mike48t - 08 August 2008 10:23 AM
There are a lot of factors involved here, Channel 4 and 4+1 are prone to problems later in the day, usualy around 5 to 6PM. It is unusual though for 4+1 to give problems. I have notice for the first time this year that CH4 is breaking up slightly around this time, but 4+1 is ok. So it may be a generic problem that is being noticed on smaller dishes and poor setups!!
There was an argument in What satellite magazine some time ago that said the problem was due to batteries in the Sat, in that the Sat was changing over from PV power off the Solar panels to battery power and the suddenly drain was causing a voltage drop and it was taking time for that to recover,the batteries had been up there for over 13 years needed changing(True on not? I dont know).
However to your problem, It could be that your dish/lnb has moved very very slightly, so the first thing to do is just handle your dish in various directions to see if there is any movement in the bolts and adjusters ,tighten up gently if necessary(NB but not flexing that is something different) . The next thing is you to check that no Spiders and the like have started building works up the tube of the LNB(most now have plastic caps so it shouldnt be a problem)
Channel 4 is usually a matter of skew ( turning you LNB clockwise or anticlockwise until the signal is right, these movement are miniscule and even 1/10 of a mm can make a difference, the other issue can be if you go to far the “right” way you can lose other channels particularly SKY three
You can adjust Skew by slackening off the LNB holding screws and making small movements(Mimniscule) check improvement or not on the picture until you optimise, nb it is important to check your other favourites are still there at the same time.
THis is a very delicate operation and will for the inexperienced take patience time and perseverence.
You could try doing a manual scan for Channel 4 on 12168 V 27500 2/3. There are now unencrypted versions there and your receiver may need updating.
I must warn again that if you start moving the dish and components you do risk losing all and then will need an engineer to sort it out for you.
I have some more info on this now, CH4 has been since about Jul changing frequencies and Sat positions in readiness to go Free to Air (No Sky card needed), so it could be you are a victim of that,m
If you have a SKY box you can obtain these channels by adding the channels to your off EPG (TV guide List)
You can do this by
with your system switched on, put it on SKY news CH 501. then press the blue services button
this will bring up a menu, select no 4 system set up,
this will bring up another menu with an option on it marked add channels, using the blue arrows up/down select add channels
This will bring up another menu, on the first line change the frequency to 10729 , , then using the blue up/down and left/right buttons, change the Polarisation to V, the Symbol rate to 22 and the FEC rate to 5/6 Then select channels
This will give you a selection of channels to store, select 8350 using the yellow button, when this is complete press select and then the big SKY button. ( you should now have added Channel 4 to your list of other channels)
Next follow the same procedure as above, but use the Frequency 12479, V, 27.5, 2/3, when you hit the find channels button this will bring up a selection of CH4+1, select all of them using the blue up/Down arrows and then press the yellow button a tick shoudl go by the side of the channels selected, then press select, and then the big sky button,, You have now added the new CH+1 frequencies to your other channels programme listing,
Pressing the big sky button should have taken you back to the programme you were watching, Sky news ( if this is not so press the back up button a few times to ensure you are out of the services menu), so now we need to see the channels we have selected
Now to confirm that all is ok, Press the services button on your remote control, a menu should come up with a selection available saying other channels,
Using the blue up/down button select the channels you want to watch,
For Channel 4 select the channel showing 8350,
For Channel 4+1, select whichever one gives you the best picture,
NB It is important you dont go into other areas of the menu when setting up the add channels,
good luck