Agilent Technologies 83491 User Manual

Agilent 83491/2/3A Clock Recovery Modules User’s Guide

Agilent Part No. 83491-90013 Printed in USA February 2000

Agilent Technologies Lightwave Division 1400 Fountaingrove Parkway Santa Rosa, CA 95403-1799, USA (707) 577-1400

Notice.

The information contained in this document is subject to change without notice. Companies, names, and data used in examples herein are fictitious unless otherwise noted. Agilent Technologies makes no warranty of any kind with regard to this material, including but not limited to, the implied warranties of merchantability and fitness for a particular purpose. Agilent Technologies shall not be liable for errors contained herein or for incidental or consequential damages in connection with the furnishing, performance, or use of this material.

Restricted Rights Legend.

Use, duplication, or disclosure by the U.S. Government is subject to restrictions as set forth in subparagraph (c) (1) (ii) of the Rights in Technical Data and Computer Software clause at DFARS 252.227-7013 for DOD agencies, and subparagraphs (c) (1) and (c) (2) of the Commercial Computer Software Restricted Rights clause at FAR 52.227-19 for other agencies.

Warranty.

This Agilent Technologies instrument product is warranted against defects in

material and workmanship for a period of one year from date of shipment. During the warranty period, Agilent Technologies will, at its option, either repair or replace products which prove to be defective. For warranty service or repair, this product must be returned to a service facility designated by Agilent Technologies. Buyer shall prepay shipping charges to Agilent Technologies and Agilent Technologies shall pay shipping charges to return the product to Buyer. However, Buyer shall pay all shipping charges, duties, and taxes for products returned to Agilent Technologies from another country.

Agilent Technologies warrants that its software and firmware designated by Agilent Technologies for use with an instrument will execute its programming instructions when properly installed on that instrument. Agilent Technologies does not warrant that the operation of the instrument, or software, or firmware will be uninterrupted or errorfree.

Limitation of Warranty.

The foregoing warranty shall not apply to defects resulting from improper or inadequate maintenance by Buyer, Buyersupplied software or interfacing, unauthorized modification or misuse, operation outside of the environmental specifications for the product, or improper site preparation or maintenance.

No other warranty is expressed or implied. Agilent Technologies specifically disclaims the implied warranties of merchantability and fitness for a particular purpose.

Exclusive Remedies.

The remedies provided herein are buyer's sole and exclusive remedies. Agilent Technolo-

gies shall not be liable for any direct, indirect, special, incidental, or consequential damages, whether based on contract, tort, or any other legal theory.

Safety Symbols.

CAUTION

The

caution

sign denotes a hazard. It calls attention to a procedure which, if not correctly performed or adhered to, could result in damage to or destruction of the product. Do not proceed beyond a caution sign until the indicated conditions are fully understood and met.

WAR NING

The

warning

sign denotes a hazard. It calls attention to a procedure which, if not correctly performed or adhered to, could result in injury or loss of life. Do not proceed beyond a warning sign until the indicated conditions are fully understood and met.

The instruction manual symbol. The product is marked with this warning symbol when it is necessary for the user to refer to the instructions in the manual.

The laser radiation symbol. This warning symbol is marked on products which have a laser output.

The AC symbol is used to indicate the required nature of the line module input power.

The ON symbols are

used to mark the positions of the instrument power line switch.

The OFF symbols

❍

are used to mark the positions of the instrument power line switch.

The CE mark is a registered trademark of the European Community.

The CSA mark is a registered trademark of the Canadian Standards Association.

The C-Tick mark is a registered trademark of the Australian Spectrum Management Agency.

This text denotes the

ISM1-A

instrument is an Industrial Scientific and Medical Group 1 Class A product.

Typographical Conventions.

The following conventions are used in this book:

Key type

for keys or text located on the keyboard or instrument.

Softkey type

for key names that are displayed on the instrument’s screen.

Display type

for words or characters displayed on the computer’s screen or instrument’s display.

User type

for words or charac-

ters that you type or enter.

Emphasis

type for words or characters that emphasize some point or that are used as place holders for text that you type.

