KCBX

KCBX (90.1 FM) is a non-commercial radio station that is licensed to San Luis Obispo, California. The public radio station is a member station of NPR and airs a wide variety of programming, including "All Things Considered", "Democracy Now!", and jazz and classical music.
KCBX has a network of repeaters and translators that enable the station to be heard throughout the Central Coast of California. Full-power repeaters are KNBX (91.7 FM), licensed to San Ardo, California, and KSBX (89.5 FM) in Santa Barbara, California.
KCBX itself broadcasts in HD Radio.
History.
KCBX first signed on July 27, 1975 and began airing a variety of NPR programming, plus jazz, classical music, and foreign-language shows.
KSBX, a full-power repeater of KCBX in Santa Barbara, began broadcasting April 1, 2003.
From the 1970s through the end of 2012, KCBX broadcast live meetings of the San Luis Obispo County Board of Supervisors. In its decision to drop coverage of meetings, the station cited a lack of interest in the radio broadcast as county residents can stream meetings online.
Repeaters and translators.
KCBX operates two full-power repeater stations: KSBX on 89.5 MHz in Santa Barbara, California and KNBX on 91.7 MHz in Monterey County. The station also operates several low-power FM translators scattered throughout the Central Coast.
KPBS-FM interference problem in Santa Barbara.
In parts of the Santa Barbara area, sometimes during atmospheric ducting, co-channel KPBS-FM in San Diego can override or interfere with the KSBX signal. At one time, KSBX was a 9-watt translator on 89.9 MHz; later, another station began using that translator. Eventually a deal was reached that would vacate that frequency. In 2006, KCBX applied for a Federal Communications Commission (FCC) construction permit to move back to 89.9 MHz and increase the effective radiated power from 50 watts to 350 watts. As part of the application, the station enclosed copies of numerous letters and emails from listeners complaining about the signal override or interference from KPBS. In support of the frequency change, a consulting broadcast engineer was hired to analyze the situation, make signal strength measurements during ducting, and fully explain the technical causes of the problem to the FCC. Making the interference problem worse is the fact that the KPBS signal travels completely over water.
In 2010, KPBS-FM was granted a construction permit to increase its effective radiated power from 2,700 watts to 26,000 watts. The consulting engineer explained to the FCC that if KSBX's frequency change was not granted, this would worsen the interference problem. In February 2012, the FCC dismissed the construction permit application from KCBX. KPBS started broadcasting with the new 26,000 watt signal on October 1, 2012.