Tektronix 5103N Instruction Manual
INSTRUCTION
MANUAL
S103N
OSCILLOSCOPE
SYSTEM
pLO^j/sl
SBCTIDI4
Tektronix
,
Inc.
•
P.
O.
Box 500
•
Beaverton, Oregon 97005
•
Phone
644-0161 •
Cables:
Tektronix
070
-
1143-00
471
m.
:
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+*
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.
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*'"
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ii
!
|t»i
t
fU'lUd
ith all
requests
for
parts
or
pacifications and
price
change
privileges
reserved.
Copyright
©
1971
by
Tektronix,
Inc.,
Beaverton,
Oregon.
Printed
in the
United
States
of
America.
All
rights
reserved.
Contents
of
this
publication
may
not
be
reproduced
in
any
form
without
permission
of
the
copyright
owner.
«St 4.3
‘ivXP-
U.S.A.
and foreign
Tektronix
products
covered
by
U.S.
and foreign
patents
and/or
patents
pending.
5103N
TABLE OF
CONTENTS
SECTION 1
SPECIFICATION
Introduction
Instrument
Options
Table
1-1
Electrical
Characteristics
Table
1-2
Environmental
Characteristics
Table
1-3
Mainframe
Physical Data
Page
1-1
1-1
1-1
1-2
1-3
SECTION 2
OPERATING
INSTRUCTIONS
General
2-1
Preliminary
Information
2-1
Rackmounting
2-1
Operating
Voltage
2-1
Operating
Temperature
2-2
Plug-In Units
2-2
Installation
2-3
Selection
2-3
General
Operating
Information
2-3
Display
Switching
Logic
2-3
Vertical
Display
Mode
2-4
X-Y
Operation
2-4
Raster
Display
2-4
Basic
Oscilloscope
Applications
2-4
General
2-4
Peak-to-Peak
Voltage
Measurements—AC
2-5
Instantaneous
Voltage
Measurements—DC
2-5
Comparison
Measurements
2-6
Time
Period
Measurement
2-7
Determining
Frequency
2-8
Risetime
Measurements
2-9
Multi-Trace
Phase
Difference
Measurement
2-10
X-Y
Phase
Measurements
2-11
SECTION 3
CIRCUIT
DESCRIPTION
Page
Replacement
Parts
4-5
Standard
Parts
4-5
Special Parts
4-5
Ordering
Parts
4-5
Component
Replacement
4-5
General
4-5
Circuit Board
Replacement
4-5
Transistor and
Integrated Circuit
Replacement
4-6
Interconnecting
Pin Replacement
4-6
Switch
Replacement
4-6
Cathode-Ray
Tube
Replacement
4-7
Neon Bulb
Replacement
4-8
Power
Transformer Replacement
4-8
Fuse
Replacement
4-8
Recalibration After
Repair
4-8
SECTION 5
CALIBRATION
Introduction
5-1
Services
Available
5-1
Equipment
Required
5-1
Preliminary
Procedure
5-1
Procedure
5-2
SECTION 6
RACKMOUNTING
Introduction
6-1
Instrument
Conversion
6-1
Mounting
Method
6-1
Rack
Dimensions
6-1
Installing
the
Slide-Out
Tracks
6-1
R5100
Installation and
Adjustment
6-4
Maintenance
6-4
Block
Diagram
Description
3-1
Interface
3-1
Clock
Generator
3-1
Countdown
Circuit
3-1
Auxiliary
Boards
3-2
Vertical
Amplifier
3-2
Horizontal
Amplifier
3-2
Power Supply
3-2
Power
Input
3-2
Low-Voltage
Rectifiers
and Unregulated
Outputs
3-2
Line
Trigger
3-3
CRT
Heater
Windings
3-3
Calibrator
3-3
SECTION
7
ELECTRICAL
PARTS
LIST
Abbreviations
and Symbols
Parts Ordering
Information
Index
of
Electrical
Parts
List
Electrical
Parts List
SECTION 8
DIAGRAMS
and CIRCUIT
BOARD
ILLUSTRATIONS
Symbols
and
Reference
Designators
Schematic
Diagrams
and
Component
Board
Locations
SECTION 9
MECHANICAL
PARTS
LIST
SECTION
4 SYSTEM
MAINTENANCE
5100
Panel
Removal
4-1
Preventive
Maintenance
4-1
General
3-1
Cleaning
4-1
Calibration
4-1
Troubleshooting
4-1
General
4-1
Troubleshooting
Aids
4-1
Troubleshooting
Equipment
4-3
Troubleshooting
Techniques
4-3
Mechanical
Parts
List
Mechanical
Parts
List
Illustration
Accessories
Repackaging
CHANGE
INFORMATION
Abbreviations
and
symbols
used
in this
manual
are based
on
or
taken
directly
from
IEEE
Standard
260
"Standard
Symbols
for
Units",
MIL-STD-12B
and
other
standards
of the
electronics
industry.
