ETS-Lindgren HI-3804 RF Industrial Compliance Meter - Manual (Page 21)

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For accurate readings, follow these guidelines:
 The arm holding the probe should extend away from your body as far
as possible without becoming uncomfortable, and the probe should
point towards the energy source.
 Measurements in the electric field from low frequency antenna systems
often require special techniques because the human body acts as a
scatterer and introduces errors. The best technique to use when
making measurements near antenna systems is to place the probe
next to the readout on a non-metallic stand such as a wooden ladder
or cardboard box. Then stand back and read it without touching it.
Note: The human body does not greatly affect magnetic fields. The
techniques described previously are more critical for electric fields.
 Scan the probe through the field to obtain a maximum reading.
 The protective cover on the probe should not be closer than
four inches (10 cm) to the surface of the energy source; otherwise, the
readings may be inaccurate.
Z EROING
When the readout sends a zero command, the probe must be in a zero field
environment. This is because the zero command causes the multiplexer (through
the processor) to perform a normal read cycle on all axis signals. This is
executed for all three ranges, both E and H fields. When the processor receives
all the zero-field signal values, it stores them in a special register; the values are
subtracted from all subsequent measurements. Therefore, a probe which is
zeroed when not in a zero field environment will give erroneous readings.
Turn the readout on. A few seconds after you turn the system on it is ready for
operation (measurement). The LCD displays the observed value and the units of
measure.
The bar graph displayed on the LCD represents an analog approximation of the
measured field. Each bar graph segment represents 5% of the full scale reading
in the current range. The bar graph is updated 7.6 times per second and the
digital display is updated 1.9 times per second.