Tektronix 7B53A User manual

Tektronix, Inc.
P.O. Box 500
Beaverton, Oregon 97077
070-1342-01
Product Group 42
lI!ktron~
COMMITTED TO EXCELLENCE
PLEASE CHECK FOR CHANGE INFORMATION
AT THE REAR OF THIS MANUAl.
7B53A/7B53AN
DUAL TIME BASE
INSTRUCTION MANUAL
/;< 1/:;-" t?~ ,)'-
First Printing SEP 1980
Revised MAY 1988

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Copyright @) 1972, 1980 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. TELEQUIPMENT
is a registered trademark of Tektronix U.K. Limited.
Printed in U.S.A. Specification and price change privileges
are reserved.
INSTRUMENT SERIAL NUMBERS
Each instrument has a serial number on a panel insert, tag,
or stamped on the chassis. The first number or letter
designates the country of manufacture. The last five digits
of the serial number are assigned sequentially and are
unique to each instrument. Those manufactured in the
United States have six unique digits. The country of
manufacture is identified as follows:
BOOOOOO
100000
200000
300000
700000
Tektronix, Inc., Beaverton, Oregon, USA
Tektronix Guernsey, Ltd., Channel Islands
Tektronix United Kingdom, Ltd., London
Sony/Tektronix, Japan
Tektronix Holland, NV, Heerenveen,
The Netherlands

7B53A/7B53AN
TABLE OF CONTENTS
Page
LIST OF ILLUSTRATIONS ................... . iii
LIST OF TABLES .......................... . iv
OPERATORS SAFETY SUMMARY ............ . v
SERVICE SAFETY SUMMARY ................ . vii
Section 1 SPECIFICATION. . . . . . . . . . . . . . . . .. 1-1
Section 2 OPERATING INSTRUCTIONS. . . . . . .. 2-1
Controls and Connectors .... . . . . . .. 2-1
Operating Checkout ..... . . . . . . . . .. 2-3
General Operating Instructions. . . . .
.. 2-6
Applications. . . . . . . . . . . . . . . . . . . .
.. 2-13
Repackaging for Shipment . . . . . . . .
.. 2-20
I WARNING I
The remaining portion of this Table of Contents lists the
servicing instructions. These servicing instructions are for
use
by qualified personnel only. To avoid electrical shock,
do
not perform anyservicing otherthan that called out in the
operating instructions unless qualified to do so.
Section 3 THEORY OF OPERATION
3-1
Simplified Block Diagram. . . . . . . . . 3-1
Circuit Operation .................. 3-3
Main Trigger
Preamp. . . . . . . . . . . . . .. 3-4
Main Trigger Generator
(SN B210000
& Up 7B53A Only) . . . . . . . . . . . . . . . .. 3-4
Main Trigger Generator (SN B209999
& Below) . . . . . . . . . . . . . . . . . . . . . . . .. 3-7
Main Sweep
Generator. . . . . . . . . . . .. 3-9
Delayed Trigger Generator
(SN B210000 & Up 7B53A Only) . . . .. 3-12
REV DEC 1982
Section 3 THEORY OF OPERATION
(cont'd)
Delayed Trigger Generator
Page
(SN B209999 & Below). . . . . . . . . . . .. 3-12
Delayed Sweep Generator . . . . . . . .
.. 3-12
Horizontal Preamp. . . . . . . . . . . . . . .
.. 3-17
Readout Switching
.... . . . . . . . . . . .. 3-18
Section 4 CALIBRATION. . . . . . . . . . . . . . . . . . .. 4-1
Test Equipment Required .. . . . . . . . .. 4-1
PART 1 PERFORMANCE CHECK. . .. 4-6
Trigger System Check. . . . . . . . . . . .
.. 4-7
Horizontal System Check . . . . . . . . .
.. 4-13
PART 2 ADJUSTMENT
............ 4-20
Trigger System Adjustment.
........ , 4-21
Horizontal System Adjustment. . . . . .. 4-24
Section 5 MAINTENANCE. . . . . . . . . . . . . . . . .. 5-1
Preventive Maintenance. . . . . . . . . . .. 5-1
Troubleshooting. . . . . . . . . . . . . . . . . .. 5-2
Corrective Maintenance
............ 5-4
Section 6 OPTIONS. . . . . . . . . . . . . . . . . . . . . . .. 6-1
Section 7 REPLACEABLE ELECTRICAL PARTS
Section 8 DIAGRAMS AND CIRCUIT BOARD
DESCRIPTIONS
Section 9 REPLACEABLE MECHANICAL PARTS

