CREATE TABLE table_12379297_1 (coverage__transmitter_site_ VARCHAR(255), callsign VARCHAR(255), station_type VARCHAR(255), power__kw_ VARCHAR(255))
What is the coverage of relay 5kw of dyfj-tv?
    
SQL: SELECT coverage__transmitter_site_ FROM table_12379297_1 WHERE station_type = "Relay" AND power__kw_ = "5kW" AND callsign = "DYFJ-TV"