Tektronix 475 User manual

IEIGrcnix
Teklronix, lnc.
P.O. Box 500
Eeaverlon, Oregon gTOTl INSTtrUCT ION
COMMTTTED TO EXCELLENCE
MANUAL
First Printing JULY 1976
07G2039.00 Serial Number
475
oscrLLos
AND
DM44 DIGITAL
MULTIMETER
OPERATORS
E
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Copyright o 1976 Tektronix, lnc. All rights
reserved. Contents ol this publication may not be
reproduced in any form without the written
permission of Tektronix, Inc.
Products of Tektronix. lnc. and its subsidiaries
are covered by U.S. and loreign patents and/or
pending patents.
TEKTRONIX, TEK, SCOPE-MOerLe, anO @
are registered trademarks of Tektronix, lnc.
TELEQUIPMENT is a registered trademark of
Tektronix U.K. Limited.
Printed in U.S.A. Specification and price change
privileges are reserved.
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TABLE OF CONTENTS
BASIC OSCILLOSCOPE DISPLAYS Page
16
LIST OF ILLUSTRATIONS
LIST OF TABLES
CONTROLS, CONNECTORS. AND
INDICATORS
VEBTICAL
DISPLAY
oM44
TRIGGER
HORIZONTAL, CALIBRATOR, AND POWER
BEAR PANEL
LEFT SIDE PANEL
RIGHT SIDE PANEL
NORMAL SWEEP DISPLAY
MAGNIFIED SWEEP DISPLAY
DELAYED SWEEP DISPLAY
MIXED SWEEP DISPLAY
X.Y DISPLAY
SINGLE SWEEP DISPLAY
'16
17
17
18
18
19
4
4
7
7
8
'12
14
14
14
RESISTANCE
VOLTS
TEMPERATURE
Accuracy Check
TIME AND 1/TIME
APPLICATIONS AND MEASUREMENTS
PRELIMINARY
Signal Ground
Input Coupling Capacitor Precharging
20
20
24
24
27
2A
28
28
28
BEV A JAN 1981 475/DM44 Operators
Page
iv
'|
1
1
2
2
2
3
BEFORE OPERATING
INTRODUCTION
SAFETY INFORMATION
OPERATING VOLTAGE
Line Voltage Selection
Regu lating Range Selection
OPTIONS DM44 DISPLAYS AND MEASUREMENTS
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TABLE OF CONTENTS (cont)
APPLTCATTONS AND MEASUREMENTS (cont) Page APPLTCATIONS AND MEASUREMENTS (conr) Page
42
43
44
45
45
46
48
48
OPERATOR'S ADJUSTMENTS AND CHECKS 29
Trace Rotation 29
Probe Compensation 29
Vertical Gain Check 30
Basic 475 Timing Check 30
DM44 Timing Check 30
External Horizontal Gain Check 31
PEAK.TO-PEAK VOLTAGE
MEASUREMENTS-AC
INSTANTANEOUS VOLTAGE
MEASUREMENTS-DC
ALGEBRAIC ADDITION
COMMON MODE REJECTION
AMPLITUDE COMPARISON
MEASUHEMENTS
TIME.DURATION MEASUREMENTS
FREQUENCY MEASUBEMENTS
RISETIME MEASUBEMENTS
TIME DIFFERENCE BETWEEN TWO
PULSES FROM DIFFERENT SOURCES
TIME COMPAHISON MEASUHEMENTS
31
PHASE DIFFERENCE MEASUREMENTS
HIGH RESOLUTION PHASE DIFFERENCE
MEASUREMENTS
PULSE JITTER MEASUREI\,4ENTS
DELAYEO OR MIXED SWEEP
MAGNIFICATION
Magniried Sweep Starts Alter Delay
Triggered Delay Sweep Magnilication
Besic 475 Delayed or Mixed Sweep Time
Measuremenls
TIME DIFFERENCE BETWEEN REPETITIVE
PULSES (BASTC 475)
TIME DURATION MEASUSEMENTS
(BASTC 475)
FREQUENCY MEASUREMENTS (BASIC 475)
TIME DIFFERENCE BETWEEN TWO PULSES
FROM DIFFEHENT SOUHCES (BASIC 475)
RtSETtME (BAStC 475)
Mrx (BASTC 475)
34
35
36
37
39
40
41
49
