It uses a transmission power of 1200 kW .
LORAN - C transmitter Helong is the Yankee secondary of the China North Sea LORAN - C Chain ( GRI 7430 ) .
Helong uses a transmission power of 1200 kW .
LORAN - C transmitter Helong is the Yankee secondary of the China North Sea LORAN - C Chain ( GRI 7430 ) .