Pickering 20-745 User manual

Page (1)
R.F. MULTIPLEXER MODULE 20-745
pickering
Issue 5.1 July 2019
User Manual
GPIB RF Multiplexer Module
(Model No. 20-745)
pickeringtest.com pickering
SYSTEM 10/20
*Please contact Pickering for alternative
PXI/LXI/USB solutions
*

Page (II) R.F. MULTIPLEXER MODULE 20-745
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Page (II) REED RELAY MODULE 40-110/115/120/125
pickering
© COPYRIGHT (2019) PICKERING INTERFACES. ALL RIGHTS RESERVED.
No part of this publication may be reproduced, transmitted, transcribed, translated or stored in any form, or by
any means without the written permission of Pickering Interfaces.
Technical details contained within this publication are subject to change without notice.
ISO 9001
Reg No. FM38792

Page (III)
R.F. MULTIPLEXER MODULE 20-745
pickering
Page (III)
REED RELAY MODULE 40-110/115/120/125
pickering
TECHNICAL SUPPORT
For Technical Support please contact Pickering Interfaces either by phone, the website or via e-mail.
WARRANTY
All products manufactured by Pickering Interfaces are warranted against defective materials and workmanship for a period of
three years, excluding programmable power supplies, from the date of delivery to the original purchaser. Any product found to be
defective within this period will, at the discretion of Pickering Interfaces be repaired or replaced.
Products serviced and repaired outside of the warranty period are warranted for ninety days.
Extended warranty and service are available. Please contact Pickering Interfaces by phone, the website or via e-mail.
ENVIRONMENTAL POLICY
Pickering Interfaces operates under an environmental management system similar to ISO 14001.
Pickering Interfaces strives to full all relevant environmental laws and regulations and reduce wastes and releases to the
environment. Pickering Interfaces aims to design and operate products in a way that protects the environment and the health and
safety of its employees, customers and the public. Pickering Interfaces endeavours to develop and manufacture products that can
be produced, distributed, used and recycled, or disposed of, in a safe and environmentally friendly manner.
Worldwide Technical Support and Product Information
pickeringtest.com
Germany
Tel: [phone]
E-mail: [email protected]
Sweden
Tel: [phone]
E-mail: [email protected]
USA
Tel: (West) [phone]
Tel: (East) [phone]
E-mail: [email protected]
Czech Republic
Tel: [phone]
E-mail: [email protected]
France
Tel [phone]
E-mail [email protected]
Pickering Interfaces Headquarters
Stephenson Road Clacton-on-Sea CO15 4NL United Kingdom
Tel: [phone]
E-Mail: [email protected]
China
Tel: [phone]
E-mail: [email protected]

Page (IV) R.F. MULTIPLEXER MODULE 20-745
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Page (IV) GENERAL PURPOSE REED RELAY MODULE 10-110/115/120/125
pickering
Page (IV) REED RELAY MODULE 40-110/115/120/125
pickering
MEANING / DESCRIPTION SYMBOL
PROTECTIVE EARTH (GROUND)
To identify any terminal which is intended for connection to an external conductor for
protection against electric shock in case of a fault, or the terminal of a protective earth
(ground) electrode.
DANGEROUS VOLTAGE
To indicate hazards arising from dangerous voltages.
WARNING / CAUTION
An appropriate safety instruction should be followed or caution to a potential hazard
exists.
Refer to the relevant instructions detailed within the product manual.
HEAVY
If this product is heavy reference should be made to the safety instructions for
provisions of lifting and moving.
STATIC SENSITIVE
To indicate that static sensitive devices are present and handling precautions should
be followed.
!
kg
SAFETY SYMBOLS
PRODUCT SAFETY
The following safety symbols may be used on the product and throughout the product documentation.

Page (V)
R.F. MULTIPLEXER MODULE 20-745
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Copyright Statement ...................................................................II
Technical Support and Warranty................................................III
Product Safety .............................................................................IV
Contents (this page)....................................................................V
Warnings and Cautions ..............................................................VII
Section 1
Technical Specication...............................................................1.1
Section 2
Technical Description .................................................................2.1
Functional Description..........................................................2.1
Section 3
Installation....................................................................................3.1
Pre-Operation Checks...........................................................3.1
Hardware Installation ............................................................3.1
Software Installation .............................................................3.3
Self-Test..................................................................................3.3
Section 4
Programming Guide....................................................................4.1
Programming the Module .....................................................4.1
Section 5
Connector Information................................................................5.1
Section 6
Trouble Shooting.........................................................................6.1
Installation Problems ...........................................................6.1
Section 7
Maintenance Information............................................................7.1
Relay Lookup Tables.............................................................7.1
PCB and Component Layout................................................7.3
CONTENTS
Please use the hyperlinked text to navigate to the page required

