UK Sky satellite TV conundrum

[SpringHeeledJack]

Evening all

I figured this would be the place for such a query, but if not, mods please move onwards. TV was playing up this morning, picture breaking up, then ok, then breaking up during heavy rain. It has done this a few times before, but after 30mins the signal comes back and all good. However today it didn't, and no amount of re-setting and waiting changed the fact that NO satellite signal was being received. The signal test function showed no signal at all..... The dish is as was, the cabling also ok with no breaks and mating with the ports at each end as always. I dismantled the LNB unit from the dish and checked it visually and there seems to be no cracks where rain water might get in, but after that I've drawn a blank. Any ideas chaps ?

[vulcanised]

If it's given intermittent trouble before due to weather conditions I would guess whatever it was has finally gone TU.

My guess (and it is that) would be the lnb has failed.

[M.Mouse]

Assuming you are in the UK.

Rain attenuates a satellite signal quite dramatically. If your setup was weak to begin with for some reason this would explain your signal disappearing in rain.

Is the dish alignment good? Is the cable good quality (cheap cable can cause all sorts of problems)? If the answers are yes then it points to a faulty LNB or receiver, the LNB being the prime suspect. Cheap enough to replace at under £25.

Be sure to buy the correct one i.e does it have several outputs and if so is it feeding a distribution amplifier or do the cable(s) run direct to the receivers. Generally a distribution amplifier requires a 'Quatro' (as opposed to a 'Quad' LNB).

Dishes are also cheap and another general rule is that a larger dish gives a dramatically better signal improvement over buying an LNB with a better signal to noise ratio.

Let us know how you get on.

[spekesoftly]

I can certainly endorse the above comment about dish size. A standard (zone 1) Sky mini-dish is about 45cm. Mine is 65cm, and even in the heaviest of rain or snow storms, signal quality and reception remain excellent.

LNBs for Sky mini-dishes have a number of different collar fittings where they attach to the arm, so check compatibility before buying a replacement. Quads available from about £10, so worth a try.

If you are going to check your dish alignment, I suggest you mark the fixings before making any adjustments, so that you have reference points to return to, using the "trial and error" technique!
Very small movement can make a big difference. Even a cheap signal meter (mine was under £10) makes this job much easier. LNB skew (rotational position in the collar) and focus (fore and aft movement) also need adjusting for best performance, and again a meter helps to get these spot on.

[Cameronian]

Does anybody else have problems getting a signal from the "Military" channel on Sky. I get nothing whatsoever but yet the box doesn't crash as it normally does if a channel's signal is seriously compromised. There is no disturbed image either, just an absolutely clear screen but the situation is perfectly recoverable, even after a significant delay on that channel, simply by switching to another channel - no need to recycle the box.

Oh dear, there's me hijacking a thread again - sorry!

I second the advice about dish size but would add that quality really does count as well. I had an issue, which turned out to be a duff LNB, and the tech told me that when he saw my 85cm. dish he just knew that he'd never get a good signal out of it. He confessed to having been proved wrong and said that my dish was a star because it gave a signal typical of a 110 or 120cm. one. New LNB and the job was a good 'un!

[Lon More]

Does anybody else have problems getting a signal from the "Military" channel on Sky.

I'm not able to get all the channels either. I've always assumed that not all channels have the same strength and the rx of them may largely be location dependent

[SpringHeeledJack]

Military channel :confused: Am I missing something here, or do you need special access ? :suspect:

Back to the thread.....So, after a few ladder excursions and not a little bad language I'm ashamed to admit, the LNB was detached, re-attached, detached, taken to a little satellite/TV shop locally. They couldn't test the LNB unless it was attached to a dish. Then, on their advice I brought the skybox to them, it was hooked up and tested ok. They then suggested that squirrels might have bitten through the cable, although this proved not to be the case on checking (after much bad language). They then offered to give me a used LNB to try out, to "see if it works". Brought it home, dropped it on my foot, it really hurt, and after even more bad language I reconnected the new old LND and BINGO!!!!!!!

