Sec. 74.603  Sound channels.

    (a) The frequencies listed in Sec. 74.602(a) may be used for the 
simultaneous transmission of the picture and sound portions of TV 
broadcast programs and for cue and order circuits, either by means of 
multiplexing or by the use of a separate transmitter within the same 
channel. When multiplexing of a TV STL station is contemplated, 
consideration should be given to the requirements of Sec. 73.687 of this 
Chapter regarding the overall system performance requirements. 
Applications for new TV pickup, TV STL, TV relay and TV translator relay 
stations shall clearly indicate the nature of any mutliplexing proposed. 
Multiplexing equipment may be installed on licensed equipment without 
authority of the FCC, provided the installation of such apparatus on a

[[Page 415]]

TV STL station shall not result in degradation of the overall system 
performance of the TV broadcast station below that permitted by 
Sec. 73.687 of this chapter.
    (b) The aural portion of television broadcast program material may 
be transmitted over an aural broadcast STL or intercity relay station 
licensed under the provisions of Subpart E of this part, but only on a 
secondary, non-interference basis to the programming of aural broadcast 
stations. A TV station licensee may continue such operation until the 
channel assigned to its Subpart E station is requested by an aural 
broadcast licensee after a showing that no other vacant channels are 
available or satisfactory. Upon Commission concurrence with the aural 
broadcast licensee request, the TV station licensee will be required to 
discontinue operation on the requested frequency. In areas where only a 
portion of the Subpart E frequencies used by TV station licensees are 
required by aural broadcast licensees, the Commission will assist all 
affected parties in arriving at an equitable solution. The provisions of 
this paragraph do not preclude continued use of Subpart E facilities for 
relay of TV sound where the facilities are authorized to an aural 
broadcast licensee and the primary purpose of the station is to relay 
aural broadcast programming.
    (c) Aural STL or intercity relay stations licensed as of July 10, 
1970, to operate in the frequency band 942-947 MHz, may continue to so 
operate pending a decision as to their disposition through a future rule 
making proceeding.
    (d) Remote pickup broadcast stations may be used in conjunction with 
television pickup stations for the transmission of the aural portion of 
television programs or events that occur outside a television studio and 
for the transmission of cues, orders, and other related communications 
necessary thereto. The rules governing remote pickup broadcast stations 
are contained in Subpart D of this part.

[ 28 FR 13718 , Dec. 14, 1963, as amended at  47 FR 55936 , Dec. 14, 1982; 
 48 FR 24385 , June 1, 1983]