Page (VI) R.F. MULTIPLEXER MODULE 20-745
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Page (VII)
R.F. MULTIPLEXER MODULE 20-745
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Page (VII)
GENERAL PURPOSE REED RELAY MODULE 10-110/115/120/125
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WARNINGS AND CAUTIONS
WARNING - HAZARDOUS ENVIRONMENTS SYMBOL
This product is not specically designed for use in hazardous environments, for example in explosive
atmospheres. If the product is to be used in hazardous environments we recommend that the user
ensures suitable protective measures are taken.
!
WARNING - DANGER OF ELECTRIC SHOCK SYMBOL
This module may contain hazardous voltages. Before removing the module from the rack remove all
supplies and disconnect user I/O signals.
Unused slots in the System 10/20 chassis are populated with blanking plates to prevent access
to user I/O signals that may be present. Blanking panels are available to order from Pickering in a
variety of slot widths. If the product is not used in this manner for example by using an extender card
then additional care must be taken to avoid contact with exposed signals.
CAUTION - HANDLING OF ELECTROSTATIC-SENSITIVE DEVICES SYMBOL
Certain semiconductor devices used in this equipment are liable to damage due to static voltage.
Observe the following precautions when handling these devices in their unterminated state, or
sub-assemblies containing these devices:
1. Persons removing sub-assemblies from equipment using these devices must be earthed by a
wrist strap and a resistor at the point provided on the equipment.
2. Soldering irons used during the repair operations must be low voltage types with earthed tips and
isolated from the mains voltage by a double insulated transformer.
3. Outer clothing worn must be unable to generate static charges.
4. Printed Circuit Boards (PCBs) tted with these devices must be stored and transported in
anti-static bags.
CAUTION - PRODUCT DOCUMENTATION SYMBOL
Suitably qualied & trained users should ensure that the accompanying documentation is fully read
and understood before attempting to install or operate the product.
!
SAFETY INSTRUCTIONS
SAFETY INSTRUCTIONS
All cleaning and servicing requires the equipment to be isolated and disconnected from the power source and user I/O
signals (refer to the Maintenance Section).
• Appropriate manual handling procedures should be followed as dictated by the weight of the individual module or
the combined weight of the modules & chassis.
• Should a fault occur with the module or chassis, immediately isolate and disconnect the incoming power to the
chassis and the user I/O signals.
• Ensure the equipment is installed, operated and maintained by trained and authorised personnel.

Page (VIII) R.F. MULTIPLEXER MODULE 20-745
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THIS PAGE INTENTIONALLY BLANK

