Product Description - HP 84125C User Manual

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Product Description

The HP 84125C microwave EMI measurement test system is designed
to measure the radiated energy from an unintentional or intentional
radiator such as a transmitter or transceiver. It provides a system
level solution to make measurements above 1 GHz. The HP 84125C
system is designed to test products for EMI compliance to current FCC
regulations governing emissions and measuring to current ETSI and
CISPR regulations in the same frequency band.
The system is integrated into a portable instrument cart for easy
transport to and from the test location. There are two major
components of the system: a hand-held, tripod-mountable or antenna
mast-mountable test set and the spectrum analyzer mounted on an
instrument cart. The test set contains two low noise ampli ers,
high-pass lters, antenna, and interconnecting cables. A three-meter
RF cable assembly connects the test set to the spectrum analyzer
and allows the test set to be moved around without moving the
instrument cart. The RF cable assembly contains a rugged, low loss,
high frequency cable and two DC power cables for the ampli ers.
Each system is calibrated by Hewlett-Packard before shipment. The
calibration data consists of ampli er gain, cable loss, lter response,
and antenna factors. The data is then stored into data correction
tables which are loaded into the spectrum analyzer memory for easy
recall during each measurement band.
The calibration data is also stored on a 3.5 inch oppy disk during
factory calibration of the HP 84125C system and is shipped with each
HP 84125C system. The oppy disk contains the amplitude correction
factors for the test set (that is, ampli er gain, cable loss, and lter
response) and the antenna. In addition, the disk also contains a
MS-Windows utility that allows you to restore calibration data and
modify antenna data if needed.
To combine the functionality of the HP 8564E spectrum analyzer and
the test set, a downloadable program (DLP) has been provided. The
DLP provides the system softkeys that set the parameters for making
an EMI measurement. Hardware con gurations can be selected
enabling you to test the harmonic frequencies of your equipment
under test (EUT) while ltering out the fundamental frequencies.
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The DLP uses correction data to account for gain losses due to the
antenna, cables, ampli ers, and lters.
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