Tektronix P6701B User manual

Service Manual
P6701B, P6703B & P6723
O/E Converters
070-9892-03
*P070989203*
070989203
Warning
The servicing instructions are for use by qualified
personnel only. To avoid personal injury, do not
perform any servicing unless you are qualified to
do so. Refer to all safety summaries prior to
performing service.

Copyright ©Tektronix, Inc. All rights reserved.
Tektronix products are covered by U.S. and foreign patents, issued and pending. Information in this publication supercedes
that in all previously published material. Specifications and price change privileges reserved.
Tektronix, Inc., P.O. Box 500, Beaverton, OR 97077
TEKTRONIX and TEK are registered trademarks of Tektronix, Inc.

WARRANTY
Tektronix warrants that the products that it manufactures and sells will be free from defects in materials and
workmanship for a period of one (1) year from the date of shipment. If a 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.
In order to obtain service under this warranty, Customer must notify Tektronix of the defect before the expiration
of 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
resulting from attempts by personnel other than Tektronix representatives to install, repair or service the product;
b) to repair damage resulting from improper use or connection to 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 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. TEKTRONIX’
RESPONSIBILITY TO REPAIR OR REPLACE DEFECTIVE PRODUCTS IS THE SOLE 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.

Service Assurance
If you have not already purchased Service Assurance for this product, you may do so at any time during the
product’s warranty period. Service Assurance provides Repair Protection and Calibration Services to meet your
needs.
Repair Protection extends priority repair services beyond the product’s warranty period; you may purchase up to
three years of Repair Protection.
Calibration Services provide annual calibration of your product, standards compliance and required audit
documentation, recall assurance, and reminder notification of scheduled calibration. Coverage begins upon
registration; you may purchase up to five years of Calibration Services.
Service Assurance Advantages
HPriced well below the cost of a single repair or calibration
HAvoid delays for service by eliminating the need for separate purchase authorizations from your company
HEliminates unexpected service expenses
For Information and Ordering
For more information or to order Service Assurance, contact your Tektronix representative and provide the
information below. Service Assurance may not be available in locations outside the United States of America.
Name VISA or Master Card number and expiration
Company date or purchase order number
Address Repair Protection (1,2, or 3 years)
City, State, Postal code Calibration Services (1,2,3,4, or 5 years)
Country Instrument model and serial number
Phone Instrument purchase date

P6701B, P6703B, and P6723 Service Manual i
Table of Contents
General Safety Summary iii...................................
Preface v...................................................
Related Manuals v.................................................
Contacting Tektronix v.............................................
P6701B and P6703B Specifications 1...........................
Warranted Characteristics 1..........................................
Typical Characteristics 2............................................
Nominal Characteristics 4...........................................
P6723 Specifications 5.......................................
Warranted Characteristics 5..........................................
Typical Characteristics 6............................................
Nominal Characteristics 6...........................................
P6701B and P6703B Performance Verification 7.................
Equipment Required 7..............................................
Noise Equivalent Power 8...........................................
Output Zero 9.....................................................
DC Conversion Gain 9.............................................
AC Conversion Gain 10.............................................
P6723 Performance Verification 13..............................
Equipment Required 13..............................................
Output Amplitude 14................................................
Maintenance 17..............................................
Cleaning the Optical Connectors 17....................................
Cleaning the External Parts 18........................................
Handling 18.......................................................
Replacing TekProbe Interface Pins 19..................................
Removing and Replacing the TekProbe Interface Collar 20.................
Options 21..................................................
Replaceable Parts 23..........................................

