Although 6XC, located in San Francisco, was licenced to Lee De Forest, Incorporated, it was generally referred to as "The California Theater station", which is where its transmitter was located, and where most of its programming originated. In December, 1921 ownership was transferred to the Atlantic-Pacific Radio Supplies Company in Oakland, and its call was changed to KZY. The station was deleted in January, 1923.
San Francisco Chronicle, June 20, 1920, page 8:
Electrical  Home  Visitors  to  Hear  Wireless  Concert

Novel  Programme  Will  Be  Heard  This  Morning  at  11  o'Clock

    A repetition of the epoch-making performance of Madame Melba this week in singing to all Europe by a wireless telephone will be repeated this morning in the Electrical Home, St. Francis Wood, when visitors will hear the orchestral concert of Herman Heller transmitted from the California Theater by radio.
    The concert will begin at 11 o'clock and continue until 12 o'clock.
    The amplification of the musical strains transmitted by the wireless telephone, in order that the music may be heard in all parts of the home, has been made possible through the co-operation of R. M. Klein, president of the Lee de Forest Radio Telephone and Telegraph Company.
    Although a number of minor demonstrations of the possibilities of the wireless telephone have been made in the East, it was not until Madame Melba this week sang to the capitols of the world from the Chelmsford wireless station that the full significance of this invention was revealed to the public.
    In this demonstration the singer's voice was carried over a distance of more than 1000 miles.
    Arrangements have been made to continue between the hours of 2 and 4 the usual musical programme rendered at the California Theater. The home will be open from 10 A. M. until 5 P. M. to the general public.
June 21, 1920, page 4:
Melody  by  Radio  Given  First  Trial

Electrical  Home  Hears  Concert  By  Wireless

    Melody by radio made itself heard in San Francisco for the first time yesterday, when the Sunday morning and afternoon concerts of Herman Heller's orchestra at the California Theater were transmitted by wireless telephone to the Electrical Home in St. Francis Wood.
    Each number on the programme was heard in all parts of the home, which was taxed to its capacity.