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 Advice please regarding Roof mounted hf antenna 
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Post Advice please regarding Roof mounted hf antenna
After 12 years of being on my chimney the SRC HF360 vertical antenna has snapped at the base during these storms!

I would have liked to do a straight swap but looking at the new version made by 'euro-com' I am not convinced this is the best option for my circumstances.
I chose this antenna out of practicality and not because I could not build something else .Being mounted at sixty feet in the air with no easy roof access a fibre glass monopole seemed to fit the bill and too its credit has survived for 12 years during several storms .
Alas nothing lasts forever .
I would be grateful for any advice from the membership regarding its replacement bearing in mind that I cannot easily access the roof and it would need to be something that will survive storms ,does not have small parts that can fall off or be blown away by high winds ,that works reasonably well from 80-10 metres and is lightweight ..........Any advice regarding would be good

Thank you in advance Adrian


Sun Feb 09, 2020 11:47 am
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 Advice please regarding Roof mounted hf antenna 
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Post Re: Advice please regarding Roof mounted hf antenna
Theirs nothing worth having 80-10 Adrian, why not stick a antron 99 up there and work on a loaded wire for 80/40.
Or a loaded inverted L?

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Sun Feb 09, 2020 11:52 am
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I agree, if you have space.

I use a modified iMax2000 for 15 12 and 10, and an end fed long wire for 160 - 17, and nothing has done better.

I would be hesitant to put my recommendation behind any modern offering in such a difficult to access location.

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Sun Feb 09, 2020 12:04 pm
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 Advice please regarding Roof mounted hf antenna 
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M0VMT wrote:
Theirs nothing worth having 80-10 Adrian, why not stick a antron 99 up there and work on a loaded wire for 80/40.
Or a loaded inverted L?


:good: Good advice Mark thanks, As usual this forum is the best place to ask these questions

I still have an antron somewhere in the attic. I would add an air wound choke to the base

I could clamp and tie wire to its mounting pole for the inverted L but the wire would need to follow the roof contour for safety so perhaps I could add some wire stand offs along the roof ridge ?

With the occasion of getting up there I could really come up with something more fruitful that would better match my circumstances. I should see this as an opportunity rather than a setback


Sun Feb 09, 2020 12:13 pm
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 Advice please regarding Roof mounted hf antenna 
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Sangoma wrote:
I agree, if you have space.

I use a modified iMax2000 for 15 12 and 10, and an end fed long wire for 160 - 17, and nothing has done better.

I would be hesitant to put my recommendation behind any modern offering in such a difficult to access location.


I also thought that too Steve, the fibreglass antenna did survive all those years but as you rightly point out the more modern offerings might not be as suitable ...Build quality is a concern


Sun Feb 09, 2020 12:23 pm
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Post Re: Advice please regarding Roof mounted hf antenna
I don't know if you noticed the end of my inverted L running over the roof with the end tied about 12' off the ground, but when I had it tied off vertically down it seemed to work as well.
It runs over the ridge tiles and moves around, I'm using field telephone wire, which was not showing any signs of damage after a few years.

The other end is tied to the fence and fed with 9:1 unun, then up a 10m fishing pole and from there to the roof.

If you could get the feed end on a fence, then to the roof, it should work quite well.

The imax2000 is fibre-glass, but it flexes a lot in the wind. I can get mine down with a step ladder, so very different to yours if it goes wrong.

Is the place on the roof where it is mounted accessible for a pulley?

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Sun Feb 09, 2020 12:52 pm
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 Advice please regarding Roof mounted hf antenna 
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I could put a pulley mechanism on the chimney Steve but it would not be accessible if something went wrong with it so I think perhaps a fixed wire would be better . The old antenna has now broke away completely but fortunately is wedged against a neighbours wall so cannot do any damage.


