Tektronix 466 User manual

466/464
OSCILLOSCOPES AND
DM44
DIGITAL MULTIMETER

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Tektronix, Inc.
P.O.
Box 500
Beaverton, Oregon
070-2037-00
Product Group 40
97077
lektron~
COMMITTED TO EXCELLENCE
PLEASE CHECK FOR CHANGE
INFORMATION
AT THE REAR
OF THIS MANUAL.
INSTRUCTION
MANUAL
First Printing JUL 1976
Serial Number ______ Revised FEB 1982

Copyright © 1976 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.
TELEOUI
PM ENT 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
Page Page
J LIST OF ILLUSTRATIONS iv DELA
YEO SWEEP DISPLA VS
20
LIST OF TABLES v MIXED SWEEP DISPLAYS
20
X-Y DISPLAYS
21
BEFORE OPERATING SINGLE SWEEP DISPLAY
21
l INTRODUCTION
SAFETY INFORMATION 1 STORAGE DISPLA
VS
22
OPERATING VOLTAGE 2 STORAGE
22
l Line Voltage Selection 2 SAVE STORAGE
22
Regulating Range Selection 2 SAVE RANDOM EVENTS
23
OPTIONS 3 REDUCED SCAN STORAGE (466 ONLY)
23
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CONTROLS, CONNECTORS, AND DM44 DISPLAYS AND MEASUREMENTS
24
INDICATORS
4 RESISTANCE
24
VERTICAL 4 VOLTS
26
] DISPLAY AND STORAGE 6 TEMPERATURE
28
DM44 9 Accuracy Check
28
TRIGGER 10 Low Temperature
28
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HORIZONTAL AND POWER 13 High Temperature
31
REAR PANEL 15 TIME AND 1/TIME
31
RIGHT SIDE PANEL 16
LEFT SIDE PANEL 16 APPLICATIONS AND MEASUREMENTS 32
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BASIC OSCILLOSCOPE DISPLAYS 18 PRELIMINARY 32
NORMAL SWEEP DISPLAY 18 Signal Ground 32
MAGNIFIED SWEEP DISPLAYS 19 Input Coupling Capacitor Precharging 32
J REV FEB 1982 466/464 DM44 Operators
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TABLE
OF
CONTENTS
(cont) !
APPLICATIONS AND MEASUREMENTS (cont) Page APPLICATIONS AND MEASUREMENTS
(cont)
Page
OPERATOR'S ADJUSTMENTS AND CHECKS
33
HIGH RESOLUTION PHASE DIFFERENCE I
Trace Rotation Adjustment 33
MEASUREMENTS 47
Probe Compensation
33
PULSE JITTER MEASUREMENTS 48
Vertical Gain Check
33
DELA YEO OR MIXED SWEEP r
Basic 466/464 Timing Check (60 Hertz
MAGNIFICATION 48
Line Only)
34
Magnified Sweep Starts After Delay 48
DM44 Timing Check (60 Hertz Line Only)
34
Triggered Delay Sweep Magnification 50
External Horizontal Gain Check
35
I
PEAK-TO-PEAK VOLTAGE
MEASUREMENTS-AC
35
INSTANTANEOUS VOLTAGE
BASIC 466/464 DELAYEO OR MIXED SWEEP E
MEASUREMENTS-DC 36 TIME MEASUREMENTS
51
ALGEBRAIC ADDITION
38
TIME DIFFERENCE BETWEEN REPETITIVE
COMMON-MODE REJECTION 39 PULSES (BASIC 466/464)
51
AMPLITUDE COMPARISON
TIME DURATION MEASUREMENTS I
MEASUREMENTS
40
(BASIC 466/464) 52
TIME DURATION MEASUREMENTS
41
FREQUENCY MEASUREMENTS
FREQUENCY MEASUREMENTS
42
(BASIC 466/464) 53 I
RISETIME MEASUREMENTS 42
TIME DIFFERENCE BETWEEN TWO PULSES
TIME-DIFFERENCE BETWEEN TWO FROM DIFFERENT SOURCES
PULSES FROM DIFFERENT SOURCES
43
(BASIC 466/464) 54
TIME COMPARISON MEASUREMENTS
44
RISETIME (BASIC 466/464)
55
I
PHASE DIFFERENCE MEASUREMENTS
46
MIX (BASIC 466/464) 57
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466/464 DM44 Operators
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TABLE OF CONTENTS (cont)
DM44 DELAYED OR MIXED SWEEP TIME Page OPERATOR'S SPECIFICATIONS (cont)
MEASUREMENTS 58 HORIZONTAL
TIME DIFFERENCE BETWEEN REPETITIVE
X-Y
PULSES (DM44) 60 CALIBRATOR
TIME DURATION MEASUREMENTS (DM44)
61
Z AXIS INPUT
