Strange doings at night

DMC

A mate of mine has a Sky installed, and over the Christmas, the picture was prone to break-up to the point of being unable to watch, but this was only on channels like Sky Sports 1, Sky Sports News, Sky Sports Extra and Sky News. Low frequency channels, like the BBC's and RTE are fully ok.

I asked him to note if there was wind and rain, but the dish is quite sheltered. I went out on Saturday and checked the signal quality and strength level on the box, around 70/80%, which I confirmed with my Lidl FTA receiver, and when I looked at the specific frequency the Sky Sports channels, it was at 75%, which is good enough. I checked the LNB and cable for water damage, and it seemed fine.

On Sunday, when there was a little bit of rain, and he rang me to say it happened again.

Things to note, to recap.

• It only happens at night
• It only happens to high-frequency channels
• Last night, when there was a full blown gale blowing, it never broke up once.

Any thoughts?

watty

He isn't anywhere near any SCTV or similar stuff?

Or it could be at IF on the cable and only on some Hi Band, not the same range of IF is used on both bands.

DMC

He's in Drogheda, so I don't think there is anything similar to SCTV in the area.

Ulsterman 1690

Could be a faulty LNB (less sensetivity on the higher frequencies) this wouldnt show up on a bog standard signal meter as these detect an average level across the whole band.

Another possibility is a faulty tuner in the digibox (try borrowing another box and plugging it into the existing dish to see)

A third possibility is crap quality cable between dish and digibox (would affect higher channels first)

kbell

Is it a Thomson single lnb on his dish?
A common symptom of a faulty thomson lnb is picture breakup on high freq channels even in the in lightest of rain.

byte

I think Ulsterman1690 has pretty much summed up all possibilities.

Maybe use the FTA box on Sky News which is FTA, see if it breaks up when it rains.

I have seen crap cable or poor joints (twisted together cables) causing severe signal loss, though I used to find this affecting the Beebs, RTE's etc moreso. Water ingress also to be considered.

netwhizkid

kbell wrote:

Is it a Thomson single lnb on his dish?
A common symptom of a faulty thomson lnb is picture breakup on high freq channels even in the in lightest of rain.

I had the problems described by the OP with a thomson single Sky LNB, It was a curse and the likes of the MTV's and the History Channel were worst affected. I tried my Grundig Digibox on a different Dish and it was perfect, It was a very intermittent fault and changing the LNB fixed it.

I made Sky pay for the LNB by threatening to cut off the subscription at home and they sent out the engineer who replaced the LNB. (I have two subscriptions at two different properties). However can be got for €25 so your mate shouldn't be too much out of pocket DMC.

cast_iron

The LNB / box combo can be very finicky really.

I know of my 2 dishes/boxes, 1 LNB would work with both boxes, the other LNB would only work with one box.

So, in essence, both LNBs and both boxes worked - but only in a certain combination. Impossible to say with certainty whether it was the LNB or the box. (My money is on the LNB)

Never a days bother thereafter (until the older box died, that is).

Rippy

watty wrote:

He isn't anywhere near any SCTV or similar stuff?
.

Luckily, I have not had any calls yet of satellite malfunction that I can put down to SCTV Digital. I am currently doing about 5 satellite service calls a week around Carrigaline. All have been resolved as the usual problems, misalinged dishes, bad cable and connections , faulty receivers and LNBs.
I did have one the other day where the complaint was channels breaking up.
Looked at the dish and a SCTV dish had been fixed beside with the LNB almost in between the reflector and LNB of the sky dish. I was not best pleased and assumed the worst, but it tuned out to be a faulty LNB (on Sky dish). I did move sky dish lower down the chimney just in case!
I think I can cautiously say that it is not now likely to cause problems.

Rippy

I have also found thomson single LNBs often give probs in the high band.
The old deep rather than wide grundig (about 5 years old ) seems the best sky LNB I come across.