Why would any TV manufacturer design their sets to operate on DC power?
Almost all home electric service in the US and probably Canada is 115 volts, 60 Hz AC. I can understand designing TVs to operate on 50 Hz AC current, but AC or DC? DC power would almost certainly destroy the power supply in an instant.
The only thing I can figure is Emerson must have meant the set was transformerless. I cannot believe, however, that this set could also operate on batteries--the only other explanation I can come up with for any kind of "AC/DC" designation for a tube-powered television. The tubes would eat up batteries in minutes, if not seconds.