Installing Multi LNB dish

[satworld98]

I am planning on installing a Triax 90cm dish (or Gibertini 85cm) with multi LNB (4). I am wondering if you guys can give me an idiots guide. I was going to use the Torodial T90 but I have been discouraged plus I am not very minded towards motorised system (I want instant switching plus what it will be easy for my misses to use)

Including the following:

1. Does the elevation of the dish remain the same regardless of whether it is pointing to 28.2E or 19.2E or indeed 28.2E, 19.2E, 16E and 13E (I will be using Alps Twin)
2. Is skew the same as polarization ? if it is do i just adjust it by bending the LNB holder?
3. Skew I quess is the left/right (west/east)?
4. Tips on either of this two dish. i am still not sure which is better gibertini or Triax
5. Pls do iclude general tips on how to install. I have never done any but I have picked up quite a bit on this forum and other sites.

Thanks in advance for your help

 

[rolfw]

The Triax with the four LNB holder is good (nothing wrong with the Gilbertini either.), you set up the dish on the central satellite, so the elevation is set for that, the offset arms then either bend upwards or downwards, depending on the slope of the arc. Skew is the amount of rotation in the holder of the LNB, to correspond with the orientaion of the satellite in relation to your longitude.

 

[satworld98]

thanks as usual rolfw. you have benn very helpful and i must say i have picked up your brain on many issues already on the archive post.

which one will you recommend to be the centre dish. 19E or 16E ?

my quess is 16E as I think it will be weaker . Am i right ?

since you are mr satellite !!!! lol if you are to pick one for yourself btw Triax or gibertini. which one will you pick? also do you think I should go for 100cm dish? I read from one of your post that the 1mtr dish is now allowed without planning permission?

 

[rolfw]

19 and 16 for the two centred LNBs, 16 is certainly the weakest as you say. .

 

[satworld98]

cheers. i will set elevation for 16E then.

i know 100cm gives you more than 90cm. will it be better for multifeed as well or shld i just stay on 90cm? (i think i read in one of your post that 80cm is better for multi LN

 

[rolfw]

1m would be better, it is only monobloc LNBs which are supposedly better suited to 80cm dishes and that is debatable.

 

[gerryb]

I posted my account of setting up Triax 1,1m ,in another forum .I will send you the link as a lot of it will not apply to you.Basically using the triax multibracket centered on 16o i got 7o,13o 16o 19o and 28o.I found that the bracket wasn't long enough for 28o so a bit had to be aded on.Also i found that the elevation didn't match what it theoretically should have been.You have to tilt the bracket high for 28o but may find it then too low for 7o! It will work but very time consuming.

 

[satworld98]

thanks guys. i will appreciate if you send the link. i am thinking of 5E instead of seven. i might actually leave 16E for 5E because os sports.

 

[satworld98]

will 5E be easy to get ? I mean 28E, 19E, 13E and 5E or will that be pushing it ? Any body who knows a good installer in luton area (bedfordshire) should let me know. I am thinking i should not do the installation myself. Also for people who had experience of this kind of setup. do I have to use narrow feed LNB for 19E, 16E and 13E or can I get away with normal LNB for all apart from the 13E?

 

[Jeff_19341]

@ gerryb

Think about it logically, for reception of off bore-sight satellites. Angle of incidence = angle of reflection.
Signal from 28*east comes in at a lower angle from the left (east if you are behind the dish) and is reflected by the dish. The LNB must therefore be to the right and higher to receive the signal. Vice versa for the signal from 7*east. Basic physics m8, hope that this has helped.

 

[gerryb]

If you are going for 13o 16o and 19o you will definitely need one narrow lnb for 13o or you wont get the other lnbs close enough.i happened to have a narrower Inverta (not as narrow as Alps) and it worked fine.All other lnbs are normal size.

 

[elr]

I would like to install a 90cm dish with 3 LNB for 4 degrees west, 1 degrees west and 5 degrees east. I am wondering if somebody can give me assistance since the distance between the center sat, 1w, to 4w is 3 degrees only.
Pls do include general tips on how to install. I have never done any but I have picked up quite a bit on this forum and other sites