Page 1.1
R.F. MULTIPLEXER MODULE 20-745
pickering SECTION 1 - TECHNICAL SPECIFICATION
SECTION 1 - TECHNICAL SPECIFICATION
pickeringtest.com
GPIB 2GHz RF Multiplexer Module 20-745
ISSUE 4.5 JUL 2019
• R.F. Multiplexer with up to 2GHz Bandwidth
• Configurable as 32 to 1, Dual 16 to 1 or Quad 8 to 1
Multiplexer
• Wide Choice of Connectors: SMB, BNC, BT Type
43/SMZ, SMA or 1.0/2.3
• Built-In Self Test
• Front Panel LED Indicators
• Suitable for Building Larger Switching Networks
• 75Ω Version Suitable for Telecoms and High
Quality Video Switching
Programming
The Multiplexer module is simple to program:-
ARESET a Open all channels on device a
DELAY t Force a minimum delay of tmilliseconds
between two instructions
DIAGNOSTIC? Report any Self Test errors
RESET Open all switches on all modules
VIEW? aView status of device a
CHAN a,b,c
Select channel con multiplexer a, bank b
Self Test
Self-Test is invoked at power on and may also be operated under
software (*TST?) or via a recessed push button. Self-Test pass
is indicated on a front panel LED with a full pass/fail description
available using the DIAGNOSTIC? command. Self-Test
comprises 2 levels:
• Logic Test
• Relay Coil Test
These two levels of testing will nd the majority of failures, however
please note that the relay contacts themselves are not tested.
1
2
3
4
5
16
Common
MUX Bank 1
1
2
3
4
5
16
Common
MUX Bank 2
1
2
3
4
5
32
Common
1
2
3
4
5
8
Common
MUX Bank 1
1
2
3
4
5
8
Common
MUX Bank 2
1
2
3
4
5
8
Common
MUX Bank 3
1
2
3
4
5
8
Common
MUX Bank 4
1
2
3
4
5
16
Common
MUX Bank 1
1
2
3
4
5
16
Common
MUX Bank 2
1
2
3
4
5
32
Common
1
2
3
4
5
8
Common
MUX Bank 1
1
2
3
4
5
8
Common
MUX Bank 2
1
2
3
4
5
8
Common
MUX Bank 3
1
2
3
4
5
8
Common
MUX Bank 4
Single 32
Channel Mode
Dual 16
Channel Mode
Quad 8 Channel Mode
1
2
3
4
5
16
Common
MUX Bank 1
1
2
3
4
5
16
Common
MUX Bank 2
1
2
3
4
5
32
Common
1
2
3
4
5
8
Common
MUX Bank 1
1
2
3
4
5
8
Common
MUX Bank 2
1
2
3
4
5
8
Common
MUX Bank 3
1
2
3
4
5
8
Common
MUX Bank 4
The 20-745 series are a range high density 2000MHz Multiplexers
arranged as a Quad 8 to 1, Dual 16 to 1 or Single 32 to 1
conguration, all with excellent Insertion Loss, VSWR & Isolation,
available in a choice of 50Ωor 75Ωversions with SMA, SMB, Type
43/SMZ, BNC or 1.0/2.3 Connectors.
This module may also be easily congured as a Single 32 to 1,
Dual 16 to 1 or Quad 8 to 1 multiplexer, to ease the construction of
large RF switching systems.
This module is a higher density version of type 20-740 with the
automatic termination function removed, the RF performance
specication.
Applications for the 20-745 include routing high frequency signals
to and from oscilloscopes, analyzers, signal generators and
synthesizers, telecoms tributary switching, video/audio switching
and switching high frequency logic signals.
*Please contact Pickering for alternative
PXI/LXI/USB solutions
*

Page 1.2 R.F. MULTIPLEXER MODULE 20-745
pickering
SECTION 1 - TECHNICAL SPECIFICATION
2GHz RF Multiplexer Module – 20-745
pickeringtest.com
Specifications
Specification (16 to 1 Mode)
Characteristic Impedance: 50Ω or 75Ω
Maximum Frequency:
Rise Time:
1500MHz
<0.5ns
Maximum Insertion Loss:
V.S.W.R. (at 1300MHz):
Isolation (at 2000MHz):
Crosstalk (at 2000MHz):
<2dB
<1:1.6
>75dB
>55dB
Maximum Hot Switch Voltage:
Maximum Power:
Termination Resistor Max Power:
Maximum Switch Current:
Nominal Switching Capacity:
30V DC
10W
0.25W
0.5A
0.01A, 24Vdc,
[email protected]
On Path Resistance:
Off Path Resistance:
Differential Thermal Offset:
<250mΩ
>108Ω
<20µV
Switching Time: 10ms
Expected Life, Mechanical:
Expected Life, Electrical (low power):
Expected Life, Electrical (max power):
>1x106operations
>3x105operations
>3x105operations
Additional Specification (8 to 1 Mode)
Maximum Frequency: 2000MHz
Additional Specification (32 to 1 Mode)
Maximum Frequency: 1000MHz
500MHz 1000MHz 1500MHz
20-745 VSWR (RETURN LOSS)
1.6
1.4
1.2
1.0
1.8
2000MHz
13dB
16dB
21dB
11dB
VSWR
Return Loss
26dB
0 dB
-0.8 dB
-1.2 dB
-1.6 dB
-2.0 dB
-2.4 dB
-2.8 dB
-0.4 dB
500MHz 1000MHz 1500MHz
20-745 INSERTION LOSS
-3.2 dB
2000MHz
Typical RF Performance Plots for 20-745 in Dual 16 to
1 Mode (SMB/Type 43 connector)
90%
50%
10%
200pS400pS600pS
20-745 TYPICAL
STEP RESPONSE
400pS
-80 dB
-90 dB
-70 dB
-100 dB
500MHz 1000MHz 1500MHz
20-745 ISOLATION
2000MHz
-40 dB
-50 dB
-60 dB
-30 dB
-50 dB
-60 dB
-70 dB
-80 dB
-90 dB
-40 dB
500MHz 1000MHz 1500MHz
20-745 CROSSTALK
2000MHz
Mechanical Characteristics
All modules conform to the 6U height (262mm) Eurocard standard
and are 160mm deep, panel width is 1.8 Inches (45.7mm).
Connectors
The 20-745 RF Multiplexer Module is available with BNC, SMA,
SMB, Type 43/SMZ or 1.0/2.3 connectors. Other connector types
are available to order, please contact the sales ofce for details.
1.8"
1.8"
POW
ACT
ERR
MAN
TEST
TEST
High Density
50-Way
MMC
Coaxial
Connector
SMB or
Type 43
Coaxial
Connector
(36 per
module)
POW
ACT
ERR
MAN
TEST
TEST
32 Channel
Indicator
LEDs

