Advertisement
Available languages
Available languages
instrument rather than twisting the cable. The LED at the front of
the antenna indicates a good connection, which is essential for an
accurate measurement!
Remarks concerning the antenna
The "semi rigid" cable has the best technical parameters in the instrument's
frequency range. It is designed for several hundred changes of orientation with-
out effects for the accuracy of the measurement. For the special design of the
second connecting cable we have a patent pending. The objective is to reduce
an inherent weakness of "simple-log.per" antenna designs made of PCB materi-
al. For radiation incoming at an angle to the main direction normal designs pick
up signals also below the design frequency range, which can falsify the meas-
urement. This antenna suppresses this by 15 to 20 dB in addition to the approx.
40 dB of the high pass filter.
Settings of the Analyser
At first set "Range" to "1999 µW/m²". Only if there are constantly
very small readings, switch to the finer range. The basic rule is:
as coarse as necessary, as fine as possible. In the rare case of
power densities beyond the designed range of the analyser ("1"
displayed on the left hand side even in the coarsest range) they
can still be measured by inserting the attenuator DG20_G10,
available as an optional accessory, which makes the instrument
less sensitive (by a factor of 100).
Setting Signal Evaluation ("Signal"): The peak HF radiation val-
ue, not the average value, is regarded as the measurement of
critical "biological effects" affecting the organism and to be com-
pared to recommended safety limits.
The average value ("RMS") of pulsed signals is often only a very
small fraction of the peak value. Nontheless it forms the basis of
most of the "official" safety limits regulations. Building biologists
consider this a trivialization.
How to execute the measurements
Hold the HF analyzer with a slightly outstretched arm, your hand
at the rear of the instrument.
For a rough first overview it is sufficient to probe for areas of
higher levels of radiation simply by following the audio signals
walking through the rooms of interest, directing the analyser eve-
rywhere and rotating it.
Having identified the area of interest for a closer evaluation,
change the positioning of the instrument in order to analyse the
actual power flux density. This is done
by pointing in all directions including upwards and down-
-
wards in flats to establish the main direction of the incoming ra-
diation,
by rotating the instrument around its longitudinal axis by
-
up to 90
to also find the plane of polarisation, and
°
by shifting the instrument in order to find the point of
-
maximum exposure and to avoid being trapped by local cancel-
lation effects.
© Gigahertz Solutions GmbH
Made in Germany
11
Advertisement