7B53AJ7B53AN
LIST OF ILLUSTRATIONS
Fig.
No.
2-1
2-2
2-3
2-4
2-5
2-6
2-7
2-8
2-9
2-10
2-11
2-12
2-13
2-14
2-15
2-16
3-1
3-2
3-3
3-4
3-5
3-6
3-7
3-8
3-9
4-1
Page
7B53A17B53AN Dual Time Base ........ viii
Location of release latch. ........... 2-1
Front-panel controls and connectors. . .. 2-2
Frequency range of each COUPLING
switch position. .................. 2-7
Effect
of LEVEL control and SLOPE switch
on CRT display. . . . . . . . . . . . . . . . . .. 2-9
Composite Time/Division switch ....... 2-10
Area
of graticule used for accurate time
measurements. . . . . . . . . . . . . . . . . . .. 2-11
Operation of Sweep Magnifier. ....... 2-11
(A)
Intensified Sweep display; (B) Delayed
Sweep display .................. " 2-12
Typical Mixed Sweep display (DELAYTIME
MUL T dial set to 3.55) .............. 2-12
DELAY TIME MUL T dial. Reading shown
3.55 ........................... 2-12
Measuring the time duration between
points on a waveform. . . . . . . . . . . . .
.. 2-15
Measuring risetime ................ 2-16
Measuring time difference using delayed
sweep
........................ " 2-17
Using delayed sweep
for magnification. 2-18
Displaying a complex signal using delayed
sweep. . . . . . . . . . . . . . . . . . . . . . . .
.. 2-19
Measuring pulse jitter. ............. 2-20
7B53A17B53AN Simplified Block Diagram. 3-2
Trigger Preamp and Input Switching Block
Diagram. . . . . . . . . . . . . . . . . . . . . . .. 3-5
Main
Trigger Generator Block Diagram
(SN B210000 and up 7B53A only) ...... 3-6
Main
Trigger Generator Block Diagram
(SN B209999 and below). ........... 3-8
Main Sweep
Generator Block Diagram. 3-10
Delayed
Trigger Generator Block Diagram
(SN B210000 and up 7B53A only) ...... 3-13
Delayed
Trigger Generator Block Diagram
(SN B209999 and below) ............ 3-14
Delayed Sweep
Generator Block Diagram. 3-15
Horizontal Preamp Block Diagram ..... 3-17
Location of Delayed Gate Out and Variable
Selector mUlti-pin connectors ......... 4-2
@ JUN 1980
Fig.
No. Page
4-2
4-3
4-4
4-5
Typical delay time error measurement. .. 4-16
Typical Delay Time Error Figures ...... 4-17
Allowable Delay Time Error .......... 4-17
Typical CRT display when checking sweep
length. . . . . . . . . . . . . . . . . . . . . . . .
.. 4-25
4-6
5-1
5-2
Typical CRT display for adjIIIstment of Dly'd
Sweep Start and Dly'd Sweep Stop. . . .. 4-26
Location of pins on interface connector .. 5-3
Cam
Switch Removal. . . . . . . . . . . . . .. 5-7
The illustrations in Section 8 are located near their
associated diagrams on the foldout page.
8-1 Electrode configuration for
semiconductors in the instrument.
8-2 Location of circuit boards in the
7B53A17B54AN.
8-3 Partial
A1-lnterface circuit board
component locator (SN B090000 and up).
8-4 Partial A
1-lnterface circuit board
component locator (SN B089999 and
below).
8-5
A2-Source Switch circuit board
8-6
8-7
8-8
8-9
8-10
8-11
8-12
8-13
8-14
component locator.
A3-Coupling Switch circuit board
component locator.
Partial
A4- Trigger circuit board
component locator 7B53A only
(SN B210000 and up).
Partial
A4- Trigger circuit board
component locator (SN B209999 and
below).
Partial
A6-Sweep circuit board
component locator (SN B090000 and up).
Partial
A6-Sweep circuit board
component locator (SN B089999 and
below).
A5-Mode Switch circuit board.
Partial
A4- Trigger circuit board
component locator 7B53A only
(SN B210000 and up).
A7-Delayed Trigger Switch circuit board
com ponent locator.
Partial A4- Trigger circuit board
component locator (SN B209999 and
below).
iii

