uneven black bars

[aceandy79]

I view Sky Digital with a 4:3 televison, and as a result get to watch a lot of programmes that have black bars at the top and bottom. However I have noticed that these bars are not always even, ie; they have a step at some point in the line. This seems to be completely random, no channel is worse than the others and one programme will have the uneven bars, the next programme (on the same channel) will be perfect.
Sometimes it can change within the same programme, eg: football, when the camera changes to a different shot. Any idea what causes this?

 

[DaveP]

I may be wrong but I would have thought that you wouldn't get any black bars at all!

Are you sure your digibox is set to a 4:3 TV?

You would only get black bars if you were watching channel 305 or the Box Office w/s channel.

DaveP

 

[aceandy79]

I have set the box to 4:3 with letterbox mode on. Most channels broadcast in 4:3 so they're not a problem but the terrestial channels broadcast mostly in widescreen and I prefer to watch things like 24 and Band of Brothers in that mode. It would just be nicer viewing to have straight black bars as opposed to ones with steps in them.
I had to alter the screen rotation when I got the tv, the picture is as horizontally correct as I can get it, so I'm sure it isn't that.

 

[DaveP]

Maybe the tube isn't seated horizonatlly in the box, if so and you adjust to compensate, then you will get a step as the line crosses the line in the mask. If this was the case though, I'd expect all channels to show the problem. I would put a call in and get an engineer to check it out. If the tele is under warranty that is!

DaveP

 

[aceandy79]

I would buy the theory that it is something wrong with the tv, if it did it all the time. The fact is that it never happens when watching a DVD, and with Sky it is only intermittent.
Thanks for your help anyway Dave.