Geometrics G-822A, Руководство по эксплуатации

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Geometrics, Inc. G-822/G-823 Magnetometer Manual
4
Like all magnetometers, performance of the G-822A is primarily dependent upon the
counting circuitry employed and the quality of the installation procedures. Compensation
and/or noise reduction techniques must normally be used to minimize the magnetic effect
of the platform and its motion. Navigational and positional errors, radiated
electromagnetic noise and heading errors from the aircraft's induced and remnant
magnetic fields are typically the major contributors to noise in the survey results.
4.0 INSTALLATION
The particular installation requirements for each system component must be met in order
to obtain the best performance from the system. It is important to remember that the
sensor driver circuit receives a signal from the sensor whose amplitude is normally one
milli-volt as it delivers both heater and lamp oscillator power to the sensor. Anything that
increases the cross-talk between the power and signal circuits or introduces noise into the
power circuit can degrade the sensor output signal and affect system performance. A
BNC terminated coaxial cable is used to supply power to the matching connector on the
G-822A sensor driver module.
Figure 4
. Surface inclination of the earth’s magnetic field.
Epoch 2000, 2º contour interval.