7B53A17B53AN
Fig.
No.
8-15
8-16
8-17
8-18
8-19
8-20
iv
LIST OF ILLUSTRATIONS (cont)
Fig.
No.
Partial A6-Sweep circuit board
component locator (SN 8090000 and up).
Partial A6-Sweep circuit board
component locator (SN 8089999 and
below).
8-21 Partial A6-Sweep circuit board
component locator (SN 8089999 and
below).
Partial A1-lnterface circuit board (7853A
only) component locator.
Partial A1-lnterface circuit board
(7853AN only) com ponent locator.
A8-Readout circuit board (7853A only)
component locator.
8-22
8-23
8-24
Partial A6-Sweep circuit board
component locator (SN 8090000 and up).
Location of adjustments in the
7853A17853AN (SN 8209999 and below).
Location of adjustments in the 7853A
(SN 8210000 and up).
8-25
Location of adjustments in the
7853A17853AN.
Partial A6-Sweep circuit board
component locator (SN 8090000 and up).
LIST OF TABLES
Table
No.
1-1
1-2
1-3
2-1
2-2
4-1
4-2
4-3
4-4
4-5
5-1
Page
Electrical ....................... 1-1
Environmental ................... 1-6
Physical ....................... 1-6
Deflection Factor of the X Signal ...... 2-13
Risetime Measurements
............ 2-16
Test
Equipment . . . . . . . . . . . . . . . . .. 4-3
Main Sweep
Timing ............... 4-13
Delayed Sweep
Timing ............. 4-14
Main Sweep
Magnifier Accuracy ...... 4-15
Delayed Sweep
Magnifier Accuracy .... 4-15
Relative
Susceptibility to Static Discharge
Damage ........................ 5-2
@ JUN 1980

OPERATORS SAFETY SUMMARY
The general safety information in this part of the summary is for both operating and servicing personnel. Specific
warnings and cautions will be found throughout the manual where they apply, but may not appear in this summary.
TERMS
IN THIS MANUAL
CAUTION statements identify conditions or practices that could result in damage to the equipment or other property.
WARNING statements identify conditions or practices that could result in personal injury or loss of life.
AS MARKED ON EQUIPMENT
CAUTION indicates a personal injury hazard not immediately accessible as one reads the marking, or a hazard to
property including the equipment itself.
DANGER indicates a personal injury hazard immediately accessible as one reads the marking.
SYMBOLS
IN THIS MANUAL
Static-Sensitive Devices.
This symbol indicates where applicable cautionary or other information is to be found.
AS MARKED ON EQUIPMENT
~ DANGER-High voltage.
ffi_
'-:::=:) Protective ground (earth) terminal.
& ATTENTION-refer to manual.
WARNINGS
POWER SOURCE
This product is intended to operate in a mainframe connected to a power source that will not apply more than 250 volts
rms between the supply conductors or between either supply conductor and ground. A protective ground connection by
way of the grounding conductor in the mainframe power cord is essential for safe operation.
GROUNDING THE PRODUCT
This product is grounded through the grounding conductor of the mainframe power cord. To avoid electrical shock, plug
the mainframe power cord into a properly wired receptacle before connecting to the product input or output terminals. A
protective ground connection by way of the grounding conductor in the mainframe power cord is essential for safe
operation.
REV JAN 1985 v

7B53A17B53AN
DANGER ARISING FROM LOSS OF GROUND
Upon loss of the protective-ground connection, all accessible conductive parts (including knobs and controls that may
appear to be insulating), can render an electric shock.
DO NOT OPERATE IN EXPLOSIVE ATMOSPHERES
To avoid explosion, do not operate this product in an atmosphere of explosive gases unless it has been specifically
certified for such operation.
DO NOT OPERATE PLUG-IN UNIT WITHOUT COVERS
To avoid personal injury, do not operate this product without covers or panels installed. Do not apply power to the plug-in
unit via a plug-in extender.
vi
@ JUN 1980

7B53A17B53AN
SERVICING SAFETY SUMMARY
FOR QUALIFIED SERVICE PERSONNEL ONLY
Refer also to the preceding Operators Safety Summary
DO NOT SERVICE ALONE
Do not perform internal service or adjustment of this product unless another person capable of rendering first aid and
resuscitation is present.
USE CARE WHEN SERVICING WITH POWER ON
Dangerous voltages exist at several points in this product. To avoid personal injury. do not touch exposed connections
and components while power is on.
Disconnect power before removing protective panels. soldering. or replacing components.
POWER SOURCE
This product is intended to operate in a mainframe connected to a power source that will not apply more than 250 volts
rms between the supply conductors or between either supply conductor and ground. A protective ground connection by
way of the grounding conductor in the mainframe power cord is essential for safe operation.
@ JUN 1980 vii

7B53A/7B53AN
--
---
-• •
II ~ II
-
iii
IJ
..
.. -•
II iii
• -.
..
..
-'
---
-
-
-
-
---
1342 · 01
The 7B53 A/ 7B53AN Duat Tlm e Base.
viii
@ JUN 1980

