No picture just sound

soundslike you need a new TV or get this one repaired .

the picture getting darker means the lamp has aged and u need to replace it another thing u need ti replace the mirrors in the light tunnel of the light engine they have faded secondly the noise means the colour wheel has aged you need to replace it u will have to replace the whole light engine cos the color wheel comes inbuilt the light engine and u will be ok ontact lg dealer in your area

Back - light problem. Check and replace damaged component/s at its back-light inverter board, or replace this board as card basis. If you wish to get some details; check the site linked here. Surf the site with patience. Pull up older posts. It will be best to replace the inverter board as card basis.
http://electronicshelponline.blogspot.com/
To some model sets; especially LED back-lighted types; the back-light inverter circuit will be part of the main power supply board [SMPS]. In such cases, the power supply board might need replacement. To some models sets, the back-light inverter and SMPS section circuit will be integrated at its main board itself. If so; the main board should be replaced. To some models of sets, all these section circuit will be integrated at its main board. If this is the case, you have to replace the main board.

Loss of backlight on an LCD television will give you this type of symptom. Since the picture fades slowly, there's a good chance you may have a cold solder connection in the power supply going to the inverter PCB. Cost of the repair from a service center should be from $120-200

Bill W
integrityhomeworx.com

You need to replace backlight inverter.

Thanks

Try lowering the brightness and contrast. Sounds like you are overdriving the picture tube. Green gun in picture tube may have a shorting element; if so no fix for that other than pic tube replacement.

Stacy,

Sounds to me like there is bad solder somewhere on the filament supply circuit. Do you know what a cold solder joint looks like? It is a solder joint that is not making a good mechanical or electrical connection. When you lose that connection the filament inside the tube slowly stops heating the electron guns and the picture will fade away. When the connection comes back the video will come back.

Might be worth it to take the back off and check out the little board that is connected to the end of the tube. The problem is either there or on the power supply.

Shouldn't be a problem for a repair tech. I would not spend very much money though.

YES, THE CRTS WILL START SHOWING THEIR SIGNS OF WEAR. TO REPLACE THEM IS MORE THAN YOU PAID FOR THE SET.

sounds like light engine problems

It seems your set has a loose conection in the high voltage circuits,in fact by now it should have many loose conections in different areas like the power supply and the horizontal deflection circuits,if you are familiar with tv service you can use the information as the first step to take,some of the loose conections are hard to see even for the trained technician but the one giving you this problem should not be hard to see,if you are not too familiar with tv service be safe and call for assistance from a servicer a least for an estimate.