Tektronix 455 User manual

Tektronix*
455/A2/B2
PORTABLE
OSCILLOSCOPE
WITH OPTIONS
I N S T R U C T I O N M A N U A L

Tektronix, Inc.
P.O. Box 500
Be verton, Oregon
070-1907-01
Product Group 40
Tektronix
COMMITTED TO EXCELLENCE
PLEASE CHECK FOR CHANGE INFORMATION
AT THE REAR OF THIS MANUAL.
455/A2/B2
PORTABLE
OSCILLOSCOPE
WITH OPTIONS
I N S T R U C T I O N M A N U A L
97077 Seri l Number
__________________
First Printing MAR 1975
Revised OCT 1983

Copyright © 1975 Tektronix, Inc. All rights reserved.
Contents of this public tion m y not be reproduced in ny
form without the written permission of Tektronix, Inc.
Products of Tektronix, Inc. nd its subsidi ries re covered
by U.S. nd foreign p tents nd/or pending p tents.
TEKTRONIX, TEK, SCOPE-MOBILE, nd re
registered tr dem rks of Tektronix, Inc. TELEQUIPMENT
is registered tr dem rk of Tektronix U.K. Limited.
Printed in U.S.A. Specific tion nd price ch nge privileges
re reserved.
INSTRUMENT SERIAL NUMBERS
E ch instrument h s seri l number on p rtel insert, t g,
or st mped on the ch ssis. The first number or letter
design tes the country of m nuf cture. The l st five digits
of the seri l number re ssigned sequenti lly nd re
unique to e ch instrument. Those m nuf ctured in the
United St tes h ve six unique digits. The country of
m nuf cture is identified s follows:
B000000 Tektronix, Inc., Be verton, Oregon, USA
100000 Tektronix Guernsey, Ltd., Ch nnel Isl nds
200000 Tektronix United Kingdom, Ltd., London
300000 Sony/Tektronix, J p n
700000 Tektronix Holl nd, NV, Heerenveen,
The Netherl nds

TABLE OF CONTENTS
P ge
List of Illustrations iv
List of Tables v
Safety Su ary vii
OPERATOR S INSTRUCTIONS
SECTION 1 — SPECIFICATIONS
455 Main Module 1-1
A2 Vertical Module 1-5
B2 Horizontal Module 1-7
Reco ended Accessories 1-11
SECTION 2 — OPERATING INSTRUCTIONS
Operating Voltage 2-1
Safety Infor ation 2-1
Functions of Controls, Connectors, and Indicators 2-1
455 Main Module 2-1
A2 Vertical Module 2-3
B2 Horizontal Module 2-5
Basic Applications and Measure ents 2-8
Peak-to-Peak A plitude Measure ents 2-8
Instantaneous A plitude Measure ent 2-8
Dual Trace Phase Difference Measure ent 2-8
High Resolution Phase Measure ent 2-9
Co on Mode Rejection 2-10
Cascaded Operation 2-10
Ti e Duration Frequency Measure ents 2-10
Riseti e Measure ents 2-11
Differential Ti e Measure ents 2-11
Delayed Sweep Magnification 2-13
SECTION 3 — PERFORMANCE CHECK
Options 3-1
Test Equip ent Required 3-1
Preli inary Procedure 3-2
Perfor ance Check Procedure 3-2
SERVICING INSTRUCTIONS
FOR QUALIFIED SERVICE PERSONNEL ONLY
SECTION 4 — CIRCUIT DESCRIPTION
Basic Circuit Functions 4-1
455 Main Module 4-1
A2 Vertical Module 4-1
B2 Horizontal Module 4-2
Detailed Circuit Operation 4-3
Calibrator 4-3
Multivibrator 4-3
Output A plifier 4-3
Horizontal Output A plifier 4-3
Sweep Gate A plifier 4-3

455/A2/B2
TABLE OF CONTENTS (cont)
SECTION 4 — CIRCUIT DESCRIPTION (cont) P ge
Crt Circuit 4-4
High-Voltage Oscillator 4-4
High-Voltage Regulator 4-4
High-Voltage Circuitry 4-5
Crt Control Circuits 4-5
Z Axis A plifier 4-5
Low-Voltage Power Supply 4-5
Power Input 4-5
Secondary Circuit 4-6
Channel 1 and Channel 2 Input Circuits 4-7
Scale Factor Control 4-7
Input Coupling and Volts/Division Switching 4-7
FET Input Source Follower 4-7
Vertical Prea plifier and Switching 4-7
Prea plifier and Channel Switching Gates 4-7
Channel Switching Multivibrator 4-10
Vertical Output A plifier 4-11
Delay-Line Driver 4-11
Nor al Trigger Pickoff 4-11
Vertical Output A plifier 4-11
Trigger Input 4-12
Trigger Coupling 4-12
Input Source Follower 4-12
Trigger, Sweep, and Horizontal Prea plifier 4-12
A and B Trigger Generators 4-12
Sweep Generator IC's 4-15
Miller Sweep Generator 4-15
Sweep Control 1C 4-16
Sweep Control Operation 4-17
A Sweep Mode 4-17
B Dly'd Sweep Mode 4-18
A Inten Sweep Mode 4-18
Horizontal Prea plifier 1C 4-19
SECTION 5 — MAINTENANCE
Cabinet Re oval 5-1
Preventive Maintenance 5-1
Cleaning 5-1
Interior 5-1
Switch Contacts 5-2
Exterior 5-2
Crt 5-2
Visual Inspection 5-2
Lubrication 5-2
Se iconductor Checks 5-2
Recalibration 5-2
Corrective Maintenance 5-3
Obtaining Replace ent Parts 5-3
Standard Parts 5-3
Special Parts 5-3
Ordering Parts 5-3

