A leading ham group has come forward to protest the test plans of Digital Aurora Radio Technologies, the company that has an experimental authorization to test Digital Radio Mondiale broadcasts at high latitudes.
The national association for amateur radio, the American Radio Relay League, says one of the frequencies on which DART would test will interfere with amateur broadcasts, and the ARRL has asked the Federal Communications Commission to modify or cancel the experimental license. But the company tells RW it won’t operate in those frequencies. The FCC amended the license.
In 2009, DART proposes to test statewide transmission of DRM at high latitudes in the 5, 7 and 9 MHz shortwave bands; it hopes the tests, if successful, will lead to a terrestrial, high-frequency digital radio service for the state of Alaska.
The ARRL takes issue with testing on the 7.1 – 7.3 MHz portion of the band, which it says is heavily used within ITU Region 2, including Alaska, and “is allocated domestically exclusively to the amateur radio service.” DART plans to test using a 20 kHz bandwidth digital emission at a transmitter output power of 100 kilowatts and an ERP of 600 kW within a radius of about 930 miles of Delta Junction, Alaska.
“There is a 100% certainty of severe, continuous, harmful interference from operation of the DART facilities as authorized by the commission to ongoing amateur radio operation at 7.1 to 7.3 MHz,” says the ARRL in its petition, filed this week. It calls that portion of the 7 MHz band perhaps the most heavily used amateur HF band in the United States.
According to the grant for the CP and license, issued Oct. 7, operation is subject to prior frequency coordination with the SBE. On Oct. 24, the FCC issued an amended license that redefined one of the station’s frequency ranges to eliminate conflict with the Amateur Radio Service. The amended license narrows the range to 7.30 to 7.60 MHz.
In response to queries Thursday evening from Radio World asking about this issue, company President Whit Hicks stated in an e-mail that DART would not operate in 7.1 to 7.3 MHz, to avoid any interference with amateur operators.