80C14
xx
ZZZ
Optical Sampling Module
User Manual
*P071295500*
071-2955-00
xx
80C14
ZZZ
Optical Sampling Module
User Manual
www.tektronix.com
071-2955-00
Copyright © Tektronix. All rights reserved. Licensed software products are owned by Tektronix or its subsidiaries
or suppliers, and are protected by national copyright laws and international treaty provisions.
Tektronix products are covered by U.S. and foreign patents, issued and pending. Information in this publication
supersedes that in all previously published material. Specifications and price change privileges reserved.
TEKTRONIX and TEK are registered trademarks of Tektronix, Inc.
Contacting Tektronix
Tektronix, Inc.
14150 SW Karl Braun Drive
P.O. Box 500
Beaverto
USA
For product information, sales, service, and technical support:
n, OR 97077
In North America, call 1-800-833-9200.
Worl dwid e, visi t www.tektronix.com to find contacts in your area.
Warranty
Tektronix warrants that this product will be free from defects in materials and workmanship for a period of three
(3) years from the date of shipment. If any such product proves defective during this warranty period, Tektronix, at
its option, either will repair the defective product without charge for parts and labor, or will provide a replacement
in exchange for the defective product. Parts, modules and replacement products used by Tektronix for warranty
work may be n
the property of Tektronix.
ew or reconditioned to like new performance. All replaced parts, modules and products become
In order to o
the warranty period and make suitable arrangements for the performance of service. Customer shall be responsible
for packaging and shipping the defective product to the service center designated by Tektronix, with shipping
charges prepaid. Tektronix shall pay for the return of the product to Customer if the shipment is to a location within
the country in which the Tektronix service center is located. Customer shall be responsible for paying all shipping
charges, duties, taxes, and any other charges for products returned to any other locations.
This warranty shall not apply to any defect, failure or damage caused by improper use or improper or inadequate
maintenance and care. Tektronix shall not be obligated to furnish service under this warranty a) to repair damage
result
b) to repair damage resulting from improper use or connection t o incompatible equipment; c) to repair any damage
or malfunction caused by the use of non-Tektronix supplies; or d) to service a product that has been modified or
integrated with other products when the effect of such modification or integration increases the time or difficulty
of servicing the product.
THIS WARRANTY IS GIVEN BY TEKTRONIX WITH RESPECT TO THE PRODUCT IN LIEU OF ANY
OTHER WARRANTIES, EXPRESS OR IMPLIED. TEKTRONIX AND ITS VENDORS DISCLAIM ANY
IMPLIED WARRANTIES OF MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE.
TRONIX' RESPONSIBILITY TO REPAIR OR REPLACE DEFECTIVE PRODUCTS IS THE SOLE
TEK
AND EXCLUSIVE REMEDY PROVIDED TO THE CUSTOMER FOR BREACH OF THIS WARRANTY.
TEKTRONIX AND ITS VENDORS WILL NOT BE LIABLE FOR ANY INDIRECT, SPECIAL, INCIDENTAL,
OR CONSEQUENTIAL DAMAGES IRRESPECTIVE OF WHETHER TEKTRONIX OR THE VENDOR HAS
ADVANCE NOTICE OF THE POSSIBILITY OF SUCH DAMAGES.
[W4 – 15AUG04]
btain service under this warranty, Customer must notify Tektronix of the defect before the expiration of
ing from attempts by personnel other than Tektronix representatives to install, repair or service the product;
Table of Contents
General Safety Summary ......................................................................................... iv
Environmental Considerations ................................................................................... vi
Preface ............................................................................................................. vii
Specificati
Manual Structure............................................................................................. vii
Related Documentation ..................................................................................... viii
Getting Started ..... . ... . . ..... . ..... . ... . . . .... . ..... . ..... . ... . . ..... . ..... . ... . . . .... . ..... . ..... . ... . . ..... . ..... 1
Instrument Requirements .................. ................................ ................................ ... 1
Module Features ............................................................................................... 1
Options
Installation ............................. ................................ .................................. ....... 4
Operating Basics.................................................................................................... 7
Usage....................... ................................ .................................. ................... 7
System Interaction............................................................................................. 8
Front Panel Controls............................ ................................ ............................... 9
Comm
Programmer Interface Commands .............................. ................................ ............ 12
User Adjustments ............................... ................................ .............................. 12
Optimizing Measurement Accuracy .............................. .................................. ........ 12
Cleaning ....................................................................................................... 16
Reference ............... .................................. ................................ .......................... 19
velength, Filter, and Bandwidth Selection . . ..... . ... . . ..... . ..... . ..... . ..... . .... . . .... . ..... . ..... . . 19
Wa
Clock Recovery ........................... ................................ .................................. .. 19
Optical Bandwidth............................................................................................ 19
Glossary
Index
ons................................................................................................. vii
and Accessories ...................................................................................... 3
ands from the Main Instrument Front Panel ....................................................... 10
80C14 Optical Sampling Module User Manual i
Table of Contents
List of Figure
Figure 1: Module compartments.................................................................................. 5
Figure 2: Co
Figure 3: 80C14 optical module front panel..................................................................... 9
Figure 4: Vertical Setup dialog boxes (DSA8200)............................................................. 11
nnecting optical cables correctly............ ................................ ....................... 7
s
ii 80C14 Optical Sampling Module User Manual
List of Tables
Table 1: 80C14 module features.................................................................................. 2
Table 2 : St a
Table 3: Available 80C14 options ................................................................................ 3
Table 4: Optional accessories ..................................................................................... 3
ndard accessories ..................................................................................... 3
Table of Contents
80C14 Optical Sampling Module User Manual iii
General Safety Summary
General Safet
To Avoid Fire or Personal
Injury
ySummary
Review the fo
this product or any products connected to it.