FREQUENCY MEASUREMENTS (DM44) 62 OUTPUTS
TIME DIFFERENCE BETWEEN TWO PULSES CH 1
Out
FROM DIFFERENT SOURCES (DM44) 62
A+ and B+ Gates
RISETIME {DM44) 64 AC POWER SOURCE
MIX {DM44) 64 ENVIRONMENTAL
OPERATOR'S SPECIFICATIONS 65 DM44
DIGITAL MULTIMETER
466/464
OSCILLOSCOPE
65 RESISTANCE
STORAGE
65 TIME
Stored Writing Speed 65 1/TIME
Storage View
Time
65 TEMPERATURE
VERTICAL
65 DC VOLTAGE
TRIGGERING
66
Sensitivity 66 ACCESSORIES
External Trigger Input
66 STANDARD ACCESSORIES
INCLUDED
Level Control Range in Ext 67 OPTIONAL ACCESSORIES
Trigger View 67
DIFFERENTIAL
TIME MEASUREMENT OPTIONS
{BASIC 466/464) 67 OPTION 1
DIFFERENTIAL TIME MEASUREMENT OPTION 4
{DM44) 67 OPTION 7
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LIST OF ILLUSTRATIONS m
Page Page
Fig. 1 Regulating range selector and line Fig. 17 Instantaneous voltage measurement.
37
fuse. 3 Fig. 18 Algebraic addition.
38
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Fig. 2 Vertical controls, connectors, and Fig. 19 Common-mode rejection. 39
indicators. 4 Fig.
20
Time duration.
41
Fig. 3 Display and storage controls, Fig. 21
Risetime.
43
connectors, and indicators. 6 Fig.
22
Time difference between two pulses r
Fig. 4 OM 44 controls, connectors, and from different sources.
44
indicators. 8 Fig.
23
Phase difference. 46
Fig. 5 Trigger controls, connectors, and Fig. 24 High-resolution phase difference.
47
E
indicators. 10 Fig.
25
Pulse jitter. 48
Fig. 6 Trigger, horizontal, and power
Fig. 26 Delayed sweep magnification.
49
controls, connectors, and indicators.
12
Fig. 27 Time difference between repetitive E
Fig. 7 Horizontal and power controls, pulses.
52
connectors, and indicators. 14
Fig. 28 Time duration. 53
Fig. 8 Rear panel controls, connectors, and Fig. 29 Time difference between two pulses
indicators.
16 from different sources. 54
E
Fig. SA
Left side panel controls 17 Fig. 30 Risetime.
56
Fig. 9 Tilted operation. 18 Fig.
31
Time difference between repetitive
Fig. 10 Resistance.
25
pulses. 60
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Fig. 11 Volts. 27
Fig. 32 Time duration and frequency
Fig. 12 Temperature 29 measurements.
61
Fig. 13 Probe compensation. 33 Fig. 33 Time difference between
two pulses
Fig. 14 Basic 466/464 timing check. 34 from different sources.
63
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Fig. 15 DM44 timing check 34 Fig. 34 Risetime. 64
Fig. 16 Peak-to-peak voltage
of a waveform. 36
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1982
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TABLE 1 Regulating Ranges.
TABLE 2 Resistance Ranges.
TABLE 3 Volts Ranges.
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LIST OF TABLES
Page
3 TABLE 4 Centigrade to Fahrenheit Conversion
24 TABLE 5 DM44 Delayed Sweep Displays
26
466/464 DM44 Operators
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THE ACCESSORY POUCH ILLUSTRATED SHOULD RE -
MAIN ATTACHED TO THE OSCILLOSCOPE. IT IS DE-
SIGNED
TO KEEP ACCESSORIES READILY AVAILABLE
AND TO AFFORD THE OSCILLOSCOPE SOME PROTEC-
TION IN TRANSIT.
THE ADJUSTABLE CARRYING HANDLE IS DESIGNED
TO OFFER
CONVENIENT STABLE, OPERATING POSI -
TIONS, SUCH AS THOSE
ILLUSTRATED. 2037-16 ,
466/464 DM44 Operators
STORAGE OR OPERATION OF THE OSCILLOSCOPE ON
ITS FOUR REAR FEET IS
NOT DESIRABLE . THE MOST
STABLE OPERATING POSITIONS ARE ILLUSTRATED.