Section 1-7B53A17B53AN
SPECIFICATION
NOTE
The 7B53A and 7B53AN are electrically identical except that only the 7B53A is compatible with the
alphanumeric readout system provided for the 7000-series oscilloscopes.
This instrument will meet the electrical characteristics listed under Performance Requirement in Table 1-1, following
complete calibration. The following electrical characteristics apply over an ambient temperature range of 0° C to +50° C,
except as otherwise indicated. Warmup time for given accuracy is 20 minutes.
Characteristics
MAIN SWEEP
Sweep Rates
Sweep Accuracy
Over Center Eight Divisions
50 ms/div to 0.5 j1s/div
5
s/div to 0.1 s/div and
0.2 j1s/div to 0.05 j1s/div
------
.-
Over any 2 div portion within
center eight div (all sweep
rates)
Variable Sweep Rates
Sweep Hold-Off
REV D JUN 1980
Table 1-1
ELECTRICAL
Performance Requirement
0.05 j1s/div to 5 s/div in 25 calibrated
steps.
Measured
in 7000-Series Oscilloscopes.
+15°C to +35°C O°C to +50°C
Unmag Mag Unmag Mag
Within Within Within Within
2% 2.5% 3% 4%
Within Within
Within
Within
3%
3.5% 4%
5%
-
Within Within
5%
7%
Continuously variable between cali-
brated sweep rates. Extends sweep rate
to at least 12.5 s/div.
Hold-off time may be varied at least
2:1 by front-panel VARIABLE control
when Variable Selector connector
(P140) is connected for variable
holdoff.
Supplemental Information
Variable to at least 2.5:1. VARIABLE
control internally switchable between
variable main sweep rates, variable
delayed sweep rates, and variable
main sweep holdoff.
._--
1-1

Specification-7B53A17B53AN
Table 1-1 (cont)
Characteristics Performance Requirement Supplemental Information
DELAYED SWEEP
Sweep Rates 0.05 j.ls/div
to .5 s/div in 22 calibrated
steps.
Sweep
Accuracy
Measured in 7000-Series Oscilloscopes.
Over Center 8 Divisions
+15°C to +35°C O°C to +50°C
Unmag Mag Unmag Mag
50 ms/div to 0.5 j.ls/div Within Within Within Within
Exclude the first and beyond the 9th
3%
3.5%
4%
5% division of the unmagnified sweep when
measuring magnified or unmagnified
0.5 s/div to 0.1 s/div and Within
Within Within Within
accuracy.
0.2 j.ls/div to 0.05 j.ls/div 4% 4.5% 5%
6%
Over any 2 div portion within Within Within
center eight div (all sweep
6%
8%
rates)
Variable Sweep Rate
Continuously variable between Extends sweep rate
to at least
calibrated sweep rates. 1.25 s/div. Variable
to at least
2.5:1. VARIABLE control switchable
between variable main sweep rates,
variable delayed sweep rates, and
variable main sweep holdoff.
MIXED SWEEP, VARIABLE
TIME DELAY
Mixed Sweep
Accuracy
Main Sweep
Within 2% plus main sweep error. Exclude
the following portions of
the mixed sweep:
"._. -- .. -
Delayed Sweep Unchanged. First 0.5 div
after start of main
sweep
display and 0.2 div or 0.1 j.lS
(whichever is greater) after transition
of main to delayed sweep.
Variable Time Delay
Delay
Time Range a
to 10 times DLY TIME/DIV
Full scale is 10 times the TIMEIDIV
settings from 5 s/div to 1 j.ls/div. OR
DL Y TIME setting. Accuracy applies
overthe center eight major DELAYTIME
MUL T dial divisions.
Differential Delay
Time
Measurement Accuracy
(+15°C to +35°C)
5 s/div to 1 s/div
Within 1.4% of measurement plus
0.3% of full scale.
0.5
s/div to 1 j.ls/div
Within 0.7% of measurement plus
0.3% of full scale.
Delay Time
Jitter at Less
than 1 part in 20,000 of 10X
1 ms/div
the TIMEIDIV setting.
1-2 REV A
JUN 1980
---------------------~=~~~------~~--~~-~~~-~.-~ ... - .. ----

