Sky Satellite Bad Reception

rinkrat

Hi

I have had normal sky installed and working ok for a number of years. Recently I started to get Inerferance on vision and sound, but only on certain channels and during heavy rain. Its now got to the point however where the interferance is present just about all the time, but again its only on certain channels. Sods law says that its the channel that I want to watch something on tho.

Is this what is called pixalation ? If so am I right in thinking that I could fit a new LNB to solve the problem. I know I can call out Sky but I am reluctant to pay what they will want to charge. I am well out of my 1 year contract terms. My receiver is a Panasonic Silver box.

If it is the LNB how easy is it to fit a replacement. I have had a quick look at the dish and the LNB appears to have a plastic cover over it ! Looking on E bay there appears to be quite a few diffrernt makes of LNB for normal sky. Will any of these work with my dish. Are there any differences in quality and reliability of the different LNBs

Thanks in advance for any advice.

Rinkrat

Browntoa

it may be something like a tree that has grown in the line of sight to the satellite, hence the gradual decline

it is not unusual for Sky to vanish when there is heavy rain , I had to scrape snow off mint the other week to get the signal back !!

chilli_dog

think sky use screw on connectors with some special tape wrapped around it. might be worth checking you connections at the dish and possible renewing them. not a hard job have done it when we moved the house round and wanted skey in another room

andrewmoorcroft

hi mate,
as a sky engineer i can almost guarantee the problem is your LNB. when they become faulty it is still possible to receive signal but usually bad quality and the problem will be exsasperated by moist conditions and water ingress, causing problems from pixelating picture to "no sat signal being received" intermitently. most sky engineers dont pay for single LNBs and are usually happy to hand one over if you ask nicely.
things to remember when changing an LNB:

1) be very careful not to alter the dish's alignment when removing the old one as some are a very tight fit and need "man handling". If you knock it out of alignment you have almost ZERO chance of realigning without a signal meter (the one in the services menu is NOT accurate enough)

2) ensure that the connector is tidy and NONE of the coax outer sheilding comes in contact with the centre core.

3) the connector will usually be sealed in cohesive waterproof tape- there is no need to remove this if you remove LNB first and unscrew the LNB from the connector rather than unscrewing the the connector from the LNB- you got that? Then obviously reverse the process to refit the new. Failing that, as long as it's wrapped in plenty of insulation tape you shouldn't have a problem.

4) make sure you have the correct collar for your LNB to fit your dishes arm. (some dishes don't require a collar at all.

hope this helps

any further questions, or to book half price service calls in the Midlands PM me with your contact details.

thanx

jjames_3

Or, the problem could be the cable itself.

Long lengths of sat cable, particularly old or poor quality installations, can be prone to not delivering enough current to the LNB in horizontal mode, so that the LNB will send down the vertical signals (these being a lower voltage than horizontal; to switch the signal from vertical to horizontal LNBs take a 13v supply for V and 18v for H).

So you'll find that sometimes, especially in poor weather, horizontal channels (randomly assigned as far as the viewer is concerned) won't work correctly, either not coming on at all, or working intermittently.

andrewmoorcroft

jjames wrote:

Or, the problem could be the cable itself.

Long lengths of sat cable, particularly old or poor quality installations, can be prone to not delivering enough current to the LNB in horizontal mode, so that the LNB will send down the vertical signals (these being a lower voltage than horizontal; to switch the signal from vertical to horizontal LNBs take a 13v supply for V and 18v for H).

So you'll find that sometimes, especially in poor weather, horizontal channels (randomly assigned as far as the viewer is concerned) won't work correctly, either not coming on at all, or working intermittently.

This blokes 'aving a larf! Please don't confuse the matter. I've done over 200 service calls this year and not once changed the cable unless there is obvious damage. It takes much longer to change the cable than an LNB and there's more chance of creating a dodgy connection. I guess 99% of calls with your syptoms are fixed with a new LNB.

mcerazer

hi i get a "no sat signal being received" on most channels now they go after 15mins or so and come back after while whats wrong with it ! and whats a "LNB" ???

thanks !

rinkrat

Thanks for all the replies. Looks like as I thought its most likely to be the LNB.

