Assertion: large directional antenna | /r/ObjectUse | used for broadcasting
Facets:
value: in the mf
type: LOCATION
value: in lf
type: LOCATION
value: in vlf bands
type: LOCATION
Source sentences:
text: The ground waves used for broadcasting at low frequencies must be vertically polarized, so large vertical monopole antennas are used for broadcasting in the MF, LF, and VLF bands.