Gigahertz Solutions HF58B, Инструкция по эксплуатации

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© Gigahertz Solutions GmbH
Made in Germany
Quantitative Measurement:
Determination of Total High Frequency Pollution
As described in Getting Started, attach the LogPer antenna to the
HF analyser. Hold the HF analyser with a slightly outstretched
arm because objects (mass) directly behind it “like yourself”, have
effects on the testing result. Your hand should not get too close to
the antenna, but should be near the bottom end of the instrument.
In the area of a local maximum, the positioning of the HF analyser
should be changed until the highest power density (the most im-
portant measurement value) can be located. This can be achieved
as follows:
-
When scanning “all directions” with the LogPer to locate the
direction from which the major HF emission(s) originate, move
your wrist right and left. For emission sources behind your back,
you have to turn around and place your body behind the HF an-
alyser. When scanning with the isotropic UBB27 aerial (HF59B),
it is sufficient to move the instrument to see the field distortions
effected by your body.
-
Through rotating the HF analyser , with attached LogPer an-
tenna, around its longitudinal axis, determine the polarization
plane of the HF radiation. When using the UBB27 (HF59B) you
only need to do this in locations where radiation from directly
below or above cannot be ruled out (multistorey buildings, town
houses, etc)
-
Change the measurement position and avoid measuring ex-
clusively in one spot, because that spot may have local or an-
tenna-specific cancellation effects.
Some manufacturers of field meters propagate the idea that the ef-
fective power density should be obtained by taking measurements
of all three axes and calculating the result. Most manufacturers of
professional testing equipment, however, do not share this view.
In general, it is well accepted that
exposure limit comparisons should be based on the maximum
value emitted from the direction of the strongest
radiation source. When using the UBB27, of course, the direc-
tional component will not apply.
But the details of the situation need to be considered! For example,
if a 2.4-GHz telephone inside the house emits a similar level of mi-
crowaves as a nearby cellular phone base station outside the
house, it would be helpful to first turn off the 2.4-GHz telephone in
the house. Now measure the exposure level originating from the
outside. After having measured the emission of the 2.4-GHz tele-
phone on its own, the sum of both measurement values could be
used for the exposure assessment. (This is necessary only when
using the LogPer aerial. The isotropic UBB27 does this in a single
measurement).