50
51
52
I 475/OM44 Operators REV A JAN 1981
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TABLE OF CONTENTS (cont)
OM44 Delayed or Mixed Sweep Tlme
Meeaurements
TIME DIFFEBENCE BETWEEN REPETITIVE
PULSES (DM44)
TIME DURATION MEASUREMENTS (DM44)
FREQUENCY MEASUBEMENTS (DM44)
TIME DIFFERENCE BETWEEN TWO PULSES
FFOI\,,l DIFFERENT SOURCES (DM44)
RTSETTME (DM44)
M rx (DM44)
OPERATOR'S SPECIFICATIONS
475 OSCILLOSCOPE
VERTICAL
TRIGGERING
DIFFEHENTIAL TIME IVEASUREMENT
(BASTC 475)
DIFFERENTIAL TIME IVEASUREMENT
(oM44)
HORIZONTAL
x-Y
CALIBRATOF
Page
54 OPERATOR'S SPECIFICATIONS (cont) Page
56
58
Z AXIS INPUT
OUTPUTS
AC POWER SOURCE
ENVIRONMENTAL
58
60
61
DM44 DIGITAL MULTIMETER
RESISTANCE
TIME
1/TIME
TEMPERATUBE
DC VOLTAGE
65
65
65
65
66
66
66
66
66
66
62
62
63
63
ACCESSORTES
STANDAHD ACCESSORIES
OPTIONAL ACCESSORIES
68
68
68
64
64
64
64
OPTIONS
OPTION 1
OPTION 4
OPTION 7
59
69
69
69
475/OM44 Operalors It
REV A JAN 1981
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LIST OF ILLUSTRATIONS
Page Page
Fig. 1
Fig.2
Fig.3
Fig.4
Fi9.5
Fig. 6
Fig. 7
Fis
Fig
Fig
Fis
Fig
Fis
Fis
Fig
Fig
Regulating range selector and line
fuse. 3
Vertical controls, connectors, and
indicators. 4
Display and DM44 controls,
connectors, and indicators. 6
Trigger controls, connectors, and
indicators. I
Trigger controls, connectors, and
indicators. 10
Horizontal, calibrator, and power
controls, connectors, and indicators. 12
Rear panel and lelt side panel controls,
connectors, and indicators. 15
Resistance. 21
Volts. 23
Temperature. 25
Probe compensation. 29
Basic 475 timing check. 30
DM44 timing check. 31
Peak-to-peak voltage of a waveform. 32
lnstantaneous voltage measurements. 33
Algebraic addilion. 35
Common-mode rejection.
Time duration.
Risetime.
Time difterence between two pulses
from dilferent sources.
Phase dilference.
High-resolution phase dif ference.
Pulse jitter.
Delayed sweep magnif ication.
Time dilference between repetitive
pulses.
Time duration.
Time difference between two pulses
lrom dilferent sources.
Risetime.
Time ditlerence between repetitive
pulses.
Time duration and frequency
measurements.
Time dillerence between two pulses
from diflerent sources.
Riselime.
Fig. 17
Fig. 18
Fig. 19
Fig. 20
36
38
39
F ig. 21
Fiq.22
Fig.23
Fig.24
Fig.2s
40
43
43
44
46
49
50
51
53
57
Fig. 26
Fig.27
8.
9.
10
'11
12
'13
14
15
16
s
F
Fis 28
29
Fig. 30
Fig. 31
Fig. 32
56
59
60
@
475/OM44 Operators
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TABLE 1 Regu lating Ranges
TABLE 2 Resistance Ranges
TABLE 3 Volts Ranges
LIST OF TABLES
Page
TABLE 4 Centigrade to Fahrenheit Conversion 26
TABLE 5 DM44 Delayed Sweep Oisplays 54
Page
2
20
22
@415/Dln44 Operalors
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2039-12
2039-t5
475 Oscilloscope with DM44 Dlgital Multlmeter.
475/DM44 Operalors @
Basic 475 Oscilloscope.
