ETS-Lindgren HI-3604, User Manual

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The HI-3604 can be user programmed to indicate in either units of
milligauss/gauss, milliamperes/amperes per meter, or nano/micro
teslas. The HI-3604 indicates magnetic field flux density in units of
milligauss (mG) and gauss (G). The SI unit of magnetic field flux
density is the tesla (T). Environmental ELF magnetic field
measurements are generally reported in units of microtesla (μT) or
nanotesla (nT).
Magnetic field measurements in free space may be converted to
different units through the following relations:

1.0 mG = 0.1 µT = 80 mA/m

10 mG = 1.0 µT = 800 mA/m

100 mG = 10 µT = 8 A/m

1 G = 100 µT = 80 A/m

10 G = 1 mT = 800 A/m
The figures that follow illustrate typical frequency response plots for
electric and magnetic field strength. The HI-3604 is designed to
provide a flat response over the range of frequencies corresponding to
the 50 or 60-Hz power line frequency and the first several harmonics.
The tailored low- frequency characteristic to the response helps reduce
magnetic field response to movement of the sensor in the earth's
constant magnetic field. The bandwidth of the true RMS detector is a
function of the amplitude of the applied field. The bandwidth of the HI-
3604 is also related to the particular measurement range selected.
Thus, for a specific measurement, the bandwidth exhibited may be
greater or lesser than shown in in the figures. Generally, maximum
bandwidth, and thus accuracy, is obtained for any given field strength
by selecting the lowest range (and scale) that still permits an on-scale
reading. The HI-3604 also provides for monitoring the waveform of the
signal coming from the sensor preamplifier circuit in the input module.