the antenna until the boom-to-mast clamp rested on the top plate of the tower. This was necessary so that I could move the chains and shackles for the tram pulley and haul rope onto the far side of the clamp plate.

The geometry of this rigging doesn't always make it easy to do the whole job with the same rigging. The large plate and integrated boom truss support made the transition mandatory. I was able to get one saddle clamp attached in this awkward orientation so there was no risk of an accident while I did the rigging. To save time I tossed no longer required chains and attachments to the ground. 

Always make sure to get your ground crew out of the way when you do this and only if you can comfortably send the material clear of guys and the antennas below. Stuff like this easily survives the 150' fall and it saves me the time and effort of carrying the rigging down with me. The steel strikes the ground fast enough that it is partially buried. On this climb I somehow knocked loose the little radio I used to talk to the ground crew and down it went. Unbelievably it survived the fall and still works!

With the antenna firmly clamped to the mast I rotated the boom so the elements were perfectly horizontal. I then adjusted the truss turnbuckles to level the boom. The turnbuckles are out of reach when the antenna is raised to the top of the mast. The next step was to remove the anchor plate (for the tram line and haul line pulley) from the mast, step the mast and hook a pulley to the top of the mast. The haul rope is threaded through this pulley down to the antenna.

It's a tedious process because I must then remove the steps to slide the antenna up the mast. Everything must be done with safety foremost, and that what takes the time. The procedure of the lift itself isn't difficult. I am deliberately avoiding details of mast stepping and mast climbing so that I don't give any ideas to overly enthusiastic readers. This is not a job for the tower novice.

With the rope pulled tight I loosen the mast clamps. While my friend pulls the rope I push the antenna upward. I again step the mast and follow it to the top. It's faster to remove the clamps and let the antenna climb freely, but it is not so easy to do the fine mechanical work of inserting the clamps (and not dropping hardware!) while perched at the top of the mast. So I do it the slower way.

To get the antenna to the very top requires rigging the haul rope to the bottom of the antenna. Otherwise you can't lift to the very top of the mast. Even so the rope jammed within inches of the top so we called it a day and I tightened the clamps, removed the rigging and climbed down.

I dress the cables accounting for the arbitrary direction the antenna ended up pointing. My home brew prop pitch motor controller allows infinite adjustment, and the direction pot on the tower has a 10:1 drive ratio, so that also allows essentially infinite adjustment. Calibration in the shack took 5 seconds.

The antenna works and it is ready for action. The lower side mount yagi will be without a coax connection until I build a 10 meter stack switch. It will make a triplet with the L-network 20 meter and 15 meter stack switches I built.

I'll close with a pretty picture. We are looking along the boom of the upper yagi towards Japan. The solar flux is high enough to work Japan on 15 meters and it won't be long before they are booming in on 10 meters. It is no accident that the 10 meter yagi project occurred this year: the solar cycle allowed me to delay until now, but no longer. 2022 is going to be a very good year for HF propagation.

Sunday, October 24, 2021

Headset Woes

I operate SSB from time to time even though it is not my favourite mode. My usual forays to phone are contests and DXpeditions. I periodically use my big signal to run DX stations on phone, for fun and a change of pace. Microphones are otherwise pushed aside or unplugged to tidy the operating desk.

There are several styles of microphone with which we are all familiar:

  • Handheld
  • Desktop
  • Boom
  • Headset

Handhelds are fine for the occasional use at the operating desk, but are more appropriate for mobile operators. Having to hold a PTT button is tiresome for long operating sessions and contribute to transmitted noise due to hand pressure and movement. For my style of operating a hand mic is purely for emergencies when my preferred mic fails. Most rigs include one so I have quite the collection.

Many HF operators love desktop mics. Quality is often excellent and they are suitable for both PTT and VOX. I don't like them because you have to hold your head still, as if it was in a virtual vice. That makes it difficult to fiddle with the computer and rig while talking and it is uncomfortable for long transmissions and operating sessions. It blocks keyboard access, takes up valuable desk space and blocks my view of the rig.

Boom mics share many of the characteristics of desktop mics but allow your head to remain upright because they can be positioned more conveniently. Decades ago, my friends and I used to tape small mics on swivel stands repurposed from desk lamps for contest operating. PTT is a foot switch or VOX. I gave up on them after my first experience with a headset.