1
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The Tektronix 475 Oscilloscope is a dual-channel
portable instrument. The dual-channel dc-to-200 MHz
vertical system provides ca librated deflection factors lrom
2 millivolts to 5 volts,/division. The sweep trigger circuits
are capable of stable triggering over the lull bandwidth
capabilities of the vertical detlection system. The horizon-
tal dellection system provides calibrated sweep rates trom
0.5 second to 0.0'l microsecond/division along wilh
delayed sweep features lor accurate relative-time
measurements. A X1O magnifier extends the calibrated
sweep rate to 1 nanosecond/division. The instrument
operales over a wide variation of line voltages and
frequencies. Maximum power consumption is about
100 watts.
The Tektronix DM44 Digital Multimeter measures O
ohm to 20 megohms, 0 dc vott to 1200 dc volts (+ or -), or
(using the temperature probe) -55oC to +150"C. The
measurement is displayed on a 3-1/2 digital display while
the oscilloscope operates normally.
BEFORE OPERATING
The digital multimeter and oscilloscope combine to
provide a digital readout ot the time between any two
points on the oscilloscope display. Both time measure-
ment points are displayed on the crt at the same time. The
1/TIME function can provide direct measurement ol
frequency.
SAFETY INFORMATION
The instrument is designed to operate lrom a single-
phase power SOUrce with one of the current-carrying
conductors (the Neutral Conductor) at ground (earth)
potential. Operation lrom power sources where both
current-carrying conductors are live with respect to
ground (Such as phase-to-phase on a three-wire system)
is not recommended, since only the Line Conductor has
over-current (tuse) protection within the instrument.
The instrument has a three-wire power cord with a
three-terminal polarized plug for connection to the power
source and safety-earth. The ground (earth) terminal of
the plug is directly con nected to the instrument rrame. For
electric-shock protection, insert this plug only in a mating
outlet with a salety-earth contact.
1
@475/DM44 Operators
INTRODUCTION
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caurtoll
Line vollage Selection
This instrument operates from either a 11s-voll or a
230-volt nominal line voltaqe source, 48 to 440 hertz. To
converl from one nominal line voltage range to the other,
move the Line Voltage Selector switch (located on side
panel) to indicate the correct nominal voltage. A 1.1s-to-
230 volt adapter may be required forthe line-cord plug. Be
sure to use the correct line luse lor the line voltage
selected (see Table 1).
Regulaling Range Seleclion
The Regulating Range Selector assembly (located on
the rear panel) is set for one of the line voltage ranges
shown in Table '1 . lt also contains the line ruse for overload
protection.
To change the regulating range:
'1. Disconnect the inslrument lrom the power source
2. Loosen the two captive screws that hold the cover
on the selector assembly; then pull to remove the cover.
3. Pull out the range selector switch bar (see Fig. l).
Select a range from Table 1 which is centered about the
average line voltage. Slide the bar to the desired position
and plug it in. Push the cover on and tighten the screws.
TABLE 1
Regulating Ranges
Regulating Range
Range Selector
Switch Position
LO (Switch bar in
lower holes) 198 to 242 volts
M (Switch bar in
middle holes)
Hl (Switch bar in
upper holes)
Fuse Size
230-Volls
Nominal
216 to 264 volts
0,75 A 3AG
Fast-blow
2
11s-Volts
Nominal
99 to '121 volts
104 to'126 volts
108 to 132 volts
,I ,5 A 3AG
Fast-blow
475/DM44 Operalors
OPERATING VOLTAGE
This instrument may be damaged it opercted with
the line voltage selector switch or the rcgulating
rcnge selector set for the wrong applied line voltage
ot il the wrong line luse is used.
207 to 253 volts
@
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SELECTOR SWITCH BAR
(SHOWN IN MEDIUI,,l POSITION)
LINE FUSE
1739-1
OPTIONS
Options are available to alter oscilloscope perlormance
to meet particular applications. A number in either IVIOD
slot (see ltem 53, Controls, Connectors, and lndicalors)
indicates a modif ied oscilloscope.
Fig. l- Regulating range seleclor and line fuse.
4751DM44 Operalors 3
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CONTROLS, CONNECTORS AND INDICATORS
VERTICAL
Fi9, 2. Verlical controls, connecto.s, and indicators.
l. CH 1 8nd CH 2 VOLTS/DlV-Selects the vertical
deflection lactor in a 1-2-5 sequence (VAR control must be
in the calibrated d€tent lor the indicated derlection factor).
