I don't know of the exact switchover date, but Solid Gold did replace Hitparade. Me thinks it was early in '71 or late '70 because as an avid listener I never did hear what the Hitparade '71 jingles sounded like. The Solid Gold jingle "Solid Gold Rock and Roll" was sung similarly to Hit-par-ade se-ven-ty.")
After Solid Gold was another format from another company, but I did not know who it was. It still sounded automated and even program director Jack Kelly had a shift.
Of course, you know, that from mid-1968 to late April of 1969, the station played middle of the road instrumentals only. The NBC Radio Network and the Arizona Broadcasting System programming were broadcast over the air and fed statewide via microwave.
A Schaefer ad wrote of the decision by management to make the FM a profit making station and put the network feeds back on telephone lines to stations around the state. Hence the need for the automation unit and Drake Chenault programming.