Clampco Sistemi AT3000, Руководство пользователя

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User manual
Antenna model: AT3000
Rev 6.0 – September 2014
Clampco Sistemi is a registered trademark of Calzavara SpA – via Corecian, 60 – 33031 – Basiliano (Italy) http://www.clampco-sistemi.com/
In general, a passive receiving antenna picks up energy from the electromagnetic field being measured and makes
it available at the RF cable connector (5Ω). This means that the signal actually measured at the spectrum analyzer
depends not only on the amplitude of the electric field being measured, but also on the associated magnetic field
and its relative phase. Consequently, at a given frequency, the response of a passive antenna in two conditions of
equal electric field but with a different associated magnetic field (i.e. with different wave impedance) is not
necessarily identical. With regard to the usable band of the antenna in question, the problem arises in practice in
the vicinity of dipole array of FM radio systems (where the near field zone is more extensive). In this case, the error
will nevertheless be negligible because at these frequencies, internal antennas of AT3000 have high impedance.
More generally, however, it is advisable to compare near field measurements performed using passive antennas
with other measurements obtained with instruments (active antennas or wide band sensors) featuring a higher
receiving antenna impedance. In particular, in the near field zone of a RF source, it is advisable to measure the E
and H components of the field separately using respective instruments of known and adequate rejection of the
dual component.
3.9. AT 3000 Packaging
For transportations of the device (for example for return for calibration or service) always use its original case (or
wooden box wrapping AT3000 with a bag and fill the box with soft material). This will prevent from damage the
polystyrene radome and the antennas.
To avoid damaging
the antenna .
Do not apply any force between the sphere
and the handle.
Avoid taking the antenna from the sphere.
Do not crush the sphere.
Do not press the sphere against the border of
the carry case.
Figure 10 : Typical composition of the bag for AT3000