LNB arm lengths unknown ..?

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VS - one question begs itself - perhaps it is borne of not having followed your merits since once upon a postings began...
But why are you faffing about with a 1.1 lightly damaged Maxx steel dish, when you have a 1.2 meter Channel Master sitting around doing pretty much nothing?
 

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Vipersan

Emmett Browns Ghost
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My Satellite Setup
IP9000HD +
TD110 Dish and TD88 Dish in Tandem
66°East to 60°West.
AZbox PrmHD + OpnbxS9HD + Skybox + DrHD F15
2x VboxII AZ-EL
2 m+ Alcoa PF + BSC421 C-Band lnbf...
+SS2/TwHnS2-3200 pci/TBS6925 pci
1.5 Fortec Star -Gbox - HtoH Ku/Ka/C
My Location
UK
In answer to your question ...
I cannot mount a Channel Master on a usals motor ...
Its to big and heavy ...
Plus the CM is damaged / cracked and I dont have all of it .. ..and it would require some serious repair ..
lastly the 1.1 is a freebie and as such I want to use it at height for L band reception so why not use it as it is unsuitable for much else ..
The surface isn't smooth enough for Ka for example ..but at L band frequencies ..the imperfections are less important.
I also own a Gibby 1.2 ...and this can't be mounted on a usals at height for the same reason..
Too big ..too heavy.
You have to keep in mind my space limitations ...so some stuff _has_ to be wall mounted ..
rgds
VS
 

Vipersan

Emmett Browns Ghost
Joined
Jun 29, 2009
Messages
10,918
Reaction score
6,663
Points
113
Age
66
My Satellite Setup
IP9000HD +
TD110 Dish and TD88 Dish in Tandem
66°East to 60°West.
AZbox PrmHD + OpnbxS9HD + Skybox + DrHD F15
2x VboxII AZ-EL
2 m+ Alcoa PF + BSC421 C-Band lnbf...
+SS2/TwHnS2-3200 pci/TBS6925 pci
1.5 Fortec Star -Gbox - HtoH Ku/Ka/C
My Location
UK
So ..had a go with the furmula I found online :-

Focal length = (width ^ 3) / (16 * depth * height)


In my case (cm)

FL = (106^3) / (16 x 9 x 115)

FL comes out at approx 72cm ...
So my LNB arm although working is too long so illumination is starting too far back by about 8cm ...
this illuminating the wall behind the dish in part ..

I will now replace the ally temporarily with a piece of wood cut to 72 cm ...to test ..
IF the rain ever stops ..

The anglular position of the lnb is another question ..but shall use the same angle as the one mtr Orbital as a start point ..

This is just by way of experiment to see if I can squeeze a bit more from the dish ..

;)
 
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