Tektronix 7934 User manual

OPERATORS / Part No. 070-5879-00
TE
MANUAL
Product
Group
No.
42
7934
OSCILLOSCOPE
The following service instructions are for use by quali-
fied personnel only. To avoid personal injury, do not
perform any service other than that contained in op-
erating instructions unless you are qualified to do so.
Refer to Operators Safety Surnmary and Service
Summary prior to performing any service.
Please Check for
CHANGE INFORMATION
at the Rear of This Manual
First Printing MAY 1986 &
Tektronix.
COMMITTED TO EXCELLENCE

Copyright © 1986 Tektronix, Inc. All rights reserved.
Contents of this publication may not be reproduced in
any form without the written permission of Tektronix,
Inc,
Products of Tektronix, Inc. and its subsidiaries are
covered by U.S. and foreign patents and/or pending
patents.
TEKTRONIX, TEK, SCOPE-MOBILE, and @ are
registered trademarks of Tektronix, Inc.
Printed in U.S.A. Specification and price change
privileges are reserved.
Tektronix, Inc.
P.O. Box 500
Beaverton, Oregon 97077 Serial Number.

7934 Operators
TABLE OF CONTENTS
Page Page
LIST
OF
ILLUSTRATIONS...
0.0..c.
cece
eee
es
ii
Section2
OPERATING
INSTRUCTIONS
(cont)
LIST OF TABLES... ccc ccescececeeueeeees ii
OPERATORS SAFETY SUMMARY.............- iv TRIGGERING ............. 000 ce 2-8
7934 FEATURES 00... eee eee vi READOUT..... 000.0000 c cece es 2-8
BEAMFINDER. «00.0.0. 0.0s0s0eee 29
Section 1. GENERAL INFORMATION CALIBRATOR .. 0.0.0.0 ccece sees 29
INTRODUCTION . 2.00... 00eee eee 11 Z-AXIS INPUT. «seen 28
OPERATOR'S MANUAL........... 14 STORAGE OPERATION oso: 28
INSTRUCTION MANUAL 1 DETAILED OPERATING INFORMATION 2-14
INSTALLATION 22... 00. 0c eee cee 11 GRATICULE «sesso serene eee a4
INITIAL INSPECTION... 00002005 1-4 LIGHT FILTER. «wove eeeee eres at
OPERATING POWER INEORMATION 1.2 CONTROL ILLUMINATION. ........ 211
POWER CORD INFORMATION ..... 1-2 INTENSITY CONTROLS. ....... att
OPERATING VOLTAGE ........... 12 DISPLAY FOCUS | «1s. oe soos e 22
OPERATING TEMPERATURE ...... 4-2 ASTIGMATISM AND FOCUS
OPERATING POSITION ..........- 42 ADJUSTMENTS. «2-0 +s 2se sss a2
PACKAGING FOR SHIPMENT 42 BEAMFINDER. ..0..0.0..0-000005 2-12
SPECIFICATION .....0..0.0c0ec cues 1-4 TRACE ALIGNMENT ............ a12
ELECTRICAL CHARACTERISTICS... 1-4 READOUT DISPLAY... ...- 4... 242
ENVIRONMENTAL tat READOUT IDENTIFY ...........-. 2013
PHYSICAL ‘ie READOUT INTENSITY...........- 213
SYSTEM ELECTRICAL SPECIFICATION 1-13 READOUT MODES woos 218
PLUG-IN INCOMPATIBILITIES. ..... 4-14 READOUT OPERATION WITH
7934 OSCILLOSCOPE VERTICAL STORAGE |... s serene 218
SYSTEM SPECIFICATION. ...... 4-46 NORMAL READOUT MODE... .. 218
7934 OSCILLOSCOPE HORIZONTAL BISTABLE AND VAR PERSIST 2-14
SYSTEM SPECIFICATION. ...... 4-17 FAST BISTABLE AND FAST
SPECIAL PURPOSE PILUG-IN UNITS 1-18 VAR PERSIST ..... 0... 214
STANDARD ACCESSORIES ......... 4-19 PULSED READOUT MODE...... at4
RECOMMENDED ACCESSORIES... 4-49 BISTABLE .....-.... + 0-005 214
VAR PERSIST......0.0-.0-- 214
Section 2. OPERATING INSTRUCTIONS FAST BISTABLE ..«-- +. +++. etd
FAST VAR PERSIST. ........ 2-14
PLUG-IN UNITS. oo... eee eee 2-1 READOUT WITH SAVE STORAGE
INSTALLATION OF PLUG-IN UNITS . 2-1 MODE .....-..s. ss ceceaees 244
CONTROLS AND CONNECTORS ..... 2-1 SAVE WITH NORMAL
FRONT-PANEL COLOR CODING ... 2-1 READOUT............... 2-14
OPERATOR'S CHECKOUT SAVE WITH PULSED
PROCEDURE ................04. 2-1 READOUT........0.....- 2-14
TEST EQUIPMENT REQUIRED... 24 REDUCED SCAN MODE.......... 214
PRELIMINARY SET UP........... 26 STORAGE DISPLAY.............. 2-14
DISPLAY FOCUS «20... 0.0. ee eee 27 BISTABLE STORAGE .......... 244
TRACE ALIGNMENT ............. 27 VARIABLE PERSISTENCE
GRATICULE ILLUMINATION ....... 2.7 STORAGE... cscs cscs 244
CONTROL ILLUMINATION. 00.0... 2-7 FAST STORAGE .............. 2.45
VERTICAL DEFLECTION SYSTEM... 2-7 ERASE.............0seeee. 2-15
HORIZONTAL DEFLECTION SAVE MODE «0.0... cee ces eens 245
SYSTEM... cee eee eens 2-7 CARE OF STORAGE SCREEN ..... 2-16