To avoid pot
Only qualified personnel should perform service procedures.
While using this product, you may need to access other parts of a larger system.
Read the safety sections of the other component manuals for warnings and
cautions r
Ground the product. This product is indirectly grounded through the grounding
conductor of the mainframe power cord. To avoid electric shock, the grounding
conductor must be connected to earth ground. Before making connections to
the input or output terminals of the product, ensure that the product is properly
ground
Observe all terminal ratings. To avoid fire or shock hazard, observe all ratings
and ma
information before making connections to the product.
The i
ed.
nputs are not rated for connection to mains or Category II, III, or IV circuits.
llowing safety precautions to avoid injury and prevent damage to
ential hazards, use this product only as specified.
elated to operating the system.
rkings on the product. Consult the product manual for further ratings
Do not apply a potential to any terminal, including the common terminal, that
eeds the maximum ratingofthatterminal.
exc
Do not operate without covers. Do not operate this product with covers or panels
oved.
rem
Do not operate with suspected failures. If you suspect that there is damage to this
oduct, have it inspected by qualified service personnel.
pr
Avoid exposed circuitry. Do not touch exposed connections and components when
ower is present.
p
Wear eye protection. Wear eye protection if exposure to high-intensity rays or
laser radiation exists.
Do not operate in wet/damp conditions.
Do not operate in an explosive atmosphere.
Keep product surfaces clean and dry.
Provide proper ventilation. Refer to the manual's installation instructions for details
on installing the product so it has proper ventilation.
iv 80C14 Optical Sampling Module User M anual
General Safety Summary
TermsinThisManual
Symbols and Terms on the
Product
These terms may
WAR NI NG . Warning statements identify conditions or practices that could result
in injury or loss of life.
CAUTION. Caution statements identify conditions or practices that could result in
damage to this product or other property.
These terms may appear on the product:
DANGER in
the marking.
WARNING
read the marking.
CAUTIO
The following symbol(s) may appear on the product:
appear in this manual:
dicates an injury hazard immediately accessible as you read
indicates an injury hazard not immediately accessible as you
N indicates a hazard to property including the product.
80C14 Optical Sampling Module User Manual v
Environmental Considerations
Environmenta
Product End-of-Life
Handling
Restriction of Hazardous
Substances
l Considerations
This section
Observe the following guidelines when recycling an instrument or component:
Equipment Recycling. Production of this equipment required the extraction and
use of natu
harmful to the environment or human health if improperly handled at the product’s
end of life. In order to avoid release of such substances into the environment and
to reduce the use of natural resources, we encourage you to recycle this product
in an appropriate system that will ensure that most of the materials are reused or
recycled appropriately.
This product has been classified as Monitoring and Control equipment, and is
outside the scope of the 2002/95/EC RoHS Directive.
provides information about the environmental impact of the product.
ral resources. The equipment may contain substances that could be
This symbol indicates that this product complies with the applicable European
Union requirements according to Directives 2002/96/E C and 2006/66/EC
on waste electrical and electronic equipment (WEEE) and batteries. For
information about recycling options, check the Support/Service section of the
Tektronix Web site (www.tektronix.com).
vi 80C14 Optical Sampling Module User Manual
Preface
Specifications
This manual for the 80C14 Optical Sampling Module includes the following
information:
Key features
How to install the module
How to control signal acquisition, processing, and input/output of information
Go to the Tektronix manuals Web site (www.te k.c om/manuals) to locate the latest
version of this document.
Specifications are located in the specifications and performance verification
document for your main instrument. You can download these manuals from the
Tektronix Web site (www.tek.com/manuals).
To meet measurement specifications:
The instrument was calibrated/adjusted at an ambient temperature between
+20 °C and +30 °C.
Manual Structure
The instrument has been operating continuously for 20 minutes within the
operating temperature range specified.
Vertical compensation has been performed with the module installed in the
same compartment used when the compensation was performed. Ambient
temperature must be within ± 2 °C of the compensation temperature.
The instrument must be in an environment with temperature, altitude,
humidity, and vibration within the operating limits described in the
specifications.
This manual contains the following chapters:
Getting Started shows you how to configure and install your optical module.
Operating Basics describes controlling the module using the front panel and
the instrument user interface.
Reference provides information on wavelength selection, clock recovery,
and optical bandwidth.
80C14 Optical Sampling Module User Manual vii
Preface
Related Documentation
This document covers installation and usage of the sampling module and its
features. For information about the main instrument in which the sampling
module is installed, refer to the user documents and online help provided with
your main instrument.
viii 80C14 Optical Sampling Module User Manual
Getting Started
The 80C14 Series Optical Sampling Module is a high-performance optical
module that supports high bandwidth telecom and datacom standards including
16 GFC Fibre C
compatible with the following instruments (mainframes):
hannel and 14.063 Gb/s Infiniband. The 80C14 Series module is
Instrument Requirements
Contact Tektronix Customer Support for information on how to upgrade your
instrument to meet these requirements.
Module Features
Table 1 lists the 80C14 optical module features. (See Table 1 on page 2.)
A figure in the Operating Basics section shows the module controls, connectors,
and indicators. (See Figure 3 on page 9.)
DSA8300 Dig
DSA8200 Digital Signal Analyzer
CSA8000, CSA8000B, and CSA8200 Communications Signal Analyzers
TDS8000, TDS8000B, and TDS8200 Digital Sampling Oscilloscopes
TekScope application software version 5.1 or greater. Select Help > About
from the TekScope application Help menu to show your current version.
