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F/D Focal point on prime focus dish

dave branson

Regular Member
My Location
Florence Italy
I have a 1.8 irte prime focus dish,when i calculate the focal point using
using the programme of satellites-comunications.com,it gives a focal length of 67.5 cms.
On checking the my dish the focal length is some 75 cms.
At the moment I get BBC/ITV during the day,goes off about 19-00 hrs,
in the winter it lasts a lot longer,but thats another dicussion.
I am using a Invacom quad and adjustable feed horn,which is at maximum on the lnb bracket,( set to 0,41 f/d ) leaving the focal length
at 75 cms.
so my question is ,is the focal length very important, if so,where can i get a longer feedhorn.


cerca trova...
Staff member
My Satellite Setup
Triple Dragon, Dreambox 8000, Echostar AD3000ip, TBS6522,6925,6983 PCie cards.
Gibertini 1.25m motorised dish driven by the AD3000, with either Inverto BU Quad or Norsat / XMW Ka LNBs . SMW 1.05m + 3 other dishes. Speccy: Promax HD Ranger+
My Location
The Flatlands of East Anglia
You'll need the C120/120 adaptor to match waveguide to Invacom LNB.