That site has been the transmitter for 1110 AM for years. Back in the 80's, it was also home to KPOP prior to their move to Madison Avenue. The building was renovated in the mid-80's to upgrade the KRCX plant, at the same time as the KPOP studio buildout at 5301 Madison. KRCX-AM studios stayed on-site until Arthur Liu bought the station (I believe). Radio Disney used it as a local sales office, but I am not sure if that is the case, since it is behind fences (and still CBS property I think...they have the signage, for now). The middle tower was increased in height in the early 90's to house 93.7's 25,000 watts upon their move from 93.5. (Interesting that the descendant of KPOP has come full circle back to the site where their studios used to be). Michael Rivers Kramer can correct my discrepancies regarding dates, etc.