2037-18
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BEFORE OPERATING
INTRODUCTION
The Tektronix 466 and 464 are dual-channel portable
oscilloscopes. The 466 storage system provides storage
for displays with a writing speed up to 3000
divisions/microsecond (in the Fast-Reduced Scan mode).
The 464 storage system does not have the reduced scan
mode and the writing speed is up to 110 divisions/microse-
cond in the Fast mode. The remaining features are
identical. Storage viewtime is greater than 15 seconds at
full-stored display intensity-extending to more than 6
minutes using reduced intensity in the Save mode.
The dual-channel dc-to-100 MHz vertical system
provides calibrated deflection factors from 5 millivolts to 5
volts/division. The sweep trigger circuits are capable of
stable triggering over the full bandwidth capabilities of the
vertical deflection system. The horizontal deflection
system provides calibrated sweep rates from 0.5 second to
0.05 microsecond/division along with delayed sweep
features
for accurate relative-time measurements. A X10
magnifier extends the calibrated sweep rate to 5
nanoseconds/division. The instrument operates over a
wide variation of line voltages and frequencies. Maximum
power consumption is about 100 watts.
The
Tektronix DM44 Digital Multimeter measures 0
ohm to 20 megohms, 0 de volt to 1200 de volts(+ or-), or ,,
(using the temperature probe) -55°C to +150°C. The
measurement is displayed on a 3-1/2 digital display while
the oscilloscope operates normally.
The digital multimeter and oscilloscope combine to
provide a digital readout of 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 of
frequency.
SAFETY INFORMATION
The instrument is designed to operate from a single-
phase power source with one of the current-carrying
conductors (the Neutral Conductor) at ground (earth)
potential. Operation from
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 (fuse) protection within the instrument.
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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 connected to the instrumentframe. For
electric-shock protection, insert this plug
only in amating
outlet with a safety-earth contact.
OPERATING VOLTAGE
This instrument may be damaged if operated with
the line voltage
selector switch or the regulating
range
selector set for the wrong applied line voltage
or if the wrong line fuse is used.
Line Voltage Selection
This instrument operates from either a 115-volt or a
230-volt nominal line voltage source, 48 to 440 hertz. To
convert 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 115-to-
230 volt adapter may be required
for the line-cord plug. Be
sure to use the
correct line fuse for the line voltage
selected (see Table 1).
Regulating Range Selection
The Regulating Range Selector assembly (located on
the rear panel) is set
for one of the line voltage ranges
shown in Table 1. Italso contains the linefuse for overload
protection.
To change the regulating range:
1. Disconnect the instrument from 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. 1 ).
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.
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Fig. 1. Regulating range selector & line fuse.
TABLE 1
Regulating Ranges
Regulating Range
Range Selector 115-Volts 230-Volts
Switch Position Nominal Nominal
LO (Switch bar in 99 to
121 volts
198 to 242 volts
lower holes)
M (Switch bar in 104 to 126
volts 207 to 253 volts
middle holes)
HI (Switch bar in 108 to 132
volts 216 to 264 volts
upper holes)
Fuse Size 1.5 A
3AG 0.75 A 3AG
Fast-blow Fast-blow
OPTIONS
Options are available to alter oscilloscope performance
to meet particular applications . A number in either M OD
slot (see Item 60, C ontrol s, Connectors , and Indi cator s)
indicates a
modified oscilloscope .
466/464
DM44 Operators 3

CONTROLS, CONNECTORS AND INDICATORS
VERTICAL
1. CH 1 and CH 2 VOLTS/DIV-Selects the vertical
deflection factor ina 1-2-5sequence (VAR control must be
in
the calibrated detent for the indicated deflection factor).
2. VOL TS/DIV Readout-Consists of two small lamps
for each channel, located beneath the skirt of each
VOL
TS/DIV knob. One or the other lamp will light up to
indicate the correct deflection factor 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
VOL
TS/DIV switch, and extends the maximum vertical
deflection to at least 12.5 volts per division (5 volt
position).
4.
UNCAL Lamp-Indicates when the VAR
VOL TS/DIV control is out of the calibrated detent and the
vertical
deflection factor is uncalibrated.
5. POSITION-Positions the display vertically. In the
X-Y mode, the CH 2 POSITION
control positions on the Y
axis (vertically) and the
Horizontal POSITION control
positions on the X-axis (horizontally).
Fig. 2. Vertical controls, connectors, and indicators.
