PDA

View Full Version : Mesh dish



todray1
29-12-2013, 09:33 PM
Hi all

Looking for advice.
Due to the open costal area that I live. We seem to a get very strong winds and the damage that comes with it. I have Triax 1m dish and the strong
winds before Christmas blew the dish passed the motor stop point. When I tried to reset the dish there was just to much play in the motor when I set on a satelitte;
and required a new motor. My question is are the mesh dishes any good, thinking of a Gilbertini 80mm. Any help and advice would very helpfull

geoffh
29-12-2013, 10:25 PM
Hi, I have allways been advised that solid is better than mesh for any given size wrt signal strength (although never proved it).
I use a Triax 78cm dish in an elevated and exposed position, south facing, 450 feet above sea level and at a high point locally, its wall mounted and driven by a technomate motor. The dish and motor have been there for 6 years and taken everything thrown at it including the recent storms. Not sure whether a 1m dish would have survived though, anyway her indoors won't allow it.
It gets all the birds I want except for the desired transponders on Nilesat

todray1
30-12-2013, 09:54 AM
Hi, I have allways been advised that solid is better than mesh for any given size wrt signal strength (although never proved it).
I use a Triax 78cm dish in an elevated and exposed position, south facing, 450 feet above sea level and at a high point locally, its wall mounted and driven by a technomate motor. The dish and motor have been there for 6 years and taken everything thrown at it including the recent storms. Not sure whether a 1m dish would have survived though, anyway her indoors won't allow it.
It gets all the birds I want except for the desired transponders on Nilesat

Thank you Geofth
You have given me something to think about. Will let you know what I decide.
Looks like more heavy rain & strong winds again this week, at this rate could be 2015 before I try. lol

grafter
30-12-2013, 05:22 PM
A mesh designed for Ku will show little difference in performance compared to a solid. I've got an unbranded 85cm mesh which works very well and isn't far down on the 1m Gibertini I replaced it with! For comparable sizes there's little if any difference in wind loading as wind won't pass through the mesh. The only benefit is reduced weight but I'm not sure that really matters for 1m dishes, most diseqc motors should be able to handle that load without a problem.

Detlef
30-12-2013, 05:54 PM
Also a mesh dish will react to the wind in much the same way as a solid dish. The reduction in aerodynamic "drag" will be small and hardly noticeable. Mesh dishes are slightly better during very wet weather as some rain will pass through the holes but again I doubt if you will notice it.

With regard to signal performance, the hole size is chosen such that the Ku band radio waves see it as solid.

dypcdiver
30-12-2013, 07:30 PM
Slightly off subject, but I have a mesh dish mounted in Andorra (at 1860m) and find that a downside is that the snow sticks to the mesh and I lose the signal. My next door neighbour has a solid dish and does not suffer the same problem.

ABA
30-12-2013, 08:23 PM
the main mistake people make when fitting dishes providing you have a clear line of sight from dish to satellite they will work just as well on the ground as say on a10 story high building hight dont matter

Detlef
31-12-2013, 02:30 AM
Offset dishes also work when laid on their backs. Only useful if you have a stroppy landlord and you want to disguise the dish as a patio table.

malsat
31-12-2013, 01:09 PM
Offset dishes also work when laid on their backs. Only useful if you have a stroppy landlord and you want to disguise the dish as a patio table.

"laid on its back" how ?

Detlef
31-12-2013, 02:56 PM
Like this (guess who only got an "D" for art?):

BTW you need a mesh dish or you will only have a useless birdbath :D

digicon
31-12-2013, 04:03 PM
Offset also work Upside down as well if you feel the urge :-)

cosworth4x4
31-12-2013, 05:10 PM
Like this (guess who only got an "E" for art?):

BTW you need a mesh dish or you will only have a useless birdbath :D

it looked a good drawing until i opened it ,:biggrinjester: .

but it did the job and explained the point ,:respect-048:

Bbigfoot
31-12-2013, 06:28 PM
Hi All,

@todray1, As long as your not
interested in (7w or 26e) an
80cm mesh dish will pick up all
the Sats we can open.

Not wanting the dish to stand
out as a motorised setup I ordered
a S@y zone 2 60cm mesh dish
and a motor. (Dish had S@y LNB)
Needed to adapt the two U bolts
that came with the Dish (too Small).
Picked up two car exhaust U bolts
from Gearbox. That sorted it.

Thing is my 80cm solid dish
pulls in 80% Sig quality on
a S@y channel, 28e (99% on BBC 1)
the 60cm S@y mesh dish
pulls in 92% Sig Quality.
It does the same on 30w Hispasat
the 60cm dish has the strongest Signal.

BF.

Detlef
05-01-2014, 01:49 AM
Interesting!

It sounds as though the 60cm dish is better set up (skew, focus, etc) or the LNB is better.

Another possibility is that the 80cm has an LNB that is not fully suited to it.

geoffh
05-01-2014, 10:36 AM
A mesh designed for Ku will show little difference in performance compared to a solid. I've got an unbranded 85cm mesh which works very well and isn't far down on the 1m Gibertini I replaced it with! For comparable sizes there's little if any difference in wind loading as wind won't pass through the mesh. The only benefit is reduced weight but I'm not sure that really matters for 1m dishes, most diseqc motors should be able to handle that load without a problem.

Hi Grafter
Can you get the jsc/bein channels on 7 west with your set up and what part of the uk are you? I might just get this past the Mrs if I can get those channels. I'm in the cotswolds.
cheers
Wondered if this might do the trick

ISS 90cm Mesh Steel Dish, Pole Mounted
- Reflector dimensions (cm): 88 x 83
- Dish Material: Galvanised Steel
- Thickness (mm): 0.7
- Surface treatment: Epoxy-Polyester Powder coat
- Mounting: Pole Universal
- Mounting material: Hot-galvanised steel
- LNB clamp size (mm): 40
- Elevation (degrees): 5-57
- Efficiency (%): 80
- f/d Ratio: 0.65
- Cross polarization: >27.0
- Gain (dBi): 38.2-39.7

Bbigfoot
05-01-2014, 10:20 PM
Hi detlef,

The 80cm dish has had
Invacom LNBs, and others
over the 10 years.
It pulls in 99% and 100%
on Channel 4 and other non
S@Y channels,
but only around 84% on any
S@Y Channel, both dishes
LNBs have the same
scew (5% west @ 55% North).

The only thing I can think of
for the S@Y zone 2 60cm dish
pulling in !00% on (Most)
S@y channels is the dish
is an Elliptical mesh Dish.

BF.