General Safety Considerations

This product has been designed and tested in accordance with IEC Publication 61010-1, Safety Requirements for Electrical Equipment for Measurement, Control and Laboratory Use, and has been supplied in a safe condition. The instruction documentation contains information and warnings that must be followed by the user to ensure safe operation and to maintain the product in a safe condition.

WARNING

Light energy can radiate from the front panel Agilent 83492A and 83493A modules. The light emitted from these connectors is the slightly attenuated light that is input to the front-

INPUT

panel

If this instrument is not used as specified, the protection provided by the equipment could be impaired. This instrument must be used in a normal condition (in which all means for protection are intact) only.

To prevent electrical shock, disconnect the Agilent 83491/2/3A from mains before cleaning. Use a dry cloth or one slightly dampened with water to clean the external case parts. Do not attempt to clean internally.

This is a Safety Class 1 product (provided with a protective earthing ground incorporated in the power cord). The mains plug shall only be inserted in a socket outlet provided with a protective earth contact. Any interruption of the protective conductor inside or outside of the product is likely to make the product dangerous. Intentional interruption is prohibited.

No operator serviceable parts inside. Refer servicing to qualified personnel. To prevent electrical shock, do not remove covers.

For continued protection against fire hazard, replace line fuse only with same type and ratings, (type T 0.315A/250V for 100/120V operation and 0.16A/250V for 220/240V operation). The use of other fuses or materials is prohibited. Verify that the value of the linevoltage fuse is correct.

connector.

OUTPUT

connectors on

• For 100/120V operation, use an IEC 127 5×20 mm, 0.315 A, 250 V, Agilent

iii

General Safety Considerations

Technologies part number 2110-0449.

• For 220/240V operation, use an IEC 127 5×20 mm, 0.16 A, 250 V, Agilent Technologies part number 2110-0448.

CAUTION

Before switching on this instrument, make sure that the line voltage selector switch is set to the line voltage of the power supply and the correct fuse is installed. Assure the supply voltage is in the specified range.

This product is designed for use in Installation Category II and Pollution Degree 2 per IEC 1010 and 664 respectively.

VENTILATION REQUIREMENTS: When installing the product in a cabinet, the convection into and out of the product must not be restricted. The ambient temperature (outside the cabinet) must be less than the maximum operating temperature of the product by 4°C for every 100 watts dissipated in the cabinet. If the total power dissipated in the cabinet is greater than 800 watts, then forced convection must be used.

Always use the three-prong ac power cord supplied with this instrument. Failure to ensure adequate earth grounding by not using this cord may cause instrument damage.

connect ac power until you have verified the line voltage is correct.

Do not

Damage to the equipment could result.

This instrument has autoranging line voltage input. Be sure the supply voltage is within the specified range.

Electrostatic discharge (ESD) on or near input connectors can damage circuits inside the instrument. Repair of damage due to misuse is

covered under

not

warranty. Before connecting any cable to the electrical input, momentarily short the center and outer conductors of the cable together. Personnel should be properly grounded, and should touch the frame of the instrument before touching any connector.

General Safety Considerations iii

1 Installation

Installation 1-2

2Operation

Agilent 83491/2/3A Modules—At a Glance 2-2 Front-Panel Features 2-4 Block Diagrams 2-7 To Display a Signal 2-8 To Compensate for Module Insertion Loss 2-9 Using Probes with an Agilent 83491A 2-10

3 Specifications and Regulatory Information

Agilent 83491A Specifications 3-3 Agilent 83492A Specifications 3-4 Agilent 83493A Specifications 3-6 Agilent 83491/2/3A Operating Specifications 3-7 Declaration of Conformity 3-8

4 Reference

Front-Panel Optical Adapters 4-2 In Case of Difficulty 4-3 Error Messages 4-5 Electrostatic Discharge Information 4-8 Cleaning Connections for Accurate Measurements 4-10 Returning the Instrument for Service 4-20 Agilent Technologies Service Offices 4-23

Contents-1

To install the module 1-3 To connect cables to an Agilent 83492A 1-7

Installation

Agilent 83491/2/3A modules require that firmware revision A.06.25 or later be installed in the Agilent 83480A. If you wish to install the module in an Agilent 54750A digitizing oscilloscope, you must first install the Agilent 83480K communications firmware upgrade kit.