455/A2/B2
TABLE OF CONTENTS (cont)
SECTION 5 — MAINTENANCE (cont) P ge
Soldering Techniques 5-3
Co ponent Re oval and Replace ent 5-4
Rear Panel Asse bly Re oval 5-4
Cabinet Botto Re oval 5-4
Interconnecting Cable and Pin Connector
Replace ent 5-4
Shaft-Knob Re oval 5-6
Cathode Ray Tube (Crt) Re oval 5-6
Vertical Module Re oval 5-7
Scale-Factor LED Replace ent 5-7
VOLTS/DIV Switch Asse bly Re oval 5-9
Substrate or Contact Replace ent
Considerations 5-9
Actuator Asse bly Replace ent
Considerations 5-9
Hybrid 1C Re oval 5-10
Horizontal Module Re oval 5-11
Board Locations 5-11
A and B Ti ing Switch Board Re oval 5-12
Trigger Board Re oval 5-13
Horizontal Board Re oval 5-13
Troubleshooting 5-14
Troubleshooting Aids 5-14
Troubleshooting Chart 5-14
Diagra s 5-14
Circuit Board Illustrations 5-14
Co ponent Value Identification 5-14
Se iconductor Lead Configurations 5-14
Troubleshooting Equip ent 5-14
Troubleshooting Techniques 5-16
Check Control Settings 5-16
Check Associated Equip ent 5-16
Check Instru ent Calibration 5-16
Visual Check 5-16
Isolate Trouble to a Circuit 5-16
Check Circuit Board Interconnections 5-16
Check Voltages and Wavefor s 5-16
Check Individual Co ponents 5-16
Repair and Readjust the Circuit 5-17
Repackaging For Ship ent 5-20
SECTION 6 — ADJUSTMENTS
Tolerances 6-1
Adjust ent Interaction 6-1
Partial Procedures 6-1
Test Equip ent Required 6-1
A. Main Module 6-3
Preli inary Procedure 6-3
Procedure 6-3
B. Vertical Module 6-6
C. Horizontal Module 6-10
in
REV. C, NOV. 1977

TABLE OF CONTENTS (cont)
SECTION 7 — INSTRUMENT OPTIONS
SECTION 8 — REPLACEABLE ELECTRICAL PARTS
SECTION 9 — DIAGRAMS AND CIRCUIT BOARD
ILLUSTRATIONS
SECTION 10 — REPLACEABLE MECHANICAL PARTS
Accessories
CHANGE INFORMATION
LIST OF ILLUSTRATIONS P ge
Fig. 1-1. Di ensional drawing. 1-4
Fig. 1-2. Trigger coupling and sensitivity. 1-7
Fig. 1-3. Differential Ti e Measure ent accuracy. 1-10
Fig. 2-1. 455 Main Module (front). 2-1
Fig. 2-2. 455 Main Module (rear). 2-2
Fig. 2-3. A2 Vertical Module. 2-3
Fig. 2-4. B2 Horizontal Module. 2-5
Fig. 2-5. Peak-to-peak voltage easure ent. 2-8
Fig. 2-6. Instantaneous voltage easure ent. 2-8
Fig. 2-7. Phase difference. 2-9
Fig. 2-8. High-resolution phase difference. 2-9
Fig. 2-9. Co on- ode rejection. 2-10
Fig. 2-10. Ti e duration. 2-11
Fig. 2-11. Riseti e. 2-11
Fig. 2-12. Ti e duration between points on a wavefor . 2-12
Fig. 2-13. Ti e difference between pulses. 2-12
Fig. 2-14. Delayed Sweep agnification. 2-13
Fig. 3-1. A plitude calibrator test setup. 3-3
Fig. 3-2. Fast-rise pulse generator test setup. 3-4
Fig. 3-3. Sine-wave generator test setup #1. 3-5
Fig. 3-4. Low-frequency generator test setup. 3-6
Fig. 3-5. Sine-wave generator test setup #2. 3-7
Fig. 3-6. Ti e- ark generator test setup. 3-10
Fig. 4-1. High-voltage oscillator wavefor relationships. 4-4
Fig. 4-2. Foldback circuit action. 4-6
Fig. 4-3. Attenuator and gain switching sequences. 4-8
Fig. 4-4. Channel Switching gates. 4-9
Fig. 4-5. Trigger 1C functional block diagra . 4-13
Fig. 4-6. Sweep generator 1C functional block diagra . 4-14
Fig. 4-7. Sweep control 1C functional block diagra . 4-17
Fig. 4-8. Sweep operation in A ode. 4-18
Fig. 4-9. Sweep-circuit wavefor relationships. 4-19
Fig. 4-10. Sweep operation in B DLY'D ode. 4-20

