2old4this
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Here are a few tips for best reception of satellite broadcasts. I invite professionals or keen hobbyists out there to add to the list.
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- use the lowest noise LNB you can get (but beware: some LNBs quote average noise rating, some quote minimum, and they rarely say which...
- rotate LNB to optimum skew position . Optimum angle depends on the satellite and your location: see (eg) the SMWLINK program from Swedish Microwave site - links elsewhere on this board.
- use only high quality sat co-ax cable (don't use standard TV coax)
- ensure there are no breaks/connectors in the co-ax between LNB and receiver
- keep the co-ax as short as possible (any longer than 25m and you should consider installing an in-line signal amplifier)
- ensure there are no sharp bends in the co-ax (different cables have different ratings indicating the severest curvature they can tolerate without signal degredation)
- avoid any possibility of water ingress by (a) not damaging the co-ax sheath anywhere along its length and ( masking the connector at the LNB with waterproof mastik (or similar).
- use solid dish rather than mesh - solid is at least 20% better than a mesh dish of same size
- use a Gregorian dish (those with a sub-reflector) if size is a limiting factor - a Gregorian is 20% better than a normal offset dish of same size.
- check alignment of dish is optimal, using preferably a signal meter or else the "wet-towel method". The latter entails masking off progressively more of the dish using a wet-towel (water absorbs microwaves) so that the reducing signal arriving at the LNB necessitates a finer dish adjustment.
- avoid any intervening objects (trees, windows...). And beware if you have an offset dish and think it is neatly aligned to a gap between/under some trees... a prime-focus dish has the LNB in the middle, but an offset dish has the LNB at the bottom, so receives a signal that comes in from the top (reflected downwards to meet the LN. So such a dish might appear to be "looking" directly at a blank bit of sky, but actually needs a clear view to the bit of sky ABOVE where it seems to be pointing (ever wondered why when watching sats close to the horizon the dish seems to be pointing at the ground?)
2old
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- use the lowest noise LNB you can get (but beware: some LNBs quote average noise rating, some quote minimum, and they rarely say which...
- rotate LNB to optimum skew position . Optimum angle depends on the satellite and your location: see (eg) the SMWLINK program from Swedish Microwave site - links elsewhere on this board.
- use only high quality sat co-ax cable (don't use standard TV coax)
- ensure there are no breaks/connectors in the co-ax between LNB and receiver
- keep the co-ax as short as possible (any longer than 25m and you should consider installing an in-line signal amplifier)
- ensure there are no sharp bends in the co-ax (different cables have different ratings indicating the severest curvature they can tolerate without signal degredation)
- avoid any possibility of water ingress by (a) not damaging the co-ax sheath anywhere along its length and ( masking the connector at the LNB with waterproof mastik (or similar).
- use solid dish rather than mesh - solid is at least 20% better than a mesh dish of same size
- use a Gregorian dish (those with a sub-reflector) if size is a limiting factor - a Gregorian is 20% better than a normal offset dish of same size.
- check alignment of dish is optimal, using preferably a signal meter or else the "wet-towel method". The latter entails masking off progressively more of the dish using a wet-towel (water absorbs microwaves) so that the reducing signal arriving at the LNB necessitates a finer dish adjustment.
- avoid any intervening objects (trees, windows...). And beware if you have an offset dish and think it is neatly aligned to a gap between/under some trees... a prime-focus dish has the LNB in the middle, but an offset dish has the LNB at the bottom, so receives a signal that comes in from the top (reflected downwards to meet the LN. So such a dish might appear to be "looking" directly at a blank bit of sky, but actually needs a clear view to the bit of sky ABOVE where it seems to be pointing (ever wondered why when watching sats close to the horizon the dish seems to be pointing at the ground?)
2old