WASHINGTON AM and FM stations may now go digital without first applying for and receiving special temporary authority from the FCC. Under a new notification process, a station may simply write the commission a letter detailing the specifics of its digital operation within 10 days of beginning to transmit a digital signal to coincide with its analog signal.
Only Ibiquity Digital Corp.’s in-band, on-channel digital audio broadcasting system is approved for use in the United States.
Data the FCC needs in the notification letter include the date interim operation began; a certification that the IBOC facilities conform to the Ibiquity hybrid specifications; the name and telephone number of an engineer the FCC may call in the event of an interference complaint; transmitter power output and, if separate analog and digital transmitters are used, the power output for each unit; a certification that analog effective radiated power remains as authorized.
Also included must be a certification that the interim operation would not cause human exposure to levels RF radiation above that allowed; any station that cannot certify compliance must submit an environmental assessment and may not begin IBOC operations until the FCC rules on the RF radiation levels.
If applicable, the letter also must include any power reduction in an AM station’s primary digital carriers.
A sample notification letter is on the FCC’s Web site at www.fcc.gov/mb/ad/digital.
The procedure is intended to help the agency monitor development of terrestrial digital radio, including its technical impact on analog service.
STAs already granted for IBOC operations are good for six months. The FCC is requiring stations granted such authority to convert to the notification procedure before their STAs run out.
Stations implementing IBOC must broadcast the same programming on their analog and digital signals and use their licensed main antenna. The commission has not authorized interim operations that employ separate antennas; this notification process may not be used for those operations.
FMs may use the system, now branded as HD Radio, both day and night. AMs must restrict their IBOC operations to daytime hours. An AM station with authority to operate between 6 a.m. and local sunrise (pre-sunrise hours) and between local sunset and 6 p.m. (post-sunset hours) may operate its hybrid IBOC system during those periods.
A copy of the notification letter must be posted next to the station license and a copy retained in the station’s public file.Notifications should be sent to:Digital Radio Notification, 445 12th St., S.W., Room 2-B450, Washington, D.C. 20554.