Assertion: antenna's length | /r/HasProperty | several tens of meters
Facets:
value: typically
type: DEGREE
Source sentences:
text: It's a length of very thin wire (typically several tens of meters) looped anything from a few dozen to a few hundred times around a ferrite (iron-based magnetic) core, which greatly concentrates the magnetic part of the radio signals and produces ("induces") a bigger current in the wire wrapped around them.