Tektronix 535A Service manual

TEKTRONIX IN C P.O. BOX 831 PORTLAND 7. OREGON

Copyright © 1959 by Tektronix,
Inc, Portland, Oregon. Printed in
the nited States of America. All
rights reserved. Contents of this
publication may not be reproduced
in any form without permission of
the copyright owner.
INTROD CTION
The following pages provide a
rapid means of setting the controls
of your Tektronix Type 535A or
Type 545A Oscilloscope. This infor
mation is designed to give you
not only control settings for specific
applications but also various func
tions of these controls during differ
ent operational procedures.
An important part of this book
covers "triggered operation of the
oscilloscope. Here, some "trigger
ing" signal starts the horizontal
trace across the screen, beginning
at the left hand side of the grat
icule For present purposes, thon,
■'triggering" can be taken as synon
ymous with starting the horizontal
sweep of the trace.
w> * / msa-i

CONTENTS
Probe Adjustment . ..............................................
Charocteristics of Plug-In and
Type 535A-545A Combinations ................
Selecting tho Triggering Signal ....................
Triggered Operation: A TOMATIC MODE .
Triggered Operation: AC MODE . ........
Triggered Operation: DC MODE ................
Triggered Operation: AC, LF REJECT MODE
Triggered Operation:
sing the Type CA Plug-In nit ...................
Synchronized Operation: HF SYNC MODE .
Free Running Sweep Operation ......................
Delayed Trigger Operation ...........................
Delayed Sweep Operation ...........................
Delayed Sweep Expanded ..............................
Single Sweeps: Manual Operation ..............
Single Sweeps: Triggered Operation ..........
External Sweep Operation ..........................
sing the Variablo STABILITY Control ........ .
Possible Causes for Lack of Trace ................
Operating Description of Controls
and Connectors ...........................................
1
2
3
4
6
8
10
12
14
16
17
18
20
22
24
26
28
29
30
soia/s+sa-i

BEFORE SING PROBE
ALWAYS CHECK ITS ADJ STMENT
PROBE ADJ STMENT
An adjustable capacitor in the probe body compcnsales
for variations in input capacitance from one instrument to
another, so that your pulse and transient measurements will
be accurate Touch the probe tip to the oscilloscope cali
brator output connector and adjust the oscilloscope controls
to display several cycles of the waveform. Adjust the probe
capacitor for a flat top on the calibrator square wave.
S3£AA-lbA- 1

CHARACTERISTICS OF PLUG-IN
AND TYPE 535A/TYPE 545A COMBINATIONS
For the complete list of specifications, including risetime
and input capacitance, see the instruction manual for the
instrument involved.
PL G-IN DEFLECTION FACTOR
(Calibrated) BANDPASS
535A/545A
TYPE A .05 v/cm to 20 v/cm dc to 14 mc/20 me
TYPE B .05 v/cm to 20 v/cm dc to 14 me/12 me
TYPE B 5 mv/cm to .05 v/cm 2 c to 10 mc/dc to 20 me
TYPE CA*
TYPE Dt .05 v/cm to 20 v/cm
1 mv/cm to 50 v/cm dc to 15 mc/24 me
dc to 2 me
TYPE Et 50/tv/cm to lOmv/cm .06 c to 60 kc
TYPE G t .05 v/cm to 20 v/cm dc to 14 mc/20 me
TYPE H 5 mv/cm to 20 v/cm dc to 11 me/15 me
TYPE K .05 v/cm to 20 v/cm dc to 15 mc/30 me
TYPE L 5 mv/cm to 2 v/cm 3 c to 15 mc/24 me
TYPE L .05 v/cm to 20 v/cm dc to 15 mc/30 me
’ Dual-Trace or Single-Traco Differential.
? Differential Input Available.
kWMu-1 j
SELECTING THE TRIGGERING SIGNAL
To trigger the sweep from the waveform being observed,
set the block TRIGGER SLOPE sw.tch to -f INT. or —INT.
2. To trigger the sweep from the power-line wave (to ob
serve a waveform having a lime relationship to the power-
line wave), set the black TRIGGER SLOPE SWITCH to -f
LINE or -LINE
3. To trigger the sweep from an external waveform which
has a time relationship to tho observed waveform, connect
the triggering wave to the appropriate TRIGGER INP T
connector, and set the black TRIGGER SLOPE switch to
+EXT or EXT.
A. If you want the start of the display to occur at a time
when the triggering signal is rising (has a positive slope),
use the -f positions of the black TRIGGER SLOPE switch.
To start the display at a time when the triggering signal is
falling (has a negative slope), use the positions of Ihe
block TRIGGER SLOPE switch.
33Sa/&4&A-I 3