Table of Contents
ii P6701B, P6703B, and P6723 Service Manual

P6701B, P6703B, and P6723 Service Manual iii
General Safety Summary
Review the following safety precautions to avoid injury and prevent damage to
this product or any products connected to it. To avoid potential hazards, use this
product only as specified.
Only qualified personnel should perform service procedures.
Observe All Terminal Ratings. To avoid fire or shock hazard, observe all ratings
and markings on the product. Consult the product manual for further ratings
information before making connections to the product.
Do Not Operate Without Covers. Do not operate this product with covers or panels
removed.
Wear Eye Protection. Wear eye protection if exposure to high-intensity rays or
laser radiation exists.
Do Not Operate With Suspected Failures. If you suspect there is damage to this
product, have it inspected by qualified service personnel.
Do Not Operate in Wet/Damp Conditions.
Do Not Operate in an Explosive Atmosphere.
Keep Product Surfaces Clean and Dry.
Terms in this Manual. These terms may appear in this manual:
WARNING. 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.
Terms on the Product. These terms may appear on the product:
DANGER indicates an injury hazard immediately accessible as you read the
marking.
WARNING indicates an injury hazard not immediately accessible as you read the
marking.
CAUTION indicates a hazard to property including the product.
ToAvoidFireor
Personal Injury
Symbols and Terms

General Safety Summary
iv P6701B, P6703B, and P6723 Service Manual
Symbols on the Product. The following symbols may appear on the product:
Protective Ground
(Earth) Terminal
CAUTION
Refer to Manual
Double
Insulated
WARNING
High Voltage

P6701B, P6703B, and P6723 Service Manual v
Preface
This manual contains specifications and procedures for servicing the P6701B,
P6703B, and P6723 O/E Converters.
Related Manuals
For operating instructions, refer to the P6701B, P6703B, and P6723 Instruc-
tions (070-9890-XX).
Contacting Tektronix
Phone [phone]*
Address Tektronix, Inc.
Department or name (if known)
14200 SW Karl Braun Drive
P.O. Box 500
Beaverton, OR 97077
USA
Web site www.tektronix.com
Sales support 1-800-833-9200, select option 1*
Service support 1-800-833-9200, select option 2*
Technical support Email: [e-mail]
1-800-833-9200, select option 3*
6:00 a.m. -- 5:00 p.m. Pacific time
*This phone number is toll free in North America. After office hours, please leave a
voice mail message.
Outside North America, contact a Tektronix sales office or distributor; see the
Tektronix web site for a list of offices.

Preface
vi P6701B, P6703B, and P6723 Service Manual

P6701B, P6703B, and P6723 Service Manual 1
P6701B and P6703B Specifications
The specifications in Tables 1 through 3 apply to a P6701B or P6703B O/E
converter. The converter must have a warm-up period of at least 20 minutes and
be in an environment that does not exceed the limits described in Table 1.
Specifications for the P6701B and P6703B O/E converters fall into three
categories: warranted, typical, and nominal characteristics.
Warranted Characteristics
Warranted characteristics (Table 1) describes guaranteed performance within
tolerance limits or certain type-tested requirements. Warranted characteristics
that have checks in the Performance Verification section of the service manual
(070-9892-XX) are marked with the nsymbol.
Table 1: P6701B and P6703B warranted electrical characteristics
DC optical input dynamic range DC electrical out will meet conversion gain specifications up to
11 mW (0 dBm) peak optical power input
Absolute maximum non-destructive optical input 10 mW average power; 20 mW peak power
nDC conversion gain P6701B: 1 V/mW ±8% at DC, 780 nm
P6703B: 1 V/mW ±8% at DC, 1310 nm
nAC conversion gain P6701B: 1 V/mW ±8%, with ≤100 WP-P optical modulation,
780 nm
P6703B: 1 V/mW ±8%, with ≤100 WP-P optical modulation,
1310 nm
nOutput zero ≤±1mVinto50Ω,20to25_C
nNoise equivalent power
(with 1 GHz low-pass filter)
P6701B: ≤0.87 WRMS
P6703B: ≤0.59 WRMS
(≤28 pWHz
)
(≤19 pWHz
)
Output impedance 50 Ω±10%
Temperature Operating: 0 to +50_C
Nonoperating: --40 to +71_C