Change
information,
if any,
is located
at
the rear
of
this
manual.
SECTION
1
SPECIF1CATION
5103N
Change
information,
if any,
affecting
this section will be found
at
the rear of the manual.
Introduction
,
NOTE
The 5103N
Power
Supply/Amplifier
module is an inter-
connection unit
for the display
module and
plug-in units. It
is operated
with
a
display
module, and
comprises one-half
of the
5100-series
oscilloscope
mainframe. It
accepts
up
to
three plug-in
units and
provides
pre-amplification
for the
deflection signals.
The
center and
left plug-in
compartments
are connected
to the
vertical
deflection system,
and the
right plug-in
compartment
is
connected to the
horizontal
deflection system.
Electronic
switching between
the left
and
center plug-ins
allow a
multi-trace
vertical
display
(chopped and
alternate
time-sharing modes).
The unit also
contains
regulated
DC-voltage
supplies to
provide power to
the
instrument
system.
The following electrical characteristics
apply over
an
ambient
temperature range of
0°C
to
+50°C.
Many of
the
measurement
capabilities
of the
5100-
Series
Oscilloscope
are
determined by
the
choice of
display
modules
and plug-in
units.
The
following
electrical
characteristics
apply
to the
Power
Supply/
Amplifier
unit only,
unless
noted
otherwise.
For
display
modules
or plug-ins
only,
see the
specification
section
of the
manual for
that unit.
INSTRUMENT
OPTIONS
Option 1
An export
transformer
is
available for
the 5100-series
oscilloscopes, and can be installed
as
part
of
the instrument
when ordered, or it can be
installed
at
a
later time. This
transformer permits
operation from
100-volt,
110-volt,
120-volt, 200-volt, 220-volt, and 240-volt sources
with
power-line frequencies
of from
50 to 60
hertz
and 400
hertz. For further information on option
1,
see
your Tek-
tronix, Inc.,
catalog,
or
contact
your local Tektronix Field
Office or representative.
TABLE
1-1
ELECTRICAL CHARACTERISTICS
Characteristic
Performance Requirement Supplemental Information
Vertical and
Horizontal Amplifiers
Input Signal
Amplitude
(Differential Input)
50
millivolts per
displayed division, ver-
tical
and
horizontal.
Horizontal
Centering 0.5
division or less.
Bandwidth DC to
at least 2.5
megahertz.
X-Y Phase Difference
(Checked
with two plug-ins
of the
same type)
1°
or less to 100 kilohertz.
Sensitivity
Change
Accuracy
degrades
by up to
1% when
operated in split-screen storage.
1-1
Specification—
5 103N
TABLE
1-1
(cont)
Characteristic
Performance
Requirement
Supplemental
Information
Channel Switching
Chop Clock Frequency
About 200 kilohertz.
Channel Chop Rate
About 100 kilohertz.
Plug-In
Chop Rate
About 50 kilohertz.
Alternate Frequency
Sweep rate (once
each sweep).
Plug-In
Alternate Rate
•
One-half sweep
rate (once
every two
sweeps).
Channel Alternate Rate
One-fourth
sweep
rate (once
every four
sweeps).
TABLE
1-2
ENVIRONMENTAL
CHARACTERISTICS
Characteristic
Performance
Temperature
Operating
Range
0°C to
+50° C.
Non-operating
Range
-40°
C to +70°C.
Altitude
Operating
Range
To 1
5,000
feet.
Non-operating
Range
To
50,000
feet.
Vibration
Range
To 0.01 5 inch
peak-to-peak
displacement
at 50 cycles per
second.
Shock Range
To
30
g's, 1/2 sine,
1 1 milliseconds
duration.