Page 1.3
R.F. MULTIPLEXER MODULE 20-745
pickering SECTION 1 - TECHNICAL SPECIFICATION
2GHz RF Multiplexer Module – 20-745
pickeringtest.com
Ordering Information
© Copyright (2019) Pickering Interfaces. All Rights Reserved Pickering Interfaces maintains a commitment to continuous product development, consequently we reserve the right to vary from the description given in this data sheet.
Product Customization
Pickering System 20 modules are designed and manufactured
on our own exible manufacturing lines, giving complete product
control and enabling simple customization to meet very specic
requirements.
Customization can include:
• Alternative relay types
• Mixture of relay types
• Alternative number of relays
• Different performance specications
All customized products are given a unique part number, fully
documented and may be ordered at any time in the future. Please
contact your local sales ofce to discuss.
Product Order Codes
RF Multiplexer, 50Ω:
2000MHz, SMB
2000MHz, SMA
1300MHz, BNC
20-745-501
20-745-521
20-745-531
RF Multiplexer, 75Ω:
1500MHz, Type 43/SMZ
1000MHz, BNC
1500MHz, 1.0/2.3
20-745-701
20-745-731
20-745-741
The default conguration should be specied when ordering
(Quad 1 to 8, Dual 16 to 1 or Single 32 to 1)
Operating/Storage Conditions
Operating Conditions
Operating Temperature:
Humidity:
Altitude:
0°C to +55°C
Up to 95% non-condensing
5000m
Storage and Transport Conditions
Storage Temperature:
Humidity:
Altitude:
-20°C to +75°C
Up to 95% non-condensing
15000m
Safety & CE Compliance
All modules are fully CE compliant and meet applicable EU
directives: Low-voltage safety EN61010-1:2010, EMC Immunity
EN61326-1:2013, Emissions EN55011:2009+A1:2010.
Mating Connectors & Cabling
50Ω SMB to SMB Lead, 1m Length
50Ω SMA to SMA Lead, 1m Length
50Ω BNC to BNC Lead, 1m Length
75Ω BNC to BNC Lead, 1m Length
75Ω 1.0/2.3 to 1.0/2.3 Lead, 1m Length
75Ω SMZ to SMZ Lead, 0.5m Length
10-987-510
10-981-510
10-980-510
10-980-710
40-977-731
10-988-705
50Ω MMC Co-ax Crimp Pins
75Ω MMC Co-ax Crimp Pins
10-986-005
10-986-007
For other connection accessories for this series of modules please
refer to the 90-011D RF Cable Assemblies data sheet where a
complete list and documentation can be found for accessories, or
refer to the Connection Solutions catalog.

Page 1.4 R.F. MULTIPLEXER MODULE 20-745
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SECTION 1 - TECHNICAL SPECIFICATION
Voltage Supplies
Logic Supply 5Vdc ±5%
Relay Supply 12Vdc ±10%
Electrical & Mechanical Specications
† Approx. dimensions. Standard 160mm Eurocard.
Model 20-745
Approx. Weight 0.8kg
Dimensions (mm) 6U Eurocard
as specied in
DIN41494
Front Panel Width 45.7
Height 268
Overall Length † 189
Power /Current Consumption
Max 5V 250mA
12V 100mA
Min. 5V 150mA
12V 0mA

