System checkout – ETS-Lindgren 4630 Refrad Reference Radiator (Archived) User Manual

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APPLICATIONS

MODEL 4630 REFRAD REFERENCE RADIATOR

REV F – PN 399214

REFRAD connected to it has to be set up at 10 different positions
on the turntable. These positions are specified in the reference
documents. The receive antenna is kept co-polarized at a constant
horizontal distance and is always facing the transmit antenna.
Transmission loss between the transmit and receive antennas is
measured according to the standard test procedure (height scan of
the receiving antenna) for each frequency and polarization.
During operation with CalStan, the REFRAD, test receiver or
spectrum analyzer, and antenna positioning mast are remotely
controlled. The operator is guided through the procedure by
commands appearing on the screen.

Data processing can de done after the antenna factors of the
transmit and receive antennas have been entered. Then, the
measured NSA is computed and plotted against the values given in
the standards. The +/- 4 dB- range is also shown for easy judgment
of the measurement results.

SYSTEM CHECKOUT

The system checkout is an efficient method for regular routine
checks of the whole system for radiated-emissions tests on the test
site. The REFRAD is set up on the turntable as the equipment
under test.

The signal from the comb generator is automatically measured and
the data is compared to the values that were measured previously.
Any observed differences are listed on the screen, otherwise the
statement “OK” is given.

This procedure is an “overall” check, the receive antenna,
preamplifier, antenna cable and test receiver or spectrum analyzer
operates as they do during routine radiated-emission testing. If any
component is defective, differing field-strengths will result.

The system checkout requires not more than 10 minutes. It is a
useful tool for quality control and should be performed once a
week. The computer automatically keeps a logbook of all
performed system checkouts. This logbook is a valuable element of
quality assurance of the EMC test laboratory.

Archived 3/18/10