I've got his
location approximately, but in the neighborhood where he should be
I haven't been able to locate any antennae to indicate the presence
of a radio station. Usually it's easy enough, but this fellow seems
to be a sly fox."
"How in the world do you locate an unauthorized station, anyway?"
queried Bob.
"In each district in which there is a radio inspector we have what
we call directional finders. These consist of a combination of a loop
aerial and a compass and a radio receiving set. We have complete maps
of the district. When the man we're after is sending, we swing the
loop aerial around until the signals reach their loudest tone. Then
a reading is taken on the compass. This action is repeated several
times, after which we turn the loop so as to tune out all sound.
During the silent period a line is drawn on the map at right angles
to the direction of the loop. This line indicates the direction from
which the sounds are coming. This takes place at the same time at all
three stations, and where the lines on the map intersect is the point
where the offender can be found."
"But I suppose that location isn't very exact, is it?" asked Bob.
"No; but it's usually exact enough," said Brandon. "We go to the place
indicated on the map, and look about in the neighborhood for aerials.
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