TRIGGERED OPERATION
A TOMATIC MODE
For periodic signals
60 cycles lo 2 megacycles
This mode i» porticularly useful when changing the input
connection from one point in the circuit to another. It pro
vides a trace with or without a triggering signal.
CONTROL POSITION PAGE*
HORIZONTAL DISPLAY A or B 30
TRIGGERING MODE A TO. 31
TRIGGER SLOPE t +IN T or — INT 31
STABILITY NOT SED 31
TRIGGERING LEVEL NOT SED 32
’ Refer» lo description of the control function in this book,
tS ee page 3.
Set the appropriate TIME/CM switch for the desired lime
base and the red VARIABLE knob to CALIBRATED. If the
waveform does not appear, refer to page 29.
u m /mA' i 4
HORIZONTAL DISPLAY ■ lif
In this mode, the red STABILITY knob and the black
TRIGGERING LEVEL control need no adjustment Each
sweep is triggered at the average-voltage point on the
waveform.
•-x a /z^z a - I 5

TRIGGERED OPERATION
AC MODE
For transient or periodic signals
IS cycles to 5 megacycles
This modo is particularly useful for low-frequency signals.
It provides a trace only when a triggering signal occurs.
CONTROL POSITION PAGE*
HORIZONTAL OISPLAY A or B 30
TRIGGERING MODf
---------- .— . ------------ - — — --------
AC 31
TRIGGER SLOPE f + IN T or — INT 31
STABILITY J PRESET 31
TRIGGERING LEVEL Full lof» or right 32
•Rofer* lo description of the control (unction in Shift book.
1See poge 3.
| Click the r*d STABI TY knob M l loll (o PRESET.
1 Set the block TIME/CM switch for tho dosired TIME BASE
and the red VARIABLE knob to CALIBRATED.
2. Turn the black TRIGGERING LEVEL CONTROL slowly
toward the center of its range for a stable display.
If the waveform does not appear, refer to Page 29.
\h a A-.i « i £
In this mode, the black TRIGGERING LEVEL control deter
minos the height on the waveform at which the trace wit
s’arl Triggering is unaffected by the dc components of the
triggering signal or by the VERTICAL POSITION canltol
STAOUTY
HORIZONTAL OISPLAY met
TIME BASE
Atft'OG
wrui
7

TRIGGERED OPERATION
DC MODE
For transient or periodic signals
DC to 5 megacycles
This mode is particularly usoful for signals that change
slowly, signals below the lower frequency limit of the AC
MODE.
CONTROL POSITION PAGE*
HORIZONTAL DISPLAY A o r B 30
TRIGGERING MODE DC 31
TRIGGER SLOPE f + IN T or — INT 31
STABILITY ± PRESET 31
TRIGGERING LEVEL Full fl or right 32
’ Rofen lo deioiption of th« control function in ihi» book,
t Sec page 3.
1 Click tho red STABILITY knob full left lo PRESET.
1. Set the appropriate TIME/CM switch for tho desired time
base, and the red VARIABLE knob to CALIBRATED.
2. Turn the black TRIGGERING LEVEL control slowly toward
the center of its range for a stable display. Final sotting
of this control will depend upon the VERTICAL POSITION
control. If the display is positioned to the top or bottom
of the graticule, the TRIGGERING LEVEL control will be set
to either side of the mid-iongc position. If the waveform
does not appear, refer to page 29.
uia/mM'I 8
In this mode, the black TRIGGERING LEVEL control deter
mines the point on the triggering waveform where triggering
of the sweep occurs. Tho trace always starts at a given
point on the graticule for a given TRIGGERING LEVEL
control setting.
v*.*A«ca-i9

