In the early 1990s the AMAX certification program, covering radio broadcasting standards, was  developed in the United States by the Electronic Industries Association and National Association of Broadcasters.This logo, including the word "stereo" if the receiver was capable of stereo reception, could be placed on radio receivers that met the AMAX standards.
Unlisted
Image included in the article "Reinventing the AM Radio", which appeared on page 27 of the Radio section of the August 19, 1991 issue of Broadcasting magazine.