Specification
—5
1
03N
TABLE
1-3
MAINFRAME PHYSICAL
DATA
(5103N with a Display Unit)
Characteristic
5100-Series Oscilloscope
R51 00-Series Oscilloscope
Dimensions (maximum)
Height
(overall) 1
1
.6
in.
(29.5 cm)
5.2
in.
(13.2 cm)
(cabinet) 1 0.5
in.
(26.7
cm)
Length (overall) 1 9.9
in.
(50.5
cm)
20.0 in.
(51.0
cm)
(cabinet)
1 8.3 in.
(46.5
cm)
18.3
in.
(46.5
cm)
Width (overall)
8.4 in.
(21.4 cm)
19.0
in.
(48.3
cm)
(cabinet)
16.8
in.
(42.7
cm)
Net Weight
«22.8
lbs.
(10.3
kg) ^23.5
lbs.
(10.7
kg)
Shipping
Weight
«30.0
lbs.
(13.6
kg) «39.0 lbs.
(17.7
kg)
Export
Weight
^45.0
lbs. (20.4
kg) ^59.0 lbs.
(26.8
kg)
1-3
NOTES
5103N
SECTION 2
OPERATING
INSTRUCTIONS
Change
information, if
any, affecting
this section
will
be found at
the
rear
of this
manual.
General
To
effectively
use
the 5103N,
the operation and capa-
bilities
of the
instrument
must
be known. The 5103N
Power
Supply/Amplifier
module
forms the basis
of
an
oscil-
loscope
system,
and
requires a
display
module and plug-ins
to
complete
the system.
This
section
describes inter-
connection
and
general
operation
of
the
units, including
preliminary
information
for first-time
turn-on,
selection
and
installation
of plug-ins,
general operating
information,
and some
basic
oscilloscope
applications.
Detailed
operating
information
for
a
specific
display
module or
plug-in is
given
in the
instruction
manual for that
unit.
PRELIMINARY
INFORMATION
Rackmounting
The
5103N
Power
Supply/Amplifier
module and
the dis-
play
module
can
be
fastened
together
stacked
or
side by
side,
permitting
operation
as a
bench
oscilloscope,
or it
can
be
operated
in a
standard
19-inch rack.
Complete
instruc-
tions
for
rackmounting
are
given
in Section
6,
Rack-
mounting.
NOTE
Before
attempting
to
operate
the
instrument,
make
sure
the
module
wiring
interconnections
are correct,
and
if
display
modules
have
been
changed,
that the
correct
auxiliary
board is
installed in
the
socket
on
the
plug-in
interface
board.
Operating
Voltage
This
instrument
is
designed
for operation
from a
power
source
with
its
neutral at
or near
earth
(ground)
potential
with a
separate
safety-earth
con-
ductor.
It is
not
intended
for
operation
from
two
phases
of
a
multi-phase
system,
or across
the legs
of
a
single-phase,
three-wire system.
The
5100-Series
Oscilloscope
is
operated
from a
1
15-volt
nominal
line
voltage
source (NOTE:
for
instrumentshaving
optional
export
transformer,
see
information
following
Table
2-1
).
The
power
transformer is wired
to
permit
either
of two
regulating
ranges to
be selected.
The range
for
which
the
primary taps
are set is
marked on the
rear panel
of the
instrument.
Use
the
following
procedure to
change regu-
lating
ranges:
1
.
Disconnect
the
instrument
from the
power source.
2.
Remove the
bottom
dust
cover
of the
instrument
to
gain access to
the
Power Supply
circuit board
.
3.
Remove the
brown
line-selector
block
from the
square-pin
connectors
(see Fig. 2-1)
and
place it
on
the
desired set
of pins
(use pins
marked H
or M
only).
Select a
range
which is
centered
about
the average
line
voltage
to
which
the
instrument is
to be
connected
(see Table
2-1
).
4.
Change
the
nominal
line
voltage
information
on
the
rear
panel of the
instrument. Use a
non-abrasive
eraser
to
remove
previous
data,
and
mark in
new data
with a
pencil.
5.
Replace
the
bottom
dust
cover and
apply
power to
the
instrument.
