LAPLACE INSTRUMENTS RF6000 User manual

RF6000
RF SIGNAL SYNTHESISER
and SYSTEM CONTROLLER
USER GUIDE
ISSUE 1 May 2019
LAPLACE INSTRUMENTS LTD

Laplace Instruments Ltd Synthesiser Manual
Page 2
This page is intentionally blank

Laplace Instruments Ltd Synthesiser Manual
Page 3
INDEX
1. Specification
2. Special note
3. Introduction
4. Hardware description
4.1. Hardware interconnections
5. Software operation
5.1. Installation
5.2. Overview
5.3. Preparation
5.4. Standard Scan Mode
5.5. Single Point Mode
5.6. Custom scan mode
6. Software Reference
6.1. File
6.2. Display
6.3. Configure
7. Report Results screen controls

Laplace Instruments Ltd Synthesiser Manual
Page 4
This page is intentionally blank

Laplace Instruments Ltd Synthesiser Manual
Page 5
1.0 SPECIFICATION
Output carrier frequency: 80MHz – 6GHz
Resolution: 0.2% of current value
Step size: 0.2% to 9% of current
value
Level (carrier signal): -60dBm to 0dBm
Indication: Bargraph indication of
level.
THD (worst case): 10%
Modulation: off,
1KHz sine, 80% AM
modulation
200Hz, 20Hz & 1Hz
pulsed. 100% level
Output connector: N type
Ext. feedback probe: Input: 0-2.5V
Calibration via PC
software.
Connector: 8 pin circular
Indication: Bargraph
Mode: Open loop (pre-scan)
or closed loop.
EUT status: Qty 4, 0- 10v input
Fault modes: Stop, pause, continue.
Connector: BNC
EUT prompt: 4 pole c/o volt free
contacts.
Modes: Pulsed, Continuous, off
Connector: 15 pin Dee type
P.A. interlock: Contact closure
enforces standby
mode.
Connector: 4 pin circular
General
Supply: 110V or 230V, auto
sensing.
50 or 60Hz
Size: 120 x 64 x 188mm
Weight: 3.5kg
Control: From supplied PC software via
USB port.
Environment: Windows XP, Win7, Win8, Win10
Main control: Start test (RUN)
Stop test (STOP)
Pause at frequency (Dwell)
Single frequency mode
Setup screen: Enables all parameters of a test
scan and EUT details to be
programmed.
Parameters: Start and end frequencies
Frequency step (% of current
value)
Field strength (3 - 20V/m)
Dwell time (1 - 99 seconds)
Modulation mode.
Single freq. Screen: Manually or automatically ramp
the field strength at one
frequency.
Custom scan: Specify field level vs frequency
Report screen: Plot all details of the test including
setup parameters, actual vs. target
settings and EUT status.
Status window: Real time indication of operating
mode, EUT status and P.A. status.
Menus
File: All standard Windows facilities, including
printer output and file Save, Open
commands. Test results and setup data can
be stored/recalled separately.
Display: Set trace colours.
Add Title.
Config: Enter EUT monitor channel details
Select feedback probe type
Enter cell characteristics,
Check USB connections
Enter file path data.
Indication: Mains power
Output signal level (bargraph)
P.A. status, EUT status, EUT prompt

Laplace Instruments Ltd Synthesiser Manual
Page 6
This page is intentionally blank

Laplace Instruments Ltd Synthesiser Manual
Page 7
2. SPECIAL NOTE
The RF6000 is designed for use with the LaplaCell range of EMC test cells. These cells are
fitted with a field sensor to provide feedback to the field strength level control system. These
synthesisers will not work correctly unless this feedback signal is present.
If the unit is to be used without the cell connected, option –RH is available which should be
included at time of order. This adds a remote sensor interface which is connected via the RS232
port on the rear panel. This will accept feedback from Holaday, Narda, Radisense or other
standard probes that use similar protocols. In this mode the field level at the location of the probe
is controlled automatically.
2.1 Remote sensor option for anechoic chamber operation
The RF6000 can be used with a field sensors (see above) for use in anechoic chambers. This -RH
option must be specified at time of ordering. This manual will apply in all respects apart from the
following:
Sensor requirements:
The system is designed for the following sensor types….
Holaday HI-4422 or the HI-6005
Radisense RSS1004A probe and CTR1001S interface
Narda EP-600 range (or equivalents).
The sensor should be connected to the synthesiser via the appropriate fibre optic cable and serial
adaptor. This adaptor or serial cable is connected via the serial port provided on the rear panel of
the unit. The synthesiser will recognise the probe and power the adaptor automatically.
Note that the calibration data for the sensor must be correctly loaded and linked to the software
prior to use. This is normally undertaken by Laplace Instruments Ltd prior to despatch.
If the sensor is not connected, or if the sensor battery is flat, the system will not run when RUN
or PRE-SCAN is initiated.
In operation, the software will work as described in the following sections. Both closed loop
(sensor used alongside the EUT) and open loop (Pre-scanned with EUT absent) modes can be
used. In addition, the sensor can be used to check and calibrate the test volume using the pre-scan
mode and by processing the resultant pre-scan data in (for example) Excel.

