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Windy weather at DD5LP QTH


#1

Just took a short video of how much the home station 40m loop antenna moves in the wind here. In fact the “solid” mast wasn’t doing too badly on the movement front either considering neither of these masts have a high wind resistance!

Ed.


#2

If that was my set up I would be biting my nails!

I looked at the weather charts and there is a nice little depression zipping across northern Germany, it should be in Ukraine by midnight!

Brian


#3

Wind is that it

now this is wind

80mph gales hitting me shed side ways rain proper like LOL

Karl


#4

Hello Ed,

The guy line arrangements are not very much in shot. At first glance your vertical needs 2x3 guys.

I cannot tell from the video how the mast is guyed but it is moving around too much and will eventually fail through fatigue if it is a ali tube.

Our house is on a hill and the SteppIR vertical has five guys and the SCAM mast has seven - that said the mast is never put up here if it is 30MPH plus. Today gusting here at 55MPH.

Cheers
Mike


#5

My shed two years ago prior to strapping it down in back of garden in hedge, strimmer still attached to walls and the M/C’s Untouched that was a rough winter 2013 :smile:

Karl now that what you call wind :smile:


#6

Hi Brian, Hi Mike,

The squidpoles that support the 40m loop are in the corners of my garden to get the size required - they cannot be guyed as that would require me running guys into the neighbours properties - not an option! The feed-point squid-pole has a guy which helps a little but only in one direction of course. These squid poles will flex without breaking and when the winds become too much, they drop down inside themselves reducing the height (an auto-safety feature if you like).

I am more concerned about the mast and rotator. it is clamped to the building at one side and strongly guyed on the other side, at about half way up. I bought a thrust bearing when I had my 2 ele mini tri-bander on the mast but the problem is that to get a third guying point for that, I would have to go over the roof and all attempts to get a rope over there failed.

If the winds get really bad (and that was not bad today), I can lower the mast down as I have it mounted on a tilting hinge.

The feed-point “squiddy” will have to come down tomorrow in any case as it appears through all the rocking about, it has a bad contact somewhere, as I am hearing signals breaking up and checking the SWR, it’s up to 3:1. I’ll check/tighten the guys on the Alu mast at the same time.

I don’t expect the mast to shear as it’s thick walled and double thickness in some places but the small rotator (a Yaesu G250) is most likely the weak point in the set-up.

Despite the antenna whipping around like that all day today, I managed to bag 5 contacts in the times I was in the shack - some appeared to vary a little in signal strength (not surprisingly with the loop whipping about).

Ed.

P.S. I was planning to put up my Snowdonia XR-80 vertical yesterday - glad I didn’t or there would be three poles whipping around in the same vicinity!


#7

Ed,

Windy, yes. I think that amount of movement is going to stress all your connections too much. What wind strength was it? How will it all behave in twice that amount of wind? I suspect breakages will occur then.

The squid poles can be stabilised without using extra ground space, by using a spreader about half or one third up. Run some guying ropes from the top back via the spreader, then to the base. It will stabilise it very effectively. A 3 way spreader is sufficient but 4 way might be easier to attach. Only need to be say 35-40cm long. Similar to how some flagpoles and ventilation pipes are guyed. You might be able to stabilise just in the direction that is not already stabilised by the antenna wires.

You can use the same technique on the rotating mast.

Even steel water pipe would be a more stable alternative. The fibreglass poles are flexible and lightweight by design but not ideal for more permanent installations.

hope this helps

73 Andrew VK1DA


#8

Hi Ed,
The bottom line is that they stayed up. Therefore your system is too small.

I am wondering what the two to antenna on your pole are. 2 element beams or horizontal loops?

73
Ron
VK3AFW


#9

Hi Andrew,
What exact winnd strength I don’t know - I’m guessing at about 80Km/h - and the system has been up in 120Km/h winds (and in fact the poles were higher then).

I like the idea of strengthening the poles using spreaders - I’ll look into that.

Ron, the antennas on the ali mast are Moxons (6m & 2m) plus a combined 2m/70cm omni-directional antenna used for listening to the ISS and general usage. So none of them are large.

73 Ed.