TRIGGERED OPERATION
AC, LF, REJECT MODE
For fromronf or periodic signals,
0 kilocycles lo 5 megacycles
This mode is particularly useful for eliminating undesir
able low-frequency components in the triggering signal.
CONTROL POSITION PAGE*
HORIZONTAL DISPLAY A or B 30
TRIGGERING MODE AC, LF REJECT 31
TRIGGER SLOPE f + IN T or — INT 31
STABILITY $ PRESET
TRIGGERING LEVEL Full loft or right 32
‘ Refer* to description of the control function In this book,
t See page 3.
t Click the red STABILITY knob full left lo PRESET.
1. Set the block TIME/CM switch for the desired time base
and the red VARIABLE knob to CALIBRATED.
2. Turn I he black TRIGGERING LEVEL control slowly to
ward the center of its range for a stable display.
If the waveform does not appear, refer to Page 29.
m a /io a -i 10
This mode Is principally for use with a dual-troco plug-in
unit. However, it may be useful for reducing jitter due to
hum in Ihc Triggering-' signal.
n

TRIGGERED OPERATION
SING THE TYPE CA PL G-IN NIT
For transient or periodic signals,
JO kilocycles to 5 megacycles
Dual-trace operation is possible with the Type CA PL G
IN NIT. In the ALTERNATE position, two traces may be
displayed alternately. In the CHOPPED position, two traces
may bo displayed simultaneously.
CONTROL POSITION PAGE*
HORIZONTAL DISPLAY A or B 30
TRIGGERING MODE AC. LF REJECT 31
TRIGGER SLOPE f +IN T or — INT 31
STABILITY % PRESET 31
TRIGGERING LEVEL Full left or right 32
* Retort to description of the control function in this book,
t See page 3.
t Click the red STABI TY knob full loft to PRESET.
Connect the source of the waveforms to the CHANNEL
A and the CHANNEL B connectors on the plug-in, and place
the MODE switch in the desired position.
2. Set the black TIME/CM switch for the desired time base
and the red VARIABLE knob to CALIBRATED.
3 Turn the black TRIGGERING LEVEL control slowly to
ward the center of its range for a stable display.
If the waveform does not appear, refer to page 29.
ocmiotran
Two waveforms dis
played with ihc Typo
CA Plua-!n nit. The
MODE switch is set at
the ALTERNATE posi
tion.
13

SYNCHRONIZED OPERATION
HF SYNC MODE
For repetitive signals
Above 5 megacycles
In confrost to triggered operation, this mode gives a re
current horizontal sweep which may be synchronized by the
red STABILITY knob.
CONTROL POSITION PAGE*
HORIZONTAL DISPLAY A or B 30
TRIGGERING MODE HF SYNC 31
TRIGGER SLOPE f +IN T or — INT 31
STABILITY Tull right 31
TRIGGERING LEVEL no! used 32
•R efen lo description of the control function In this book,
t Seo page 3.
1. Set the appropriate TIME/CM switch for the desired lime
base and the red VARIABLE knob to CALIBRATED.
2. Turn the red STABILITY knob slowly to the left for a
stable display.
If the waveform does not appear, refer to Page 29.
'.TABI tr
t»*oo«»it.o u m
-0
TIM f BASE
A TOGGttwa Moot tnCCER
HIM
%
L♦
w o
SMBHOT
KIOGIRING VIl
_ -- - ---
TIME BASE
8 T COItlWG MOOI
In this mode, the black TRIGGERING LEVEL control .s
not used. Final sett.ng of the red STABILITY knob depends
upon the nature of the synchronizing signal.
SK*/C4tA- I 15