7934 Operators
Page
Section 2 OPERATING INSTRUCTIONS (cont)
VERTICAL AND HORIZONTAL MODE
COMBINATIONS .............-, 2-16
VERTICAL MODES .............. 2-16
LEFT OR RIGHT .............. 2-16
ALTERNATE MODE............ 2-16
CHOPPED MODE ............. 2-17
ALGEBRAIC ADDITION......... 2-17
HORIZONTAL MODES............ 2-18
AOR Boo. eee eee 2-18
ALTERNATE MODE............ 2-18
CHOPPED MODE ............. 2-18
HORIZONTAL SELECTION ...... 2-18
VERTICAL TRACE SEPARATION ... 2-18
TRIGGER SOURCE .............. 2-18
CALIBRATOR OUTPUT ........... 2-19
VOLTAGE 2.66. eee 2-19
CURRENT .... 0... eee ee eee 2-19
REPETITION RATE ............ 2-19
WAVE SHAPE, .....--.- creas 2-19
SIGNAL OUTPUTS. ...........54- 2-19
+ SAWTOOTH OUT........... 2-19
+ GATE OUT... eee eee 2-19
VERTICAL SIGNAL ............ 2-19
PROBE POWER............... 2-20
DISPLAY PHOTOGRAPHY......... 2-20
INTENSITY MODULATION......... 2-20
REMOTE INPUT SIGNALS ........ 2-20
REMOTE RESET INPUT. ....... 2-24
REMOTE ERASE INPUT........ 2-21
REMOTE SAVE INPUT......... 2-21
TABLE OF CONTENTS (cont)
REMOTE STORAGE GATE INPUT 2-21
Page
Section 2 OPERATING INSTRUCTIONS (cont)
APPLICATIONS ......00.00 00002 2-21
VERTICAL AMPLIFIER PLUG-IN
UNITS. 00 cece ees 2-21
SINGLE-TRACE.............., 2-21
DUAL-TRACE. ...........00 008 2-21
THREE-TRACE ...........005. 2-21
FOQUR-TRACE .......0,..00005 2-21
TIME-BASE PLUG-IN UNITS....... 2-21
SAMPLING DISPLAYS...........- 2-22
SINGLE-TRACE SAMPLING ..... 2-22
DUAL-TRACE SAMPLING. ...... 2-22
X-¥ SAMPLING .. 0.0.0.0 22 eee 2-22
SPECIAL PURPOSE PLUG-IN UNITS 2-22
DIGITAL COUNTERS AND
MULTIMETER PLUG-IN UNITS 2-22
READOUT ACCESS PLUG-IN
UNIT. 22... 2-22
TRANSISTOR CURVE-TRACER
PLUG-IN UNIT. .........-0-. 2-22
SPECTRUM ANALYZER PLUG-IN
UNITS ©... 00... 2-23
X-Y OPERATION. ........0.- 0006 2-23
RASTER DISPLAYS........--.6-- 2-23
Section 3 INSTRUMENT OPTIONS
OPTION 02 1.2... cece eee eee 3-1
OPTION 03 066... cee eee eee 3-1
CHANGE INFORMATION