Headsets are worn on the head and include headphones and a microphone in a single unit. Like many contesters, this is what I prefer. Headsets have significant advantages:

  • Do not impair vision and access to the keyboard and equipment
  • Consistent audio level and quality since no matter how your head or body moves the mic is always in the same position relative to the mouth

It is no surprise that there are a variety of headset options that are of interest or concern to hams:

  • Comfort when worn for long periods (typical for contesters and DXpeditioners)
  • 3.5 mm or USB connectors
  • Wired or wireless
  • Electret or dynamic mic element
  • Flat or voice communication audio response
  • Enclosed or open ear enclosures for the headphones
  • Servicability
  • Quality: longevity; resistance to abuse; reliability

Once the domain of hams and professional communicators, headsets are now used for e-games, video and voice internet communications, and call centres. Supply serves the demand, so the market offers an abundance of choices for those applications. 

Unfortunately the quality is often poor and price is an unreliable indicator of quality. Since most products are targets at internet and computer use, those of good quality may score low on our requirements. Products specifically made for hams and other communicators also have deficiencies. There are more choices than ever but few that are great.

Let's look more deeply at several of the options that are pertinent to HF operating.


Let's face it, most headphones and headsets are uncomfortable after several hours. For a contester that's a problem. When my head and ears are throbbing in discomfort, and sometimes pain, it is difficult to continue. There are very expensive headsets that are uncomfortable and there are cheap ones that are comfortable. Sometimes it helps to take my glasses off since it reduces a critical pressure point and my vision is adequate to operate the computer and radios.

One of the most comfortable and reasonably priced headsets with full ear enclosures is the Yamaha CM500 (pictured above). Many contesters agree. Unfortunately it has been discontinued and there is a dwindling supply. Although it is reputed to be robust that is relative. The mic on mine quit and it is pretty well impossible to service.

Many similar looking headsets are not as comfortable. The headband of some, but not all headsets can be spread to lessen the pressure. 

If the plastics used for the band or the ear enclosures are stiff or thin there is very little that can be done to make them comfortable. The comfortable plastic covers on many headsets wear out quickly because they are soft and pliable. This happened to my Koss SB45 headset, along with a broken wire in the cord (see picture at right).

Don't expect to be allowed to try on a pair in a store. Your best bet may be to ask your friends with similar operating habits for recommendations. Only ask those with fewer opinions and more operating experience.

Personally, I have always favoured open air headsets and headphones that sit on the ear without an enclosure. My ancient Heil headset is like that, and if the cord hadn't failed I might have continued using it. Most hams need ear enclosures to eliminate household noise, but if you can close the door of the shack that may be good enough unless you have amplifiers with big fan noise.


You will find that many headsets have a USB cable for direct connection to a computer. You can use these if your logging software or other application can route the audio to the rig mic and headphone connectors via the sound card ports. Contesters often do this since it simplifies station cabling, mutes the mic while playing voice messages, recording messages on the fly and support audio routing for SO2R. For example, the N1MM contest logging application. That may be difficult to do outside of contests and without specialized software.

There are adapters available to convert USB to 3.5 mm stereo for both headphone and mic audio. Otherwise you may prefer to choose headset with 3.5 mm plugs. Many older radios, and a few new ones, have unique mic connectors for which you'll need adapters.

The choice will depend on your station and your operating preferences. Be very careful to read the fine print before ordering or you'll waste your money.


Headset cords are a common failure point, and they often get in the way. It is inconvenient to be "tethered". Only some of the most expensive headsets allow cord replacement. You can try to replace or repair cords on other products if you have endless patience and you are prepared to employ destructive measures to pry them open, and try to reseal them afterwards.

Wireless headsets would seem to be desirable since there is no cord. The problem is that battery life is measured in hours, and that is insufficient for operating a contest. For some, the battery pack goes has to be placed in a shirt pocket. The other end of the wireless link is typically only for connection to a computer, and that may not work for you.