Page 2.1
R.F. MULTIPLEXER MODULE 20-745
pickering SECTION 2 - TECHNICAL DESCRIPTION
SECTION 2 - TECHNICAL DESCRIPTION
FUNCTIONAL DESCRIPTION
Figure 2.1 - R.F Multiplexer Module: Functional Block Diagram
CHANNEL STATUS LEDs
DRIVER
PCB ASSY
FRONT PANEL CONNECTORS
RELAY
COILS
RELAY
CONTACTS
TO FRONT
PANEL
DRIVER
ICs
STATUS LEDs
TO FRONT
PANEL
CONNECTOR J1
MULTIPLEXER
PCB ASSY
A functional block diagram is provided in Figure 2.1. The module is powered via the chassis connector J1 with +12V
relay and +5V logic supplies. The interface to the user test equipment is via the front panel mounted connectors. The
module comprises a System 20 Driver Board and R.F Multiplexer PCB assembly populated with electro-mechanical
relays.
The module is available as a Single 32 to 1, Dual 16 to 1, or Quad 8 to 1 R.F multiplexer utilising SPDT changeover
relays with a choice of front panel connectors. The relay drivers on the Multiplexer PCB are fed with serial data from
the Driver PCB Assy. Relay switching is determined by operator programming. Status LEDs are provided on the
front panel.
Relay circuits for the different congurations are shown in Figures 2.2 to 2.4.

Page 2.2 R.F. MULTIPLEXER MODULE 20-745
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SECTION 2 - TECHNICAL DESCRIPTION
RL9
RL8
RL3
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
Relay interconnects:
PLAIN => fixed connection
DASHED => configurable connection
C1
RL1
RL6
RL11
RL16
RL14
RL20
RL27
RL22
RL25
RL28
RL30
RL35
RL33
RL29
RL32
RL21
RL24
RL15
RL7
RL19
RL18
RL2
RL4
RL10
RL12
RL26
RL34
RL17
RL5
RL13
RL23
RL31
Figure 2.2 - R.F Relay Circuit (Single 32 Channel Conguration)

Page 2.3
R.F. MULTIPLEXER MODULE 20-745
pickering SECTION 2 - TECHNICAL DESCRIPTION
C1
(Bank 1 common)
(Bank 2 common)
C3
RL9
RL8
RL3
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
Relay interconnects:
PLAIN => fixed connection
DASHED => configurable connection
RL1
RL6
RL11
RL16
RL14
RL20
RL27
RL22
RL25
RL28
RL30
RL35
RL33
RL29
RL32
RL21
RL24
RL15
RL7
RL19
RL18
RL2
RL4
RL10
RL12
RL26
RL34
RL17
RL5
RL13
RL23
RL31
RL19 Unused
Figure 2.3 - R.F Relay Circuit (Dual 16 Channel Conguration)

Page 2.4 R.F. MULTIPLEXER MODULE 20-745
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SECTION 2 - TECHNICAL DESCRIPTION
C1
(Bank 2 common)
(Bank 3 common)
(Bank 4 common)
(Bank 1 common)
C3
C4
C2
RL17,18,19 Unused
RL9
RL8
RL3
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
Relay interconnects:
PLAIN => fixed connection
DASHED => configurable connection
RL1
RL6
RL11
RL16
RL14
RL20
RL27
RL22
RL25
RL28
RL30
RL35
RL33
RL29
RL32
RL21
RL24
RL15
RL7
RL19
RL18
RL2
RL4
RL10
RL12
RL26
RL34
RL17
RL5
RL13
RL23
RL31
Figure 2.4 - R.F Relay Circuit (Quad 8 Channel Conguration)

Page 3.1
R.F. MULTIPLEXER MODULE 20-745
pickering SECTION 3 - INSTALLATION
Page 3.1
GENERAL PURPOSE REED RELAY MODULE 20-110/115/120/125
pickering SECTION 3 - INSTALLATION
SECTION 3 - INSTALLATION
Power Supply
with
Interface Module
above
6U System 20 Modules
(Not position dependent)
3U System 10 Modules
(Not position dependent)
kg
PRE-OPERATION CHECKS (UNPACKING)
1. Check the module for transport damage and report any damage immediately to Pickering Interfaces.
Do not attempt to install the product if any damage is evident.
2. Position the chassis relative to any other equipment the module(s) will connect with. Ensure the chassis is not
connected to the electrical supply.
3. Ensure that the designated area for the chassis containing the module is of at and solid construction to
withstand and support the combined weight of the module(s) and chassis.
!
Refer to the Warnings and Cautions at the front of this manual
Modular products require installation in a suitable System 10/20 chassis.
The module is designed for indoor use only.
!
HARDWARE INSTALLATION
ELECTRICAL CONNECTION (CHASSIS)
1. The chassis must be electrically installed in accordance with local regional electrical codes by a qualied
engineer.
2. Ensure the power supply lead provides the necessary integrity of chassis ground.
Electrostatic discharge can damage the components on the module. To avoid such damage in handling the
board refer to page VII.
Ensure that there is adequate ventilation.
Figure 3.1 - System 10/20 Front Access Case Split 24/60 with Various Modules Fitted.