Laplace Instruments Ltd Synthesiser Manual
Page 8
This page is intentionally blank

Laplace Instruments Ltd Synthesiser Manual
Page 9
3. INTRODUCTION
The RF6000 RF signal synthesiser is specifically designed to provide the signals required for
testing RFI immunity of products to international standard IEC61000-4-3.
IEC61000-4-3
IEC61000-4-3 immunity testing requires that the EUT (equipment under test) operates
satisfactorily when subject to a strong electromagnetic field.
This requires a scan at a certain fixed level (specified by the standard) of field strength. The
scan will comprise a series of ‘steps’ in frequency. Each step increase is specified as a
percentage of current frequency value.
This percentage is variable from 0.2% to 9%.
At each step, the frequency is held, the level adjusted to achieve the required field strength as
measured by a field sensor, a prescribed modulation mode is initiated and then the conditions
held for a ‘dwell’ time. The EUT should be monitored to detect faulty operation during the test.
During the dwell time, a 1KHz, AM modulation at 80% depth is applied to the signal.
In addition, a specific test is required in mobile phone bands with a pulsed modulation of 100%
depth to simulate the fields which may be experienced from mobile phones.
The synthesiser generates a signal at the required frequency, modulation and level which can be
fed to transmitting antenna or test chamber via a suitable fixed gain Power Amplifier. If used
with a compact cell, the Laplace RF1100, RF1300 and/or RF1600 amplifiers make ideally
matched companions.
Typical System
Frequency and modulation are simple set values but the level is controlled via a field strength
sensor feedback loop. (But see note in section 2).
The PC will provide the level set point in terms of sensor output (i.e. already adjusted to take
account of cell characteristics)
Two operating modes are available: real time feedback or pre-scanned level. The former takes
account of the effect of the EUT inside the cell.

Laplace Instruments Ltd Synthesiser Manual
Page 10
The Synthesiser also acts as an interface to the EUT with status input and ‘prompt’ outputs that
can initiate the product to perform an operating cycle at each step.
A single frequency mode is available in which the cell is effectively controlled directly by the
operator from the PC, enabling specific weaknesses in the EUT to be investigated.
System components
 Synthesiser The RF6000. Linked to PC via USB port. Generates the required signals and
controls the amplitude to produce required field strength inside cell. Also interfaces simple
EUT status signal back to PC and generates simple ‘prompt’ signal to EUT under PC control
 PC with RFSynth6 software package. This acts as the User interface and main controller for
the system.
 EUT monitoring facilities
 EUT excitation and monitoring. The RF6000 is fitted with 4 channels of 0 – 10v
inputs to monitor the EUT status.
 Video interface running in separate window. Camera and camera hardware interface
and software are supplied separately.
The interface between the EUT and the RF6000 must be produced by the user to suit the
requirements of the EUT.
Cell characteristics
The cell may be distinctly non linear in frequency characteristics. Generally each cell is
individually calibrated by the manufacturer and the resultant characteristics programmed into the
software.
Field control technique
There are two quite distinct ways in which field strength can be controlled. The synthesiser
allows use of both techniques.
To understand the background to these alternative techniques, imagine the following scenario:
The equipment to be tested (EUT) is to be used in an area close to a strong transmitter, perhaps a
TV station, and may therefore be subject to quite strong RF fields. Indeed in one location at
which the product is to be located, the field strength from the transmitter is 10V/m, as measured
with an accurate field strength probe prior to installing the product. When the product is installed
at this location, it will modify the field in this vicinity, possibly reducing the field to only 5V/m
simply due to the RF characteristics of the product.
The question is therefore raised: how should the product be tested?
Either:
1. Open loop mode (Pre-scan). Generate the 10V/m in the ‘empty’ space first, then place the
product into that space but do not attempt to control the field strength which may now
have suffered a significant change. This emulates the ‘real world’ situation as described
above, but may result in actual field strengths applied to the product significantly less
than the 10V/m nominal.
Or:
2. Closed loop mode (Standard). Control the field strength with the product in the ‘space’ to
give 10V/m. This may appear to to more ‘correct’ but could give a false impression of
the performance of the produce in actual situations.
The synthesiser and the software permit both techniques.
Technique 1 is the preferred method (according to the standard), but technique 2 is often used.