Mic element

The vast majority of headsets have a flat response. For "talk power" hams prefer a strong mid-range peak that accentuates communications at the expense of fidelity. Long ago the only good option was to select a mic element designed to do this. I had one of those elements for my first Heil headset. Special elements are no longer necessary since most high end rigs include a programmable equalizer. 

When combined with a speech processor the improvement in average power, and therefore being copied by others, can be quite impressive. There is no need to over-amplify or over-process the audio. If you do expect excess distortion and splatter.

What you never want to do is use one of those voice accentuating mic elements and an equalizer that does the same. Use one or the other. I prefer a flat electret mic for my headsets. Swapping headsets has no effect on audio processing and you have a far greater choice of commercial headsets. Leave the equalization to the rig.

You also need to consider the type of mic element. There are really only two that are of interest to us: dynamic and electret. There are still transceivers that only support dynamic mics, yet the majority of mics have an electret element. There are a few modern transceivers that have insufficient gain for the lower output dynamic mic, and for those you must use an electret element. 

Apart from gain, an important difference is that the electret mic requires DC power. Pretty well every computer sound card has this feature, as do many modern transceivers. For rigs that don't you'll need to buy or build an adapter that AC couples the audio and supplies DC bias to the element. The Yamaha CM500 includes a battery-operated adapter. I customized an adapter than connect a 3.5 mm stereo plug to the 8-pin front panel jack of Yaesu rigs, and taps the DC pin to bias an electret element and a capacitor to block the DC from the audio signal path.

Reliability and servicability

Perhaps the least reliable part of a headset is the cord. Every movement of your head makes it shake and it bends when you take them off, so that over time the thin wire fatigues. Thicker insulation and strain relievers help but do not cure the problem. Very few headsets allow cord replacement, or of any other part for that matter. Not even the plastic ear pads can be replaced when they inevitably wear out.

I have found that the cheaper headsets are not up to heavy use day after day. The cord becomes intermittent, the mic element fails or the plastic tears or crumbles. They are sealed units that cannot be opened without damaging them to a lesser or greater extent. There are expensive headsets that are easy to repair and replacement parts can be ordered. Unless you really like those headsets it is poor economy since several cheaper and often more comfortable headsets can be purchased for the same price.

I have looked around and canvassed fellow contesters and my reluctant conclusion is that headsets have a limited lifetime. They are perishable items, like batteries. When they fail, you discard them and buy another headset. There just doesn't appear to be a sensible alternative. There are contesters who have stockpiled several of their favourite headsets in case they need them fast and when they are no longer manufactured.

Since I have a strong preference for headsets in contests, my intention moving forward is to only use those headsets for contests. The rest of the time I will use other headsets, or headphones for non-voice modes like CW. Swapping headsets and headphones before and after contests is annoying but a practical way to extend their service life.

CQ WW is on the horizon

We are days away from the largest phone contest of the year: CQ WW. Since I have not been able to pick up the replacement CM500 a friend bought for me (we live far apart) I purchased another Koss 45 headset. It is less comfortable and the cord is flimsy, but from my experience they are acceptable for an 48 hour contest.

Although I don't intend to put in an all-band full-time effort, the rapid approach of CQ WW motivated me to act. So I went to a popular on-line site and put in my order. The headset arrived the next day and is now in use. If only the rest of my station was as ready!

I have been tardy with blog articles because I am exceptionally busy with tower and antenna work, and the weather isn't getting any warmer. I want the work done by mid-November. Expect more about those projects in upcoming articles.

Tuesday, October 12, 2021

Critter Protection for the 80 Meter Array

This is not the first time I've talked about critter damage to my 80 meter vertical yagi. The cables, wires and enclosures are close to the ground and, for some reason I don't understand, deer appear to enjoy chewing on all of it. At least, I think it's the deer, going from the marks of mastication on plastic components. Maybe they're curious or bored. Regardless of the reason, the unwanted repair work is aggravating.

The bouts of damage this fall motivated me to take preventive measures that I've been avoiding. There are temporary and permanent fixes, with the temporary ones to be changed to permanent when I have more time. I am very busy this month with other projects.

I'll step through the work I've done to give an idea of what I'm dealing with. Although one item is for safety and not critter protection, I'll mention it anyway. Let's cover it first.