FREE-RUNNING SWEEP OPERATION
In usual oscilloscope applications, the sweep is
triggered or synchronized by Ihe input waveform.
However, it is possible to use the output from either
of the + GATE connectors or the SAWTOOTH A
connector to trigger or synchronize the input wave
form. Not only does this free running sweep provide
a means for controlling an applied waveform, but
it also supplies a convenient reference trace without
requiring an input signal.
1 se no input to the TRIGGER INP T connector.
2. To free-run the sweep, set the STABILITY knob full right.
3. In all positions of the TRIGGERING MODE switch except
A TO., tho sweep runs at a rote determined by the setting
of the appropriate TIME/CM control. In the A TO, position,
the sweep repetition rate remains at approximately 50
sweeps per second, regardless of the setting of the TIME/CM
control.
If the waveform does not appear, refer to page 29.
.«*/««*■ i 16
DELAYED TRIGGER OPERATION
A delayed triggering pulse can be obtained from
tho DEL'D TRIG, binding-post connector of the oscil
loscope any time from 0.1 microseconds to 50 seconds
after the start of a sweep.
1. Set tho controls of the appropriate time-base unit for
triggered operation or for free-running operation, depending
upon the application.
2. Set the appropriate TIME/CM control and the DELAY
TIME M LTIPLIER control for the delay time.
3. Set the HORIZONTAL DISPLAY switch to any position.
In Ihe A position ond the 'A‘ SINGLE SWEEP position, the
delayed trigger is controlled by TIME BASE A. In the other
positions, the delayed trigger is controlled by TIME BASE
B. In oil positions, an indicator light, located above the
DELAY-TIME M LTIPLIER control, will designate the lime
base used.
If the waveform docs not appear, refer to page 29.
17

DELAYED-SWEEP OPERATION
J T
The deloyed-sweep mode of operation makes pos
sible occurato time and pita so measurements as well
as high magnification of a selected portion of a low
duty-cycle waveform.
1. Set the controls of both time bases for TRIGGERED
OPERATION.
?. Select the delaying sweep by placing the HORIZONTAL
DISPLAY switch in the A1 DEL’D BY B' position.
3. Determine the amount of delay occuring from the ap
plication of the triggering waveform until the sweep runs by
multiplying the settings of the TIME/CM OR DELAY TIME
switch and the DELAY TIME M LTIPLIER control.
NOTE: When the TIME BASE A STABILITY control is turned
full right, the horizontal sweep starts immediately after
completion of the delay period, at a rate determined by
the settings of the TIME BASE A TIME/CM controls. When
the TIME BASE A STABILITY control is not turned full right,
but set with the TRIGGERING LEVEL control for normal
triggering, the horizontal sweep starts after completion of
the delay period, but not until a triggering waveform is
applied to TIME BASE A.
If the waveform does not oppeor, refer to page 29.
I l lM .
tt
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l IO C t8 SlO »t
Sm.
S1AMIT.V
TCiCOfRlNO IJV U
HORIZONTAL DISPLAY
noun
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siAsmrv
toggiuvn
DSa/wSA' 1 19

DELAYED SWEEP EXPANDED
1 Set ihe controls of both time bases for delayed sweep
operation, with the TIME BASE A TIME/CM switch set for
a faster sweep rate than TIME BASE B.
2. Place the HORIZONTAL DISPLAY switch in tho B' IN
TENSIFIED BY 'A' position. The brightened portion (the de
layed sweep] is more noticeable when the INTENSITY con
trol is not turned too high.
3. se the DELAY-TIME M LTIPLIER control to position Ihe
start of the brightened portion (the doloyod sweep) to left
or right.
4. se Ihe TIME BASE A TIME/CM control to adjust the
length of the brighlonod portion (tho delayed sweep) to
part of o cycle or to many cycles.
5. To expand the brightened portion (the delayed sweep)
set Ihe HORIZONTAL DISPLAY switch to the ’A' DEL D BY
"B' position. The amount of magnification is the ratio of
the TIME BASE B TIME/CM OR DELAY TIME control to the
TIME BASE A TIME/CM control.
6. Further magnification may be offccted by the 5X MAG
NIFIER switch.
If the waveform does not oppear, refer to page 29.
20
21

SINGLE SWEEPS
MANUAL OPERATION
Thii mode of operafion per
mits photographing recurrent
phenomena when succeeding
waves are similar but not
necessarily identical.
1 Set the controls of the appropriate time base for free-
running operation.
2 Place the HORIZONTAL DISPLAY switch in the 'A'
SINGLE SWEEP position.
3 After preparing the camera to receive the picture, open
the camera shutter, press the RESET button once, and then
close the camera shutter.
NOTE: Each time the RESET button is pressed, the procedure
is repeated.
u u /mw'I 22
In this mode of operation, the +GATE waveform can be
used to initiate the action to be photographed
■vn*/i 23

