Thursday, 10 December 2015

Wind, not vertical antennas and 6m activity

It has certainly been windy over the past few days.

If you needed any evidence of climate change, you just had to spend a week on the English/Scottish borders.

Last weekend there was a 36 hour period when we were constantly battered by high winds, with gusts up to 120km/h (known as Storm Desmond!). Then overnight last night (nameless!) we had some more, at higher strength.

Fortunately, although it rained a lot, this part of the Borders did not have the severe flooding which occurred on the West Coast and in Carlisle in particular. I could have been worse here, and I am grateful that we got off so lightly.

The wind does cause disruption. Last night the road visible from the shack window (the "A1" trunk road from Edinburgh to London) was closed after several HGVs (semi-trailers and their tractor trucks) were blown off the road round the headland at Burnmouth. In other words, within two miles of here.

Today the railway is plagued with blown down trees and branches. The line was closed for a while but now it has got a bit easier:-
Description
An object caught on the overhead electric wires between Berwick-upon-Tweed and Alnmouth is causing delays of up to 60 minutes to trains between Edinburgh and Newcastle. This is expected to continue until approximately 11:00.
Back here at GM4FVM the immediate effect of high wind is that I do not raise the Tennamast at all, or only to a limited extent. That protects the antennas and reduces the noise, but it limits what I can do on the radio. On the other hand, the 6m antenna and the 4m vertical are on T and K brackets and cannot be wound down, so they stay in the full force of the blast. The idea is that a simple HB9CV does not catch much wind, and the vertical should be able to stand it.


After all that wind, the 4m vertical is slightly off vertical. The 6m HB9CV looks to be in fine form, and you can just see the 40m dipole passing, and all those stood the wind OK.

The support for the 40m dipole has the 2m vertical on it, but it is lower down and guyed. I am pondering whether to put up a bigger 2m antenna and raise the 40m dipole, but not in this windy weather.

OK, it isn't a big lean. A few degrees. I do not have much to complain about. This place was not flooded, and my car has not been blown over (yet). But I am going to have to go up there and fix that.

This is the second time this has happened, as the antenna which was there before the present 5-8th, a Sirio J-pole, also got the bends. I just have to face it that the wind coming off the moors from the South West can bend just about anything.

Just to prove that the Diamond HB9CV is working on  6m, I went on during last nights wind and worked DF6HT on meteor scatter. As I cannot tilt or lower that antenna, I might as well use it in the winds.

That was a good contact for me (939km). Meteor scatter has been poor from here over the past few weeks (and months). With the Geminids meteor shower due over the next few days I am hoping for better results soon.

What can I call my 4m FM antenna now? It cannot call it a "vertical". It is a bit more bent than the photo shows (I could not get to the right angle to photograph it).

"5/8th wave not quite vertical 70MHz antenna"?

73

Jim

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