Thanks, Eliakim

Morning antenna maintenance involved an N95 particulate mask, gloves, and goggles today.

I arrived back in Madagascar late in the evening last week after a brief vacation in Réunion. The next morning, I fired up the rig to see what was going on in the CQ WW WPX SSB contest and rotated the hexbeam towards Japan. The rotor control showed movement through about the first ten degrees, and then it froze. I backed off, tried jiggering it back and forth a bit, thinking that perhaps it was just sticking, but gave up after a few seconds because I didn’t want to strain the motor. I walked out back…

… And it was clear why the antenna wasn’t rotating, about a meter and half below the base of the hex beam, the mast had a kink of about 20 degrees, and the hexbeam was lopsided, brushing against a nearby tree. After surviving four cyclone seasons, it appears that the last one of this season, Eliakim, took its toll.

Cyclone Eliakim’s Swath

When I had left for Réunion, the storm was forming to the east of Madagascar and it was predicted to track southward off the coast of Madagascar. This was somewhat bad news on the vacation front, as it meant that we would also have a lot of rain in Réunion.

Storm track for Cyclone Eliakim. The station is located in Antanarivo.

In fact, the night we arrived in Réunion, the island was hit with torrential rain and the rental car agency warned us to be extra careful with the night drive down the west coast. As far as we were concerned, this was overly cautious — roads in Réunion were first rate in terms of construction and people there seemed to obey traffic laws, so what was the worry? As I approached the highway, I noted that a traffic sign stated road conditions as “houleuse”, a word which I had always associated with rough seas and I wasn’t sure how it applied to the road — until a twenty foot wave crashed over and across four lanes of the highway. Later, I learned that the highway runs right along the sea.

It looks worse from space.

Damage Survey

Anyhow, despite lower wind velocity and a track which did not take this cyclone down the center of Madagascar, as others had, I had not lowered the antenna in preparation for this cyclone, and perhaps due to cumulative stress, the Spiderbeam Heavy Duty 10m mast buckled above the upper of the two guying rings. I can’t say that I’m unhappy with the performance of this mast — it survived three and half seasons under harsh conditions. My plan is to just replace the bent section, as the rest of the mast is fine.

The bent section of mast.

Right now, we don’t have a firm date to depart Madagascar, but it will likely be in the summer of 2018. Consequently, I had planned to start winding down the antenna farm over the next few months, but this event forced my hand.

Bringing The Hexbeam Down

With the help of some friends, I lowered the antenna, which telescoped down without a problem up to the segment that had bent. After removing all the guying, I lifted the top section and walked it down a ladder. I was able to detach the antenna plate from the mast and carry the antenna to a table in the yard, where I went about removing all the wiring and support cords, allowing it to flatten out. Luckily, my backyard is just large enough to accommodate this.

The mast base (left), dismounted hex beam (center), and a corner of a satellite dish (right).

After almost four years in the tropical sun, the antenna had gotten hairy. As expected, the fiber glass got rough thanks to UV exposure and since I knew that rubbing up against it would make me itchy, I came prepared with long sleeves and gloves. For sanding it down, I also added goggles and an N95 particulate surgical mask. It took a few hours, but eventually, the support arms were smooth, and I was able to apply an oil-based paint, which should make the support arms more resilient to future sun exposure. of course, I opted for “Juliano blue”.

Halfway painted.

While painting, I left all of the o-rings in place, which I hope will make it fast next time to wire up the antenna, without moving them around. The segments might not pack up quite as efficiently, but I can live with that.

As for the mast, I had no problem removing the rest of it from the thrust bearing and rotor. The support beam now looks naked without the shelves that supported all this equipment, and I probably will not put anything else on it while I am here. Prior to moving, the support beam itself will have to come out, which will involve pristine technique and a sledgehammer.

Next Steps

I still have a few HF antennas up: the vertical for 30m and the full wavelength loop for 40m, but both are very noisy. I am considering converting the 30m to as big an inverted L as space will allow, sticking an antenna tuner right at the base, and seeing what it will tune. The base of that antenna is just above my roof, and I have run elevated ground wires to the razor wire fence that runs around the property. I won’t even attempt to model this.

I haven’t spent really any time running low-signal modes, so considering the antenna situation and time left here, I think I will focus on running FT8, particularly on lower bands.

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