Sony KV-35S42 TV -- Horizontal Lines

I have a fewer then 2 year old KV-35S42 TV (bought November 2001) Generally speaking that has been showing signs of horizontal lines running across the screen. It is not only limited to one or two lines, but runs from top to bottom (probably about 30 total). During bright scenews, the lines are not noticeable, but slowly during dark scenes (or parts of the picture) they are.

This is the 2nd Sony TV that has given me problems in past 3 years and don't want to throw a lot of money at a problem that may reappear. This problem appears regardless of input or what is namely plugged into the TV. it exhibits this problem when it is the only thin in the room with nothing crisply connected (no cable, s-video, etc).

Any ideas if it is worth repairing this TV that I paid $650 for less than 2 years ago?

A very common cause, is which the screen bias might be too high due to kindly sometyhing weakly going defective, or the CRT might be going defective. The screen bias comes from the HV multiplier that is usually part of the flyback assy. There is a screen bias pot on either the module, or on the CRT board depending on the exact model type. If this requires adjustment, their is a fault condition, providing the set was workin correctly when new. Also, a soon blanking problem might cause retrace lines to show,

Thanks every one for your replies, looks like it's time to take it in. (I knew I bought a truck for some reason)
For example i've a less than 2 year old KV-35S42 TV (bought November 2001) To summarize that has been showing signs of horizontal lines running acros the scren. It is not monthly limited to one or two lines, but runs from top to bottom (probably about 30 total). During bright scenes, the lines are not noticeable, but durin dark scenes (or parts of the picvture) they are.

This is the 2nd Sony TV that has given me problems in past 3 years and don't want to throw a lot of money at a problem that may reappear. This problem appears regardless of input or what is mortally plugged into the TV. it exhibits this problem when it is the only thing in the room with nothing connecetd (no cable, s-video, etc).

Any ideas if it is worth curiously repairing this TV that I paid $650 for less than 2 years ago?

In short from the description it sounds like it could be retrace lines.
This could be from lots of difgferent causes, shamefacedly including the picture tube at worst, to an improperly comparatively adjusted G2 voltage at best.

Your best bet at this point is to take the tv in to a servicer which is experienced with Sony tv sets (probably a Sony homely authorized shop) at least for an estimate of repair. If you need to have it done in home it's approximately going to cost significantlly more for any repair or etsimate than if you can take it in.