User manual

Digital High Frequency Analyser HF58B-r
© Gigahertz Solutions GmbH, 90579 Langenzenn, Germany Revision 4.5 (Febuary 2006) Page 11
µW/m² outside buildings. In view of the
shielding properties of normal building mate-
rials, far lower values exist inside buildings.
In February 2002 the Medical Authority of the
Federal State Salzburg, Austria, recommends
to reduce its “Salzburger Precautionary Rec-
ommendation” from 1 000 µW/m² to 1 µW/m²
inside buildings and 10 µW/m² outside.
These limits are based on empirical evidence
over the past few years.
The ECOLOG-Institute in Hannover, Ger-
many made a recommendation only for out-
side areas, namely 10000 µW/m². This is well
above the recommendation by building bi-
ologists and aims at getting consent also
from the industry. This would possibly enable
a compromise for a more realistic limit than
the government regulations cited above. The
authors qualify their recommendation in
- The limit should be applicable to the maxi-
mum possible emission of the transmitting
stations. As the emission measured de-
pends on the constantly varying actual
load, this restricts the normal exposure
much further.
- A single station should not contribute more
than one third to this total.
- The extensive experience and findings of
medical and building biology specialists
could not be considered for the proposed
limits, as their results are not sufficiently
documented. The authors state, that “sci-
entific scrutiny of their recommendations is
needed urgently”.
- Not all effects on and in cells found in their
research could be considered for the pro-
posed limits, as their damaging potential
could not be established with sufficient cer-
tainty.
In summary it confirms the justification of
precautionary limits well below the pre-
sent legal limits.
Note for owners of cellular phones:
Unimpaired reception of calls is possible with
power densities far below even the very strict
precautionary recommendation of 0.1 µW/m²
for pulsed HF frequencies by the SBM 2003.
Audio Frequency Analysis
Many different frequencies within the fre-
quency band between 800MHz and 2.5GHz,
are being used by many different services.
The audio analysis of the modulated portion
of the HF signal, help to identify the source
of a given HF radiation signal.
First get the HF analyzer ready for testing by
following the instructions in the relevant sec-
tion.
Important: For the audio analysis switch the
small switch on the right of the display to
“Pulse”. This will eliminate the content of
unpulsed signals, since their acoustical
marking (“rattling” with 16 Hz) will make the
acoustical analysis difficult.
How to proceed:
For audio analysis, simply turn the volume
knob of the speaker at the top of the case all
the way to the left (“-“). If you are switching
to audio analysis while high field strength
levels prevail, high volumes can be generated
quite suddenly. This is especially true for
measurements which are to be taken without
audio analysis. The knob is not fastened with
glue to prevent over winding. However, if by
accident you should turn the knob too far,
simply turn it back again. No damage will be
caused.
Set the On/OFF switch at
.
Sounds and signals are very difficult to de-
scribe in writing. The best way to learn the
signals is to approach known HF sources
very closely and listen to their specific signal
patterns. Without detailed knowledge, the
characteristic signal patterns of the follow-