SINGLE SWEEPS
TRIGGERED OPERATION
This mode of opcrolion per
mits photographing a single
transient, without interference
from succeeding signals.
t . Set the HORIZONTAL DISPLAY switch to Time-Base A.
Gick the STABILITY knob full left to PRESET. Got a stoblo
display of the signal from the AMPLIT DE CALIBRATOR
connector, whoso amplitude is about that expected of the
desired signal.
2 Select the desired triggering signal. See page 3.
3 Place the HORIZONTAL DISPLAY switch in the ’A'
SINGLE SWEEP position.
4. Remove the lead from the AMPLIT DE CALIBRATOR
connector. Connect the source of expected signal to the
plug in INP T connector. Actuate RESET button. The READY
lamp should light.
5. The next trigger signal received will cause a single trace
to be displayed. The READY lamp will go out.
NOTE: Each time the RESET button is pressed, the procedure
is repeated.
*/*•*•» 24
In this mode of operation, an action occuring at an un
determined time can be photographod
V»a/a5A- 1 25

EXTERNAI SWEEP
This mode of operation uses externally derived
waveforms to deflect the trace both horizontally and
vertically.
1 Connect one externally derived waveform to the input
connector on the plug-in unit for vertical deflection and con
nect the other to the HORIZ. INP T binding post connector
on the oscilloscope for horizontal deflection. The sweep
voltage should not hove a large dc component, or hori
zontal positioning problems may result.
2 Place the HORIZONTAL DISPLAY switch to either EXT.
position.
3. To vary the horizontal deflection factor from approxi
mately .2 volts per centimeter to 15 volts per centimeter,
use tho VARIABLE 10-1 control.
If the waveform docs not appear, refer to page 29.
36
I M M .
TIME BASE
ATOOC.lt
iN*ur
In this mode of operation, set the TRIGGERING MODE
switch to some position other than A TO. Also, set the red
STABILITY lenob as far to the left as possible, without actuat
ing the PRESET switch.
tMA/w«A- I 77

SING THE
VARIABLE STABILITY CONTROL
For o few extremely difficult triggering applications,
a sotting of tho rod STABILITY knob, other than PRE
SET position, is desirable. This may occur in the DC,
AC, or AC, Ur REJECT Modos.
1 Afier setting the oscilloscope controls for the dosired
triggering mode, turn the block TRIGGERING LEVEL control
full right.
2. Turn the red STABILITY knob full right.
3. Slowly turn the red STABILITY knob left until the trace
disappears
4. Slowly turn the black TRIGGERING LEVEL control toward
zero for a stable display.
1. The INTENSITY control is not turned sufficiently to the
right. CA TION: The oscilloscope screen can be damaged
in a few seconds if the spot remains overly long in one posi
tion, or excessively bright.
2. The TIME/CM switch or the flME/CM or DELAY TIME
switch may be set incorrectly.
3. The plug-in vertical-deflection control may bo set in
correctly.
4 The waveform may be off the screen The beam-posi-
tion-indicator lamps will light. Adjust the HORIZONTAL
POSITION control on the oscilloscope, or the VERTICAL
POSITION control on the plug-in, accordingly.
k/t tA'I 29
-1
POSSIBLE CA SES FOR LACK OF TRACE