P6701B and P6703B Specifications
2P6701B, P6703B, and P6723 Service Manual
Table 1: P6701B and P6703B warranted electrical characteristics (cont.)
Humidity Operating: 0--90% RH, tested at
+30to+50_ C
Nonoperating: 0--90% RH, tested at
+30to+60_ C
Altitude Operating: 4,572 m (15,000 ft)
Nonoperating: 15,240 m (50,000 ft)
Typical Characteristics
Typical characteristics (Table 2) describe typical but not guaranteed performance.
Table 2: P6701B and P6703B typical electrical characteristics
Effective wavelength range P6701B: 500 to 950 nm
P6703B: 1100 to 1650 nm
Wavelength dependent gain SeeFigure1
Optical bandwidth P6701B: ≥1.0 GHz
P6703B: ≥1.2 GHz
Rise time P6701B: ≤475 ps
P6703B: ≤390 ps
(peak optical signal input < 100 WP-P)
Aberrations ≤±15% peak optical signal input < 200 WP-P

P6701B and P6703B Specifications
P6701B, P6703B, and P6723 Service Manual 3
400 500 600 700 800 900 1000
0.2
0.3
0.4
0.5
0.6
0.7
0.8
0.9
1.0
1.1
1.2
Wavelength (nm)
Relative Conversion Gain
P6701B
1000 1200 1400 1600
Wavelength (nm)
P6703B
~0.8 at 850nm
~1.1 at 1550 nm
Normalized to
780nm at 1 V/mW
0.2
0.3
0.4
0.5
0.6
0.7
0.8
0.9
1.0
1.1
1.2
Relative Conversion Gain
Normalized to 1310nm at 1 V/mW
Figure 1: Typical wavelength dependent gain (25_C ambient)

P6701B and P6703B Specifications
4P6701B, P6703B, and P6723 Service Manual
Nominal Characteristics
Nominal characteristics (Table 3) describe guaranteed traits, but the traits do not
have tolerance limits.
Table 3: P6701B and P6703B nominal electrical characteristics
Optical input coupling Accepts up to 62.5 m core diameter, Numerical Aperture ≤0.29
Optical fiber dressing > 1 inch bend radius, not to exceed a bend radius of < 1 inch to
maintain performance.
Absolute non-destructive fiber bend 0.5 inch bend radius
DC conversion gain linearity < 3% deviation in DC conversion gain from 50 W to 1000 W
average optical input relative to conversion gain with 500 W
average optical power input.
Output zero drift ≤±1.5 mV with output load requirement met for ideally stable
optical input, 0--25_C
Output load requirement 50 Ω±1%

P6701B, P6703B, and P6723 Service Manual 5
P6723 Specifications
The specifications in Tables 4 through 6 apply to a P6723 O/E converter. The
converter must have a warm-up period of at least 20 minutes and be in an
environment that does not exceed the limits described in Table 4.
Specifications for the P6723 O/E converter fall into three categories: warranted,
typical, and nominal characteristics.
Warranted Characteristics
Warranted characteristics (Table 4) describes guaranteed performance within
tolerance limits or certain type-tested requirements. Warranted characteristics
that have checks in the Performance Verification section of the service manual
(070-9892-XX) are marked with the nsymbol.
Table 4: P6723 warranted electrical characteristics
Optical sensitivity -- 8.0 dBm maximum average optical power,
-- 28 dBm minimum average optical power1
Output rise time and fall time ≤455 ps
nOutput amplitude Minimum: ≥690 mVP-P
Maximum: ≤1.1 VP-P
Output impedance 50 ±10%
Output VSWR < 1.5:1 from 10 MHz to 1 GHz
< 2.0:1 from 1 GHz to 2 GHz
Temperature Operating: 0 to +50_C
Nonoperating: --40 to +71_C
Humidity Operating: 0--90% RH, tested at
+30to+50_ C
Nonoperating: 0--90% RH, tested at
+30to+60_ C
Altitude Operating: 4,572 m (15,000 ft)
Nonoperating: 15,240 m (50,000 ft)
1Measured with an optical input using 223 - 1 pseudorandom word having a 50% duty cycle.

