Introduction; Safety Notice - Hameg HZ540 Benutzerhandbuch

Introduction

Probe power is supplied directly from HAMEG
Spectrum Analyzers. In case of different instru-
ments are used, probe power is supplied from
an optional 6 V power supply.
DC
The connection of the probe to the spectrum
analyzer, oscilloscope or measurement receiver
is made via a supplied SMA- to N-connector cable
of approximately 1.2 meters length. This length
is generally sufficient for most measurements.
If for special reasons a longer cable is used, the
insertion loss of this cable must be added to the
output values at the higher frequencies.
For normal measurements, the probes are
connected to a spectrum analyzer. These instru-
ments generally have an input impedance of 50
Ohms. This impedance is the normal termination
impedance for the probes. If an oscilloscope or
measurement receiver with a different input
impedance is used, an additional 50 Ohms feed-
through termination must be used. If the probe
is not loaded with a 50 Ohm impedance, it is not
calibrated.
The different probes are used for different tests
since their electric characteristics are quite
different. The E-field probe is normally used
at a distance of 0.5 to 1.5 meters from the RFI
source. The thereby observed frequencies are
then further localized near the source by use
of the H-field probe. The high impedance (Hi-Z)
probe makes further localization possible by
directly contacting the source and to judge the
effectiveness of suppression measures.
Because of its electrical characteristics, the E-
field probe is not intended to perform measure-
ments within an equipment or directly on parts
that are live. Electrical contact of the antenna
with live parts exceeding 20 V
may cause damage to the built-in pre-amplifier.
These limits also apply to the Hi-Z probe; howe-
ver, electrical contact to parts that are below 20
V or + 10 dBm are permitted.
DC
or + 10 dBm at RF
DC

Safety notice

Basically, it is not permissible to
perform measurements on parts
that are live above 30 V. Since a
significant part of the measurements
are performed on exposed parts,
it is a prerequisite that the user is
familiar with any potential electrical
hazard. Under no circumstances may
the probes be used on equipment
that is not safety grounded. When in
doubt, a safety isolation transformer
must be used.
The probes may not be used to perform accurate
quantitative measurements. It is not possible
to relate the probe measurements directly to
final values of field strength in V/m necessary
for certification tests. The probe kit is intended
as an aid for developmental tests to obtain a
qualitative amplitude as a function of frequency.
These values are strongly influenced by the limi-
ting conditions of the measurement which may
change as a function of frequency.
Subject to change without notice
I n t r o d u c t i o n
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