Specification-7B53A17B53AN
Table 1-1 (cont)
Characteristics Performance Requirement Supplemental Information
AMPLIFIER
Deflection Factor I
EXT, MAG X10 10
mV/div within 10%.
EXT,
MAG X1 100 mV/div within 10%.
EXT + 10,
MAG X1 1 v/div within 10%.
Nominal Frequency Response System
-3 dB points in 7000-Series
Oscilloscope.
Lower -3 dB Upper -3 dB
AC
40 Hz 2 MHz
AC LF REJ 16 kHz 2
MHz
AC HF REJ 40 Hz 100 kHz
DC DC 2
MHz
MAIN TRIGGERING
Trigger Sensitivity
COUPLING
Minimum Trigger
Triggering Signal Required
Frequency Range
INT' EXT
(div) {mY)
AC
30 Hz to
0.3 100
10 MHz
10 MHz to
1.5 500
100
MHz
AC LF REJ 30 kHz to
0.3 -
10 MHz
150 kHz
Triggering signal amplitude require-
-100 ments increased 10
times for
10 MHz
EXT -;. 10 operation.
10
MHz
1.5 500
to 100 MHz
AC HF REJ 30 Hz to
0.3 100
50 kHz
DC
dcto
0.3 100
10 MHz
10 MHz to
1.5 500
100
MHz
----
REV JAN 1985 1-3

Specificati on-7BS3A/7BS3AN
Table 1-1 (cont)
Characteristics Performance Requirement Supplemental Information
External Trigger Input
Input
Rand C
Approximately 1 MO paralleled by
20 pF.
Maximum Safe Input Voltage
500 V (de + Peak ae). 500 V peak-
to-peak ae at 1 kHz or less.
Level Range
EXT
At least + and -1.5 V.
EXT 710
At least + and - 15 V.
Internal Trigger Jitter
1 ns or less at 75 MHz.
DELAYED TRIGGERING
Trigger Sensitivity
Minimum Trigger
Triggering Signal Required
Coupling
Frequency Range
INT'
EXT
(div) (mV)
AC
30 Hz to
0.3 100
10
MHz
10 MHz to
1.5 500
100
MHz
DC de to
0.3 100
10
MHz
10 MHz to
1.5 500
100
MHz
External Trigger Input
Maximum Safe Input
500 V (de + peak ae). 500 V peak-
Voltage (DLY'D TRIG
to-peak ae at 1 kHz or less.
SOURCE set to EXT)
Input Rand C 1
MO paralleled by 20 pF.
Level Range
At least + and -1.5 V.
Internal Trigger Jitter
1 ns or less at 75 MHz.
1-4 REV A JUN 1980

Specificati on-7BS3A/7BS3AN
Table 1-1 (cont)
Characteristics Performance Requirement Supplemental Information
OUTPUT SIGNALS
Delayed Sweep Gate
Maximum Safe
Input
±10 V (dc + Peak ac). 20 V peak-
Voltage to-peak ac at 1 kHz or less.
Waveshape Rectangular pulse.
Amplitude
~3.0 V with baseline at -0.2
Available at front-panel DLY'D
to -1 V when loaded by at least 10 kO. TRIG IN
connector when
~0.475 with baseline at 0 to
operating in the INTEN, DLY'D
-0.2 V when loaded by 50 O.
SWP, or MIXED Display Modes.
The DLY'D TRIG SOURCE switch
must
be set to I NT and P613 must
be connected for Delayed Sweep
Gate Out.
Output Resistance
Approximately 350 O.
Loading At least
10 kO shunted by 100 pF
or less.
Polarity Positive-going.
Duration
DISPLAY MODE
INTEN, DLY'D SWP For the
time that the delayed sweep runs.
MIXED
Composite gate signal with timing de-
termined by the setting
of the TIMEI
DIV OR DLY TIME switch
during the
main sweep
portion of the display,
and by
the setting of the DLY'D Time/
Division switch during the delayed
sweep
portion of the display.
Sweep Gate Refer
to associated oscilloscope manual.
Duration
DISPLAY
MODE
MAIN SWEEP, INTEN Coincident with the main sweep interval. .
DLY'D SWP
Coincident with the main sweep inter-
val.
MIXED
Coincident with the main sweep interval
plus the delayed sweep interval.
.0.
Main Sweep Gate Refer
to associated oscilloscope manual.
Duration
Coincident with the main sweep (all
Display Modes).
@ JUN 1980 1-5

