How could I make an old TV material? I've tried some nodes, but I don't get the dessired result
In Node Editor add Subsurface Scattering shader set Radius to 1.5 to have nice darkened corners, select desired color (for example #CCE7D7) then add Glossy shader and set Roughness to 0. Add Mix shader, connect them and as a factor add Input > Fresnel to fake PBR reflections.
Now you will have something like this:
To add this white spot in the center of the screen we will need Gradient Texture as color for Subsurface Scattering. We will also need some simple UV unwrap for the screen, mine is simple Project from view (bounds) from Front Ortho view.
Add Input > Texture Coordinates then Vector > Mapping, now in Mapping node choose Texture tab and set Scale to 0.7 (X, Y, Z) and Location to 0.5 (X, Y). Those values may vary based on your mesh/unwrap!
Now add Texture > Gradient, set it to Spherical, add Converter > Color Ramp, change black color to the one from base material steps and move white color to the left (more to the left, bigger white spot).
Connect it to the Subsurface Scaterring color slot and we are done here.
Note that I'm using Environment Texture for lightning and reflections. You will have it packed in .blend file.
I tought that I can crank it up a little bit by adding this white spot in the center of the screen. More details above, I think that extending previous steps would be much better then creating it belowe edit.