Sun Feb 09, 2020 12:57 pm
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Looks like you have tried something similar before :)

Fishing pole in the back corner by the mini-factories like you had, then over the roof and down to the front garden, with the feed at the bottom of the fishing pole. That would just about give you the length you need, and if you needed a bit extra, stick it to the of the low side wall in front.

You don't even need to get above standing on the ground to do it.

It is not as good on 15 12 and 10 as it is on the lower frequencies, bt for space and flexibility, it is the best I have found in a small space.

Using thin wire, it is barely visible, try to persuade the manager to let you try it, with the promise that you will take it down if she considers it an eyesore :)

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Sun Feb 09, 2020 2:45 pm
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Comrod AT100D, the only way it’ll sustain damage is if the buildings surrounding it collapse, I can’t recommend it highly enough.
Sell a kidney. :D


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Sun Feb 09, 2020 3:40 pm
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 Advice please regarding Roof mounted hf antenna 
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:) Yep I have tried this Steve but I just cant get the height . My garden is only 3.6 metres wide (12') because that is the overall width of my house the wire would then need to be lower than the roof ridge above an upstairs window otherwise it will get tangled with a quad I have at the back of the house . However because I will need to get on the roof anyway I could put a nylon stand off at that point to then follow the apex of the roof up to the chimney and do as you suggest I will try to provide a diagram or some photographs but I think you get the gist of it .

There is much that can be done even with a very poor location for radio


Sun Feb 09, 2020 7:22 pm
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ei9ju wrote:
Comrod AT100D, the only way it’ll sustain damage is if the buildings surrounding it collapse, I can’t recommend it highly enough.
Sell a kidney. :D



WOW! If it is marine stuff I know what you mean . Just add the word 'marine' and the price can double.

I used a 10 metre long fishing pole last year in the back garden with great results .Once I had it mounted on my garden wall as a support I had 45 ' of wire

Trouble is some telescopic poles are only suitable for temporary installations and unless it is tied off or guyed they can whip about somewhat.


Sun Feb 09, 2020 7:32 pm
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Post Re: Advice please regarding Roof mounted hf antenna
I use a 12m pole with the top two sections removed, it does flex, but not too bad.

Noted on the quad, that does make it more difficult.

What about putting a pulley on a short mast where you present vertical is, and running the loop down the back of the house?
It could be long, so that when pulling it up or down you could walk back so that it doesn't go over the gutter at too much of an angle, and when it was all tied off on a cleat on the wall, it wouldn't be very noticeable.

Allowing for a bit of flex in the pole, you would get 9m vertical, 10m to the pole on the chimney, leaving 7-8 metres from the pole down the front of the house, won't even reach the ground.
Another small plastic cleat on the front of the house, it will be far less noticeable than a telephone wire.

Only thing I would say is to use a decent stainless yacht puller, and some decent UV proof yacht cord for the line, and it will be good for many years.

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Mon Feb 10, 2020 6:20 am
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 Advice please regarding Roof mounted hf antenna 
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Post Re: Advice please regarding Roof mounted hf antenna
;) Thanks for that Steve . I have a number of Items that might work well with this set up
I have an old Antron A99 in the attic that I could use on 10/12 metres(as suggested by Mark) if I put it onto the existing stub mast and chimney cradle
This will cost me nothing .From the stub mast I will bolt a pulley. I have a decent one that I picked up at a rally . I have a reel of cable stranded copper which might be more than suitable for the purpose . I will need a stand off (nylon rod 66 25mm) which I will attach with k & T brackets just underneath the guttering ( I have this stuff too ). This height should not get tangled in my quad the vertical piece in the garden I can use a 6 meter fishing pole as a support . I have two of these in the attic . That should give me about 16 metres of wire in an inverted L .
I have a 9:1 unun that I made myself and All being well if I attach this to the earth mat that I put underneath my patio this should give me a reasonably good set up .

The only real difficulty now is getting on the roof and waiting for some decent weather to sort it out .

I will keep you updated on my progress

Many thanks Adrian


Wed Feb 12, 2020 9:13 pm
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