We got our mitsubishi in 2000. it was working fine and then little by little the picture has wavy lines and you can't see the movie, it has gotten much worse. what can we do?

You can either yrplace your Hyper board, or replace all the serfice mount capacitors in it. The cap replacement fixes this 90% of the time.

Sounds like the convergence has failed. This video gives more details

Many different mitsubishi's have problems with voltage regulators going out and causing wavy diagonal lines that scroll the picture from top to bottom or vice versa. Without a model number it's difficult to clarify.

Ur tv convergence is dead.U must know how to solders?The 2 STK convergence ICS.and some or all it resistors must change.Tries websites Tv repair World.com,Tvrepairkits.com to repair it ur self.The shop will cost u $300 for parts and labors.

I assume the picture after viewing your "certain movie" you have a snowy type of picture with sound? This is because your "certain movie" will have a bad section or worn section of tape & is making the heads dirty. Is there a part of the "certain movie" that gives wavy lines or the picture breaks up? If a tape is constantly used it causes the oxide coating of the tape to flake & dirty your heads. You could try a head cleaning tape although these sometimes do not do a thorough clean.

A problem like yours is NORMALLY NOT the TV set's fault....it's the Cable.

I'll bet you see thin lines moving across the entire picture...they are slanted like this >> \ \ \ \
That's generally caused by a bad ground on the antenna cable OR it can be the cable box's MODULATOR.

Try using your VIDEO OUTPUT off of your Cable box and see if the wavy lines are still present. If they are the Cable box needs swapped with a good unit.

You can also verify this problem by checking your TV with a DVD player...no lines indicate the TV is fine.

If you have problems with the DVD player's picture, then you must have dried out filtering capacitors on the Video board IN the TV set...

And THAT is not an easy fix if you do see lines with your DVD player.

sounds like convergance ic's mits is also know for bad caps
1000uf @ 16v check for bulges on top of the cap
http://cmpalmer.blogspot.com/2006/11/fixing-my-own-tv-part-ii.html

First do the self test on these threads or goto ctechnicians.com

There is a Hyper Module mounted right behind the video inputs board. in most cases you can replace the 10uf surface mounts carefully not to tear the foil. and the set will return to normal. or replace the H/M board. this board is soldered 4 tabs on bottom of main board and then pulls out. good luck list of caps cz52(may not have this cap).. cx261 cx270 cx230 cx178 c514 cx221 cx250 cx241 cx541 cx670

Elsewhere! Bad hyper board =bad caps on board need replacement = find a different tech who has heard of this repair or
have him research fixya / Toshiba/ 42H81 / hyper board ......T.