LIST OF ILLUSTRATIONS
Fig.
No. Page
FRONTISPIECE. 7934 FEATURES ....... vi
1-1. 7934 DIMENSIONAL DRAWING.......... 1-12
2-1. FRONT-PANEL CONTROLS, CONNEC-
TORS, AND INDICATORS. ..........+-. 2-2
2-2. REAR-PANEL CONTROLS AND
CONNECTORS. ..0 eee 2-4
2-3. DEFINITION OF GRATICULE MEASURE-
MENT LINES..........0.....0...0005- 2-11
2-4. LOCATION OF READOUT ON THE CRT
IDENTIFYING THE ORIGINATING PLUG-IN
AND CHANNEL... ...............000005 2-13
2-5. LOCATION OF READOUT ON THE CRT
WHEN REDUCED SCAN IS SELECTED... 2-13
LIST OF TABLES
Table
No. Page
1-1. POWER-CORD CONDUCTOR IDENTIFICA-
TION, Coc cece eee ence eee tne 1-2
1-2. POWER-CORD AND PLUG
IDENTIFICATION... 00.0... 0 eee eee 1-3
1-3. SHIPPING CARTON TEST STRENGTH.... 1-3
1-4, ELECTRICAL CHARACTERISTICS. ...... 1-4
1-5. ENVIRONMENTAL. ...............0005 1-11
1-6. PHYSICAL. 0. occ eee eee 1-12
1-7. PLUG-IN INCOMPATIBILITIES. .........- 4-14
1-8. 7934 OSCILLOSCOPE VERTICAL SYSTEM
SPECIFICATION, «0.000000 cece eee ene 1-16
1-9. 7934 OSCILLOSCOPE HORIZONTAL
SYSTEM SPECIFICATION. ............- 1-17
1-10. SPECIAL PURPOSE PLUG-IN UNITS..... 1-18
2-1. DISPLAY COMBINATIONS..........2565 2-16
3-1. OPTION INFORMATION LOCATOR....... 3-2
7934 Operators

7934 Operators
OPERATORS SAFETY INFORMATION
The following general safety information applies to all operators and service personnel. Specific warnings will be found
throughout the’ manual where they apply and should be followed in each instance.
WARNING statements identify conditions or practices which could result in personal injury or loss of life.
CAUTION statements identify conditions or practices which could result in damage to the equipment or other property.
The word DANGER on the equipment identifies areas of immediate hazard which could result in personal injury or loss of life.
The following safety symbols may appear on the equipment.
A CAUTION-——-Refer to manuai
¥ DANGER—High voltage
ee) Protective ground (earth) terminal
This instrument operates from a single-phase power source. it has a three-wire power cord and a two-pole, three-terminal
grounding-type plug. The voltage to ground (earth) from either pole of the power source must not exceed the maximum rated
operating voltage—250 volts.
Other warning symbols where they apply.
AC Power Source and Connection
Before making connection to the power source, determine that the instrument is adjusted to match the voltage of the power
source, and has a suitable two-pole, three-terminal grounding-type connector. Refer any changes to qualified service
personnel.
Grounding the Instrument
This instrument is safety class | equipment (IEC designation). All accessible conductive parts are directly connected through
the grounding conductor of the power cord to the grounding contact of the power connector.
The power-input plug must only be inserted in a mating receptacle with a grounding contact. Do not defeat the grounding
connection. Any interruption of the grounding connection can create an electric-shock hazard. Refer to qualified service
personnel for verification of adequate protective grounding system to which this instrument is to be connected.
For electric-shock protection, the grounding connection must be made before making connection to the instrument’s input or
output terminals.
Do Not Remove instrument Covers
To avoid electric-shock hazard, operating personnel must not remove the protective instrument covers. Component replace-
ment and internal adjustments must be made by qualified service personnel only.
Do Not Remove CRT implosion Shield
Do not remove the clear plastic implosion shield covering the ert face plate. This crt implosion shield provides protection to the
operator from crt implosion.