455/A2/B2
TABLE OF CONTENTS (cont)
LIST OF ILLUSTRATIONS (cont) P ge
Fig. 5-1. Rear-panel asse bly re oval. 5-4
Fig. 5-2. Cabinet botto re oval. 5-5
Fig. 5-3. Pin connector replace ent. 5-5
Fig. 5-4. Shaft-knob re oval. 5-6
Fig. 5-5. Vertical Module re oval. 5-7
Fig. 5-6. LED replace ent. 5-7
Fig. 5-7. VOLTS/DIV switch disasse bly. 5-8
Fig. 5-8. Hybrid 1C replace ent. 5-10
Fig. 5-9. Horizontal Module re oval. 5-11
Fig. 5-10. Circuit board locations. 5-11
Fig. 5-11. A and B ti ing switch diassse bly. 5-12
Fig. 5-12. Co ponent value identification. 5-15
Fig. 5-13. Troubleshooting chart. 5-18
Fig. 6-1. +32 volt adjust ent location. 6-4
Fig. 6-2. Z axis co pensation adjust ent location. 6-4
Fig. 6-3. Crt and calibrator adjust ent locations. 6-5
Fig. 6-4. Vertical adjust ent locations. 6-9
Fig. 6-5. Sweep adjust ent locations. 6-10
Fig. 6-6A Horizontal and Trigger adjust ent locations
SN B044420-UP. 6-11
Fig. 6-6B. Horizontal and Trigger adjust ent locations
below SN B044420. 6-11
Fig. 6-7. C232 and C233 adjust ent locations. 6-13
Fig. Option 4-1. Partial Power Supply diagra . Option 4 Page 1
Fig. Option 5-1. Block diagra . Option 5 Page 8
Fig. Option 5-2. Inverting/non-inverting a plifier block diagra . Option 5 Page 9
Fig. Option 7-1. Power switch. Option 7 Page 1
Fig. Option 7-2. Dc voltage selector switch and dc input connector. Option 7 Page 2
Fig. Option 7-3. Si plified block diagra . Option 7 Page 3
Fig. Option 7-4. Adjust ent Locations. Option 7 Page 6
LIST OF TABLES
1-1. Electrical (455 Main Module). 1-1
1-2. Environ ental. 1-3
1-3. Physical. 1-3
1-4. Electrical (A2 Vertical Module). 1-5
1-5. Electrical (B2 Horizontal Module). 1-7
3-1. Test Equip ent Required. 3-1
3-2. Vertical Deflection Accuracy. 3-3
3-3. A and B Ti ing Accuracy. 3-10
3-4. A and B Magnified Accuracy. 3-11
3-5. Differential Ti e Accuracy. 3-12
5- 1. Power Supply Tolerance and Ripple. 5-16
6- 1. Test Equip ent Required for Adjust ent Procedure. 6-1
6-2. Low-Frequency Input Co pensation. 6-7
1. Sync Separator Trigger Sensitivity. Option 5 Page 1
1. Option 7 Power Sources. Option 7 Page 2
REV C AUG 1980
V

OPERATORS SAFETY SUMMARY
455/A2/B2
The gener l s fety inform tion in this p rt of the summ ry is for both oper ting nd servicing
personnel. Specific w rnings nd c utions will be found throughout the m nu l where they
pply, but m y not ppe r in this summ ry.
TERMS
In This M nu l
CAUTION st tements identify conditions or pr ctices th t could result in d m ge to the
equipment or other property.
WARNING st tements identify conditions or pr ctices th t could result in person l injury or
loss of life.
As M rked on Equipment
CAUTION indic tes person l injury h z rd not immedi tely ccessible s one re ds the
m rking, or h z rd to property including the equipment itself.
DANGER indic tes person l injury h z rd immedi tely ccessible s one re ds the m rking.
SYMBOLS
In This M nu l
This symbol indic tes where pplic ble c ution ry or other inform tion is to be
found.
As M rked on Equipment
yDANGER — High volt ge.
Protective ground (e rth) termin l.
ATTENTION — refer to m nu l.
Power Source
This product is intended to oper te from power source th t will not pply more th n 250 volts
rms between the supply conductors or between either supply conductor nd ground. A
protective ground connection by w y of the grounding conductor in the power cord is
essenti l for s fe oper tion.