Somehow the water was getting into the previous LND and disrupting the transfer of the signal. One question, on using the 'Signal Test' facility I noticed that whilst the signal strength is approx 80%, the signal quality is about 20%. However the picture quality is fine, at least to my eyes. Any idea as to why the signal quality shows as so low ?



SHJ

[Spitoon]

If it's of any help Astra - the operator of the satellites that Sky comes from - has a simple guide to installing a dish and LNB - How to receive - SES ASTRA (http://www.onastra.com/how-to-receive). I'm outside the UK and found that the LNB skew (rotating the LNB in the collar) made a huge difference to the strength/quality of the signal - this is less significant for receivers in the UK but may still be worth getting optimal if you lose some channels in heavy rain etc.

[M.Mouse]

SHJ, pleased you have nailed the problem. The signal quality can be affected by several things.

Firstly, was the used LNB you were given a good one? New ones are not very expensive.

Secondly, as mentioned above, 'skew' is another area to look at. Simply put satellite TV signals are polarised either in the vertical plane or the horizontal plane. The LNB must be aligned i.e. 'skewed' to match the angle of the polarisation.

Use this link (http://www.dishpointer.com/)which will tell you the azimuth, elevation and skew angles for your exact location (select the Astra Satellites at 28.2°E). The skew is normally only a few degrees and from the link the direction of rotation is viewed from behind the dish and minus is anti-clockwise. Some LNBs have degree markings on the body but if not think of a clock face and each minute mark represents 6° to help you visualise the amount of skew needed.

If your signal quality is low and are getting a picture it is because there is sufficient signal to get a picture. Bear in mind digital signals give a picture or not they will not give you a fuzzy poor picture but if the signal is too weak your picture will freeze or start becoming 'blocky'.

Given your previous comments about losing the picture during rain I suspect, LNB, cable and dish being satisfactory, that you have an alignment issue. You are in the UK I presume?

[SpringHeeledJack]

Thank you all for the helpful replies and links. Yes one is in the UK, and as such it's dark outside now, so will wait for the morn before getting up the ladder again. It seems, on a brief flick through the channels that every few along are unavailable, so there's definitely scope for improvement through adjustment. If the old new LND is causing missed channels, then a replacement SKY Thompson will be purchased from fleabay forthwith. Maybe it's time to swap over to a Virgin bundle, as my internet with Sky doesn't go higher than 0.88mbs and that tivo box with V is perhaps a good idea. But then I wouldn't be able to climb ladders :hmm:


SHJ

[Mike-Bracknell]

IIRC if you're missing several channels then half of your LNB is most probably buggered (given that they have a horizontal and a vertical plane for channel reception).

Also, I found it useful to put Sky on the service menu showing the signal strength and quality, and get up a ladder to adjust the dish whilst watching the outcome (noting that it takes a good 3-4 seconds for the result to be displayed). I now have an almost perfect signal strength and quality from a standard dish.

[M.Mouse]

Your internet does of course come down your telephone line!

[SpringHeeledJack]

Ha ha, indeed it does, just moaning out loud about the various dis-satisfactions with my Sky bundle, but too typically lazy to do the switch up until now. Who knows I might well become a 'switcher' one of these days soon.



SHJ

[SpringHeeledJack]

A question for the team!

Over the last weekend the signal disappeared at night for several hours on both friday and saturday and strangely this coincided with a large firework display some 500 meters away. I don't see how this should be, but surmised that somehow the particles of exploded fireworks were disrupting the signal somehow, although disruption was for some hours. Any theories or just down to chance ?



SHJ

[Spurlash2]

Link HERE (http://www.space.com/13517-giant-sunspot-unleashes-massive-solar-flare.html).

Some text from the article;

A powerful solar flare that erupted Thursday (Nov. 3) from a huge blemish on the sun's surface has been classified as an X1.9 flare, ranking it in among the most powerful types of storms from our star can unleash.

The flare originated in a humongous sunspot that was sighted earlier this week, which ranks as one of the largest sunspots seen in years. The event began at 4:27 p.m. ET (2027 GMT).

The flare "triggered some disruption to radio communications on Earth beginning about 45 minutes later.