Microsoft Windows XP operating system.
ital Serial Analyzer
80C14 Optical Sampling Module User Manual 1
Getting Started
Table 1: 80C14 m
Feature Description
Number of inpu
Effective wa
Supported s
filtering rates
velength range
tandards or data
odule features
t channels
1
1
700 nm to 1650 nm
8GFC (8.500
Gb/s)
OC-192/STM-64 (9.953 Gb/s)
10GBase-W (9.953 Gb/s)
10GBase-R (
10.31 Gb/s)
40GBase-R4 (10.31 Gb/s)
100GBase-SR10 (10.31 Gb/s)
10GFC (10.
52 Gb/s)
ITU-T G.975 FEC (10.664 Gb/s)
ITU-T G.709 (10.709 Gb/s)
10 GbE FEC (
11.1 Gb/s)
10GFC FEC (11.3 Gb/s)
Super FEC (12.5 Gb/s)
16GFC (14
.025 Gb/s)
14G Infiniband FDR (14.0625 Gb/s)
optical bandwidth at
Typical
>14GHz
optical connector
Clock recovery support Clock recovery supported with the use of the CR175A
or CR286A Clock Recovery instrument (purchased
tely)
separa
Absolute maximum
tructive optical input
nondes
2
2 mW average power (1350 nm, 1550 nm)
4mWave
rage power (850 nm)
10 mW peak power for 60 ms.
Internal fiber diameter 62.5 mm/125 μm multimode mode
3
Optical return loss > 14 dB for multimode fiber > 24 dB for single-mode fiber
Output zero < 1 μW immediately after dark calibration ±2% (vertical
set)
off
Independent channel deskew
fset capability at front of
Of
Sta
andard
St
ndard
module
wer meter
Po
1
Some values in the table are typical.
2
he optical input powers below nondestructive levels may exceed saturation and compression limits of the module.
T
3
Compatible with single-mode fiber of equal or smaller diameter.
Standard
2 80C14 Optical Sampling Module User Manual
Getting Started
Options and Ac
Standard Acc
essories
Options
cessories
This section lists the standard and optional accessories available for the sampling
modules.
The following acc essories are shipped with the module:
Table 2: Standard accessories
Item Part number
Certificate of Traceable Calibration for
product at first shipment
SMA male 50 Ω termination (installed, one
for each b
Fiber cleaning kit 020-2494-XX
The following table lists available sampling module options:
Table 3: Available 80C14 options
Option Description
Option C3 Three years of calibration service
Option C5 Five years of calibration service
Option D1 Calibration data report
Option D3 Three years of calibration data reports (requires Opt. C3)
Option D5 Five years of calibration data reports (requires Opt. C5)
Option R3
Option R5 Extended repair warranty to five years
uffered electrical output connector)
Extended repair warranty to three years
Not ordera
015-1022-XX
ble
ptional Accessories
O
You can order the following accessories for use with the sampling m odules:
Table 4: Optional accessories
tem
I
D4/PC Universal Optical Input (UCI) adapter
Biconic UCI adapter
FC/PC U CI adapter, APC-108
SMA 2.5 UCI adapter
SC/PC UCI adapter
DIN/PC UCI adapter
DIAMOND 2.5 UCI adapter
SMA UCI adapter
DIAMOND 3.5 UCI adapter
art number
P
119-4514-XX
119-4515-XX
119-5115-XX
119-4517-XX
119-5116-XX
119-4546-XX
119-4556-XX
119-4557-XX
119-4558-XX
80C14 Optical Sampling Module User Manual 3
Getting Started
Table 4: Optional accessories (cont.)
Item Part number
ST/PC UCI adapter
3.5 male to 3.5 female SMA
Slip-on SMA connector
CSA8000 & TDS8000 Series Service Manual
DSA8200 Service Manual
80C14 Series Optical Sampling Module User
Manual (this document)
119-4513-XX
015-0552-XX
015-0553-XX
071-0438-XX
071-2049-XX
071-2955-XX
Installation
Electrostatic Discharge
See the
Tektronix Web site for the current list of optional accessories.
CAUTION. The electrical data outputs on the optical module are subject to
damage from electrostatic discharge (ESD). To prevent damage from electrostatic
harge, observe the followig guidelines:
disc
Store the module, with the supplied SMA terminations installed, in a static-free
tainer, such as the shipping container. Whenever you move the optical module
con
from one instrument to another, use a static-free container to carry the optical
module.
Be sure to only operate the optical module in a static-controlled environment
(grounded conductive table top, wrist strap, floor mat, and ionized air blower).
Always use a grounded wrist strap (provided with your instrument) when
installing, removing, or handling an optical module or making connections.
Discharge to ground any electrostatic charge that may be present on cables before
attaching the cable to the optical module.
Circuitry in the optical module is very susceptible to damage from overdriven
signals. Verify that the optical signal is within acceptable power levels for the
module before connecting the signal to the module.
4 80C14 Optical Sampling Module User Manual
Getting Started
Correct Module
Module Locations
Handling
Guidelines
CAUTION. To avoid damaging your optical module, take the following
precautions
Never install or remove a module when the instrument is powered on (front-panel
On/Standby power switch is ON).
Do not drop the module since damage and misalignment of the photodiode optical
assembly can result. Store the module in a secure location when not in use.
Place the protective cap(s) on the optical and electrical input connectors when
the module is not in use.
To prevent loss of optical power or damage to the optical connectors, keep the
connectors clean at all times.
Check that all connectors, jumpers, and protective caps are clean before
connecting them to the module. (See page 16, Cleaning the Optical Connectors.)
