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yesfan
31-07-2009, 04:17 PM
Is there anything I can do to reduce the movement of a wall mounted dish when its windy? I currently have a 1m orbit dish mounted on a 5 ft pole held by T & K's. The dish is attached to a Motek SG2100.

In moderate wind, the dish moves considerably and makes the weaker channels unwatchable. Unfortunately, I do suffer from wind fairly frequently (no doctor jokes) where I live.

I am looking at changing dish/lnb/motor soon ready for the new footy season so any recommendations will be well received. Could probably go for a smaller better quality dish, better lnb or alternate positioner type?

Not many options as far as position on the wall, its currently in the only place that enables me to get the full arc. Cant floor mount because of trees.

Satcat
31-07-2009, 04:35 PM
You don't say what dia pole you have and what it is made of, Aluminium or steel. I would have thought that 2"dia steel should be solid enough at 5 foot

yesfan
31-07-2009, 05:04 PM
Its an aluminium pole, not sure of the diameter but it fits the standard dish brackets fairly snug. I've got a 6 foot scaffold pole lying around, thought that might be a bit heavy though? There's a good gap between the T & K's. Its a start though, will get a steel pole rather than ally.

Giga
31-07-2009, 05:06 PM
Is that pole flexing? replace pole with greater diameter and Wall Thickness (galvanised steel)
or is it the dish?

go for a stronger stable fix
http://www.yourtronic.nl/product_images/SAT-WMS30-2.JPG
1.5 meter pole? how much of the bottom part is fixed? increase the distance between the brackets.

dishsize: 3.28 ft 1.0 m

WindSpeed Wind Load
mph km/h lbs. kg
30 048.28 032 015
50 080.47 093 042
70 112.65 182 083
90 144.84 300 136
110 177.03 445 202
120 193.12 542 246

yesfan
31-07-2009, 06:09 PM
Thanks for the info.

http://www.yesfan.eu/pics/Dish.jpg

This is the current setup. The top K bracket could move up a bit, it does look a bit top heavy. Definitely would benefit from those brackets you recommend, although the movement does seem to be mostly from the dish itself. If I got a decent 80-90cm dish, would that pull in as good a signal?

Gone_Fishing
31-07-2009, 06:24 PM
Thanks for the info.

http://www.yesfan.eu/pics/Dish.jpg

This is the current setup. The top K bracket could move up a bit, it does look a bit top heavy. Definitely would benefit from those brackets you recommend, although the movement does seem to be mostly from the dish itself. If I got a decent 80-90cm dish, would that pull in as good a signal?

Not sure why people do this but look how much pole you have above your top bracket with your dish on the end

I have the same setup but I only have 8" above the top bracket which is all thats needed for the motor and about 16" between each bracket

8" at any diameter pole is never going to move/flex :king-042:


TNT

Giga
31-07-2009, 06:46 PM
corner brackets looks OK. As TNT mentioned, reduce the free part of the pole and get a heavier pole, yours is already bend! did you look at wind load? up to 1/4 Ton preasure!
mount for simular dish:
http://i654.photobucket.com/albums/uu270/Jan_Gruuthuse/poleTDS110.jpg

yesfan
31-07-2009, 08:51 PM
Hadnt noticed that before, there does seem to be a curve in the pole! The pole doesnt really need to be that long either? If I halved the length and spaced everything properly I could get away with cutting down the scaffold pole to 3-4 foot and use that, or would it still be too heavy? Time to dig out the grinder!

Giga
31-07-2009, 08:58 PM
2.5 inch in galvanized steel pole, wall thickness pole 0.15 inch

Gone_Fishing
31-07-2009, 09:07 PM
I use a scaffold pole :king-042:

But as I said before your problem is caused by having so much pole above the top bracket with the dish on the end

If you imagine a diving board that was only a foot long it wouldn't be much good make it longer and it becomes very springy same thing with your dish :respect-051:

I'll have my slide rule out in a minute :302:


TNT

satwyn
31-07-2009, 09:10 PM
Thanks for the info.

http://www.yesfan.eu/pics/Dish.jpg

This is the current setup. The top K bracket could move up a bit, it does look a bit top heavy. Definitely would benefit from those brackets you recommend, although the movement does seem to be mostly from the dish itself. If I got a decent 80-90cm dish, would that pull in as good a signal?I now use a 3 inch alloy pole this will be stable in very high wind conditions also consider shorter T/K brackets if possible also if you can place the dish motor between the brackets

yesfan
31-07-2009, 09:33 PM
Job for the weekend!

@TNT thanks, top bracket going up, might have to change motor though. Its been up there a few years and Cornwall suffers with salty wind (painful), if I put a spanner to it there wont be much left :001_07:

@satwyn, Not going to move much with the motor between the T & K's, didnt think of that, cheers for the advice.

@Giga, thanks for the pole and bracket recommendations

Ok, next thing. Would a smaller dish with top notch lnb perform as well or better than a larger dish with cheap lnb? What can I put on the motor bracket nuts and bolts to protect them? Think I initially covered them in mastic, didnt work too well. Or should I just buy new bolts if required?

philips
01-08-2009, 03:57 PM
My understanding is that a small dish only produces a small signal and a "good" LNB cannot overcome this. A larger dish produces a better signal and the LNB is therefore not so critical.

From a practical point of view, if you have to change anything to improve performance it's easier to change the LNB than the dish!

AJR
01-08-2009, 04:15 PM
What can I put on the motor bracket nuts and bolts to protect them?

Self amalgamating tape works a treat.

yesfan
01-08-2009, 06:13 PM
Had the mastic in one hand and the amalgamating tape in the other, had just used the tape to protect the cable connectors but still chose the mastic for the mounting nuts? doh!

Cheers AJR

wod
02-08-2009, 12:14 PM
what i would do is replace the pole with a length of scaffold pole and put a t bracket just below where the motor bolts to the pole this will help stop it moving about

or you could buy another set of brackets and use 2 k brackets with a t bracket in the middle and still have the dish mounted above the brackets

AJR
02-08-2009, 12:20 PM
I think that the better way (as mentioned above) and the cheapest.. is to mount the motor between the existing brackets and just cut off the wonky top end of the pole, use a new pole or not.. providing its vertical, the existing will be fine.


but still chose the mastic

I really hate mastic... it gets on your hands and spanners, wipe your hand across your forehead and its there as well, put your spanners in your pocket and mastic lined pockets, the worst is when you hold the spanner in your mouth :puke:

harrydocuk
02-08-2009, 12:43 PM
copper grease in a spray can for your bolts and threads yesfan.

Gone_Fishing
02-08-2009, 02:02 PM
Anything will be better than it is now, top bracket is in the middle of the pole dish at the unfixed end that means its acting like a big lever on the bottom bracket :)

The shorter the pole the stronger it gets and the same with the distance between brackets, that pole is perfectly adequate just not as things are now