The High-Impedance Probe; The E-Field Monopole Probe - Hameg Instruments HZ530 Manual Del Usuario

The High-Impedance Probe

The E-Field Monopole Probe

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development components which are not suitable for EMC purposes.
The effectiveness of countermeasures can be judged easily. One
can investigate shields for "leaking" areas and cables or wires for
conducted interference.
The high-impedance probe (Hi-Z) permits the determination of the
radio frequency interference (RFI) on individual contacts or printed
circuit traces. It is a direct-contact probe. The probe is of very high
impedance (near the insulation resistance of the printed circuit
material) and is loading the test point with only 2pF (80 Ω at 1GHz).
Thereby one can measure directly in a circuit without significantly
influencing the relationships in the circuit with the probe.
One can, for example, measure the quantitative effectiveness
of filters or other blocking measures. Individual pins of IC's can
be identified as RFI sources. On printed circuit boards, individual
problem tracks can be identified. With this Hi-Z probe individual
test points of a circuit can be connected to the 50 Ω impedance of
a spectrum analyzer.
The E-field monopole probe has the highest sensitivity of the three
probes. It is sensitive enough to be used as an antenna for radio
or TV reception. With this probe the entire radiation from a circuit
or an equipment can be measured.
It is used, for example, to determine the effectiveness of shielding
measures. With this probe, the entire effectiveness of filters can be
measured by measuring the RFI which is conducted along cables
that leave the equipment and may influence the total radiation.
In addition, the E-field probe may be used to perform relative
measurements for certification tests. This makes it possible to
apply remedial suppression measures so that any requalification
results will be positive. In addition, pre-testing for certification tests
may be performed so that no surprises are encountered during the
certification tests.
Änderungen vorbehalten / Subject to change without notice