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6. CH 1 OR X and CH 2 OR Y-lnput connectors for
application of external signals to the inputs of the vertical
amplifier. In the X-Y mode of operation, the signal
connected to the CH 1 OR X connector provides horizon-
tal deflection and the signal connected to the CH 2 OR Y
connector provides vertical deflection.
7. AC-GND-DC-Selects the method used to couple a
signal
to the input of the vertical amplifier. In the AC
position, signals are capacitively coupled to the vertical
amplifier. The de component of the input signal is blocked.
In
the GND position, the input of the vertical amplifier is
disconnected from the input connector and grounded to
allow the input coupling capacitor to precharge. In the DC
position, all components of the input signal are passed to
the input amplifier.
8. VERT MODE-Selects mode of operation for ver-
tical
amplifier system.
CH
1: Channel 1 only is displayed.
ALT: Provides dual-trace display
of thesignals of both
channels. Display
is switched between channels at the end
of each sweep. Useful at sweep rates faster than about 50
microseconds/division.
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 INVERTswitch in Channel
2 allows the display to be CH 1 plus CH 2
or CH 1 minus
CH 2. Useful for common-mode rejection to remove an
undesired signal or for de offset.
CHOP: Provides dual-trace
display of the signals of
both channels. Display is switched between channels at a
repetition rate
of approximately 250 kHz. Useful at sweep
rates slower than about 50
microseconds/division, or
when a dual-trace, single-sweep display is required.
CH
2: Channel 2 only is displayed. It must be selected
in X-Y operation.
9. 20 MHz BW/TRIG VIEW-Dual-purpose switch that
limits the bandwidth of the vertical amplifier system to
approximately 20 MHz when pulled, or when pressed,
causes the signal applied to A
Trigger Generator to be
displayed on the crt.
10.
INVERT-Channel 2 display is inverted in the
INVERT (button in) position.
@ 466/464 DM44 Operators 5
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DISPLAY AND STORAGE
Fig. 3. Display and storage controls, connectors, and indicators.
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11a. Internal Graticule-Eliminates parallax. Risetime,
amplitude and measurement points are indicated at the
left-hand graticule edge.
11b. Reduced Scan Graticule (466
Only)-When
operating in the reduced scan mode thedeflectionfactors,
set
by the VOL TS/DIV and TIME/DIV switches, are
referenced
to the smaller divisions of this graticule. All
measurements should be made
within this graticule when
operating in the reduced scan mode.
12.
BEAM FINDER-Compresses the display to within
the graticule area independently of display position or
applied signals and provides a visible viewing level.
13. INTEN-Controls brightness of the crt display.
14.
FOCUS-Adjusts for optimum display definition.
15. SCALE ILLUM-Controls graticule illumination.
16. ASTIG-Used in conjunction with the FOCUS
control to obtain awell-defined display. Itdoes not require
readjustment in normal use.
17.
TRACE ROTATION-Adjusts trace to align with
the horizontal graticule lines.
18. REDUCED SCAN
(PULL -INTEN knob)-
Reduces display to the small reduced scan graticule with
an increase in
writing rate. 466 only.
19. REDUCED SCAN LAMP-Indicates that the
reduced scan mode
is in operation. 466 only.
20. STORAGE
LEVEL-Varies the writing rate of the
crt in the FAST and VAR PERS storage modes.
21. SAVE-Provides longer viewing time. It prevents
accidental erasure
of the stored display.
22. SAVE
INTEN-Varies the intensity of the SAVE
mode.
23. NON STORE-Allows operation of the instrument
as a conventional oscilloscope in the NON STORE mode.
24. VAR
PERS-Permits variable retention of. the
stored display.
25. FAST-Used for fast-writing displays. FAST mode
disables the TRIG MODE switch. It automatically se-
quences
an erase cycle, unless the VIEW TIME control is
in the full clockwise detent (manual). Itwaits atime period
determined by the VIEW TIME
control; then resets the
sweep in a single-sweep mode.
26. VIEW
TIME-Varies the retention time (per-
sistence)
of the stored display in the VAR PERS mode. It
varies the time between erase cycles in FAST mode.
27. ERASE-Erases the stored display, except in
SAVE mode when ERASE
is disabled.
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Fig. 4. DM44 controls, connectors, and indicators.
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DM44
28. Input Connectors- Two banana jacks provide +
(red) and COM (black) inputs for voltage and resistance
only.
29.
Probe Connector-Input connector for the
temperature probe.
30.
Readout-Negative polarity indication is auto-
matic for negative de voltage and temperature with no
polarity indication for positive measurement. A blinking
display indicatesoverrange. Thedecimal point is position-
ed by the FUNCTION and RANGE controls for multimeter
operation and by the oscilloscope A TIME/DIV switch in
the TIME or 1/TIME modes.