OPERATING DESCRIPTIONS
OF CONTROLS AND CONNECTORS
HORIZONTAL DISPLAY
The seven position switch determines the time bose
used ond the type of display presented In tho three
TIME BASE A positions, the A sweep is connected to the
horizontal amplifier input. In the two TIME BASE B
positions, the B sweep is connected to the horizontal
amplifier input. In the two EXT. positions, an externally
derived sweep (coupled through the HORIZ INP T con
nector) is connected to the horizontal amplifier input.
In the B position, TIME BASE B is the only sweep. In
the B' INTENSIFIED BY ‘A* position. TIME BASE A is
used to brighten a portion of TIME BASE B. In the 'A'
DEL D BY B' position, the brightened portion, as seen in
the B' INTENSIFIED BY -A' position, will be expanded
the full width of the screen. In the 'A' position, TIME
BASE A is the only sweep. In the A’ SINGLE SWEEP
position, the RESET button controls start of the single
sweep (SEE RESET).
In all positions of the HORIZONTAL DISPLAY switch,
except A' and A- SINGLE SWEEP, the delayed trigger
is controlled by TIME BASE B. In all positions of the
HORIZONTAL DISPLAY switch, the time base used is
indicated by a light above the DELAY-TIME M LTIPLIER
control.
•/««*■ i 30
TRIGGERING MODE (2 switches)
For TIME BASE A, the five position red TRIGGERING
MODE switch selects one of four modes of triggering
(A TO., AC, DC. OR AC. IF RFJECT), plus synchronized
operation (HF SYNC). For TIME BASE B, the three posi
tion switch selects one of three modes of triggering
(A TO.. AC, or DC).
TRIGGER SLOPE (2 switches)
Tho TRIGGER SLOPE switch selocts the swoop trig
gering signal—the signal being displayed (+INT. or
INT.j, an externally derived triggering signal (-fEXT.
or —EXT.), or the power-line wave ( + LINE or—LINE).
In the -f- INT.f -fEXT., or -f-LINE positions, triggering oc
curs during the voltage rise of the triggering waveform.
In the —INT.r —EXT., or —LINE positions, triggering oc
curs during the voltage fall of tho triggering waveform.
STABILITY (2 controls)
The red STABILITY control adjusts the sweep for trig
gered or for free-running operation. When the TRIGGER
ING MODE switch is in the DC or AC positions (also AC,
LF REJECT, in TIME BASE A), the STABILITY control can
generally be used in the PRESET position. When the TRIG
GERING MODE switch is in the A TO, position, the STA
BILITY control is disabled. When the TRIGGERING
MODE switch is in the HF SYNC position (Time Base A),
the STABILITY control serves os the synchronizing control.
For manual operation of the variable STABILITY control,
see page 30.
31

TRIGGERING LEVEL (2 control*)
The TRIGGERING LEVEL control determines the volt
age on the triggering signal at which the horizontal trace
will start. This control is disabled when the TRIGGERING
MODE switch is in the A TO, or HF SYNC positions.
5X MAGNIFIER
The sweep magnifier expands any two centimeter
portion of the displayed waveform the full ten centi
meter width of the graticule. The expanded two centi
meter portion is dotorminod by the setting of the HORI
ZONTAL POSITION switch. When the 5X MAGNIFIER
is turned to ON, the indicator lamp will light
TIME/CM (TIME BASE A >
The twenty-four position TIME/CM switch determines
the sweep speed and the horizontal size of the TIME
BASE A waveform. The CALIBRATED sweep rote is ob
tained only when tho red VARIABLE control is turned
fully clockwise.
VARIABLE (TIME/CM)
The red VARIABLE (TIME/CM) control provides con
tinuous uncalibratod sweep rotos between the ranges of
the TIME/CM switch. The associated NCALIBRATED
indicator lamp will light when the VARIABLE control is
turned away from the CALIBRATED position.
*W m u i 32
TIME/CM OR DELAY TIME (TIME BASE B)
The eighteen position TIME/CM OR DELAY TIME
switch has two functions, depending upon the sotting of
the HORIZONTAL DISPLAY switch. When tho HORI
ZONTAL DISPLAY switch is .n the B or the ,B‘ INTENSI
FIED BY 'A' positions, the TIME/CM OR DELAY TIME
switch determines tho sweep speed and the horizontal
size of the TIME BASE B waveform, When the HORI
ZONTAL DISPLAY switch is in the ‘A’ DEL D BY 'B' posi
tion, the TIME/CM OR DELAY TIME switch determines the
delay time after the triggering signal that TIME BASE A
sweep will run. (See DELAY-TIME M LTIPLIER).
LENGTH (TIME/CM OR DELAY TIME)
The red LENGTH control adjusts the sweep length of
the TIME BASE B waveform between approximately 4
and 10 centimeters. Turning the LENGTH control counter
clockwise reduces the length of the sweep, increases the
duty cycle, and brightens the display. Normally the
LENGTH control is sot fully clockwise.
DELAY-TIME M LTIPLIER M O
The fen turn control multiplies the setting of either the
TIME/CM switch of TIME BASE A, or the TIME/CM OR
DELAY TIME switch of TIME BASE B. An indicator lamp,
located above the DELAY-TIME M LTIPLIER, will light
designating the time base used, according to the setting
of the HORIZONTAL DISPLAY switch.
33