I'll mention in passing on the tuning condenser most sets the outside plates will have cuts in them. That's so you can vary a small amount capacitance over a small part or the dial. On the Silvertone it doesn't matter much but if dial had a lot of divisions you would use theses split plates to adjust the tracking (set the tuning across the whole dial and all the stations in the right places.)
The R-390A is a big old BA military receiver circa 1953-early 1980's. Lots of filters, audio and IF, Mechanical digital dial, Very accurate, and sensitive. Some say it's the best of the tube type receiver ever made. They use a bunch of tubes like 20+ and weigh close to 100 pounds. I've got 2.
http://www.r-390a.net/
Terry