nadal liu
Regular Member
- Joined
- Jan 16, 2014
- Messages
- 38
- Reaction score
- 3
- Points
- 8
- My Satellite Setup
-
120cm offset dishes for 124e and 128e with emp centauri profi multiswitch 9x16, and 5x20
,180cm prime dish with lo 10678 ku lnb for 110e bs/cs
- My Location
- Hong Kong
I was asked the question: why with prime focus dish we need to adjust lnb position to find the focal point, but with offset dish there is fixed mount that is not adjustable?
This is always a known fact and I never gave it a thought and I took it granted.
The friend asked me that he said the reason could be prime focus dish can be used with ku and c band and that the focal point could be different for the two, but I doubt it.
My guess is that offset dish is usually smaller and even if the lnbf position is off from the focal point, the distance off is smaller.
Please advise.
This is always a known fact and I never gave it a thought and I took it granted.
The friend asked me that he said the reason could be prime focus dish can be used with ku and c band and that the focal point could be different for the two, but I doubt it.
My guess is that offset dish is usually smaller and even if the lnbf position is off from the focal point, the distance off is smaller.
Please advise.