Anritsu MS2681A User manual

i
17th Edition
For safety and warning information, please read this
manual before attempting to use the equipment.
Keep this manual with the equipment.
MS2681A/MS2683A/MS2687A/MS2687B
Spectrum Analyzer
Operation Manual
Vol. 1
(Basic Operating Instructions)
Document No.: M-W1754AE-17.0
ANRITSU CORPORATION

ii
To prevent the risk of personal injury or loss related to equipment malfunction, Anritsu Corporation uses the following
safety symbols to indicate safety-related information. Insure that you clearly understand the meanings of the symbols
BEFORE using the equipment. Some or all of the following five symbols may not be used on all Anritsu equipment.
In addition, there may be other labels attached to products which are not shown in the diagrams in this manual.
Symbols used in manual
DANGER
WARNING
CAUTION
Safety Symbols Used on Equipment and in Manual
The following safety symbols are used inside or on the equipment near operation locations to provide information
about safety items and operation precautions. Insure that you clearly understand the meanings of the symbols
and take the necessary precautions BEFORE using the equipment.
This indicates a prohibited operation. The prohibited operation is indicated
symbolically in or near the barred circle.
This indicates an obligatory safety precaution. The obligatory operation is indi-
cated symbolically in or near the circle.
This indicates warning or caution. The contents are indicated symbolically in or
near the triangle.
This indicates a note. The contents are described in the box.
These indicate that the marked part should be recycled.
MS2681A/MS2683A/MS2687A/MS2687B
Spectrum Analyzer
Operation Manual Vol. 1 (Basic Operating Instructions)
20 April 2000 (First Edition)
25 August 2006 (17th Edition)
Copyright © 2000-2006, ANRITSU CORPORATION.
All rights reserved. No part of this manual may be reproduced without the prior written permission of the
publisher.
The contents of this manual may be changed without prior notice.
Printed in Japan
This indicates a very dangerous procedure that could result in serious injury or
death if not performed properly.
This indicates a hazardous procedure that could result in serious injury or death if
not performed properly.
This indicates a hazardous procedure or danger that could result in light-to-severe
injury, or loss related to equipment malfunction, if proper precautions are not taken.
Safety Symbols

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For Safety
WARNING
1. ALWAYS refer to the operation manual when working near locations at
which the alert mark shown on the left is attached. If the operation, etc.,
is performed without heeding the advice in the operation manual, there
is a risk of personal injury. In addition, the equipment performance may
be reduced.
Moreover, this alert mark is sometimes used with other marks and de-
scriptions indicating other dangers.
2. Measurement Categories
This instrument is designed for Measurement category I (CAT I). Don't
use this instrument at the locations of measurement categories from
CAT II to CAT IV.
In order to secure the safety of the user making measurements, IEC
61010 clarifies the range of use of instruments by classifying the loca-
tion of measurement into measurement categories from I to IV.
The category outline is as follows:
Measurement category I (CAT I):
Secondary circuits of a device connected to an outlet via a power trans-
former etc.
Measurement category II (CAT II):
Primary circuits of a device with a power cord (portable tools, home
appliance etc.) connected to an outlet.
Measurement category III (CAT III):
Primary circuits of a device (fixed equipment) to which power is directly
supplied from the power distribution panel, and circuits from the distri-
bution panel to outlets.
Measurement category IV (CAT IV):
All building service-line entrance circuits through the integrating watt-
meter and primary circuit breaker (power distribution panel).
3. When supplying power to this equipment, connect the accessory 3-pin
power cord to a grounded outlet. If a grounded outlet is not available,
before supplying power to the equipment, use a conversion adapter and
ground the green wire, or connect the frame ground on the rear panel of
the equipment to ground. If power is supplied without grounding the
equipment, there is a risk of receiving a severe or fatal electric shock.
or