Specificati on-7853A17853AN
Table 1-1 (cont)
Characteristics Performance Requirement Supplemental
Information
Sawtooth Refer
to associated oscilloscope manual,
Waveshape
DISPLAY MODE
MAIN SWP, INTEN Sawtooth signal
with slope determined
by setting of
the TIMEIDIV OR DLY
TIME switch.
DLY'D SWP Sawtooth signal
with slope determined
by
the setting of the DLY'D Time/
Division switch.
MIXED
Composite sawtooth signal with slope
determined by
the setting of the
TIMEIDIV OR DLY TIME switch during
the main sweep portion of display, and
by
the setting of the DLY'D Time/
Division switch during the delayed
sweep
portion of display.
Duration
Coincident with the time that each
sweep is displayed.
• For Internal Triggering only, the specified -3 dB frequency of the vertical system replaces any frequencies in the above table
when the number in the table is greater than the -3 dB frequency of the vertical system.
Characteristics
Size
Weight
1-6
Table 1-2
ENVIRONMENTAL
Refer to the Specification for the associated oscilloscope.
Table 1-3
PHYSICAL
Description
Fits all 7000-series plug-in compartments.
3.3 Ibs (1.5 kg).
@ JUN 1980

Section 2-7BS3A/7BS3AN
OPERATING INSTRUCTIONS
7B53A17B53AN Features
The 7B53A and 7B53AN Dual Time Base units provide
Mai n, Intensified, Delayed, and Mixed sweep operation for
TEKTRONIX 700o-Series Oscilloscopes. Calibrated
sweep rates from 5 s/div to 50 ns/div (5 ns with X10
magnification) and triggering to 100 MHz are provided.
The 7B53A and 7B53AN are electrically identical except
that only the 7B53A is compatible with the alphanumeric
readout system provided for 700o-Series Oscilloscopes.
Other features include 0 to 10times continuous sweep
delay,
variable main and delayed sweep rates, and variable
main sweep
holdoff. Separate triggering controls are
provided
for main and delayed sweep triggering, and
when
operating in the AUTO MAIN TRIGGERING MODE,
a bright base line is displayed in the absence of a trigger
signal. The 7B53A17B53AN can also be used as an
amplifier for X-V operation.
General
The 7B53A17B53AN operates with a TEKTRONIX 7000-
Series Oscilloscope and a7A-Series Amplifier unit to form
a complete oscilloscope system. To effectively use the
7B53A17B53AN, its operation and capabilities should be
known.
This section explains the operation of the front-
panel controls and connectors, provides an Operating
Checkout procedure, gives general operating informa-
tion, and describes basic applications for this instrument.
Installation
The 7B53A17B53AN is designed to operate in the
horizontal compartment of the indicator oscilloscope.
This instrument can also be installed in the Vertical plug-in
compartment to provide asweep that runs vertically on the
crt. However, when used in this manner, there are no
retrace
blanking or internal triggering provisions, and the
unit may not meet the specifications given in Section 1.
The instructions in this manual are written for use of the
7B53A17B53AN in the horizontal plug-in compartment.
Before proceeding with installation it is necessary to
check the internal connections of the Variable Selector
connector and the Delayed Sweep Gate Out connector.
These connections should be checked against those
shown in Fig. 4-1 by qualified service personnel.
REV B JUN 1980
To install the 7B53A17B53AN in a plug-in compart-
ment, push it in until it fits firmly into the compartment.
The front panel of the 7B53A17B53AN should beflush with
the front panel of the indicator oscilloscope. Even though
the gain of the indicator oscilloscope is standardized to
minimize adjustment when inserting plug-in units, the
sweep calibration of the 7B53A17B53AN should be check-
ed when installed. The procedure for checking the unit is
given
under Sweep Cali bration in the 0 perating Checkout
procedure in this section.
To remove the 7B53A17B53AN, pull the release latch
(see Fig. 2-1) to disengage the unit from the indicator
oscilloscope and pull it out of the plug-in compartment.
RELEASE
LATCH
OLV'O TRIG
LEVEL
DELAY TIME MULT
I"". TRIG "
OR
AMP IN
~ ' .. " .....
'C 7B53~ ___ D_UA __ LT .... IM_E ___ I
Fig. 2-1. Location of release latch.
CONTROLS AND CONNECTORS
General
All controls required for the operation of the
7B53A17B53AN, except the Variable Selector and the
Dly'd Sweep Gate Out connector are located on the front
panel of the instrument. To make full use of the
capabilities of this instrument, the operator should be
familiar with the function and use of each control. A brief
description of the front-panel controls and connectors is
given here.
More detailed information is given under
2-1

