Dggrr
Member
- Joined
- Sep 2, 2006
- Messages
- 59
- Reaction score
- 68
- Points
- 18
- Age
- 70
- My Satellite Setup
- VU + Zero, Triax TD88, Technomate TM2600 (Plus CM 1.2 in bits behind the shed)
- My Location
- SE
I have an 88cm motorised dish but have found that I am missing many lower power feeds in the SE UK.
So I have set up a 1.2m dish with a prime focus of 10 East and a second LNB on 7 East. This seems to be working well.
Surprising there seems to be little information on the losses of an off-prime focus LNB for orbital separation.
The only factual reference I have found is Multiple Satellite Feed Systems – SSE who quote a 1db loss at 3 degrees. However, this is for C Band and centre fed dish, not Ku band and offset.
Most multi-LNB setups seem to address commercial broadcasts and not feed hunting, for good reason of course.
Any thoughts on this? For example, if I added a 3rd LNB to my 1.2m dish for 16 East with the prime focus at 10 East, would I see any benefit over the motorised 88cm dish which is always at primary focus?
For the sake of argument, let's assume that any LNB placement at focal length and skew are perfect
So I have set up a 1.2m dish with a prime focus of 10 East and a second LNB on 7 East. This seems to be working well.
Surprising there seems to be little information on the losses of an off-prime focus LNB for orbital separation.
The only factual reference I have found is Multiple Satellite Feed Systems – SSE who quote a 1db loss at 3 degrees. However, this is for C Band and centre fed dish, not Ku band and offset.
Most multi-LNB setups seem to address commercial broadcasts and not feed hunting, for good reason of course.
Any thoughts on this? For example, if I added a 3rd LNB to my 1.2m dish for 16 East with the prime focus at 10 East, would I see any benefit over the motorised 88cm dish which is always at primary focus?
For the sake of argument, let's assume that any LNB placement at focal length and skew are perfect