Gigahertz Solutions HF58B Instruction Manual page 10

Digital High Frequency Analyser HF58B
for radar signal analysis. When set to "Peak
Hold", they will display the full peak value of
the radar beam after the first beam passing.
This is true for most types of radar.
Please note that there are Radar systems
that are operated at even higher frequencies
that can be measured with this instrument,
yet possibly not the full intensity.
© Gigahertz Solutions GmbH, 90579 Langenzenn, Germany
Quantitative Measurement:
Identify where the radiation enters a struc-
ture
As a first step eliminate sources from within
the same room (e.g. cordless phones, wire-
less routers, etc.) Once this is completed, the
remaining radiation will originate from out-
side. For remedial shielding it is important to
identify those areas of all walls (including
doors, windows and window frames!), ceiling
and floor, which are penetrated by the radia-
tion. To do this one should not stand in the
centre of the room, measuring in all direc-
tions from there, but monitor the permeable
areas with the antenna (LogPer) directed and
6
positioned close to the wall . That is because
the antenna lobe widens with increasing fre-
quency. In addition reflections and cancella-
tions inside rooms make it difficult and often
impossible to locate the "leaks" accurately.
See the illustrating sketch below!
wall
right!
wrong!
potentially HF-permeable
part of the wall
antenna antenna
The uncertainty of localization with HF-antennas
The shielding itself should be defined and
surveyed by a specialist and in any case the
area covered by it should be much larger
than the leak
6
Please note: In this position the readings on the LCD
only indicate relative highs and lows that cannot be
interpreted in absolute terms.
Revision 4.5 (December 2006)
Limiting
tions and precautions
Precautionary recommentation for sleeping
areas for pulsed radiation
(Landessanitätsdirektion Salzburg, Austria)
The official regulations in many countries
specify limits far beyond the recommenda-
tions of environmentally oriented doctors,
"building biologists" and many scientific in-
stitutions and also those of other countries.
They are vehemently criticised, but they are
nonetheless "official". The limits depend on
frequencies and in the HF range of interest
here they are between 4 and 10 W/m², far
wall
beyond 10 million times the recommenda-
tions. Official limits are determined by the
potentiell
potential heat generation in the human body
durchlässiger
Bereich
and consequently measurements of averages
rather than peaks. This ignores the state of
environmental medicine. The "official" limits
are far beyond the range of this instrument,
which is optimized for accurate measurement
of power densities targeted by the building
biologists.
The standard SBM 2003 cited above classi-
fies power densities of below 1µW/m² as "no
anomaly" for non pulsed radiation in sleeping
areas, and for pulsed radiation one tenth of
that.
The "Bund für Umwelt und Naturschutz
Deutschland e. V." (BUND) proposes 100
values, recommenda-
Below 0.1 µW/m²
(SBM 2003)
below 1 µW/m²
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