2. VOLTS/DIV Readoul-Consisls oI two small lamps
Ior each channel, located beneath the skirt of each
VOLTS/DIV knob. One or the other lamp will light up to
indicate the correct dellection lactor when a probe with a
scale-switching connector is used. A probe without this
connector lights the X1 lamp.
3. vAR-Provides continuously variable uncalibrated
deflection factors between the calibrated settings of the
VOLTS/DlV switch, and extends the maximum vertical
deflection to at least 12.5 volts per division (5 volt
position).
4. UNCAL Lamp-lndicates when the VAR
VOLTS/DlV control is out of the calibrated detent and the
vertical deflection lactor is uncalibrated.
@475/OM44 Operalors
5
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4
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3
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6, CH 1 OR X and CH 2 OR y-lnput connectors for
application oI external signals to the inputs of the vertical
amplifier. ln the X-Y mode ot operation, the signal
connected to the cH 1 oFl x connector provides horizon-
tal deflectlon and the signal connecied to the CH 2 OB y
connector provides vertical deflection.
7. AC-cND-DC-Selects the method used to coupte a
signal to the input o, the verticat amplifier. tn the AC
position, signals are capacitively coupled to the vertical
amplif ier. The dc component ol the input signat is btocked.
ln lhe GND position, the input of the vertical amplifier is
disconnected lrom the input connector and grounded to
allow the input coupling capacitor to precharge. ln the DC
position, all components of the input signal are passed to
lhe input amplitier.
8. VERT MODE-Selects mode of operation for ver-
tical amplif ier system.
ADD: Signals applied to the CH 1 and CH 2 input
connectors are algebraically added, and the algebraic
sum is displayed on the crt. The INVERT switch in Channel
2 allows the display to be CH 'l plus CH 2 or CH 1 minus
CH 2. Useful for common-mode rejection to remove an
undesired signal or for dc otfset.
CHOP: Provides duaFtrace display of the signals of
both channels. Display is switched between channels at a
repetition rate ot approximately 250 kHz. Usefutat sweep
rates slower than about 50 microseconds/division, or
when a dual-trace, single-sweep display is requjred.
CH 2: Channel 2 only is displayed. lt musl be selected
in X-Y operation.
9. 100 On 20 MHz BW/TRIG VtEw-Three-purpose
switch that limits lhe bandwidth ol the verlicat amptifier
system to approximately 100 MHz (first detent) or 20 MHz
(second detenl) when pulled. or when pressed, causes the
signal applied to A Trigger Generator to be disptayed on
the crt
10. INVERT-Channel 2 display is inverted in the
INVERT (button in) position.
5
475/DM44 Operalors
5. POSITION-Positions the disptay vertica y. tn the
X-Y mode, the CH 1 POS|TION control positions on the X
axis (horizontalty) and the CH 2 pOStTtON controt
positions on the Y-axis (vertically).
ALT: Provides dual-trace display ol the signals of both
channels. Display is switched between channels at the end
ol each sweep. UseIul at sweep rates taster than about 50
microseconds/division.
CH 1: Channel 1 only is displayed.
@
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23 24
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ON SIDE
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Flg.3. Display.nd DM44 controls, conneclots, and indlcators.
475/Oln44 OPeralorB @
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DISPLAY
11. lnternal Grsllcule-Eliminates parallax. Risetime,
amplitude and measurement points are indicated at the
lert-hand graticule edge.
12. BEAM FINDEn-Compresses the display to within
the graticule area independently of display position or
applied signals and provides a visible viewing level.
13. INTENSITY-Controls brightness of the crt dis-
play.
14. FOCUS-Ad justs ,or optimum display delinition
'15. SCALE ILLUM-Controls graticule illumination
16. ASTIG-Used in coniunction with the FOCUS
control to obtain a well-delined display. lt does nol require
readjuslment in normal use.
17. TRACE BOTATION-Ad justs trace to align with
the horizontal graticu le lines.
DM44
18. lnput ConnecloB-Two banana iacks provide +
(red) and COM (black) inputs for vottage and resistance
on ly.
19. Probe Connector-lnput connector for the
temperature probe.
20. Readout Negative polarity indication is
automat;c for negative dc voltage and temperature wilh no
polarity indication ror positive measurement. A blinking
display indicates overrange. The decimal point is position-
ed by the FUNCTION and RANGE controls for multimeter
operation and by the oscilloscope A TIME/DlV switch in
the TIME or 1/TIME modes.
