Schonstedt SPOT, Instruction Manual

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Introduction
SPOT, a magnetic locator, detects the magnetic field of ferromagnetic objects. It responds to
the difference in the magnetic field between two sensors that are spaced approximately 20
inches apart. This difference is referred to as the “signal strength” throughout this manual
and is represented in the instrument by an audio tone that changes its frequency to help you
pinpoint a target and determine its orientation.
Figure 1 illustrates SPOT detecting an iron marker that is used for property line identification.
As shown, the magnetic field of the iron marker is stronger at sensor A than it is at sensor B.
This creates a signal strength that is larger than zero (which would occur when the field
strength is the same at both sensors).
The audio response of SPOT is designed so that the frequency of the audio tone increases
as the detected signal strength increases. As a result, the frequency of the audio output is
higher than the idling frequency (~ 30 Hz), which exists when the signal strength is
approximately zero.
Following in the steps of Schonstedt’s iconic magnetic locator, the GA-52Cx, SPOT retains
the “yellow stick” look, the sturdiness of the Aluminum tube and the exact same performance
(including the same 5 gain settings). However, SPOT adds modern ergonomics and
functionality, plus improved environmental performance.
Figure 1: Detecting the Magnetic Field of an Iron Marker