Soviet iron is not new, even very, our mothers and grandmothers used such, that's braid at the base and shabby.
Unscrew the screw back cover, remove the cover.
Remember where they had been bolted onto the wire, unscrew them, we clean to a shine, for a device of this age copper wires are usually black.
Then push through the wire in its place through a special elastic band, you can tie a knot, if it fits, but you can like the picture below, the wires connect, fasten them as they were.
Light bulb if it is intact, too, put in place, close the lid and turn the screw. Now the technology is working and can work even 30 years old.