21. RANGE-Selects trom .2 V to 'l.2 kV dc in 5 ranges
(1200 volts is the maximum safe inpul in the 1.2 kV dc
mode): Irom 200 ohms to 20 megohms in 6 ranges.
22. FUNCTION-Selects VOLTS, OHMS, IEMP ("C),
1/TlME, or TINIE lunctions of the DM44.
23. Scale Faclor Lamps-Two lamps
ln the TIME lunction, the Readout and Scale Factor
Lamps indicate the time dilference belween the two
intensified zones on the crt display. One lamp or the other
will light to indicate ms or ts. No lamp lit indicates
seconds.
ln the 1/TIME function the Readout and Scale Factor
Lamps indicate the number of measured intervals per unit
of time. One lamp or the other will light to ind icate intervals
per ms (1/ms lamp) or intervals per ts (1//ls lamp). No
@475/OM44 Operators 7
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Fig. 4. Trigger controls, conneclors, and lndicalors.
lamp lit indicates intervals per second. It the duration ol
one evenl is being measured, the Readout and Scale
Factor Lamps indicate frequency. The 1/ms lamp in-
dicates kHz, the 1/ts lamp indicates MHz, and no lamp lit
indicates Hz.
24. A TIME-Used in conjunction with the DELAY
TIME POSITION control in the TIME and '1lTIME Iunc-
tions. The A Tll\IE control moves only the time-
measurement point. The DELAY TIME POSITION control
moves both the rererence point and the time-
measurement point. With the time-measurement point to
the left oI the relerence point the Readout indicates a
negative time diflerence. NOTE
You can modily your instrument to make the DELAY
TIME POSITION conttol move only the relerence
point. The procedure fot making this modilication is
located in the Maintenance seclion of lhe DM44
Service manual.
TRIGGER
25. TRIG MODE-Determines the mode of trigger
operation lor A Sweep.
AUTO: Sweep isinitiated bytheappliedtriggersignal.
ln the absence of an adequate trigger signal, or if the
trigger repetition rate is less than about 20 hertz, the
sweep free runs and provides a bright reference trace.
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NOFIM: Sweep is initiated by the applied trigger signal.
ln the absence of an adequate trigger signal, there is no
trace. When the trigger rate is too low for AUTO use
NORM,
SINGL SWP: When this pushbuton is pushed, the A
Sweep operates in lhe single sweep mode. After a single
sweep is displayed, turlher sweeps cannot be presented
untilthe SINGLE swP button is again pushed. lt is useful
when the signal to be displayed is not repetitive or varies in
amplitude, shape or time causing an unstable conven-
tional display. ll can atso be used to photograph a
nonrepetitive signal.
26. READY Lamp-lndicates A Sweep is,,armed,,and,
upon receipt ol an adequate trigger signal, will present a
single-sweep display.
rate for delayed-sweep presentations and low-repetition
rate signals. Use the A trigger controts for the best
possible display before using the A TBlc HOLDOFF
control.
29. COUPLING-Determ ines method used to coupte
signals to the trigger generator circuit.
AC: Signals are capacitively coupled to the inpul of the
trigger generator. Dc is rejected and signals below about
60 Hz are attenuated.
LF REJr Signals are capacitivety coupled to the input
of the trigger circuit. Dc is rejected and signals below
about 50 kHz are attenuated. lt is userul for providing a
stable display of the high-frequency components of a
complex waveform.
27. TBIG Lamp-tndicates that A Sweep is triggered
and will produce a stabte disptay. It is usefut lor setting up
the trigger circuits when a trigger signal is avait;ble
without a display on the crt (tor example, when using
external triggers).
28. A TRIG HOLDOFF-provides conlinuous control
of time between sweeps. Allows triggering on aperiodic
signals (such as complex digital words). tn the fu y
clockwise position (B EN DS A), A sweep is reset at the end
of B sweep lo provide the tastest possible sweep repetition
HF FIEJ: Signals are capacitively coupled to the input
of the trigger circuit. Dc is rejected and signals below
about 60 Hz and above about 50 kHz are attenuated. lt is
useful for providing a stable display of the low-frequency
components of a complex waveform.