The optical modules fit in the large upper module slots in supported instruments,
such as the DSA8300. The large compartments support single channel modules,
while the small compartments support single or dual channel modules. Eight of
the 10 inputs are usable at one time. (See Figure 1.)
:
Figure 1: Module compartments
80C14 Optical Sampling Module User Manual 5
Getting Started
Installing a Module
At least one mod
NOTE. Installing a large module in either large compartment disables some of
the small compartment channels. Refer to the instrument Online Help about
compartment interaction.
1. Power off the instrument using the fro nt-panel On/Standby power switch.
2. Plug the grounding strap into the instrument ground connector, and place the
ground strap on your wrist, with contact to skin.
3. Turn the hold-down screws all the way counterclockwise so that they are
completely out and the module retaining tab is flush with the edge of the
module.
4. Insert the module into a compartment and slowly push it in with firm pressure
until it is seated.
5. Turn the hold-down screws clockwise to lock the module in place.
6. Once you have installed the module, power on the instrument. Verify that
the module passes power-on tests.
ule must be installed in an instrument to acquire signals.
Removing a Module
NOTE. After first installing a sampling module(s) or after moving a sampling
module from one compartment to another, and after the 20-minute instrument
warm-up period, select Utilities > Compensation to run the compensation tool
to ensure optimum measurement accuracy. You must also run a compensation
if an extender is installed, changed, or removed from a module. (See page 12,
Optimizing Measurement Accuracy.)
After running Compensation, save the new values to retain them; otherwise they
are lost when powering off the instrument.
1. Power off the instrument using the fro nt-panel On/Standby power switch.
2. Plug the grounding strap into the instrument ground connector, and place the
ground strap on your wrist, with contact to skin.
3. Turn the hold-down screws all the way counterclockwise so that they are
completely out and the module retaining tab is flush with the edge of the
module.
4. Slide the appropriate large module ejector lever sideways to unseat the
module from the mainframe connector.
5. Pull on the hold-down screws to remove the module from the slot.
6. Handle the module appropriately (move to another slot in the instrument or
place in a static-protected environment to transport or store the module).
6 80C14 Optical Sampling Module User Manual
Operating Basics
Usage
This section contains optical module signal connection and operation information.
Handle your optical module carefully at all times.
Connecting Optical Signals
Take care to preserve the integrity of the connectors by keeping them free of
contamination. (See page 16, Cleaning the Optical Connectors.)
The input of the 80C14 module can couple to any single-mode dimension
or multimode dimension not exceeding a core diameter/cladding diameter of
62.5/125 mm. Use UCI (universal connector interface) series adapters to couple
alternate cable types to the optical module. Refer to the Tektronix Web site for
details.
Attach the fiber optic cable to the optical input receptacle as follows:
CAUTION. Do not insert the connector into the UCI adapter at an angle. Do
not insert the connector and then rotate to line up the key with the slot. Either
action can damage the UCI adapter.
1. Line up the key with the slot in the UCI adapter before inserting.
Figure 2: Connecting optical cables correctly
2. Firmly push the cable connector or adapter into the interface ferrule until it
reaches the stop. Do not twist the cable while inserting.
80C14 Optical Sampling Module User Manual 7
Operating Basics
Attenuating Optical
Signals
3. Firmly tighten
the cable connector or the adapter shell. Tighten with finger
pressure only.
4. To remove, loo
sen the cable connector or adapter shell.
You may need to attenuate the optical input power to an appropriate level for the
module. The 80C14 absolute maximum optical signal levels are:
4 mW average optical power at 850 nm
2 mW average optical power at 1350 nm and 1350 nm
10 mW peak at wavelength of highest responsivity
CAUTION. To avoid damaging the optical input of the module, attenuate the input
optical signal to the absolute maximum optical signal levels listed above.
NOTE. The 80C14 module can have a somewhat deteriorated response for signals
greater than 800 μW
(1310 nm and 1550 nm) and 1300 μW
p-p
(850 nm).
p-p
NOTE. Optical sampling modules may have dynamic ranges exceeded without
obvious visual indication on the waveform because the overloaded signal output
of the photodetector m ay still be within the dynamic range of the internal
trical sampler. To ensure accurate measurements, make sure that input signal
elec
levels are within valid ranges for the module.
System Interaction
Your optical module is a part of a larger instrument system. Most optical module
functions are controlled automatically by the main instrument. These include such
things as vertical scaling and horizontal sampling rate. You do not directly control
hese parameters; they are controlled for you as you perform tasks on the main
t
instrument. The parameters that you control from the optical module front panel
are explained in the Front Panel Controls section.
An additional optical module function that you control from the main instrument
is external channel attenuation. External Attenuation lets you enter a number
representing any external attenuation you have added to a channel.
8 80C14 Optical Sampling Module User Manual
Operating Basics
Front Panel Co
Channel Selection
ntrols
The following figure shows the 80C14 front panel. (See Figure 3.)
Each channel has a SELECT channel button and an amber channel light. The
button operates as follows:
If the amber channel light is on, the channel is acquiring a waveform.
If you push the channel button and the channel is not being acquired (for
any channel or math waveform), then the instrument activates (turns on) the
channel.
If you push the button and the channel is active as a channel waveform, then
the instrument selects the channel waveform.
If the channel waveform is already selected when you push the channel
button, the instrument turns the channel off.
Figure 3: 80C14 optical module front panel
Optical Input Connector
80C14 Optical Sampling Module User Manual 9
The optical input connector uses a universal connector interface (UCI) that allows
use of many standard fi ber-optic female connector styles. Some of the standard
UCI interfaces supported are FC, ST, SC, and DIN. (Refer to a current Tektronix
catalog for details. Go to www.tek.com to download the latest catalog.)
