Why does my TV jump

[zlsmith]

Hi,

A lot of the time my TV jumps. Some days its fine but some days the picture and sound jumps. If I fiddle with the cable that is connected from the back of the TV to the aerial outlet sometimes I can get a picture. I have attached a new cable so I know it's not that. Could it be my aerial outlet or my outdoor aerial? Or something else? It has been like this for years and very confusing as I know nothing about TVs and aerials.

Thanks.

 

[Onus]

It isn't wearing Kangaroo Shoes is it?

More seriously, is this an older CRT-TV? If so, check the horizontal and vertical hold (if it has those). Cold solder joints can cause this.
This may not be a great forum for this type of question though, as we mostly deal with computer-related issues. We do have a few electronics guys around (e.g. Retired Chief), but Google or another forum may have more or quicker answers for you.