KDIA (1640 kHz) is a commercial AM radio station licensed to Vallejo, California, and serving the San Francisco Bay Area.
[4] Taking advantage of this provision, on March 19, 1996, KXBT (now KDYA), 1190 AM in Vallejo, began to also broadcast on 1640 kHz,[5] as the second U.S. station, following WJDM in Elizabeth, New Jersey, authorized to operate on an expanded band frequency.
On March 22, 1996, the FCC issued an updated list of expanded band allotments, which now assigned KXBT to 1630 kHz, so transmissions were switched to that frequency.
[6] On March 17, 1997, the FCC released a final revised roster of eighty-eight expanded band assignments, with KXBT designated to move back to 1640 kHz.
One restriction is that the FCC has generally required paired original and expanded band stations to remain under common ownership.
Use of the KDIA call sign had a prior history in the San Francisco Bay area, and was most recently used on 1310 AM by a station that began broadcasting as KLS in 1922.
For four months in 1984-85 the station was owned by Adam Clayton Powell III, during which time it carried the call letters KFYI and broadcast an all-news format.
In 1992, Oakland journalist Chauncey Bailey returned to the Bay Area to work as public affairs director and newscaster on KDIA.