Page 3.2 R.F. MULTIPLEXER MODULE 20-745
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SECTION 3 - INSTALLATION
Page 3.2 GENERAL PURPOSE REED RELAY MODULE 20-110/115/120/125
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SECTION 3 - INSTALLATION
Figure 3.2 - Module Guide Rail Position
Figure 3.3 - A Partially Built System 20 Front Access Chassis
!
MODULE INSTALLATION
The module should be installed in accordance with the following procedure:
1. Ensure that the system is turned OFF but still connected to mains so that it remains grounded.
2. If the module has address switches ensure they are set to the appropriate position. (See Section 4).
Note individual modules are not sent out with a system drawing detailing their address.
3. Choose an appropriate slot in the rack and remove the blanking plate (if tted).
(See the Pickering 10-910M IEEE-488 GPIB System 10/20 Ancillaries manual for further details).
(When tted, additional modules will be automatically recognised by the interface card. See Figure 3.1).
4. If necessary t the module guide rails as supplied with the module to both the top and bottom of the chassis
in that slot position. One guide rail slot should be to the left of the connector as shown in Figure 3.2.
5. Align the module with the backplane and screw holes at the front of the chassis.
Hold the handle whilst slowly sliding the module into the card guides until the module seats rmly into the
backplane. See Figure 3.4. The front panel of the module should be ush with the front or rear panel of the
chassis.
6. Screw the front panel of the module to the chassis front panel mounting rails.
7. Ensure all necessary modules including the power supply are tted to the rack and other slots blanked off
before powering up.
To achieve the correct initialisation of the sytem, ensure any slave chassis are powered up before the master
chassis.

Page 3.3
R.F. MULTIPLEXER MODULE 20-745
pickering SECTION 3 - INSTALLATION
Page 3.3
GENERAL PURPOSE REED RELAY MODULE 20-110/115/120/125
pickering SECTION 3 - INSTALLATION
Figure 3.4 - Module Insertion in a Pickering 20-935A-001 Front Access Chassis
SOFTWARE INSTALLATION
Refer to the Pickering manual 10-921M.
For the latest version of the driver please refer to our web site pickeringtest.com where links to our Software
Download page will provide the driver software for the various programming environments encountered.
SELF-TEST FUNCTION
Self-Test is invoked at power on and may also be operated under software (*TST?) or via a recessed push button. Self-Test pass
is indicated on a front panel LED with a full pass/fail description available using the DIAGNOSTIC? command.
Self-Test comprises 2 levels, see Figure 3.5:
1. Logic Test: Checks all logic including on-board microprocessor, relay drivers etc.
2. Relay Coil Test: All reed relay coils are checked for continuity.
Note: In the unlikely event of a relay needing replacement, a spare relay is mounted on the module circuit board to facilitate easy
maintenance with minimum downtime. Additional relays are available from Pickering Interfaces.
Self-Test Operation
If Self-test is run under software control it will rstly clear the whole module (Manual Test will only function when the module is
in a clear state).
When the self-test has nished the multiplexer will be returned to an all clear state (i.e. the previous state will not be remembered!).
Detailed Self-Test Reporting using the DIAGNOSTIC? Query
The DIAGNOSTIC? query will give an ASCII string detailing any self test failures. These will include:
Logic: Microprocessor, RAM, EPROM, Relay Drivers, Invalid Link Settings etc.
Relay Coils: Open Circuit Coil.
This string is not intended to be processed by the user’s software, it is suitable for copying directly onto the screen of your control
computer. This information will then indicate maintenance required (please contact Pickering for further help).

Page 3.4 R.F. MULTIPLEXER MODULE 20-745
pickering
SECTION 3 - INSTALLATION
SELF TEST INITIATED BY:
• POWER ON
• *
TST? QUERY
• MANUAL BUTTON
CLEAR MODULE
LOGIC TEST:
• MICROPROCESSOR BOARD
• RELAY BOARD
LOGIC TEST
FAIL ?
RELAY COIL
TEST FAIL ?
RELAY COIL TEST
SELF TEST PASS
SELF TEST FAIL:
• ERROR LED ON
• USE DIAGNOSTIC?
COMMAND TO GET
ERROR MESSAGE
Yes
No
Yes
No
Figure 3.5 - Self-Test: Basic Flow Diagram