Operating Instructions-7B53A/7B53AN
General Operating Information. Fig. 2-2 shows the front
panel and external controls and connectors of the
7B53A17B53AN.
1. Main Triggering Controls
LEVEL. Selects the amplitude point on the trigger
signal where sweep triggering occurs.
SLOPE. Two-position switch permits triggering on the
positive-going or negative-going
portion of the main
triggering signal.
TRIG'D. Light indicates that the main sweep is
triggered and will
produce a display.
MODE. Pushbuttonswitchesselect
the operating mode
for the main triggering circuits.
CD
0
MAIN
TRIGGERING
CONTROLS
SWEEP
CONTROLS
DELAY
TIME
CONTROL
TIIIG'D
'J:'~~(,,)l7\~
•
COU PLI NG. Pushbutton switches select the method of
coupling the triggering signal to the main triggering
circuits.
SOURCE. Pushbutton switches select the source of the
main
triggering signal.
2. Sweep Controls
TIMEIDIV OR DLY TIME. Selects the sweep rate of the
main sweep generator (see Fig. 2-5).
DLY'D Time/Division. Selects
the sweep rate of the
delayed sweep generator and selects the MAIN SWP,
INTEN, and DLY'D SWP Display Modes (see Fig. 2-5).
VARIABLE. Provides continuously variable main
sweep rates,
continuously variable delayed sweep rates,
MAIN TRIGGERING
AMPLIFIER
MODE COUPLlIIG
SOURCE
AUll)
AC
15T
0 0
It
At Lf RtJ
UNE
~
:!)
At HfREJ
EXT
li)
~
EXT+ID
~
®
DELAYED
TRIGGERING
CONTROLS
INPUT/OUTPUT
CONNECTORS
TEKTRONIX(!' ~
7853A ",," __ DU_A_L_T ... IM ... E_B_A_S_E __ ~ •
Fig. 2-2. Front-panel controls and connectors.
2-2 REV C
JUN 1980

or variable main sweep holdoff; depending on the setting
of the Variable Selector mUlti-pin connector (P140). The
VARIABLE control also selects the MIXED Display Mode
(see Fig. 2-S).
SWP CAL. Screwdriver adjustment to match the gain of
the 7BS3A17BS3AN to the indicator oscilloscope for
calibrated sweep rates.
POSITION. Controls horizontal position of display.
FINE. Provides precise
control of horizontal position
adjustment.
MAG.
Pushbutton switch selects X1 or X10 horizontal
magnification.
3. Delay Time Control
DELAY TIME MUL T. Provides variable sweep delay
between 0.00 and 10.0 times the delay time indicated by
the TIMEIDIV OR DLY TIME switch.
4. Delayed Triggering Controls
LEVEL. Selects the RUNS AFTER DLY TIME or
Triggerable After Diy Time Modes, and the amplitude
point at which the delayed sweep is triggered.
SLOPE. Two-position switch permits triggering on the
positive-going or negative-going portion of the delayed
triggering signal.
COUPLING. Two-position switch selects the method of
coupling the triggering signal to the delayed triggering
circuits.
SOURCE. Two-position switch to select the source of
the delayed triggering signal.
5. Input/Output Connectors
MAIN TRIG IN OR AMP IN. Front-panel bnc connector
serving as an external trigger input for the main triggeri ng
circuit or as an external horizontal input, depending upon
the setting of the TIME/DIV OR DLY TIME switch and the
MAIN TRIGGERING SOURCE switch.
DL Y'D TRIG IN. Front-panel bnc connector serving as
an external trigger input for the delayed triggeri ng circuits
or as a delayed sweep gate output; depending upon the
DLY'D TRIG SOURCE switch, the position of P613, and
the DISPLAY MODE.
REV C JUN 1980
Operati ng I nstructions-78S3A/78S3AN
OPERATING CHECKOUT
Introduction
The following procedure checks the basic operation of
the 7BS3A17BS3AN. It may also be used for familiarization
with this instrument or as an incoming inspection. This
procedure is divided into two parts, Sweep Control
Functions, and Main and Delayed Triggering Functions. A
complete operating check of the 7BS3A17BS3AN control
functions can be made by performing both parts, or each
part may be performed separately.
NOTE
For optimum performance, the 7853A/7853AN
should be installed in an oscilloscope system with
similar frequency and sweep rate capabilities.
Setup Procedure
1. Install the 7BS3A/7BS3AN in the right horizontal
compartment of the indicator oscilloscope.
2. Install a Vertical Amplifier unit in the left vertical
compartment.
3. Turn on the indicator oscilloscope and allow at least
20 minutes warmup.
4. Set the 7BS3A17BS3AN controls as follows:
MAIN TRIGGERING
SLOPE
(+)
MODE AUTO
COUPLING AC
SOURCE
INT
DLY'D TRIG
LEVEL RUNS AFTER
DL Y
TIME (fully clockwise)
SLOPE
(+)
COUPLING AC
SOURCE
INT
Sweep Controls
POSITION Midrange
MAG X1-IN
TIME/DIV OR DLY TIME 1 ms
DL Y'D Time/Division
VARIABLE
Variable Selector
DELAY TIME MUL T
1 ms
CAL (fully clockwise)
Main Variable
1.00
S. Set the indicator oscilloscope to display the pi ug-in
units and
adjust for a well defined display. See indicator
2-3