All turnbuckles should have safety cables. The cables tie the guy to the ground anchor. If the turnbuckle fails the cable prevents the tower from collapsing. The tower in the 80 meter array is the driven element and it supports the parasitic wire elements. 

The guy tension is quite low, just enough to keep the tower stable for climbing. I've been meaning to get this job done, and after 3 years its time has come.

One disadvantage of safeties is that the turnbuckle cannot be adjusted without temporarily removing the safety. This is difficult on the big towers since the safeties are ¼" EHS. It is a struggle to route the tough, springy stuff through the eyelets and bodies of the 4 turnbuckles without kinking the cable. It is also a potentially dangerous task. Bent EHS that slips out of your grip springs back forcefully and can do serious injury. The ⅛" aircraft cable used for the 80 meter tower turnbuckles is far easier to work with.

The parasitic elements are sloped T-shaped wires per the original K3LR design. Both ends of the sloping wire (top of the T) are supported by ropes: one to the top of the driven element and one to the ground anchor. Tension on the ropes keeps the element in place.

Deer enjoy chewing rope. That was a surprise to me, but I'm no expert on deer behaviour. Cutting a support rope disables two directions of the array. The other two directions are impaired since all the parasitic elements will sag when one rope is cut. It is an easy repair, but an aggravating one to have to do (again).

The solution is the same as it is for towers guyed with non-metallic cable such as Phillystran. The bottom of the guy is steel and connects to the main guy at a height that is sufficient to avoid accidental damage from mowers, walkers, tractors and critters. Due to the slope of the element the steel cable needs to be at least 10' (3 m) long to be safe from curious deer.

The cables are 3/16" aircraft cable since it was loitering in my junk box with no other obvious use. In this specific application almost any size of steel will do. I did not cut the ropes to size after installing the steel cables in case I need them in the future. The deer are free to chew these trailing ends if they want. The dangling extra rope was attached to the steel cable after the picture was taken.

Protecting the exposed control cables, antenna wires and enclosures at the 5 elements requires cages. The cages must be non-conductive, anchored to the ground, allow rain and snow to drain, not encourage insects to shelter there and, finally, discourage curious animals. I have a few candidate designs in mind that I can build with material on hand.

The project is not difficult except that time is needed, and right now that is in short supply. As a temporary measure I did something that was fast, cheap and ugly. I wrapped all 5 elements in plastic sheet (yes, that includes the tower base!).  The black plastic is resistant to UV from my experience using it in other temporary weatherproofing jobs.

It is obviously a poor physical barrier since any animal can easily tear through it. What I am betting on is a visual deterrent since deer are not too smart. If they see a large black blob they will likely leave it alone. What they can't see probably won't attract their attention.

Hopefully this will suffice a few months until I can build a permanent solution. The plastic wrap is easy to remove should antenna repairs be required. It is held together with black electrical tape that is easy to peel off and then back on. If it tears, well, I have an endless supply of plastic sheet.

They have never chewed on exposed Heliax, which is exposed in numerous places and is much thicker than the cables and wires they have damaged. Apparently size matters, and that is why I am guessing the "big black blob" solution might work.

Speaking of Heliax, there is one more job to be done. Although no animal has attacked the many runs of Heliax exposed at ground level, in my enthusiasm I decided to protect the exposed Heliax to the 80 meter array. The underground run of LDF4 from the electronics at the tower base is only to the edge of the radial field. It connects to a long run of LDF5 that is mostly buried but overground near the junction due to trees roots and rocks.

I wrapped the exposed junction in chicken wire. Steel discourages critters, so even though the plastic outer layer can be touched through the mesh it is unlikely to suffer bites or chewing. Rodents might but they have yet to touch any wires and cables that are on the ground or shallowly buried.

Now I cross my fingers and hope that these measures will provide lasting protection. Clearly there is more work to be done, and it is a good project during winter when tower work is suspended. 

As an aside, here is a hint of where my time is being spent. Notice that the 150' tower has no antennas on top. The TH7 and experimental 40 meter dipole were taken down last week with the assistance of several friends. 

The TH7 will remain on the ground this winter and may be permanently retired. The 40 meter dipole was inspected to see that it suffered no stress fractures or other problems. It passed inspection so I am continuing with the element design to make the director and reflector for the 3-element yagi I am building.

