Radio Service Bulletin (United States Department of Commerce, Radio Division)
 
GENERAL   ORDERS   OF   THE   FEDERAL   RADIO   COMMISSION
August 31, 1928, pages 9-10:
 
    Allocation of channels in the broadcast band to the different zones a separation of 10 kilocycles to be maintained, etc. (General Order No. 40, August 30, 1928)--The commission has determined that the definite assignment of a band of frequencies for broadcasting, the maintenance of a separation of 10 kilocycles between frequencies used in broadcasting, the reservation of certain frequencies for exclusive use by stations in the Dominion of Canada, and the setting aside of a certain number of other frequencies for shared use by the United States and the Dominion of Canada, all as hereinafter specified in this order, will serve public interest, convenience, or necessity.
    It is therefore ordered:
    Par. 4. That the frequencies within said broadcast band (subject to the foregoing) and periods of time for operation and station power to be used by broadcasting stations on said frequencies be, and the same are hereby, allocated equally to the zones, as follows:
    A. The following frequencies are allocated to the first, second, third, fourth, and fifth zones, respectively, as below indicated for use by broadcasting stations, the amount of power to be used by such stations to be determined by further order of the commission: First zone, 660, 710, 760, 860, 990, 1,060, 1,100, and 1,150 kilocycles; second zones, 700, 750, 820, 930, 1,020, 1,070, 1,110, and 1,170 kilocycles; third zone, 650, 740, 800, 850, 1,040, 1,080, 1,140 and 1,190 kilocycles; fourth zone, 670, 720, 770, 810, 870, 1,000, 1,090, and 1,100 kilocycles; fifth zone, 640, 680, 790, 830, 970, 1,050, 1,130 and 1,180 kilocycles.
September 29, 1928, pages 15-16:
 
    Chain programs allowed for only one hour unless stations are 300 miles apart or operate on same frequency (General Order No. 43, September 8, 1928).--It is ordered that until further order of the commission no two or more of the broadcasting stations assigned to the frequencies allocated under subpargraph A of paragraph 4 of General Order No. 40 shall, during the period beginning with November 11, 1928, broadcast simultaneously the same identical program for more than one hour daily during the hours between 7 o'clock p. m. and 12 o'clock midnight, local standard time at the location of the station farthest east, unless (a) the transmitters of such stations are separated by a distance in excess of three hundred (300) miles, or (b) such stations are operating on the same frequency, or (c) such stations receive special permission from the commission. This permission will be granted only in the case of programs of extraordinary national interest or of a nature such that public interest, convenience, or necessity would clearly be served by their duplication to a greater extent than is permitted by the foregoing provisions of this order.
October 31, 1928, page 14:
 
    Postponement of effective date limiting duplication (chain programs) on cleared channels (General Order No. 46, October 5, 1928).--In order to determine the actual extent of duplication of chain programs on cleared channels, under the reallocation of broadcasting stations, effective November 11, 1928, and in order that practical experience obtained may indicate the most practical regulatory measures to reduce such duplication, the Federal Radio Commission hereby postpones the effective date of General Order No. 43, limiting duplicated operation on cleared channels to stations more than 300 miles apart, until the end of the next broadcasting license period, January 31, 1929.
January 31, 1929, page 11:
 
    Postponement of regulation governing chain programs (General Order No. 57, January 18, 1929).--The Federal Radio Commission hereby postpones the effective date of General Order No. 43, limiting duplicated operation on cleared channels to stations more than 300 miles apart, until March 1, 1929.
February 28, 1929, page 14:
 
    Postponement of General Order No. 43, limiting chain programs (General Order No. 59, February 16, 1929).--The Federal Radio Commission hereby further postpones the effective date of General Order No. 43, limiting duplicated operation on cleared channels to stations more than 300 miles apart, 90 days, until June 1, 1929.
May 31, 1929, page 15:
 
    Postponement of General Order No. 43, limiting chain programs (General Order No. 63, May 15, 1929.)--The Federal Radio Commission hereby postpones the effective date of General Order No. 43, limiting duplicated operation on cleared channels to stations more than 300 miles apart, 122 days to October 1, 1929.
September 30, 1929, page 10:
 
    Postponement of General Order No. 43 regulating chain programs (General Order No. 71, September 18, 1929).--The commission hereby further postpones the effective date of General Order No. 43, limiting duplicated operation on cleared channels to stations more than 300 miles apart, 90 days, to December 31, 1929.
December 31 1929, page 12:
 
    General Orders Nos. 43 and 46, limiting chain programs to certain stations repealed (General Order No. 81, December 20, 1929).--In order to assure the uninterrupted broadcasting of high-class chain programs for the benefit of the general public; in order to afford adequate time to the Federal Radio Commission and full opportunity to investigate and determine whether chain programs are being unnecessarily duplicated, and to enable said commission to determine what progress has been and is being made toward the successful operation of two or more stations on the same frequency in synchronism, either by wire connection or otherwise; to afford the Federal Radio Commission opportunity to determine whether chain broadcasting may be successfully carried on in the future with a more economic use of frequencies than now employed, it is
    Ordered, That General Order No. 43 of the Federal Radio Commission, adopted at a meeting of said commission on September 8, 1928, which had as its purpose the regulation of chain broadcasting and placed definite limitations on stations which might engage in chain broadcasting, and General Order No. 46 of the Federal Radio Commission, adopted by said commission on October 5, 1928 as an amendment to General Order No. 43 aforesaid, be and said General Orders Nos. 43 and 46 of the Federal Radio Commission are hereby rescinded and repealed.