Gigahertz Solutions HF58B, Инструкция по эксплуатации

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© Gigahertz Solutions GmbH
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Made in Germany
Important :
As the LogPer Antenna provided with this instrument is shielded
against ground influences one should “aim” about 10 degrees be-
low the emitting source one wants to measure. This is to avoid dis-
tortions of the reading.
The upper edge of the foremost resonator is a good “aiming aid”
for the required angle. It does not matter if the angle gets a little too
wide.
Our logarithmic periodic antenna, the “LogPer antenna”, provides
a distinct division of the horizontal and vertical polarization plane.
Also the frequency response is exceptional. There is a patent pend-
ing for its design.
(For professionals: For the technically rather difficult measurement
of the vertical polarization, it is significantly better shielded against the falsifying ground in-
fluences).
The missing directionality of standard telescope antennae is one of
the reasons why they are not suited for reliable HF measurements
in building biology EMR.
The readings from the instrument’s display always reflect the inte-
gral power density at the measurement location coming from the
direction the antenna is pointing at.
In order to avoid measurement values to be falsified by radiation
sources from frequencies below 800 MHz when measuring with the
LogPer antenna, the HF58B and the HF58B-r are equipped with an
internal high pass filter at 800 MHz.
As the HF59B picks up frequencies below 800 MHz, it has no inte-
grated high pass filter. However the filter is available for external
connection if needed, and is to be placed between the antenna en-
try and the antenna cable.
In addition, the HF59B is able to capture numerous sources of ra-
diation in the lower HF band which are not pulsed (i.e. amplitude
modulated). By their nature these non-pulsed sources are not avail-
able for audio analysis. That means you can get a significant read-
ing on the instrument without hearing any audio signal, which
makes the interpretation of the readings more difficult. To avoid this
source of misinterpretation the instrument marks those “inaudible”
signals by a
rattling tone , the loudness of which is in proportion to
its share in the total signal. The frequency of this marking is very
low (16 Hertz). An example of it can be found on our homepage.
With the switch to the right of the display in the “Pulse” position,
these sources of radiation as well as the corresponding rattling
“marking” are blanked out.
For a quantitative measurement of frequencies below 800 MHz with
the
HF59B , Gigahertz Solutions provides the active, horizontally
isotropic ultra broadband antenna UBB27_G3 responding to fre-
quencies from 27 MHz right up to more than 3.3 GHz.