The 40 meter yagi in particular is responsible for my lack of time for smaller projects this fall. I will soon be raising the 10 meter yagis onto this tower (one fixed, one rotatable) in preparation for the big 40 meter lift. More about these and other projects in future articles.

Tuesday, October 5, 2021

6 Meter DXing Using the Buddy System

In my 6 meter season wrap-up I mentioned that I and a couple of friends all passed the 100 country DXCC mark (confirmations) on 6 meters this year, and that called for a celebration. With the gradual rollback of pandemic restrictions that became possible and we had our get-together in late August. 

Sharing the accomplishment with friends, when all have the same accomplishment to celebrate, is particularly enjoyable. It is not really coincidental that the three of us passed the DXCC milestone in the same year. As I've said on multiple occasions, the digital modes changed the DX game forever on 6 meters. Despite my strong preference for the "traditional" modes, FT8 in particular is well suited to the brief and elusive nature of most long DX paths via sporadic E propagation on 6 meters, and its occasional tie-up with TEP to reach across the equator. 

We are shown at the QTH of Cezar VE3LYC (on the left) having a BBQ, complete with a variety of Romanian treats. The latter was particularly welcome since my family comes from Romania and with the passing of my parents it brought back many pleasant memories. The picture was taken by Lucy, Cezar's wife, who is to be thanked for the wonderful meal we shared.

Paul VA3LX is in the centre and I am on the right. Both Paul and Cezar are in FN14 and I'm in FN24. Both of them live near the city of Kingston on the shore of Lake Ontario. Cezar and Lucy's home in on the very picturesque lakefront, just upstream of the city and the Thousand Islands. This is a rare photograph of yours truly since I rarely show pictures of myself. Readers and more interested in what I'm doing, and not on me.

In that light I want to turn my attention to the DX buddy system. It has slid in importance over the years as DX spotting networks, RBN, PSK Reporter and other online systems tells us where and when to find the DX. These remove a lot of the drudgery of finding rare DX. However, many DXers prefer to do the work on their own, to find the DX without outside assistance. Regardless of approach, you still have to work them.

In the buddy system, when one of the group's members notes the DX station or path opening, they spread the news to their DX buddies. This can be done in many ways, and for the three of us it has mostly been via email. Email is fast and it is not especially "pushy" in comparison to many alerting services. It suits us.

For our small group, the buddy system worked very well. All of us are at least partially retired, which gives us time to monitor 6 meters and react to pings from each other. There is also friendly competition among us regarding our successes, stations and operating styles. We are effectively egging each other on. The enthusiasm for our common pursuit rises from the positive feedback. At the BBQ we discussed the ways in which we can improve our results next year: remote operation, amplifiers and antennas.

During the exceptional 1989/1990 solar maximum, F-layer propagation frequently appeared, with shorter path DX continuing to be via sporadic E. I had just one local buddy with whom I kept in regular contact: Gord VE3KKL. F-layer propagation is more predictable but not enough to plan your operating schedule to the solar indices. 

Finding DX was also more difficult since there was no global DX spotting network and you had to spin the dial to find those CW and SSB stations. The scanning feature of VHF/UHF rigs came in very handy, provided you and your family could tolerate the constant hiss and occasional signal burst emanating from the radio shack. Gord's family tolerated it, but just barely.

The problem for me back then was my time. I was young, working full time and with a busy social calendar. The buddy system mostly went in one direction. Getting calls from Gord at work was aggravating since I could not get on the air, and I regrettably missed many openings and the possibility of new countries. Remote operation was out of the question. When I couldn't react to his alerts we could still share our passion for 6 meters by discussing openings, predicted openings, DX stations heard or rumoured to be active.

I am relating this story since I learned not long ago that Gord became a silent key earlier this year. We spoke less frequently in recent years. I was remiss in reestablishing contact with the many old friends during that 20 years of inactivity. But soon after I returned to 6 meters we bumped into each other on 6 meter SSB and later in person. However, like many, he didn't make the leap to digital. There was little left for him to work on the traditional modes.

We all need our DX buddies on 6 meters. Recruit them, celebrate milestones and remember them when they're gone.