P6723 Specifications
6P6701B, P6703B, and P6723 Service Manual
Typical Characteristics
Typical characteristics (Table 5) describe typical but not guaranteed performance.
Table 5: P6723 typical electrical characteristics
Effective wavelength range 1100 to 1570 nm
Aberrations ≤±15%, 20% P-P total
Nominal Characteristics
Nominal characteristics (Table 6) describe guaranteed traits, but the traits do not
have tolerance limits.
Table 6: P6723 nominal electrical characteristics
Optical input coupling Accepts up to 62.5 m core diameter, Numerical Aperture ≤0.29
Optical data rate 20 MB/s minimum1
650 Mb/s maximum1
Optical fiber dressing > 1.5-inch bend radius
Absolute non-destructive fiber bend 0.5-inch bend radius
Output load requirement 50 Ω±1%, AC or DC coupled
1Measured with an optical input using 223 - 1 pseudorandom word having a 50% duty cycle.

P6701B, P6703B, and P6723 Service Manual 7
P6701B and P6703B Performance Verification
Use the following procedures to verify the warranted specifications of the
P6701B and P6703B O/E converters. Before beginning these procedures, refer to
page 12 and photocopy the test record and use it to record the performance test
results. The recommended calibration interval is one year.
These procedures test the following specifications:
HNoise equivalent power
HOutput zero
HDC conversion gain
HAC conversion gain
Equipment Required
Table 7 lists the equipment required to perform the performance verification
procedure. The types and quantities of connectors may vary depending on the
specific equipment you use.
The instrument should be given a 20 minute warm up period and ambient
temperature must be between 20 and 30 degrees C.
Table 7: Test equipment
Description Minimum requirements Example product
Optical power meter with
head and adapters
Accuracy > 2.5%, resolution >
5 pW, Max power > 1 mW, cali-
brated from 700 nm -- 1600 nm
HP 8153A with power
sensor HP 81532A and
HP 81531A
P6701B only: 780 nm cal
source
output > 200uW (CW)1,
stability > 0.1 dB over 5 minutes,
modulated square wave @ 10 kHz
with off modulation at zero-light
level
P6701B only: 850 nm cal
source
output > 200uW1,
stability > 0.1 dB over 5 minutes,
modulated square wave @ 10 kHz
with off modulation at zero-light
level

P6701B and P6703B Performance Verification
8P6701B, P6703B, and P6723 Service Manual
Table 7: Test equipment (cont.)
Description Example productMinimum requirements
P6703B only: 1310 nm cal
source
output > 200uW1,
stability > 0.1 dB over 5 minutes,
modulated square wave @ 10 kHz
with off modulation at zero-light
level
P6703B only: 1550 nm cal
source
output > 200uW (CW)1,
stability > 0.1 dB over 5 minutes,
modulated square wave @ 10 kHz
with off modulation at zero-light
level
RF power meter noise<.1mV,BW>4GHz HP 437B with power sensor
HP 8481D
P6703B only: 1300 nm
impulse generator
OIG 502
P6701B only: 850 nm
impulse generator
OIG 501
Sampling oscilloscope 11K (1140X, CSA40xX, or
DSA60X)
Adjustable optical
attenuator
4 decades, 50um core fiber, FC-
style connectors
JDS 5000L with 62 m
fiber with FC connectors
Digital voltmeter 4 1/2 digit Tektronix DMM916
50 ohm termination ±1% 011-0049-01
Optical cable FC-FC multimode, 62.5um, 2
meters
174-2322-00
Inline optical adapter FC female to FC female 131-5039-00
TekProbe Power Supply Tektronix 1103
Low-pass filter 1GHz Mini Circuits SLP 1000
1CW and modulated mode available: modulation with OFF level at or below 0.1uW,
optical falltime < 1us
Noise Equivalent Power
1. Power the P670XB under test using an 1103 Tekprobe power supply.
2. Connect the P670XB output channel from the 1103 power supply to the
power meter input with the 1 GHz filter in series with this connection.
3. With the dust cover on the input to the P670XB, the power meter reading
should be ≤15 nW for the P6701B and ≤7 nW for the P6703B.