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For Safety
WARNING
4. This equipment cannot be repaired by the operator. DO NOT attempt to
remove the equipment covers or unit covers or to disassemble internal
components. Only qualified service technicians with a knowledge of
electrical fire and shock hazards should service this equipment. There
are high-voltage parts in this equipment presenting a risk of severe in-
jury or fatal electric shock to untrained personnel. In addition, there is a
risk of damage to precision components.
5. The performance-guarantee seal verifies the integrity of the equipment.
To ensure the continued integrity of the equipment, only Anritsu service
personnel, or service personnel of an Anritsu sales representative,
should break this seal to repair or calibrate the equipment. If the perfor-
mance-guarantee seal is broken by you or a third party, the perfor-
mance of the equipment cannot be guaranteed.
6. This equipment should be used in the correct position. If the cabinet is
turned on its side, etc., it will be unstable and may be damaged if it falls
over as a result of receiving a slight mechanical shock.
And also DO NOT use this equipment in the position where the power
switch operation is difficult.
7. DO NOT short the battery terminals and never attempt to disassemble it
or dispose of it in a fire. If the battery is damaged by any of these
actions, the battery fluid may leak.
This fluid is poisonous.
DO NOT touch it, ingest it, or get in your eyes. If it is accidentally in-
gested, spit it out immediately, rinse your mouth with water and seek
medical help. If it enters your eyes accidentally, do not rub your eyes,
irrigate them with clean running water and seek medical help. If the
liquid gets on your skin or clothes, wash it off carefully and thoroughly.
8. This instrument uses a Liquid Crystal Display (LCD); DO NOT subject
the instrument to excessive force or drop it. If the LCD is subjected to
strong mechanical shock, it may break and liquid may leak.
This liquid is very caustic and poisonous.
DO NOT touch it, ingest it, or get in your eyes. If it is ingested acciden-
tally, spit it out immediately, rinse your mouth with water and seek medi-
cal help. If it enters your eyes accidentally, do not rub your eyes, irrigate
them with clean running water and seek medical help. If the liquid gets
on your skin or clothes, wash it off carefully and thoroughly.
Repair
WARNING
Calibration
Falling Over
Battery Fluid
LCD

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For Safety
CAUTION
1. Before Replacing the fuses, ALWAYS remove the power cord from the
poweroutlet and replace the blown fuses. ALWAYS use new fuses of
the type and rating specified on the fuse marking on the rear panel of
the cabinet.
T6.3A indicates a time-lag fuse.
2. Keep the power supply and cooling fan free of dust.
• Clean the power inlet regularly. If dust accumulates around the
power pins, there is a risk of fire.
• Keep the cooling fan clean so that the ventilation holes are not ob-
structed. If the ventilation is obstructed, the cabinet may overheat
and catch fire.
3. Maximum DC voltage ratings:
RF Input ±DC 0 V
Maximum AC power (continuous wave) ratings:
RF Input +30 dBm (RF ATT ≥10 dB)
NEVER input a over maximum ratings to RF Input, excessive power
may damage the internal circuits.
◆MS2681A/MS2683A (plus opt.08 pre-amplifier ON)
Maximum AC power (continuous wave) ratings:
RF Input +10 dBm (RF ATT ≥10 dB)
NEVER input a over maximum ratings to RF Input, excessive power
may damage the internal circuits.
Replacing Fuse
CAUTION
Cleaning
Check Terminal

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For Safety
CAUTION
The power for memory backup is supplied by a Poly-carbonmonofluoride
Lithium Battery. This battery should only be replaced by a battery of the
same type; since replacement can only be made by Anritsu, contact the
nearest Anritsu representative when replacement is required.
Note: The battery used in this equipment has a maximum useful life of
7 years. It should be replaced before this period has elapsed.
This equipment stores data and programs using Plug-in Memory card.
Data and programs may be lost due to improper use or failure.
ANRITSU therefore recommends that you backup the memory.
Anritsu Corporation will not accept liability for lost data.
Pay careful attention to the following points.
•Do not remove the memory card from equipment being accessed.
•Isolate the card from static electricity.
•The PC-ATA card or Compact Flash card operation is not guaranteed
generally.
This equipment uses chemical compound semiconductor including ars-
enide.
At the end of its life, the equipment should be recycled or disposed properly
according to the local disposal regulations.
Replacing Memory
Back-up Battery
External
Storage Media
Disposing of The
Product

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Equipment Certificate
Anritsu Corporation certifies that this equipment was tested before shipment using calibrated
measuring instruments with direct traceability to public testing organizations recognized by
national research laboratories including the National Institute of Advanced Industrial Science
and Technology, and the National Institute of Information and Communications Technology,
and was found to meet the published specifications.
Anritsu Warranty
Anritsu Corporation will repair this equipment free-of-charge if a malfunction occurs
within one year after shipment due to a manufacturing fault, under the condition that
this warranty is void when:
• The fault is outside the scope of the warranty conditions described in the operation
manual.
• The fault is due to mishandling, misuse, or unauthorized modification or repair of
the equipment by the customer.
• The fault is due to severe usage clearly exceeding normal usage.
• The fault is due to improper or insufficient maintenance by the customer.
• The fault is due to natural disaster including fire, flooding, earthquake, etc.
• The fault is due to use of non-specified peripheral equipment, peripheral parts,
consumables, etc.
• The fault is due to use of a non-specified power supply or in a non-specified instal-
lation location.
In addition, this warranty is valid only for the original equipment purchaser. It is not
transferable if the equipment is resold.
Anritsu Corporation will not accept liability for equipment faults due to unforeseen and
unusual circumstances, nor for faults due to mishandling by the customer.
Anritsu Corporation Contact
In the event that this equipment malfunctions, contact an Anritsu Service and Sales
office. Contact information can be found on the last page of the printed version of this
manual, and is available in a separate file on the CD version.

