Apparently it would only receive one frequency (presumably tuned when made). The target was for developing countries that might have only a single state-run station.
"The radio is, of course, non-directional. This means that it receives all stations simultaneously. But in emerging countries, this is of no importance: only one broadcast (carried by relay towers 50 miles apart) is carried."
Design for the Real World: Human Ecology and Social Change ©1971 pg. 162 https://archive.org/details/designforrealwor0000papa/page/16...