ChrisW
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| posted on 29/4/15 at 03:55 PM |
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Need more aerial height
I know there are a few radio HAMs on here, but this is also a general engineering question so interested to hear everyone's thoughts.
Here's my current setup: http://chrisw.net/pics/img_4447.jpg
The pole is a 2" x 20ft aluminium, I believe 'normal' 16 gauge. Approx 1/3rd (ie 6ft) is between the T and K which, in hindsight,
is probably too much. Up top is a Diamond X50N vertical colinear and a little lower is a Ubiquiti AirGrid AG-HP-5G27.
(http://dl.ubnt.com/datasheets/airgridm/agmhp_datasheet_web.pdf).
Unfortunately the land rises up at the end of the garden and a new house has been built and it's now blocking the LoS for the AirGrid ie I need
to get it higher to see over the new roof. My mate is bringing his laser level thing round later to get an idea of how much higher, but I reckon 3m
to be safe.
However my plan is to add a 'heavy duty' pole at the base and then use 'scaffolding brackets' to couple my existing mast on
the top.
eBay Item
^^ brackets. They swivel, hopefully that will make it easier to put up. I'll probably switch the nuts for nyloc types just in case.
Pole at alltrade: http://www.alltrade.co.uk/mounting/masts-aluminium/0297
Not sure if 0.25" wall thickness is correct, that sounds mega thick to me (6.3mm). It might be stupidly expensive too, but they have a 14 gauge
one too (http://www.alltrade.co.uk/mounting/masts-aluminium/0283). I'll saw it down so I gain about 2.5m and then move the AirGrid up a bit on
the pole.
Anyone care to give any comments/advice? Am I pushing my luck too far going up that high?
Cheers, Chris
My gaff my rules
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HowardB
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| posted on 29/4/15 at 04:06 PM |
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Chris,
I have seen some amazing pole arrangements, if you were to use a standard aluminium scaffold pole at 5m long it will be very heavy, it is also 1 29/32
od so will only match with another scaffold pole. Unless it is very windy there, then it is probably overkill for what you are trying to do.
I would suggest the use of 2" 5m, with a 1 1/2" slid about 4' inside with concentric spacers and pinned in place, that would give
considerable extra height, minimum weight if it were all 16g wall thickness, and low wind loading.
good luck
Howard
Howard
Fisher Fury was 2000 Zetec - now a 1600 (it Lives again  and goes zoom)
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ChrisW
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| posted on 29/4/15 at 04:23 PM |
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quote:
Originally posted by HowardB
if you were to use a standard aluminium scaffold pole at 5m long it will be very heavy,
Do you mean aluminium scaffold pole? I thought all 'real' scaffolding poles were steel!
quote:
Originally posted by HowardB
I would suggest the use of 2" 5m, with a 1 1/2" slid about 4' inside with concentric spacers and pinned in place, that would give
considerable extra height, minimum weight if it were all 16g wall thickness, and low wind loading.
That's an interesting ideal actually, assuming I could find someone to knock up some spacers for me. Simple job for someone with a lathe I
guess.
Not sure if it's possible to get 1.5" x 20ft though.
Chris
My gaff my rules
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HowardB
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| posted on 29/4/15 at 06:18 PM |
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Hi Chris,
As I understand it all new scaf poles are steel, I have several Ali ones though. Your local aalco or smiths metals will stock the tubes, probably
not cheap new but depends upon how important the 10' is. For the smaller dia you could try TV aerial pole. The aerials you have offer low wind
loading.
HTC
[Edited on 29/4/15 by HowardB]
Howard
Fisher Fury was 2000 Zetec - now a 1600 (it Lives again and goes zoom)
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