Gigahertz Solutions HF58B, Инструкция по эксплуатации

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© Gigahertz Solutions GmbH
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Made in Germany
To begin with use of the “Peak” setting to identify the main direction
of the source and to check if the pulses are above the surrounding
signal level.
Then switch to “Peak hold”. Several circles of the radar ray should
be awaited to reach a balance between drop and rise. This can take
several minutes. Depending on the type and distance of the radar
station, the real flux density will be at least a factor ten higher than
the displayed reading.
Please note that there are radar systems which operate at frequen-
cies between 8.5 and 9.5 GHz (naval, aviation, traffic and weather
radar), and which can be measured with our HFW59D.
Smart Meters
The frequencies / radio services implied are those of standard wire-
less communication standards. The challenge with measuring
emissions of smart meters lies in their duty cycles. They transmit
data in very short, but intensive bursts that happen only about every
1 to 10 or even more minutes, where the period between the bursts
is subject to change unpredictably.
To measure these bursts use the standard setting (Peak hold/VBW
standard), keep the meter in the same location and monitor it until
a burst occurs.
For the HF58B it is helpful to use the “-” (“minus”) setting for Peak
hold to catch the short bursts.
The HF58B-r and HF59B have a patented circuitry that allows for
the exact measurement of the extra fast rise times of the bursts
even in the “+”-setting for Peak hold.
Identify where the radiation enters a structure
As a first step eliminate sources from within the same room (e.g.
cordless phones, wireless routers, etc.). Once this is completed,
the remaining radiation will originate from outside. 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 radiation. To do this one should not stand in the
centre of the room, measuring in all directions from there, but mon-
itor the permeable areas with the antenna (LogPer) directed and
positioned close to the wall
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. That is because the antenna lobe wid-
ens with increasing frequency. In addition reflections and cancella-
tions inside rooms make it difficult and often impossible to locate
the “leaks” accurately. See the illustrating sketch below!
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Please note: In this position the readings on the LCD only indicate relative highs
and lows that cannot be interpreted in absolute terms.
wall
antenna
wall
antenna
potentiell
durchlässiger
Bereich
wrong!
right!
potentially HF-permeable
part of the wall
The uncertainty of localization with HF-antennas