A.≥500m B.≥1000m C.≥2000m D.≥2500m
A.450KHzVHF~470KHzUHF B.450KHzVHF~470KHzVHF C.420KHzVHF~450KHzVHF D.420KHzVHF~450KHzUHF
A.100W B.200W C.250W D.300W