Operating Basics
Outputs
Hold-Down Screws
The 80C14 modul
purposes, route this signal to the input of an CR175A or CR286A Electrical Clock
Recovery instrument.
CAUTION. Electrostatic discharge (ESD) will cause permanent damage to
electrical outputs. Adhere to standard ESD handling precautions when using the
outputs. In particular, make sure to discharge to ground any cables or connectors
before atta
the center pin of the coaxial cable to a grounded conductor (such as the outside
ground conductor of the coaxial data output connector) just before connecting
the cable to the module.
NOTE. Use 50 Ω terminations, provided with your optical module, on all unused
electri
Hold-down screws attach the module to the main instrument. Once the hold-down
screws are loosened, use the module slot eject levers to remove the module from
apowe
the direction that the latch is pointing.
NOTE. Do not pull on module connectors to remove a module; always use the
hold-down screws to pull the module out far enough for you to hold the module
and remove it from the instrument.
ching them to the BUFFERED outputs. To discharge a cable, touch
cal outputs.
red-down main instrument. Indicators on the hold-down screws point in
e provides buffered electrical signal outputs. For clock recovery
Commands from the Main Instrument Front Panel
e Vertical Setup dialog box lets you toggle between the basic and optical
Th
module controls. (See Figure 4.) The DSA8300 controls are similar.
u first select the channel you want to set in the Waveform section of the dialog
Yo
box. Then you select the Setup Wavelength, Filter, Bandwidth, or Compensate
controls in the dialog box to change those settings or to initiate a compensation.
Optical modules with the clock recovery option also have source and rate controls
in the Trigger dialog box.
10 80C14 Optical Sampling Module User Manual
Operating Basics
Detailed infor
instrument.
mation on these dialog boxes is found in the Online Help of your
Figure 4: Vertical Setup dialog boxes (DSA8200)
80C14 Optical Sampling Module User Manual 11
Operating Basics
Programmer In
terface Commands
The remote programming commands for all sampling modules are documented in
the Programmer Guide acce ssible from the instrument Help menu.
User Adjustments
All optical module setups, parameters, and adjustments are controlled by the
main instr
ument. To save, recall, or change any module settings, use the
main-instrument menus or front-panel controls. Consult the Online Help for
your main instrument.
Optimizing Measurement Accuracy
Performing the following procedures to increase (or maintain) the measurement
accuracy of the optical module:
Run Vertical Compensation
Clean the Optical Connectors
Run Da
rk-Level and User Wavelength Gain Compensations
Perform Vertical
Compensation
Overview Step Control elements and resources
requisites
Pre
Access the
compensation
outines
r
1. The instrument must have the sampling module(s)
to be compensated installed. The acquisition system
uld be set to run continuously.
sho
2. Dust covers must be in place on all optical module
channels (or otherwise eliminate the optical input)
less directed otherwise by on-screen instructions.
un
3. Power on the instrument and allow a 20-minute
warm-up before doing this procedure.
4. Select Utilities > Compensation from the application
enu bar.
m
Performing a vertical compensation optimizes the accuracy of automatic
measurements. This procedure uses internal routines to optimize the signal
ical offset, gain, and linearity.
vert
See the instrument user documentation and
line help for details on operating the instrument
on
controls.
12 80C14 Optical Sampling Module User Manual
Overview Step Control elements and resources
Select w hat to
compensate
5. The Compensation dialog box lists the main instrument
(mainframe) and installed sampling modules. The
temperature c
also listed.
6. Wait until the Status for all items changes from Warm
Up to Pass, Fa
hange from the last compensation is
il,orComp Req'd.
Operating Basics
Save
compensation
values
Select w hat to
compensate
Run
compensation
Verify that the
compensation
routines pass
Compensation
fail actions
Save
compensation
values
7. Under Select Action, click Compensate and Save.
8. Select what to compensate:
DSA8200: From the top pulldown list, choose All
(default selection) to compensate the main instrument
and all installed modules .
DSA8300: You will need to run two compensations to
compensate the mainframe and all modules. Select
Mainframe and run the compensation, then select All
Modules and run the compensation.
9. Click Execute to begin the compensation.
10. Follow any on-screen instructions to disconnect
inputs and install terminations; be sure to follow static
precautions when following these instructions.
11. The compensation may take several minutes to
complete. Verify that Pass appears as Status for the
main instrument and for all sampling modules listed
in the Compensation dialog box when compensation
completes.
12. If Fail appears as theStatus, rerun the compensation.
If Fail status continues after rerunning compensation,
and the instrument has passed the 20-minute warm-up
period, the module or main instrument may need
service. Contact Tektronix C ustomer Service.
13. Click the Save option button under Select Action. Click
the Execute button to save the compensation values.
Make sure to save the compensation values.
In-memory compensation values are lost when you
power off the instrument.
80C14 Optical Sampling Module User Manual 13
Operating Basics
Perform Dark-Level and
User Wavelength Ga in
Compensations
Perform a darkratio and other optical automatic measurements. Perform a User Wavelength Gain
compensation to optimize an optical channel to your custom input signal.
level compensation to maximize the accuracy of the extinction
Use the following procedure to perform either compensation.
NOTE. These procedures compensate the selected module and its current
bandwidth and filter selection. The compensation values are not saved when
powering off the instrument.
This procedure applies only to optical modules.
NOTE. This procedure shows images from the DSA8200 instrument user interface.
The DSA8300 UI, although different in appearance, has a similar UI layout as the
DSA8200 for most functions.
Overvie
Prerequisites 1. Install the optical sampling module in the instrument.
w
To perfo
rm optical compensations
acquisition system to run continuously.
