Running a Delco R-1235 "AC/DC" Radio on Batteries

In the early days of electrical distribution within the United States, a number of different generation and distribution standards emerged. As such, a lot of early radio and TV manufacturers produced equipment that could operate on alternating (AC) or direct (DC) current. These devices are variously referred to as "series string", "AC/DC", "transformerless" or "hot chassis" sets. Some appliances also have universal motors that can operate on AC at varying frequencies or DC, such as the Hoover Constellation