7934 Operators
Do Not Operate in Explosive Atmosphere
To avoid explosion, do not operate this instrument in an explosive atmosphere unless it has been certified for such operation.
Refer fuse replacement to qualified prersonnel only. To avoid fire hazard, use only the fuse specified in the parts list for your in-
strument and which is identical in the following respects:
Use the Proper Fuse
A. Type: Slow blow, fast blow, etc.
8. Voltage rating: 250 V, etc.
C. Current rating.
Operating-Power Considerations
To prevent damage to the instrument always check the LINE VOLTAGE SELECTOR switch, located on the rear of the
instrument, before connecting the instrument to the supply circuit.
Exercise Care with intensity Level
Crt phosphor damage can occur under adverse conditions. Avoid any condition where an extremely bright, sharply-focused
dot
exists on the ert. Also, remember that the light filter reduces the apparent light output from the crt.
Prevent Instrument Damage
Plug-in units should not be installed or removed without first turning the instrument power off, to prevent instrument damage.

7934 Operators
7934 FEATURES
The Tektronix 7934 Storage Oscilloscope is a solid-state, wide-bandwidth instrument designed for fast-writing speed
storage applications. Three display modes are available — Nonstore, Store, and Save; as well as four storage modes —
Bistable, Variable Persistence, Fast Bistable, and Fast Variable Persistence. In addition, the Reduced Scan feature increases
the stored-writing speed capability.
The 7934 accepts up to four Tektronix 7000-series plug-in units. The flexibility of the plug-in feature and variety of plug-in
units available allows the system to be used for many measurement applications. The left pair of plug-in compartments are
reserved for vertical deflection and the right pair are reserved for horizontal deflection. Electronic switching between each pair
produces multi-trace vertical and/or horizontal displays.
Power supply voltages are closely regulated to maintain instrument performance when variations in line voltage, line
frequency, or plug-in load occur. The light-weight, high-efficiency power supply operates from 115- or 230-volt nominal supply
sources (50 to 400 hertz).

Section 1—7934 Operators
GENERAL INFORMATION
INTRODUCTION
Operator’s Manual
The Operator's Manual is divided into three main
sections.
Section 1 — General information contains instrument
description, electrical specifications, environmental charac-
teristics, standard and recommended accessories, installa-
tion, and instructions for packaging for shipment.
Section 2 — Operating Instructions contains informa-
tion relative to operating and checking the instrument
operation.
. Section 3 — Instrument Options contains a description
*. of available options and gives the location of the associated
information for those options.
Instruction Manual
The Instruction Manual contains both operating and ser-
vicing information for the 7934 Storage Oscilloscope. Sec-
tions 1 through 3 of the Instruction Manual contain the same
information as Sections 1 through 3 of the Operator's Man-
ual; the remaining sections of the Instruction Manual are as
follows:
The additional sections of the Instruction Manual con-
tain servicing instructions. These servicing instruc-
tions are for use by qualified service personnel only.
To avoid electric shock or other personal injury, do
not perform any servicing other than that described in
the Operating instructions unless you are qualified.
Section 4 — Theory of Operation contains basic and
general circuit analysis to help in understanding the opera-
tion of the instrument and that may be useful for servicing
the instrument.
Section 5 —~ Maintenance describes routine and correc-
tive maintenance procedures with detailed instructions for
replacing assemblies, subassemblies, and individual compo-
nents.
Section 6 — Checks and Adjustments contains proce-
dures to check the operational performance and electrical
characteristics of the instrument. Procedures also include
methods for adjustment of the instrument to meet
specifications.
Section 7 — Replaceable Electrical Parts contains in-
formation necessary to order replaceable paris and assem-
blies related to the electrical functions of the instrument.
Section 8 — Diagrams and Circuit Board Iliustrations
includes detailed circuit schematics, locations of assembled
boards within the instrument, voltage and waveform in-
formation, circuit board and schematic component locators,
and locations of adjustments to aid in performing the adjust-
ment procedure.
Section 9 — Replaceable Mechanical Paris includes
information necessary to order replaceable mechanical
parts and shows exploded drawings which identify
assemblies.
INSTALLATION
initial Inspection
This instrument was inspected both mechanically and
electrically before shipment. it should be free of mars or
scratches and should meet or exceed all electrical specifica-
tions. To confirm this, inspect the instrument for physical
damage incurred in transit and test the electrical perfor-
mance by following the Operator's Checkout Procedure in
the Operating Instructions, Section 2, and the Performance
Check given in Checks and Adjustments, Section 6 of the
instruction Manual. If there is damage or deficiency, contact
your local Tektronix Field Office or representative.
1-1