Set the
Control
elements and resources
ct the
Sele
waveform
Access the
dark-level
compensation
2. Use the Vertical buttons to select the channel to
ensate.
comp
3. Click Setup > Vertical.
See the instrument user documentation and
online help for details on operating the instrument
ols.
contr
14 80C14 Optical Sampling Module User Manual
Overview To perform optical compensations Control elem e nts and resources
Run the
dark-level
compensation
Run the use
wavelength
gain
compensa
tion
4. Click the Dark Level button under Compensation.
Follow the on-screen instructions.
5. Repeat steps 2
channels that you want to compensate.
If any of the following settings or conditions change after
performing a
compensation to maintain the specified accuracy.
Trigger rate setting
Vertical offset setting
Filter or bandwidth setting
Ambient temperature change of more than 1 °C
r
You can opt
an optical channel:
6. In the Vert Setup dialog box, click the User
ionally use a custom input signal to compensate
Waveleng
the i nstructions on screen.
through 4 for any additional optical
dark level compensation, perform another
th Gain button under Compensation. Follow
Operating Basics
In the User Wavelength Gain Compensation dialog
box, set the wavelength and power of the signal to
ed to the channel.
be appli
7. You must connect an optical signal to the module input
with a precisely known amount of optical power. Use
pendently calibrated average optical power
an inde
meter to precisely measure this power. Then connect
the signal to the module using the s ame fiber cables.
8. Click t
9. Repeat steps 2, 6, and 7 for any additional optical
he OK button to execute the compensation.
channels that you want to compensate.
80C14 Optical Sampling Module User Manual 15
Operating Basics
Cleaning
Exterior
The case of the module keeps dust out and should not be opened. Confine cleaning
to the front panel of the module. To clean the case, remove the module from the
main instrum
of the module. (See page 4.)
WARNING. To prevent injury, power off the instrument and disconnect it from line
voltage before performing any cleaning.
Clean the exterior surfaces of the module with a dry lint-free cloth or a soft-bristle
brush. If any dirt remains, use a damp cloth or swab dipped in a 75% isopropyl
alcohol solution. Use a swab to clean narrow spaces around controls and
connectors. Do not allow moisture inside the module. Do not use abrasive
compou
CAUTION. To prevent damage, avoid the use of chemical cleaning agents which
might damage the plastics in this instrument. Use a 75% isopropyl alcohol
solution as a cleaner and rinse with deionized water. Use only deionized water
when cleaning the menu buttons or front-panel buttons. Before using any other
type of cleaner, consult your Tektronix Service Center or representative.
ent but first read the entire Installation procedure for proper handling
nds on any part of the chassis that may damage the chassis.
Interior
eaning the Optic al
Cl
Connectors
Do not open the module case. There are no user serviceable components inside
the module and cleaning the interior is not required.
Small dust particles and oils can easily conta minate optical connectors and reduce
or block the signal. Take care to preserve the integrity of the connectors by
keeping them free of contamination.
AUTION. To prevent loss of optical power or damage to the optical connectors,
C
keep the connectors clean at all times.
To reduce the need for cleaning, immediately replace protective caps on the
optical connectors when not in use.
16 80C14 Optical Sampling Module User Manual
Operating Basics
Overview To clean t
s
Supplie
required
Remove UCI
adapter
1. One comp
number 118-1068-01.
One FIS cassette cleaner, (such as FI-6270)
or
one FIS tape dispenser cleaner (such as FI-7111).
2. Loosen the UCI adapter and remove it. This exposes
the male fiber end-face behind the UCI connector.
Use the followi
ng items to clean optical connectors:
Dry, clean, and dust-free compressed air
Fiber cleaning cassette and/or tape dispenser cleaner
Pipe cleaner
CAUTION. Clean both ferrule endfaces with a dry cloth tape cleaner (cassetted
or in a dispenser).
For safe and effective cleaning of the optical male fiber end-face exposed after
removing the UCI adapter, Tektronix recommends the following method and tools.
he optical connectors
ressed air can, such as Tektronix part
Related i
Cleanin
the Tektronix Optical Connector Cleaner part
number 020-2494-XX) are available from several
supplie
nformation
g kits for optical connectors (such as
rs.
Clean UCI
pter
ada
3. Clean contaminates from the inside wall of the hollow
ale-to-female ferrule alignment tube inside the UCI
fem
adapter.
Use the compressed air can to clean the female
input of the UCI adapter end-to-end.
Pull the pipe cleaner through the UCI adapter.
UTION.
CA
input of the UCI adapter when it is installed on the module.
Do not blow compressed air into the female
80C14 Optical Sampling Module User Manual 17
Operating Basics
Overview To clean the optical connectors Related information
Clean fiber
input
4. Advance the fiber cleaning cassette or tape-dispenser
cleaner to expose an unused clean section of the
lint-free, dr
5. Lightly drag the clean, dry, surface of the cleaning tool
cloth against the male end-face of the fiber input for a
short distan
6. Place the UCI adapter back on the cleaned fiber
end-face.
y, cleaning surface.
ce (a centimeter or two).
Dust cap
Clean
attaching
devices
7. When the module does not have a fiber attached to its
input(s),
contaminates from lodging in the female optical input.
8. Clean a
you attach to the UCI input.
attach the black dust-cap to prevent airborne
ny male fiber end-face input fiber or device that
milar cleaning method to clean the fiber
Use a si
end-face input fiber or device.
18 80C14 Optical Sampling Module User Manual
Reference
This section describes available filter selections, how to enable clock recovery,
and explains optical bandwidth.