To check the Agilent 83480A’s firmware revision code

CAUTION

Press the

The firmware revision number is listed under the Frame section of the display.

Fiber-optic connectors are easily damaged when connected to dirty or damaged cables and accessories. The Agilent 83492A and 83493A front-panel input connectors are no exception. When you use improper cleaning and handling techniques, you risk expensive instrument repairs, damaged cables, and compromised measurements. Before you connect any fiber-optic cable to an Agilent 83492A or 83493A module, refer to “Cleaning Connections for Accurate Measurements” on page 4-10.

The circuits on electrical inputs and outputs can be damaged by electrostatic discharge (ESD). Therefore, avoid applying static discharges to any front or rear-panel electrical connector. Before connecting any coaxial cable to a frontpanel connector, momentarily short the center and outer conductors of the cable together. Avoid touching the front-panel connectors without first touching the frame of the instrument. Be sure that the instrument is properly earth-grounded to prevent buildup of static charge. Refer to “Electrostatic Discharge Information” on page 4-8.

Utility

key and then the

System config

softkey.

1-2

Installation

To install the module

Verify that all system components ordered have arrived by comparing the shipping forms to the original purchase order. Inspect all shipping containers. The shipment includes:

An Agilent 83491/2/3A Clock Recovery Module

❒

Fiber-optic adapter cable

❒

Two RF adapter cables

❒

Agilent 83491/2/3A User’s Guide (this book)

❒

If your shipment is damaged or incomplete, save the packing materials and notify both the shipping carrier and the nearest Agilent Technologies service office. Agilent Technologies will arrange for repair or replacement of damaged or incomplete shipments without waiting for a settlement from the transportation company. Notify the Agilent Technologies customer engineer of any problems.

Make sure that the serial number listed on the module’s rear-panel label matches the serial number listed on the shipping document.

Figure 1-1. Serial number label

Install the Agilent 83491/2/3A module into the Agilent 83480A mainframe’s left slot. Finger-tighten the knurled screw on the front panel of the plug-in module to ensure that the module is securely seated in the mainframe.

(Agilent 83492/3A module only)

(Agilent 83491A module only)

Note

Installing the module into the left slot ensures that the supplied adapter cable will fit. See Figure 1-2.

1-3

Installation

Figure 1-2. Position of modules in the mainframe

Clean all optical interfaces as described in “Cleaning Connections for Accurate

Measurements” on page 4-10, before making measurements

Perform the following steps if you’re installing an Agilent 83492/3A module:

Unscrew and remove the fiber-optic adapter that is located on the optical

module’s front-panel optical input connector.

WARNING

Connect the adapter that was removed in the previous step onto the Agilent 83492/3A module’s front-panel

Input

connector.

On Agilent 83492A module’s, the input connector used depends on the wavelength of the input signal. Refer to “To connect cables to an Agilent 83492A” on page 1-7.

Connect the supplied adapter cable as shown in Figure 1-3.

Light energy can radiate from the front panel

OUTPUT

connectors on Agilent 83492A and 83493A modules. The light emitted from these connectors is the slightly attenuated light that is input to the front-

INPUT

panel

Turn on the Agilent 83480A, and connect a modulated signal to the Agilent 83491/2/3A module’s

1-4

connector.

Input

connector.

Figure 1-3. The adapter cable

Installation

CAUTION

Agilent 83491A Modules: Maximum safe signal input level is ±5V. The input circuits can also be damaged by electrostatic discharge (ESD). Before connecting any coaxial cable to the connectors, momentarily short the center and outer conductors of the cable together. Avoid touching the front-panel input connectors without first touching the frame of the instrument. Be sure that the instrument is properly earth-grounded to prevent buildup of static charge.

Agilent 83492/3A Modules:

On the Agilent 83480A, press the

trigger 2

select

On the Agilent 83491/2/3A module, repeatedly press the

(the Agilent 83491/2/3A module) for the trigger source.

Maximum safe signal input level is +3 dBm.

Trigger

key and then the

Source

softkey. Then,

SELECT

key until a front-panel light indicates the data rate of the signal. See Figure 1-4 on

page 1-6.

