I thought my greatest problems at the moment were the holes made in the drive by a marauding hedgehog. I even have pictures of him/her (can there be two of them?) wrecking the place thanks to an infra-red trail camera. They are entitled to be here, but can they not use the drive to pass along rather than dig it up?
No, things got worse when my main mast suddenly started to give problems. The main mast is a CUG 12m three part square section mast, with my 6m, 4m, 2m and 70cm antennas on top. I will no doubt give more details on the antennas later, but for now it is the mast itself that took all my attention. The mast is raised and lowered using a lead-acid battery powered winch. I recently replaced the winch and the wiring and then fixed up the original winch as a spare.
First problem was that it started to go up and down slowly. Having replaced the winch I thought that it was unlikely to be the problem. Then it would only go up twice before the battery needed to be recharged while before it would go up and down eight or ten times between charges. Although the battery appeared flat and it would not raise the mast, the smart charger declared that it was 100% charged. Most odd.
Then it blew a 25 amp fuse. I had increased the fuse from 20 amps to 25 amps during the re-wiring because the previous one had got scorched but it had not blown. It seemed unlikely to me that the 25 amp fuse would blow under normal circumstances.
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| GM4FVM fault finding with his mast and almost new winch (photo Mrs FVM) |
Clearly something was adding a heavy load to the winch. I would have to investigate further.
I then recalled an occasion 10 days before when I had tried to lower the mast on a windy evening. The middle section of the mast had jammed about 30cm before the bottom. This was due to the wind pushing the mast aside in the bottom tube and it then caught on a piece of poor galvanising and stuck. There are a couple of bits of poor galvanising on the mast and this has caused trouble before. Perhaps this was the cause of the current problem.
As in all good scary TV police reality shows (isn't "24 Hours in Police Custody" the best of these??) I had to go and seek CCTV images to find the culprit. Luckily the Anti-Hedgehog Trail Camera (AHTC) recorded the whole event on 4 June 2026 starting at 21:25.34 when the temperature was 11C (flaming June weather in IO85) and the sound track proved it was windy. Ah ha! Evidence. PC Dixon has found the culprit - me. Well, actually a combination of the construction of the mast and the wind - and me.
I had trouble lowering the mast fully that night ten days before. When I tried to lower it the middle section stuck and the cable lowering the upper section (which confusingly is on the middle section) fell slack. Now I was worried at the time that when the slack middle section cable eventually tightened up it would not fall back fully on the pulley, so I reckoned I had better get the thing down properly.
By repeatedly raising the mast a small amount, about 50cm in total, and lowering it again I kept returning to the point at which it was sticking on the way down. I only did small movements to prevent the slack cable from failing to seat back on the pulley. Eventually a slight drop in the wind allowed the middle section to drop past the sticking point and it was fully down.
What I had not noticed in the dark evening was that the very thing I had been trying to avoid had happened. When the middle section cable had tightened up again it had fallen down the side of the pulley. This meant that the cable on the middle section was turning round directly into the inside of the mast rather than going smoothly over the pulley. This increased the resistance, added strain on the winch and was potentially going to lead to the cable wearing and breaking.
It was hard to see this from the ground, but up close the problem was obvious:-
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| Cable down side of pulley |
The danger of this wearing down strands of the cable to the point where it snapped was sufficient to get me to fix this right away. I happen to know that I started to fix it on 15 June 2026 at 09:32:10 and when the temperature was 15C. This is from intelligence gathered by the hedgehog detection system.
I knew that all I had to do was to generate some slack in the cable and then pull it over the pulley. To do this all that was needed was to push the middle section of mast into the bottom section while holding the top section fixed to the middle. Impossible in my current ancient weedy state as I do not have the strength left to push the mast in while it is lying on its side with rotator and antennas on top. Simple, just fix the upper section steady and tilt the mast vertical when it will fall back together under gravity and the cable will go slack. That is how it went slack in the first place. Well, maybe.
I had got confused because it was the upper section that I needed to fix in place whereas I tried to fix the middle section. I did this by wedging two large heavy screwdrivers into the gap between the sections and turning the mast vertical. So I wedged the middle section rather than the top one, but it worked and at least I had proof of method for getting them in the right place next time.
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| Two old heavy screwdrivers in the wrong place, but the idea works |
While I had the mast vertical I momentarily pressed the "In" button on the winch control rocker switch rather than the "out" one. It only moved a fraction, but that was enough to release both screwdrivers from a height. They clattered down the back of the mast, hitting the mast brackets before scattering. One has never been seen since. I have no idea where it went. What could I do, apart from sending Mrs FVM to look for it and she has not reported back since. It a big thing but it is lost. This just shows that a hard hat is needed for working on antennas as a large screwdriver falling from a height could do a lot of damage to the head.
Luckily it turned out that one screwdriver was enough to hold the top section up and everything worked out fine. The cable is now happily seated on the pulley and everything runs smoothly.
Next snag is that the mast jammed briefly at the same point last night during windy conditions. This time the cable did not lift, but it could have. I must get round to filing down the uneven galvanisation at the point where it jams.
Things to note:-
Beware slack cables on masts
Beware falling screwdrivers
Beware large screwdrivers disappearing into thin air
Beware hedgehogs vandalising your drive.
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| Hedgehog attacking GM4FVM drive around 00:20 local time |
In fact, just be careful.
73 Jim
GM4FVM
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