Wavelength, Filter, and B andwidth Selection
See Table 1 for available wavelength, filter, and bandwidth information. (See
Table 1 on p
To select the optical wavelength, use the Vertical Setups menu. (See Figure 4
on page 11.)
First select the channel in the Waveform section of the menu. Then select the
Wave len g
Use the Signal Conditioning boxes to select the filter and bandwidth appropriate
for your
For more information, consult the Online Help foryourmaininstrument.
Clock Recovery
age 2.)
th that matches your system from the Setup Wavelength drop down box.
optical standard.
Optical Bandwidth
The 80C14 module comes standard with a buffered electrical signal output that,
routed to a CR175A or CR286A Clock Recovery instrument, provides
when
a recovered clock signal. Refer to the CR175A or CR286A instrument user
documentation for triggering information.
Traditionally bandwidth is defined as the frequency at which the power out is
one half the power out at a frequency near DC. In the voltage domain the power
dissipated into a resistive load (such as a 50 Ω termination of a sampler) is the
2
V
/R where V
RMS
nd R is the resistance value. The frequency dependent response of a system is
a
typically described using a logarithmic decibel scale. A value expressed in terms
of a decibel relative to a reference is defined as:
For electrical bandwidths the reference of a system is commonly the response of
stem to a sinusoidal frequency at or near DC. The point at which the system
the sy
response (power is the common parameter that is referred to in many systems) is
one half would therefore be:
is the RMS of the voltage swing seen at the resistive load,
RMS
80C14 Optical Sampling Module User Manual 19
Reference
In terms of frequency, voltage, and resistance the bandwidth is expressed as:
where V(f) is the RMS of the voltage swing response at the bandwidth frequency
and V(DC) is the RMS voltage swing response at a frequency approaching DC.
Further math yields V(f) = 0.
The expression is simplified by canceling the R and moving the squared term
inside the log expression
For the Tektronix 8000 series sampling oscilloscopes, the vertical units displayed
for an optical module are not in volts, but in watts, which are units of power.
The optical-to-electrical converter inside the module outputs a voltage whose
amplitude is linearly dependen
the voltage applied at the electrical sampler already represents optical power in
its linear form (as opposed to having to square the voltage and divide by R). For
the optical sampling modules then, the bandwidth where the displayed optical
power is one half that approaching DC is:
707 V(DC).
to a multiple outside the log expression:
t on the incoming optical power; in this condition
The V(f) is the frequency at which the vertical swing is one half (0.5) the V(DC)
not 0.707. The optical bandwidth therefore corresponds to the traditional electrical
bandwidth of -6 dB. During testing of optical modules by impulse testing, the
resulting impulse waveform is converted to frequency by Fourier transform and
the bandwidth is defined as –3 dB = 10 log(vertical swing at frequency / vertical
swing at DC). During reference r
is changed to match the industry standard definition which assumes electrical
bandwidths are –3 dB = 20 log (vertical swing at frequency / vertical swing at DC).
eceiver curve calculation, however, the definition
20 80C14 Optical Sampling Module User Manual
Reference
Bandwidth for Unfiltered
Frequency Settings
Bandwidth for Reference
Receiver Settings
The curve calcu
(2 GHz, 2.5 GHz, 12.5 GHz, 20 GHz, 30 GHz, 40 GHz, 50 GHz, 65 GHz, and
80 GHz) uses the definition for dB and bandwidth where
–3 dB = 10 log(vertical swing at frequency / vertical swing at DC); that is, the
optical bandwidth.
The curve calculation of frequency response for reference receiver settings (FC,
GbE, and OC/STM standards) uses the definition of dB and bandwidth that
matches the industry standard which assumes electrical bandwidths where –3 dB
= 20 log(vertical swing at frequency / vertical swing at DC).
lation of frequency response for the unfiltered frequency settings
80C14 Optical Sampling Module User Manual 21
Reference
22 80C14 Optical Sampling Module User Manual
Glossary
Accuracy
The closeness of the indicated value to the true value.
Analog-to-Digital Converter
A device that converts an analog signal to a digital signal.
Attenuation
A decrease in magnitude (for optical systems this is u sually optical power)
of a signal.
Autoset
A means of letting the instrument set itself to provide a stable and meaningful
display of a given waveform.
Average Optical Power (AOP)
The time averaged m easurement of the optical power over a much longer time
period than the bit rate of the s ignal.
Bandwidth
The difference between the limiting frequencies of a continuous frequency
spectrum. Bandwidth is the frequency at which the power out is one half
the power out at a frequency near DC. The range of frequencies handled by
adeviceorsystem. Bandwidthisameasure of network capacity. Analog
bandwidth is measured in cycles per second. Digital bandwidth is measured
in bits of information per second. (See page 19, Optical Bandwidth.)
Channel
A place to connect a signal or attach a network or transmission line to
sampling heads. Also, the smallest component of a math expression. A
transmission path between two or more stations.
Channel Number
The number assigned to a specific signal input connector. The top channel of
the left-most sampling head compartment of the main instrument is always
channel 1, regardless of any repositioning or omission of sampling heads.
Clock
A signal that provides a timing reference.
80C14 Optical Sampling Module User Manual 23
Glossary
Common Mode
A circumstance where a signal is induced in phase on both sides of a
differential
network.
dB
Decibel: a method of expressing power or voltage ratios. The decibel scale is
logarithmic. It is often used to express the efficiency of power distribution
systems when the ratio consists of the energy put into the system divided by
the energy delivered (or in some cases, lost) by the system. One milliwatt of
optical po
wer is usually the optical reference for 0 dBm. The formula for
decibels is:
where Viis the voltage of the incident pulse, Vlis the voltage reflected back
by the load, P
is the power out, and Piis the power in. (See page 19, Optical
o
Bandwidth.)
dBm
A logarithmi
c measure of power referenced to 1 milliwatt (1 mW optical
power = 0.0 dBm).
