No picture...Sound is fine.

Do you have a multimeter and able to pull the back off and get some voltage readings?

Vertical scan output section circuit should be checked. Contact any service technician.

Fault with the main power supply regulator board. Check and replace damaged component/s at its main power regulator [SMPS] section circuit. Contact any service technician. If you wish to get some details; check the site linked here. Surf the site with patience. Pull up older posts.
http://electronicshelponline.blogspot.com/

cold solder in vertical ic and check caps around to..if you see resin around any cap, change.

what you suggesting is that the lcd has a good maintenance needs that have to have cold solder or connectors are sulfated

take to a service station i think just changing the displsy IC would do . but check in service centre

Did you mean the picture is collapsed only in the middle horizontally(white line appears on the middle part of the screen)?
If that is the case, maybe vertical IC failed or loose connection.

Three guns Red Blue and Green in the picture tube of an old CRT set. If one of the guns goes out it effects that color. Sounds like one of the guns inside of the tube is going out, To costly to replace for such an old antilog set that will have to have a convertor box next month anyway.

Could be a horizontal output fault, faulty power supply, a simple dry solder joint or HVT. If you can hear arcing or smell an ozone odour, it will be the HVT which may cost a bit.

Without knowing the actual cause, it's impossible to say how much it would cost to fix it.... could be anywhere from $50 to $250 etc

Best to have it checked by a technician and get a quote to repair... then decide if you think it's worth it.

Toshiba is generally a reliable brand, so if you were happy with the picture quality before the fault occurred, it's probably worth repairing.

Cheers

The good thing is you see something in the screen,with age the set has developed loose conections in a few different places,my suggesion is to call professional for service now and the repair will not as expensive,if the picture quality is good is worth it.