Made in Germany
NFA1000_4.6_e.doc as of July 2010
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© Gigahertz Solutions GmbH
The option “Nine Point Measurement” guides the user by means of short audio sig-
nals through the nine points. The PC automatically generates a protocol of the re-
sults. Details of the procedure to follow once this feature has been implemented.
6.2.2 High Frequency Measurement
with HF-Analyser connected
In a high frequency measurement instead of measuring on specified points one
searches for the maximum impact in the sleeping area.
Execution of the HF measurement
Connect the HF-Analyser to the AC input socket.
Double-click the “rec” button to start the measurement and activate the audio
recording. (The meter automatically detects that the AC input socket is active
and selects the HF guided measurement instead of the three point or nine point
measurement as the case may be.).
After 3 seconds and marked by the short beep a measuring period of 30 sec-
onds begins.
In the sleeping area, e.g. within a meter radius, move the HF meter connected in
all directions including upwards and everywhere (the so-called panning method).
Evaluation of the HF measurement
The HF measurements are also listed with the other guided measurements and
evaluated along the same lines as described for the three point measurements.
The maximum exposure during the 30 seconds will be automatically transferred
to the measurement protocol.
For this measurement the audio notes are of specific importance, as the settings
of the HF analyser cannot be detected by the NFA instrument.
6.3 Long term Data Logging
The normal approach in building biology is to record only the magnetic field, and
this as tRMS. Why only the magnetic field? While this is subject to large fluctuations,
as it depends on the actual current, the electrical field is more or less constant, de-
pending on the voltage only
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.
The instrument’s sample rate is 110 000 full data sets per second. The interval for
recording data is set to 10 data sets per second. In between the pre-set intervals for
date recording, it retains the peak values continuously and simultaneously for all
frequencies, axes and the fourth channel and records them on the SD card.
The built in Li-Ion batteries, fully charged, will last for up to 36 hours of continuous
data logging (with the SD-cards supplied with the instrument). In order to extend the
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The recordings of the E-fields above 2 kHz is of interest, though, for the evaluation of dirty power,
i.e. of the high-energy transients. With the NFA, this is even possible against one axis or against earth
parallel to a three-dimensional tRMS recording of the magnetic fields (with the configurable NFAsoft).