Degradation
A deterioration in a signal or system.
Differen
tial Mode
A method of signal transmission where the true signal and its logical
complim
ent are transmitted over a pair of conductors.
Digital signal
A signal made up of a series of on and off pulses.
Digital transmission system
A transmission system where information is transmitted in a series of on
and off pulses.
24 80C14 Optical Sampling Module User Manual
Glossary
Extinction Rat
io
The ratio of two optical power levels of a digital s ignal generated by an
e. P
optical sourc
high, and P
is the optical power level generated when the light source is
1
is the power level generated when the light source is low.
2
FEC: Forward Error Correction
Additional bits and/or coding added to a data stream to allow for automatic
error detection and correction at the receiving end. These extra bits and/or
coding tend to increase a serial data rate above the original nonFEC data
stream to accommodate the extra information added by the FEC.
Fiber Optics
A method of transmitting information in which light is modulated and
transmitted over high-purity, filaments of glass. The bandwidth of fiber optic
cable is much greate r than that of copper wire.
Impedance
The opposition to an AC signal in the wire. Impedance is very much like
resistance to a DC signal in a DC circuit. Impedance is made up of resistance,
inductive, and capacitive reactance.
Initialize
Setting the instrument main instrument to a completely known, default
condition.
Internal Clock
An internally generated trigger source that is synchronized with the Internal
Clock Output signal.
Mode
A stable condition of oscillation in a laser. A laser can operate in one mode
(single mode) or in many modes (multimode).
Modulation
A process whereby a signal is transformed from its original form into a
signal that is more suitable for transmission over the medium bet
ween the
transmitter and the receiver.
80C14 Optical Sampling Module User Manual 25
Glossary
Multimode Cabl
A thick cored optical fiber (compared to single mode cable) that can propagate
light of multi
OMA (Optical Modulation Amplitude)
The difference between the average power levels of the logic 1 level, High,
and the logic 0 level, Low, of the optical pulse signal. The levels are the
Means of the logical levels sampled within an Aperture of the logical 1 and
0 regions of the pulse. The logical 1 and 0 time intervals are marked by
the crossi
(AOP)ofthesignal.
Protocol
Formal conventions that govern the format and control of signals in a
communication process.
Recovered Clock
k signal derived from and synchronous with a received data sequence.
Acloc
Setting
The state of the front panel and system at a given time.
e
ple modes.
ngs of a reference level determined as the Average Optical Power
Single-Mode Cable
An optical cable with a very small core diameter (usually in the range of
2-10 microns). Such cables are normally used only with laser sources due to
eir very small acceptance cone. Since the cone diameter approaches the
th
wavelength of the source, only a single mode is propagated.
Trigger
An electrical event that initiates acquisition of a waveform as specified by
the time base.
Waveform
The visible representation of an input signal or combination of signals.
26 80C14 Optical Sampling Module User Manual
Index
A
Accessories, 3
list, 3
optional, 3
standard, 3
Accuracy, 23
optimizing, 12
Adjustments, 12
Analog-t
AOP
Attenuating optical signals, 8
Attenuation, 23
Autoset, 23
o-Digital converter, 23
average optical power, 23
B
Bandw
idth, 23
optical, description, 19
selection, 19
C
Channel, 23
number, 23
selection, 9
aning
Cle
module, 16
optical connectors, 16
Clock, 23
recovery, 19
recovery outputs, 10
Common mode, 24
Compensation
dark-level, 14
vertical, 12
wavelength gain, 14
Connecting optical signals, 7
D
Dark-level compensation
how to perform, 14
dB, 24
dBm, 24
Decibel, 24
Degradation, 24
Differential mode, 24
Digital signal, 24
Digital tra
nsmission system, 24
E
Electrostatic discharge, 4
Extinction ratio, 25
F
Features, 1
FEC, 25
Fiber optics, 25
selection, 19
Filter
Forward Error Correction, 25
Front panel controls, 9
G
Getting started, 1
H
Hold down screws, 10
I
Impedance, 25
itialize, 25
In
Input connector, 9
Installation, 4
Internal clock, 25
M
Main instrument commands, 10
Manuals
part numbers, 3
Measurement accuracy
optimizing, 12
Mode, 25
Modulation, 25
Module features, 1
Multimode cable, 26
O
OMA
optical modulation
amplitude, 26
Operating basics, 7
Optical
dark-leve
input connector, 9
vertical compensation, 12
wavelength gain
Optimizing measurement
accurac
Optional accessories list, 3
Options
list, 3
Outputs
clock, 10
data
l compensation, 14
compensation, 14
y, 12
,10
P
Procedure
perform dark-level
compensation, 14
perform user wavelength gain
compensation, 14
erform vertical
p
compensation, 12
Product description, 1
Programmer interface, 12
Protocol, 26
R
Recovered
clock, 26
Reference, 19
S
Safety Summary, iv
Sampling head features, 1
SELECT CHANNEL button, 9
Setting, 26
80C14 Optical Sampling Module User Manual 27
Index
Single-mode ca
Specifications, vii
Standard accessories, 3
System interaction, 8
ble, 26
T
Trigger, 26
U
Usage, 7
User adjustmen
User wavelength compensation
how to perform, 14
ts, 12
V
Vertical compensation
how to perform, 12
W
Waveform, 26
Wavelength
selection, 19
Wavelength gain
compensation, 14
28 80C14 Optical Sampling Module User Manual
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