There seems to be lots of different ones available on E Bay. Raven and cambridge etc. What should I get will they all fit the same dishes ? Does the LNB just pull out from the arm ?

The lnb currently on I think looks like it has a cover around it ( more like cambridge than raven )

Thanks

andrewmoorcroft

mcerazer wrote:

hi i get a "no sat signal being received" on most channels now they go after 15mins or so and come back after while whats wrong with it ! and whats a "LNB" ???

thanks !

The LNB is the lump on the end of the arm that sticks out from the dish that the wire comes from.
Dishes and LNB's are virtually free issue to a sky engineers and it is worth asking next time you see a sky van. If the're not very forthcoming a fiver should do the trick! The're are also contractors for depending on area. Contactors will have spare LNB's also.

jjames_3

andrewmoorcroft wrote:

This blokes 'aving a larf! Please don't confuse the matter. I've done over 200 service calls this year and not once changed the cable unless there is obvious damage. It takes much longer to change the cable than an LNB and there's more chance of creating a dodgy connection. I guess 99% of calls with your syptoms are fixed with a new LNB.

'Aving a larf, dear me.

I've seen a number of systems like this.

Are you disputing the fact that overlength cables cause problems with polarisation?

On my own system at home, I had Sky out on several occasions replacing LNB, box, LNB again, LNB again, all the while replacing the F-connectors and amalgamating tape each time.

On each occasion, having seen and repaired the same problem on my own Diseqc multisat system and others (mostly single-sat only), I mentioned the cable as the source. Each time I was met with the same response as you've just given.

Guess what the cause was in the end?

Tsk.

skyguy

andrewmoorcroft wrote:

hi mate,
as a sky engineer i can almost guarantee the problem is your LNB. when they become faulty it is still possible to receive signal but usually bad quality and the problem will be exsasperated by moist conditions and water ingress, causing problems from pixelating picture to "no sat signal being received" intermitently. most sky engineers dont pay for single LNBs and are usually happy to hand one over if you ask nicely.
things to remember when changing an LNB:

1) be very careful not to alter the dish's alignment when removing the old one as some are a very tight fit and need "man handling". If you knock it out of alignment you have almost ZERO chance of realigning without a signal meter (the one in the services menu is NOT accurate enough)

2) ensure that the connector is tidy and NONE of the coax outer sheilding comes in contact with the centre core.

3) the connector will usually be sealed in cohesive waterproof tape- there is no need to remove this if you remove LNB first and unscrew the LNB from the connector rather than unscrewing the the connector from the LNB- you got that? Then obviously reverse the process to refit the new. Failing that, as long as it's wrapped in plenty of insulation tape you shouldn't have a problem.

4) make sure you have the correct collar for your LNB to fit your dishes arm. (some dishes don't require a collar at all.

hope this helps

any further questions, or to book half price service calls in the Midlands PM me with your contact details.

thanx

i was using my friends login earlier

Just thought i should mention:
by the time you've paid £10 with p+p for your LNB, spent 1-2 hours of your valuable time fiddlin' around doing a job you're not familiar with, risking your !!!!!! up a ladder or on a roof (remember the lessons from our dearly departed Rod Hull- Emu's can't fly, even if you've got your arm stuck up 1!), increasing the likelyhood of dish alignment or connection problems-
you might as well call your local aerial engineer and offer him £30 cash to do the job. he'll ensure your dish alignment is correct and be gone in 1/2 hour, work guaranteed!
Having the instructions to do a job doesn't make you an engineer- remember folks, if my job was that straight-forward, i wouldn't have one!

*nb- probably 1/2 the LNB changes i do are to dishes that could have the alignment improved (though not always necessary for operation), sometimes dishes do weather loose.
- all the problems that have been mentioned on this thread could ultimately be Set Top Box problems, though not likely this should be remembered, the only way to be sure is by a process of elimination which requires the use of an accurate signal meter.

so i guess i won't stop the have-a-go DIY hero's from having a go (after they've fixed the door they hung last summer that wont close properly, and never did. oh and don't forget the light switch that switches your fridge off even though you read the instructions!!!) but if you've got sense and you earn £10ph, come on, you do the math!