LAPLACE INSTRUMENTS LTD
RF300
USER GUIDE
Page 14
Operation
Details of the measurements and limits are given in EN55015, section 4.4. A copy of
this should be consulted if performing compliance tests.
The UUT should be mounted on a wooden frame or table in the centre of the antenna.
The position is not critical.
Connecting cables to the EUT should leave the volume enclosed by the loops in such a
way as to be kept away from the loops to avoid capacitive coupling. See Fig C6 in
CISPR16.
Each axis (loop) should be measured in turn. Each should meet the requirements of the
standard. The loops are individually selected by connecting the short patch lead to the
appropriate input socket as shown in fig 11.
Measurement with the SA1002 or SA3000 and EMCEngineer Windows software.
1. Select the
RF300
item under the input menu. The vertical scale will indicate units
of dBuA. (If this item is not available, you need a later version of the software.
Contact your supplier)
2 Under the
limits
menu, select the
EN55015
.........
2m loop antenna
limit line.
3. Connect the switch unit to the analyser input.
4. With the UUT switched off, check the background signal level. At frequencies
below 1MHz, the background can be very strong. If strong signals do exist, check that
the analyser is not in compression by changing the input attenuator setting on the
analyser and comparing scans. Apart from the base line, the traces should overlay. If
this happens then it is OK to use the analyser with that attenuator setting. If not,
increase the attenuation and try again.
5. If the background is strong, it is advisable to either find a ‘quieter’ location or screen
the room.
6. Switch the UUT on. Check the levels of signal over the background levels using the
techniques used for conventional radiated testing as described in the user guide.
The levels displayed are fully compensated for the RF300 characteristics and can be
compared directly with the limit lines.
7. ALWAYS check for compression (overload) when taking measurements. The
amplitude of the reading on the screen cannot be used directly as a guide for
compression because the readings have been adjusted for the RF300 characteristics.
If it is suspected that the signals are too strong even with the attenuator switched in,
install the 10dB attenuator in the input lead to the switch unit. This additional
