Can't be sure of the exact date KDAY went full-time, but it was somewhere around 1971.
I was weekending while going to UCLA and working afternoons for an early programming consultant, Ted Randal. Art Astor had moved from sales manager at KHJ to the GM chair at daytimer KDAY. Bob Wilson (founder of R&R) had come down from the San Joaquin Valley. They were still running a quasi-Top 40 format.
The 50kw transmitter was near Santa Monica, but in the City of Los Angeles. Studios had moved to 1700 North Alvarado a bit before that, with the six towers already constructed, and a new 50kw xmtr was in place, waiting for the fulltime go-ahead from the Commission.
I was at work at Randal's when I got a call from Bob Wilson. The FCC had just authorized fulltime 50kw from the Alvardo site. Could I come in at 7 pm, to make the transition to night operation. (It happened around 8pm, so it had to be in the summer.) I was playing the soft rock, and at normal night sign-off, I said "KDAY now becomes K-Night."
The 50kw operation from Alvarado did not last long. Tremendous induction into the old PacBell Normandy exchange office. FCC got involved. KDAY then had to go back to the "Santa Monica" site for daytime 50kw operation, with nights coming from the Alvarado site at 10kw.
Ultimately, Rollins decided the two xmtr site operation was not financially viable, so the 50kw "Santa Monica" xmtr was shut down, and all transmission was moved to Alvarado at 10kw. For what seemed an eternity, with apparently Rollins footing the bill, shielding was accomplished by the phone company at their CO, and we were able to return to 50kw.
Art and Bob then introduced what would become a very formatted "AOR." which did very well for a while until fm--primarily KLOS at that point--began to gain an audience, and pushed KDA's numbers down, down, down.
With the new format and full power, Art and Bob convinced me to leave Randal's and take the morning drive run at KDAY.
Many tales about that version of KDAY. My first newsman in the morning was Steve Fredericks, who had done a lot of cartoon storylines for Playboy. When Steve left, he was followed by the brilliant Loui Irwin. Nathan Roberts did mid-days. He eventually landed at Channel 2, doing news -- eventually ending up in Washington DC. Sam Riddle did afternoons before segueing to television production ("Star Search," etc.) B. Bailey Brown was the night-time time jock. Several jocks held down the overnight, including the ubiquitous John Darin.
Eventually, Wolfman came on board. Until he got the gig in New York on NBC's midnight special, he did his 7pm-Midnight gig live from Alvarado. (Lots of tales to be told about that era, but I shall demur until i write my autobiography!) When he moved to the Big Apple, he did his show on tape for KDAY.
We did very well for a while, until the aforementioned discovery of fm by the audience led to a significant slip in Arbitron.
Meanwhile, Rollins was moving its properties into the "R&B" format. As the numbers slipped at KDAY, corporate in Atlanta decided it was time to change the format. The staff was called into the conference room where a suit from the home office explained the format change and reassured the troops that most of their jobs were secure.
(I was offered the PD's job at their Wilmington, Delaware property. No thanks! LA for me!
Leaving that meeting, the suit walked down the hall with me to my office. From his inner jacket pocket, he pulled out a folded piece of paper, handed it to me, and said "Fire these bast*rds." Less than five minutes after telling the staff most jobs were safe, he gave me a list of more than thirty people who were out of a job by the end of that day.
His explanation to me for the change: In his southern drawl, he said "We know how to make money with this nig*er format!"
Enough said.