KENDRAPARA: The Orissa State Disaster Mitigation Authority (OSDMA) installed 21 ham (amateur) radios in ten districts, including six coastal ones, recently. Last year, UNDP provided the ham radios to OSDMA for installation. Due to non-availability of trained ham radio operators the installation of radios was delayed, said Pravat Ranjan Mohapatra, deputy general manager and coordinator of OSDMA.