Operating Instructions-7B53A17B53AN
oscilloscope and vertical unit instruction manuals for
detailed operating instructions.
Sweep Control Functions
The following procedure checks the operation of the
sweep controls and checks the Display Modes.
Normal Sweep
1. Perform steps 1 through 5 of the Setup Procedure.
NOTE
The Time/Division switch selects main sweep rates,
delayed sweep rates, and Display Modes (MAIN
SWP, IN TEN, DLY'D SWP, and MIXED). Refer to
Selecting Sweep Rates and Display Modes dis-
cussions in the General Operating Instructions for
further information.
2. To select the MAIN SWP Display Mode, press in the
DL Y'D Time/Division knob, and set the TIMEIDIV OR DL Y
TIME switch and the DLY'D TimelDivision switch to the
same sweep rate (1 ms).
3. Connect the 1 kHz calibrator signal from the in-
dicator oscilloscope to the vertical amplifier unit Input.
Adjust the Calibrator and the vertical Volts/Division switch
for four divisions of display.
4. Rotate the MAIN TRIGGERING LEVEL control fora
stable MAIN SWP display (non-delayed). Rotate the
DELAY TIME MUL T dial and note that it has no effect on
the display.
5. Rotate the POSITION control and note that it
horizontally positions the trace. Rotate the FI NE control
and note that it provides precise horizontal positioni ng.
Disconnect the calibrator signal.
Sweep Calibration
NOTE
For accurate sweep timing, apply a signal of known
frequency or time period (time-mark signal,
calibrator square wave, 60 Hz line etc.) to the
associated vertical amplifier unit and adjust the
TIME/DIV OR DL Y TIME switch and the SWP CAL
control to calibrate the signal to the oscilloscope
graticule. Be sure that the sweep timing signal is
accurate within 0.5%. The following sweep calibra-
tion procedure uses a TEKTRONIX Time-Mark
Generator.
2-4
6. Connect a 1 ms time-mark signal from the Time-
Mark Generator with a 50 n bnc coaxial cable with bnc
connectors and 50 n bnc termi nation to the I nput of the
associated vertical unit. Adjust the vertical Volts/Div
switch for about four divisions of display and rotate the
MAIN TRIGGERING LEVEL control for a stable display.
Check the crt display for one complete time-mark per
division (position as necessary). If necessary, adjust the
SWP CAL screwdriver adj ustment for one complete time-
mark per division over the center eight divisions of display.
Disconnect the Time-Mark Generator.
Intensified, Delayed, and Mixed Sweep
7. Reconnect the oscilloscope Calibrator signal to the
vertical unit and adjust for about four divisions of vertical
display. Pull
out the DL Y'D Time/Division knob and rotate
clockwise to .1 ms/div for the INTEN Display Mode
(TIMEIDIV OR DLY TIME switch remains at 1 ms/div).
Note that a delaying sweep with an intensified portion
(delayed sweep) is displayed on the crt (the oscilloscope
Intensity may need to be varied to view the intensified
display).
8. Rotate the DELAY TIME MUL T dial and notethat the
amount of delay time before the intensified portion of
display is controlled by the DELAY TIME MUL T dial.
9. Rotate the VARIABLE control counterclockwise out
of switch detent and note that the sweep rate indicated by
the TIME/DIV OR DLY TIME switch can be varied to at
least the sweep rate of the next adjacent position
(2 ms/div). The internal Variable Selector connector must
be set for variable main sweep rates. Return the
VARIABLE control to the CAL position.
10. Press the DLY'D Time/Division switchtotheinner
position for the DLY'D SWP Display Mode. Note the
magnified display with sweep rate determined by the
DL Y' D Time/Division switch. The oscilloscope Intensity
may need to be increased to view the delayed sweep
display.
11. Pull out the VARIABLE Time/Division knob for the
MIXED Display Mode (MIXED Display Mode can be
selected when operating in the DLY'D SWP Display Mode
only). Note that the main sweep is displayed at a rate
determined by the TIME/DIV OR DLY TIME switch
followed by a delayed sweep display at the rate deter-
mined by the DL Y'D Time/Division switch. Rotate the
DELAY TIME MULT dial and note that the amount of
display allocated to each sweep is determined by the
DELAY TIME MULT dial.
REV C JUN 1980