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Notes On Export Management
This product and its manuals may require an Export License/Approval by
the Government of the product's country of origin for re-export from your
country.
Before re-exporting the product or manuals, please contact us to confirm
whether they are export-controlled items or not.
When you dispose of export-controlled items, the products/manuals are
needed to be broken/shredded so as not to be unlawfully used for
military purpose.

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Crossed-out Wheeled Bin Symbol
Equipment marked with the Crossed-out Wheeled Bin Symbol complies with council
directive 2002/96/EC (the "WEEE Directive") in European Union.
For Products placed on the EU market after August 13, 2005, please contact your local
Anritsu representative at the end of the product's useful life to arrange disposal in ac-
cordance with your initial contract and the local law.

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Front Panel Power Switch
To prevent malfunction caused by accidental touching, the front power switch of this equipment turns on the
power if it is pressed continuously for about one second in the standby state. If the switch is pressed continu-
ously for one second in the power-on state, the equipment enters the standby state.
In the power-on state, if the power plug is removed from the outlet, then reinserted into it, the power will not
be turned on. Also, if the lines is disconnected due to momentary power supply interruption or power failure,
the power will not be turned on (enters the standby state) even if the line is recovered.
This is because this equipment enters the standby state and prevents incorrect data from being acquired when
the line has to be disconnected and reconnected.
For example, if the sweep time is 1,000 seconds and data acquisition requires a long time, momentary power
supply interruption (power failure) might occur during measurement and the line could be recovered auto-
matically to power-on. In such a case, the equipment may mistake incorrect data for correct data without
recognizing the momentary power supply interruption.
If this equipment enters the standby state due to momentary power supply interruption or power failure,
check the state of the measuring system and press the front power switch to restore power to this equipment.
Further, if this equipment is built into a system and the system power has to be disconnected then recon-
nected, the power for this equipment must also be restored by pressing the front power switch.
Consequently, if this equipment is built into remote monitoring systems that use MODEMs, please install
option 46 “Auto Power Recovery”to equipment.

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ABOUT DETECTION MODE
This instrument is a spectrum analyzer which uses a digital storage system. The spectrum analyzer makes
level measurements in frequency steps obtained by dividing the frequency span by the number of measure-
ment data points (501). This method of measurement cannot detect the signal peak level if the spectrum of
a received signal is narrower than these frequency steps.
To resolve this problem, this instrument usually operates in positive peak detection mode and normal detec-
tion mode. In the positive peak detection mode, the highest level within the frequency range between the
sample points can be held and traced. In the normal detection mode, both the positive peak and the negative
peak can be traced.
Positive peak detection mode should be used for almost all measurements including normal signal level
measurement, pulsed noise analysis, and others. It is impossible to measure the signal level accurately in
sample detection mode or in negative peak detection mode.
Use of sample detection mode is restricted to random noise measurement, occupied frequency bandwidth
measurement for analog communication systems, and adjacent-channel leakage power measurement, etc.
Measurement Item
•Normal signal ......................................................................................... POS PEAK
•Random noise ......................................................................................... SAMPLE
•Pulsed noise ......................................................................................... NORMAL (POSI-NEG)
•Occupied frequency bandwidth, adjacent-channel leakage power .............. SAMPLE
(for analog communication systems)
•Occupied frequency bandwidth, adjacent-channel leakage power .............. POS PEAK or SAMPLE
(for digital communication systems)
When a detection mode is specified as one of the measurement methods, make the measurement in the
specified detection mode.

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CE Conformity marking
Anritsu affixes the CE Conformity marking on the following product(s) in accordance
with the Council Directive 93/68/EEC to indicate that they conform with the EMC and
LVD directive of the European Union (EU).
CE Marking
1. Product Model
Model: MS2681A/MS2683A/MS2687A/MS2687B
Spectrum Analyzer
and
Software: MX268701B W-CDMA Measurement software
MX268702A GSM Measurement software
MX268703A CDMA Measurement software
MX268704A 1xEV-DO Measurement software
MX268705A Pi/4DQPSK Measurement software
MX268706A ADVANCED PHS Measurement software
MX268730A WLAN Measurement software
MX268732A WLAN Measurement software Limited version
and
Accessories: MA4601A Power Sensor
MA4701A Power Sensor
MA4703A Power Sensor
MA4705A Power Sensor
2. Applied Directive
EMC: Council Directive 89/336/EEC
LVD: Council Directive 73/23/EEC

