The Philco Overnighter

3-way (ooh, er). Presumably AC, DC, and batteries. Was DC household current being used anywhere in the 1950s? With four vacuum tubes, carbon zinc batteries wouldn't last through a thorough makeup application.

Mom had a portable radio from this era and at the time I saw it, it still had those carbon zinc batteries inside it, although the batteries were long dead. If you've never seen those batteries, they were like baseball bats in size, weighed about 18 ounces each and put out a lot of voltage. Something like 24 volts if I remember correctly. The good old days before the transistor was developed.

The direct current reference was probably for hooking it to a car battery in keeping with the portable aspect of the radio. Many cars didn't come equipped with radios at the time. Or record players either, but that's another subject...

The B&W TV I use to watch weather reports aboard my boat is 3-way. It plugs into the boat's 12 volt system. Since it's from the days before even NiCad's, it also can use a bunch of alkaline "C" cells – 8, I guess, to give 12 volts. The battery operation was never useful.