dish arm sizes - standard?

S

Sergei

Member
Messages
2
Likes
0
My Satellite Setup
none
My Location
Glasgow, UK
#1
I am looking to fit 2 or may be 3 LNBs to my unknown make 85 cm dish.

Currently there is one sitting on the end of the arm which is rectangular if cut across. I am getting Hotbird with strong signal in Glasgow.

There are many LNB multi brackets - for example
http://www.satellitesuperstore.com/multisat.htm -
a)universl Lenson 6 degree bracket
b)Triax 20 degree Multi Bracket which I may want to go for as I may get Astra too.

I need to figure out:

1)what arm sizes these would fit? I mean what height/width of a rectangular arm these are designed for? Is there a standard by any chance?
Basically what would fit my dish... Any links with dimensions/specs, please?

2) I need 8 degrees (Hotbird+sirius). Are 6 degrees brackets generally designed to be moved slightly wider if required?

3)As I have an unknown make dish (off-center LNB position-not prime focus) - would multi-LNB setup work with any dish? I mean some people say that (some) Tiax's dishes actually designed for multi LNB and they are not actually parabolical?

Ta very much
Sergei.
 
S

steffo78

Regular Member
Messages
71
Likes
0
My Satellite Setup
28E 19E on 120cm Gibertini homemade sidemount with Gibertini feedhorn, Inverto C120. 5E 1W on 85cm triax. Digiality VC-CI 204 and Triax dvb-65s receivers. Matrix-cam not working. Swedish Canaldigital "local", Norwegian Viasat.
My Location
Sweden/Norway,Telemark
#2
If you post a mpictuer of the dish someone might recognise it.

there are a lot of different solutions to the feed.
Universal mounts work but not optimized for your dish.
If you have tools you can make your own feed with a piece of metal and 2 clamps. I had 19E and 5E on a selfmade feed before. With a little tweaking this is no problem. I guess you should keep lnb for 5E in focus as it is and mount 2:nd lnb for 13E on the side. Standing in front of the dish the 13E lnb will be on the left side.
Good luck!
 
S

Sergei

Member
Messages
2
Likes
0
My Satellite Setup
none
My Location
Glasgow, UK
#3
Thanks,
I guess there is not standard on LBN arm shape then? May be someone knows size of the Triax's LBN arm off the top of their head? - it looks rectangular to me and may be mine is roughly the same... I was hoping to find this info on Triax site but it seems to be down?

I tried Sirius today with one LBN i have and it appears signal is a bit weaker (hten hotbird)

Question:
by how much signal will be reduced using LBNs with say 6,8 or 14 degrees (say I want Sirius and Astra 19 degr East) separation.
There must be a simple graph somewhere on the Web? E.g. aerial amplification (D:cool: by LBN offset in degrees.. - or something like this.
I asked in the shop I bought receiver from and they say I may need a bigger dish if I use 2 LBNs.

Or from experience - does using 2-3 LBNs require bigger dish generally? by how much?
I only have an 85(88) cm dish.

Ta
Sergei.
Glasgow.
 
S

steffo78

Regular Member
Messages
71
Likes
0
My Satellite Setup
28E 19E on 120cm Gibertini homemade sidemount with Gibertini feedhorn, Inverto C120. 5E 1W on 85cm triax. Digiality VC-CI 204 and Triax dvb-65s receivers. Matrix-cam not working. Swedish Canaldigital "local", Norwegian Viasat.
My Location
Sweden/Norway,Telemark
#4
I dont know the numbers and have never seen any ony on this subject.
The easiest way to know is to take a tv outside so you can try with lnb connected. I tried this and it is not hard with a steady hand to get results. I use a 5" b/w monitor which I bought for 4£. Just be careful not to obstruct your dishs view towards the satellite, standing under a offset dish is ok.
Make sure that you have the channel you want to receive on, and make sure you are using the right input on your switch (if you have one).

The triax arm is rectangular and also "going through the dish". dont know any measurements. The Triax dish also has rivets between dish and backmount.
 
rolfw

rolfw

Believe it when I see it Admin.
Staff member
Messages
37,726
Likes
1,291
My Satellite Setup
Technomate 5402 HD M2 Ci, DM7000s, Transparent 80cm Dish, Moteck SG2100 DiseqC motor, lots of legacy gear. Meters: Satlook Digital NIT, Promax HD Ranger+ spectrum analyser.
My Location
Berkshire
#5
Don't think that the Triax offset arm will fit any other dishes, as it uses the standard Triax plastic plug mount, I'm sure that there are others around though.

From your location you will probably be just about OK, set Sirius as the main focus and Astra 19.2 as the offset.
 
Top