One of my on-again, off-again hobbies is restoring old radios. I thought I'd post a few of them. Here the first: This is a 1949 Bendix 55P3. Bendix manufactured truck parts, mostly brakes, up until WWII. During the war they made radio and navigation equipment for aircraft; after the war ended, they leveraged their reputation to get into consumer products, but it was a short-lived attempt. The circuit is what radio collectors term an "All-American Five" -- it uses five US-made tubes, just about the minimum you can have and still have a radio that performs decently well. This was by far the most common circuit for tube radios because it was by far the cheapest. There is no transformer. The tube filaments are wired in series to add up to 120 volts (including the dial lamp), and 120V AC power from the line is rectified and filtered for the plates. These radios were sometimes called "AC/DC sets" because they would also work on 120V DC. (New York still had some areas with DC power, on the old Edison system, at the time.) One downside of this design is there's no isolation, and on some radios the chassis can be "hot" -- potential widowmakers. They can be rewired to be safer (as this one has been.) Below is the label on the bottom plate, showing the specifications and the tube line-up. Notice the RCA license notice (they had a patent on superheterodyne receivers) and the "Bendix Aviation Corporation" logo at the bottom. The frequency coverage doesn't include the 1620 to 1710 kHz range that modern radios cover -- at the time this was made, that was a police band.