Looking to replace our LNB as think its past its best.

Are they all much of a muchness or are there 'known good' makes to go for?

Cheers

I just bought one from Maplin for convenience when ours failed. More cost effective sources are available, I'm sure. IIRC, it was a FortecStar twin output job and I'd forgotten I'd changed it a couple of years back, so I guess it's working OK.

It really depends what type of dish you have and what mounting the LNB comes with.

Sky minidishes have a square lug that pushes into the end of the support arm. Most generic dishes have a circular clamp for the LNB. You can get adaptors to fit one to the other, but..

In theory, Sky minidishes require a different feed horn arrangement in the LNB because they are not circular but oval. In practice this probably doesn't make a huge difference and you may well get away with a generic LNB on an adaptor. I did.

When setting up, bear in mind that the LNB needs to be positioned accurately at the focal point of the dish and it needs to be skewed at an angle to give the best separation of the H and V polarisation signals. The amount of skew depends on your location.

It's a good idea to get a strength meter and "tune for maximum smoke" for dish azimuth and elevation, LNB distance from the dish, then swap between channels with H and V polarisation and try and get the best compromise of signal strength and quality by adjusting the skew. Repeat that sequence a couple of times to get the best signal that you can (even if it's properly aligned, you may well knock it out of alignment when wrestling with the LNB).

Kevin

For those of us who haven't got a feckin clue what he's on about, it's a low noise block downconverter.

Of course, it goes without saying that, if you suspect the LNB to be deteriorating, don't overlook the fact that the dish could need aligning, or the coax could have deteriorated. A bit of investigation could save a few quid if you haven't eliminated these.

Kevin

Cheers all, some good advice there, not looking forward to trying to improve the dish alignment.

Our pic breaks up far too easily, so thought I'd replace the LNB as a starting point, then move on to tweaking the dish.

Ive got one of those little satellite stength meters, but have read conflicting reports, some saying they work well for the whole job, some saying they get you in the ballpark, then use the one built into the sky box to fine tune.

Most the ones on ebay report to be a direct replacement for sky minidishes now, so should just be a case of getting the settings off the old one and applying to the new, swap the cables etc over, and away we go.

Be a few weeks off anyway, as there is a birds nest behind the dish at the mo, and Im not going to disturb the eggs.

Jimbob wrote on 05. Apr 2011 at 08:23:


Take a reading at the LNB and one at the sat box.....to rule out the cable.....

Jimbob wrote on 05. Apr 2011 at 09:07:


The standard sky twin stuff is usualy not to bad but, there not the greatest installers!

here's a good site on pointing a dish http://www.satsig.net/spectrum-analyser.htm