DC: All components of a trigger signal are coupled to
the input oI the trigger circuit. lt is useful lor providing a
stable display ol low-lrequency or low-repetition rate
signals, except the combination of the ALT (dual trace)
mode with the trigger SOUBCE switch in NORM.
9
475/DM44 OperatorS
@
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+: Sweep can be triggered ,rom the positive-going
portion oI a trigger signal.
Correct SLOPE setting is important in obtaining a
display when only a portion of a cycle is being displayed.
31. LEVEL-Selects the amplitude point on the trigger
signal at which the sweep is triggered. lt is usually
adjusted lor the desired display after trigger SOURCE,
Flg.5. T,lgger conlrols, connecloB, and lndlcators. COUPLING and SLOPE have been selected
475/Dln44 Operalors @
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30. SLOPE-Selects the slope of the trigger signalthat
starts the sweep.
: Sweep can be triggered trom the negative-going
portion ot a trigger signal.
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32. SOURCE-Oeterm ines the source oI the trigger
signal coupled to the input of the trigger circuit.
NORM; Trigger source is displayed signal(s). lt does
not indicate time relationship between CH 1 and CH 2
signals. However, stable triggering of non-time-related
signals usually can be obtained by setting VERT MODE to
ALT, SOURCE to NORM and COUPLTNG ro LF REJ
Carefully adjust LEVEL lor a stabte display.
CH 1: A sample o, the signal available in Channel 1 is
used as a trigger sagnal. CH 2 signal is unstable it il is not
time-related.
CH 2: A sample of the signat avaitabte in Channet 2 is
used as a trigger signal. CH 1 signat is unstable if it is not
time-related.
LINE (A Trigger circuit only)r A sampte of the power-
line lrequency is used as a trigger signal. lt is uselul when
the input signal is time-related (muttiple or submuttipte) to
the line frequency or when it is desirable to provide a
stable display of a line-frequency component in a complex
wavelorm.
EXT: Signals connected to the External Trigger lnput
connectors are used lor triggering. External signals must
be time-related to the displayed signal lor a stable disptay.
It is uselu I when the internal signal is too smallor contains
undesired signals that could cause unstable triggering. tt
is uselul when operating in CHOP mode.
EXT + 10 (A Trigger circuit only): External trigger
signal is attenuated by a factor of '10.
STARTS AFTER OELAY (B Trigger circuit onty): B
Sweep runs immediately after the detay time selected by
the DELAY-TIME POSITION control. When making
d ilferential time measuremenls you must use th is mode to
obtain valid measurements. On instruments equipped
with a DN444 you must use this mode to obtain valid
measurements when using the TIME or 1/TIME functions.
33. Exlernal Trlgger lnputs-lnput connectors lor ex-
ternal trigger signals.
@475/DM44 Operators 11
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HORIZONTAL, CALIBRATOR, AND
POWER
34a. A AND B TIME/DIV AND DELAY TIME-A
TIME/DlV switch (clear plastic skirt) selects the sweep
rate of the A Sweep circuit tor A sweep only operation and
selects the basic delay time (to be used by the DELAY-
TIME POSITION control) for delayed sweep operation. B
TIME/D lV switch (pull out and rotale to un lock) selects the
sweep rate tor the B Sweep circuit tor delayed sweep
operation only. A VAR control must be in the calibrated
detent for calibrated A Sweep rates. When both TIME/DlV
switches are fully counterclockwise to the X-Y position,
the horizontal (X-axis) display is the CH 1 input.
34b. DM44 A AND B TIME/OIV ANO DELAY TIME-
The controls operate in the same manner as 37a above.
The A TIME/DlV switch also controls the Tl[/E lamps and
decimal point location when the DM44 is in the TIME
Or 1/TIME MODE,
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2039-7
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Fi9. 6. Horizontal, callbrator, and power conlrols, connectors,
and indicators.
35. FINE/POSITION-Positions the display horizontal-
ly lor A sweep and B Sweep.
30. xl0 MAG-Increases displayed sweep rale by a
lactor of 10. lt extends lastest sweep rate to 1
nanosecond/d ivision. The magnified sweep is the cenler
d ivision of the unmagn if ied display (0.5 division either side
ol the center graticule line).
44
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