TV has audio sound and no picture

get kit 61-121 $7.95 and don't forget to solder the horizontal drive transformer, bet this has ring fractures and thats what kill these sets

deffective tube crt socket problem

Your set migbe missing the high voltage that lights up the picture tube,you need to check for loose conections starting at the horizontal drive transistor and transformer ,then check the horizontal output transistor for short,it needs to be checked with a meter if the output is shorted it probably open a safey fuse or resistor to prevent more damage.If you are familiar with tv service this will give a place to star but if you are not too familiar be safe and seek the help of a servicer.Let Us know if you need more information.

The previous replies by techman and jomaru are probably the correct proceedure, but have you tried increasing the brightness and contrast to maximum ( this may be impossible with the on screen menu).
Is there any static on the screen, if so the line time base and transformer would be OK. If you have good hearing, and no tinatus problems you should be able to hear a very high pitched whistle from the line timebase