31.
RANGE-Selects from .2 V to 1.2 kV de in 5ranges
(1200 volts is the maximum safe
input in the 1.2 kV de
mode);
from 200 ohms to 20 megohms in 6 ranges.
32.
FUNCTION-Selects VOLTS, OHMS, TEMP (° C),
1/TIME, or TIME functions of the DM44.
33. Scale Factor
Lamps- Two lamps.
In
the TIME function, the Readout and Scale Factor
Lamps indicate the time difference between the two
intensified zones on the crt display. One lamp or the other
will light to indicate ms or µs. No lamp lit indicates
seconds.
In the 1/TIME function the Readout and Scale Factor
Lamps indicate the number
of measured intervals per unit
of time. One lamp or the otherwill light to indicate intervals
per
ms (1/ms lamp) or intervals per µs (1/µs lamp). No
lamp lit indicates intervals per second. If the duration
of
one event is being measured, the Readout and Scale
Factor Lamps indicate frequency. The
1/ms lamp in-
dicates kHz, the 1/µs lamp indicates MHz, and
no lamp lit
indicates Hz.
34. ll.
TIME-Used in conjunction with the DELAY
TIME POSITION control in the TIME and 1/TIME func-
tions. The ll. TIME control moves only the time-
measurement point. The DELAY
TIME POSITION control
moves both the reference point and the time-
measurement point. With the time-measurement
point to
the left of the reference point the Readout indicates a
negative time difference.
NOTE
You can modify your instrument to make the DELAY
TIME POSITION
control move only the reference
point.
The procedure for making this modification is
located in the Maintenance section
of the DM44
Service manual.
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Fig. 5. Trigger controls, connectors, and indicators.
TRIGGER I
35. TRIG MODE-Determines the mode of trigger
operation for A Sweep. I
AUTO: Sweep is initiated by theapplied trigger signal.
In 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.
NORM: Sweep
is initiated bytheapplied trigger signal.
In 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 pushbutton is pushed, the A
Sweep operates in the single sweep mode.
After a single
sweep
is displayed, further sweeps cannot be presented
until the SINGL SWP button is again pushed. It is useful
when the signal to
be displayed is not repetitive or varies in
amplitude, shape
or time causing an unstable conven-
tional display. It can also
be used to photograph a
nonrepetitive signal.
36. READY
Lamp-Indicates A Sweep is "armed" and,
upon receipt
of an adequate trigger signal, will present a
single-sweep display.
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37. TRIG Lamp-Indicates that A Sweep is triggered
and will produce a stable display. It is useful for setting up
the trigger circuits when a trigger signal is available
without a display on the crt (for example, when using
external triggers).
38. A
TRIG HOLDOFF-Provides continuous control
of time between sweeps. Allows triggering on aperiodic
signals (such as complex digital words). In the fully
clockwise position (BENDS A), A sweep is reset at the end
of B sweep to providethe fastest possiblesweep repetition
rate
for delayed-sweep presentations and low-repetition
rate signals. Use the A trigger controls for the best
possible display before using the A TRIG HOLDOFF
control.
39. COUPLING-Determines method used to couple
signals to the trigger generator circuit.
AC: Signalsare capacitively coupled to the input of the
trigger generator. De is rejected and signals below about
30 Hz are attenuated.
LF REJ: Signals are capacitively coupled
to the input
of the trigger circuit. De is rejected and signals below
about 50 kHz are attenuated. It is useful for providing a
stable
display of the high-frequency components of a
complex waveform.
HF
REJ: Signals are capacitively coupled to the input
of the trigger circuit. De is rejected and signals below
about 30 Hz and above about 50 kHz are attenuated. It 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
of the trigger circuit. It is useful for providing a
stable display
of low-frequency or low-repetition rate
signals, except the
combination of the ALT (dual trace)
mode with the trigger SOURCE switch in NORM.
40.
SLOPE-Selects the slope of the trigger signal that
starts the sweep.
+: Sweep can be triggered from the positive-going
portion of a trigger signal.
-: Sweep can be triggered from the negative-going
portion of a trigger signal.
Correct SLOPE setting
is important in obtaining a
displaywhen
only a portion of a cycle is being displayed.
41.
LEVEL-Selects the amplitude point on the trigger
signal at which the sweep is triggered. It is usually
adjusted
for the desired display after trigger SOURCE,
COUPLING and SLOPE have been selected.
@ 466/464 DM44 Operators
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