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3. Applied Standards
• EMC: Emission: EN 61326: 1997 + A1: 1998 + A2: 2001 + A3: 2003
(Class A)
Immunity: EN 61326: 1997 + A1: 1998 + A2: 2001 + A3: 2003
(Annex A)
Performance Criteria*
IEC 61000-4-2 (ESD) B
IEC 61000-4-3 (EMF) A
IEC 61000-4-4 (Burst) B
IEC 61000-4-5 (Surge) B
IEC 61000-4-6 (CRF) A
IEC 61000-4-8 (RPFMF) A
IEC 61000-4-11 (V dip/short) B
*: Performance Criteria
A: During testing normal performance within the specification lim-
its
B: During testing, temporary degradation, or loss of function or per-
formance which is self-recovering
Harmonic current emissions:
EN 61000-3-2: 2000 (Class A equipment)
• LVD: EN 61010-1: 2001 (Pollution Degree 2)

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C-tick Conformity marking
Anritsu affixes the C-tick marking on the following product(s) in accordance with the
regulation to indicate that they conform with the EMC framework of Australia/New
Zealand.
C-tick marking
N274
1. Product Model
Model: MS2681A/MS2683A/MS2687A/MS2687B
Spectrum Analyzer
and
Software: MX268701B W-CDMA Measurement software
MX268702A GSM Measurement software
MX268703A CDMA Measurement software
MX268704A 1xEV-DO Measurement software
MX268705A Pi/4DQPSK Measurement software
MX268706A ADVANCED PHS Measurement software
MX268730A WLAN Measurement software
MX268732A WLAN Measurement software Limited version
and
Accessories: MA4601A Power Sensor
MA4701A Power Sensor
MA4703A Power Sensor
MA4705A Power Sensor
2. Applied Standards
EMC: Emission: EN 61326: 1997 + A1: 1998 + A2: 2001 + A3: 2003
(ISM, Group 1, Class A equipment)

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Power Line Fuse Protection
For safety, Anritsu products have either one or two fuses in the AC power lines as
requested by the customer when ordering.
Single fuse: A fuse is inserted in one of the AC power lines.
Double fuse: A fuse is inserted in each of the AC power lines.

xvi

I
About This Manual
(1) Composition of MS2681A/MS2683A/MS2687A/MS2687B Spectrum
Analyzer Operation Manuals
The MS2681A/MS2683A/MS2687A/MS2687B Spectrum Analyzer operation manu-
als of the standard type are composed of the following three documents. Use them
properly according to the usage purpose.
Vol. 1
Vol. 2
Vol. 3
Composition
of
Operation Manuals
(Remote control part)
Detailed operating instruction part
Basic operating instruction part
Programming part
Basic operating instruction part:
Provides information on the MS2681A/MS2683A/MS2687A/
MS2687B outline, preparation before use, panel description,
basic operation, soft-key menu and performance tests.
Detailed operating instruction part:
Provides information on the detailed panel operating instruc-
tions on MS2681A/MS2683A/MS2687A/MS2687B that ex-
pand on the basic operation and soft-key menu in the Basic Op-
erating Instruction Part.
Programming part (Remote control part):
Provides information on RS-232C remote control, GPIB re-
mote control and sample programs.

II
Table of Contents
For Safety ...................................................... iii
About This Manual........................................ I
Section 1 General......................................... 1-1
Product Outline ....................................................................... 1-3
Composition of Operation Manual .......................................... 1-4
Equipment Configuration ........................................................ 1-5
Optional Accessories and Peripherals .................................... 1-7
Specifications .......................................................................... 1-8
Section 2 Preparations Before Use ............ 2-1
Installation Site and Environmental Conditions ....................... 2-3
Safety Measures ..................................................................... 2-4
Installation ............................................................................... 2-6
Preparations before Power-on ................................................ 2-7
Precaution for Handling Memory Card .................................... 2-11
Section 3 Panel Description........................ 3-1
Table of Front and Rear Panel Features ................................ 3-3
Section 4 Soft-Key Menu ............................. 4-1
Soft-key Menu List .................................................................. 4-4
Spectrum mode Menu Tree .................................................... 4-6
Config mode Menu Tree ......................................................... 4-30

III
Section 5 Basic Operation Procedure........ 5-1
Signal Display ......................................................................... 5-3
Marker Operation .................................................................... 5-6
“Measure” Function Check ...................................................... 5-8
Shifting of result position ......................................................... 5-9
Screen Hard Copy .................................................................. 5-10
Section 6 Performance Test........................ 6-1
Requirement for Performance Test ......................................... 6-3
Instruments Required for Performance Test ........................... 6-4
Performance Test ................................................................... 6-6
Service .................................................................................... 6-56
Section 7 Storage and Transportation ....... 7-1
Cleaning Cabinet .................................................................... 7-3
Storage Precautions ............................................................... 7-4
Repacking and Transportation ................................................ 7-5
Appendix A Front and Rear Panel Layout ... A-1
Appendix B Block Diagram ......................... B-1
Appendix C Performance Test Record ...... C-1

IV.