The FCC on January 26 this year authorized KBRT (AM) to move from Santa Catalina Island to Sierra Peak between Irvine and Corona, and increase its daytime power to 50kW directional. With KFMB-AM San Diego on 760kHz and KBRT Avalon on 740kHz, the two stations have had interference issues since 1962 when the FCC gave KBRT the class D daytime-only allocation. The two are unusually close-spaced in both frequency and geography. But the matter heated up in 2007 when KBRT began broadcasting Ibiquity digital sidebands, essentially wiping out coverage of KFMB-AM north of San Diego.
The FCC said KBRT owner Kiertron must continue to operate its AM IBOC channel upper sideband at -29dB from Ibiquity standard levels of -28dBc (28dB below carrier), as it had volunteered in March of 2010 to do. The new day and night pattern gives KBRT a major lobe south-southwest toward south coastal Orange County and moderate nulls northwest toward co-channel KCBS in San Francisco and southeast toward San Diego. The FCC gave KBRT a low nighttime power that it will continue to maintain.
In correspondence filed with the FCC in 2008, KBRT owner Kiertron did not deny the interference it was causing, but claimed that KFMB had no protection of its signal outside of the San Diego metropolitan area due to the wording of the original KBRT authorization to broadcast in 1962.
According to the terms of their FCC Construction Permit, KBRT has until January 2015 to complete their move to the mainland.