Green and red data-rate lights

The data-rate indicator lights change color between red and green to show which data rate is selected. A red light does

indicate a problem. A red light shows that the adja-

not

cent red data rate label is selected. A green light shows that the adjacent green data rate label is selected. Repeatedly pressing the SELECT key cycles through the selections in one color before switching to the opposite color. On Agilent 83491A modules for example, the first selection cycle shows 155 Mb/s selected. The second section cycle shows 1062 Mb/s selected.

1-5

Installation

Figure 1-4. Front-panel lights

Clock

Unlocked

Data

and

is off.

light

outputs on an oscilloscope. Waveforms should be

Confirm that the

Observe the present. The instrument is now ready for you to begin making measurements.

1-6

Installation

To connect cables to an Agilent 83492A

On Agilent 83492A modules, the front-panel fiber-optic connectors reverse input and output roles depending on the wavelength of the signal. Signals in the 750 nm to 860 nm wavelength range are input to the left connector and output from the right connector. Signals in the 1000 nm to 1600 nm wavelength range are input to the right connector and output from the left connector.

Figure 1-5. Input and output connections versus wavelength

1-7

Agilent 83491/2/3A Modules—At a Glance 2-2 Front-Panel Features 2-4 Block Diagrams 2-7 To Display a Signal 2-8 To Compensate for Module Insertion Loss 2-9 Using Probes with an Agilent 83491A 2-10

To compensate for a passive probe 2-11 To compensate an Agilent 54701A active probe 2-11 To compensate for other devices 2-12

Operation

Agilent 83491/2/3A Modules—At a Glance

The Agilent 83491/2/3A are designed to operate in an Agilent 83480A digital communications analyzer. These modules recover clock and data information at standard telecom and datacom rates. The resulting trigger signal is made available to the Agilent 83480A mainframe via a connector located on the module’s rear-panel. An external front-panel cable passes the data signal, with some insertion loss, to the receiver module.

Table 2-1. Module Features

Agilent Module

83491A

83492A

83493A

Input Connector Selectable Rates (Mb/s)

Ω

electrical

Multimode fiber (62.5/125

Single-mode fiber (9/125

155, 622, 1060, 1250, 2120, 2488, 2500

155, 622, 1250, 2488, 2500

Figure 2-1. An Agilent 83493A installed in an Agilent 83480A mainframe

2-2

Operation

Agilent 83491/2/3A Modules—At a Glance

WARNING

Light energy can radiate from the front panel

OUTPUT

connectors on Agilent 83492A and 83493A modules. The light emitted from these connectors is the slightly attenuated light that is input to the front-

INPUT

panel

connector.

Use with Agilent 71603B or 71612B Error Performance Analyzers

The front-panel

Data

and

Clock

outputs provide electrical recovered clock and regenerated data signals for simultaneous testing with other instruments, such as the Agilent 71603B or 71612B error performance analyzers.

Multimode module and single-mode reference receivers

Agilent Technologies does

recommend using the Agilent 83492A multi-

not

mode module with single-mode reference receivers such as the Agilent 83481A, 83482A, or 83485A,B modules. Connecting multimode to single-mode fibers causes large reflections and insertion loss because of the reduction of the optical fiber’s core from 62.5 µm to 9 µm.

Single-mode module and multimode reference receivers

It is acceptable to use an Agilent 83493A single-mode module with a multimode reference receiver such as the Agilent 83486A module. This is true provided that single-mode fiber is connected to the Agilent 83493A module’s front-panel

INPUT

connector.

What you won’t find on these modules....

Unlike other modules designed to be used with the Agilent 83480A digital communications analyzer, the Agilent 83491/2/3A modules do not include Channel keys or menus. Also, there are no GPIB programming commands for these modules.

2-3

Operation

Front-Panel Features

SELECT

Figure 2-2. Agilent 83491/2/3A front panels

key Pressing this key changes the modulation rate of the input signal. The recov-

ered and retimed clock trigger is sent to the mainframe. The selection is a bypass mode where the data stream directly triggers the mainframe. Refer to “Block Diagrams” on page 2-7 to view a schematic of the normal and bypass paths.

2-4

Trigger On Data

+ 42 hidden pages