Video: 'Grateful Dead Support KMPX Strike! - This Forgotten Day in S.F.'

(Sunday, August 6, 1967) — KMPX of San Francisco became the first radio station in the United States today to take advantage of new FCC regulations and to go to a progressive rock format.

The programming on the 106.9 FM frequency began a trend toward FM radio stations making the transition from “easy-listening” music to “album rock” music.