P6701B and P6703B Performance Verification
P6701B, P6703B, and P6723 Service Manual 9
Output Zero
1. Attach 1103 powered P670XB output to voltmeter with 50 ohm termination.
2. Install optical dust cover on input to P670XB under test.
3. Check that output voltage is ≤1mV.
DC Conversion Gain
NOTE. Make sure that the optical connector ends of both the fiber jumpers and
the input fiber of the O/E converter under test are well cleaned before perform-
ing this step. Use isopropyl alcohol, lint-free lense paper and clean compressed
air to clean the fiber ferrule ends. Refer to page 17 for the recommended
cleaning procedure.
1. Connect 780 nm laser to attenuator.
NOTE. The fiber bend radius of the P670XB fiber input should lay with >1-inch
bend radius along the fiber’s entire length. Although this precaution must be
maintained throughout the entire PV procedure, it is especially important for this
step in order to accurately adjust and measure DC-conversion gain of the
P670XB.
2. Connect FC connector of the optical attenuator to FC-receptacle of the
optical power meter using the optical cable. Use the appropriate optical
power meter sensing head with calibrated measurement for a wavelength
span including 780 nm and 850 nm. Be sure the optical power meter
wavelength setting is at 780 nm.
3. Adjust attenuator or the optical source source so that the power meter reads
100 W.
4. Move the FC fiber end (the one now adjusted to 100 W average power)
from the optical power meter and connect to the P670XB input under test by
using the FC-FC inline female-female optical adapter.
5. Attach voltmeter with 50 ohm termination to 1103 powered P670XB output.
6. Check for 100 mV reading on voltmeter, ±8%. (The 780 nm conversion gain
is 1.00 V/mW.)
P6701B

P6701B and P6703B Performance Verification
10 P6701B, P6703B, and P6723 Service Manual
1. Connect 1310 nm laser to attenuator.
NOTE. The longer wavelengths of 1310 nm and especially 1550 nm are more
sensitive to loss in fiber due to bending of the fiber than the short wavelength.
The fiber bend radius of the P670XB fiber input should lay with >1-inch bend
radius along the fiber’s entire length. Although this precaution must be
maintained throughout the entire PV procedure, it is especially important for this
step in order to accurately adjust and measure DC-conversion gain of the
P670XB.
2. Connect FC connector of the optical attenuator to the FC receptacle of the
optical power meter using optical cable; use the appropriate optical power
meter sensing head with calibrated measurement for a wavelength span
including 1310 nm and 1550 nm. Be sure the optical power meter wave-
length setting is at 1310 nm.
3. Adjust the attenuator or optical source so that the power meter reads 100 W.
4. Move the FC fiber end (the one now adjusted to 100 W average power)
from the optical power meter and connect to the P670XB input under test by
using the FC-FC inline female-female optical adapter.
5. Attach voltmeter with 50 ohm termination to 1103 powered P670XB output.
6. Check for 100 mV reading on voltmeter, ±8%. (The 1310 nm Conversion
Gain is 1.00 V/mW.)
AC Conversion Gain
1. Connect the probe under test to the 11K series oscilloscope and to the cal
source.
HIf the unit under test is a P6701B, connect the 850 nm modulated laser
source to the optical attenuator input. Connect the output of the optical
attenuator to the P6701B input via an inline adapter.
HIf the unit under test is a P6703B, connect the 1310 nm modulated laser
source to the optical attenuator input. Connect the output of the optical
attenuator to the P6703B input via an inline adapter.
2. Adjust the laser cal source to provide a 10KHz to 20KHz optical square
wave on the scope. Adjust the optical attenuator so that the total peak-to-
peak signal from the P670XB is about 200 mV (or 200 W if the vertical
units displayed are “W”).
P6703B