my picture pixelates but only on some channels?

The previous answerer was correct in part - that is to say your should ignore his answer about SCART cables. :-)

It is not your SCART cable because that fault is not technically possible.

The pixelation will be caused by a weak signal. You need to check antenna/dish alignment and the cables and connectors from it to the receiver.

T
December 2009

Not necessarily - a broken picture suggests a broken signal. You obviously have a weak signal somewhere - any system component / connector / cable / junction may be contributing to make the signal even weaker.

Wikipedia has an article about SCART cables - it says gold scart connectors can be good but ONLY if the connection is gold to gold - else nickel to nickel - gold to nickel tends to promote corrosion because of dissimilar metals.

I know nothing much - you may ignore my answer.

Good luck...

Peccavi
December 2009