General Information—7934 Operators
Operating Power Information
This Instrument can be operated from either a 115-volt or
230-volt nominal supply source, 48 to 440 hertz.
CAUTION
To prevent darnage to the instrument, always check
the setting of the LINE VOLTAGE SELECTOR switch
located on the rear panel of the instrument before
connecting the instrument to the supply circuit.
WARNING
AC POWER SOURCE AND CONNECTION, This in-
sirument operates from a single-phase power source.
it has a three-wire power cord and two-pole, three-
terminal grounding-type plug. The voltage to ground
(earth) from either pole of the power source must not
exceed the maximum rated operating voltage — 250
volts.
GROUNDING. This instrument is safety class | equip-
ment (IEC designation). All accessible conductive
parts are directly connected through the grounding
conductor of the power cord to the grounding contact
of the power plug.
The power input plug must only be inserted in a mat-
ing receptacle with a grounding contact. Do not defeat
the grounding connection. Any interruption of the
grounding connection can create an electric shock
hazard.
For electric shock protection, the grounding connec-
tion must be made before making connection to the
instrument's input or output terminals.
Power Cord Information
A power cord with the appropriate plug configuration is
supplied with the 7934. If you need to change the power
plug, refer to Table 1-1 and Table 1-2 for power-cord and
plug identification information.
Table 1-1
POWER-CORD CONDUCTOR IDENTIFICATION
Conductor Color Alternate Color
Ungrounded (Line) Brown Black
Grounded (Neutral) Blue White
Grounded (Earthing) Green-Yellow Green-Yellow
Operating Voltage
The LINE VOLTAGE SELECTOR switch (located on the
rear panel) allows selection of 115-volt or 230-volt nominal
line voltage operation. To convert from 115-volt to 230-volt
operation, change the power cord and plug to match the
power-source receptacle. Then use a smail screwdriver to
move the LINE VOLTAGE SELECTOR switch to the desired
range.
Operating Temperature
The 7934 can be operated where the ambient air tem-
perature is between 0 and +50° C. This instrument can be
stored in ambient temperatures from —55 to +75° C. After
storage at temperatures outside the operating limits, allow
the chassis temperature to reach a safe operating limit be-
fore applying power.
The 7934 is cooled by air drawn in through holes in the
top, side, and bottom panels and blown out through the fan
exhaust. To ensure proper cooling of the instrument, main-
tain the clearance provided by the feet on the bottom and
allow at least two inches clearance (more if possibie) at the
top, sides, and rear of the instrument.
Operating Position
A bail-type stand, mounted on the bottom of the instru-
ment, permits the instrument to be tited up about 10° for
more convenient crt viewing.
PACKAGING FOR SHIPMENT
lf the 7934 is to be shipped for long distances by com-
tnercial transportation, it is recommended that the instru-
ment be repackaged in the original manner. The carton and
packaging material in which your instrument was shipped
should be saved and used for this purpose.
Also, if this instrument is to be shipped to a Tektronix
Service Center for service or repair, attach a tag to the in-
strument showing the following: Owner of the Instrument
(with address), name of a person at your firm who can be
contacted if required, complete instrument type and serial
number, and a detailed description of the service required.
if the original packaging is unfit for use or is not available,
package the instrument as follows:
1. Obtain a corrugated cardboard shipping carton having
inside dimensions at least six inches greater than the instru-
ment dimensions. Refer to Table 1-3 for carton test strength
requirements.