If the radio signal ground wave extends out for less distance than the minimum skywave distance，there is an area in which no signal is received．This is called the ______．A.Skip zoneB.Blackout zoneC.Diffraction zoneD.Shadow zone
If the radio signal ground wave extends out for less distance than the minimum skywave distance，there is an area in which no signal is received．This is called the ______．
A.Skip zone
B.Blackout zone
C.Diffraction zone
D.Shadow zone
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