TABLE
2-1
Regulating
Ranges
Line
Selector
Block
Position
Regulating
Ranges
L Do
not
use
Internally
disconnected
M
(110
V
Nominal)
99
VAC
to 121
VAC
H
(120
V
Nominal)
108
VAC
to
132 VAC
Optional
Export
Transformer.
An
optional
export
trans-
former
permits
the
5100-Series
Oscilloscope
to be
operated
from
either a
115-volt
or
a
230-volt
nominal
line
voltage
source.
This
transformer is
wired to
permit
one
of
three
regulating
ranges
to
be
selected
for
either
115-volt
or
230-volt
nominal
operation.
The
range
for
which
the
2-1
Operating
Instructions—
5103N
Fig.
2-1.
Location
of
the
line-selector
block
on the Power Supply
circuit
board.
primary taps
are set is
marked
on
the
rear panel of
the
instrument. Use
the
following
procedure to obtain correct
instrument operation
from the line voltage
available:
5. Change the nominal line
voltage
information
on the
rear
panel of the instrument.
Use a
non-abrasive
eraser
to
remove
the previous
data, and mark in
new
data with
a
pencil.
6.
Replace the
bottom dust cover and
apply power
to
the instrument.
Damage to the instrument
may result from
incorrect
placement of
the line-selector block.
TABLE
2-2
Regulating
Ranges For Export
Transformer
Line
Selector
Block
Position
Regulatir
1
15-Volts
Nominal
lg
Range
230-Volts
Nominal
L
90 VAC
to 110
VAC
180
VAC to
220
VAC
M
99 VAC
to 121
VAC 198
VAC
to 242
VAC
H
108 VAC
to
132 VAC
216
VAC to
264
VAC
Line Fuse
Data
1
.6 A
slow
-blow
1
A slow-blow
1
. Disconnect the instrument from
the
power
source.
2.
Remove the
bottom dust cover of
the instrument
to
gain
access to the Power
Supply circuit board.
3.
To convert from
115 volts to
230 volts
nominal line
voltage, or
vice versa, remove
the line-selector
block from
the square-pin
connectors (see Fig.
2-1) and
replace
it with
the
other
block. Remove the line
fuse from
the fuse
holder
located
on the rear
panel
of
the display
module and
replace
it with
one having
the correct rating.
The
unused line-
selector
block and line fuse
can be
stored on the Power
Supply circuit board.
Change the
line-cord
power
plug
to
match the
power-source
receptacle or
use an adapter.
NOTE
The
1 15-volt block
is color coded
brown,
and it con-
nects the transformer
primary windings
in parallel.
The
230-volt block is color
coded red,
and it
connects
the primary
windings in series.
4.
To
change regulating ranges,
place
the line-selector
block on the desired
set
of
square
pins. Select
a
range
which
is centered
about the average line
voltage
to which the
instrument
is to be connected (see
T
able 2-2)
.
Operating Temperature
The
5103N
can be operated where the ambient air
temperature
is
between
0°C
and
+50°C.
The instrument can
be stored in ambient temperature between
—
40°C
and
+70°C.
After storage
at a
temperature
beyond the
operating
limits, allow
the
chassis temperature
to
come within the
operating limits before power is
applied.
A thermal cutout in
the display module provides thermal
protection and disconnects
the power
to
the instrument if
the internal temperature exceeds a
safe
operating level. This
device will automatically re-apply
power
when the tempera-
ture
returns
to a
safe level.
PLUG-IN UNITS
General
The 5103N is designed to accept up to three Tektronix
5-series
plug-in units. This plug-in
feature
allows
a
variety
of
display
combinations and also allows selection of band-
width,
sensitivity, display mode, etc., to
meet
the measure-
ment requirements. In addition, it allows
the
oscilloscope
system to be expanded to meet future measurement
requirements.
The overall capabilities of
the
resultant
system are in
large
part determined by the characteristics of
the
plug-ins selected.
2-2
Operating
Instructions—
51
03N
Installation
To
install
a
plug-in unit
into one
of
the plug-in compart-
ments,
align the slots in the
top and bottom
of
the plug-in
with the associated guides in
the plug-in compartment. Push
the plug-in unit
firmly
into
the plug-in
compartment
until it
locks into place.
To remove a
plug-in, pull the release
latch
on the plug-in
unit to disengage
it and pull the unitout of
the
plug-in compartment.
Plug-in units can be removed or
installed without turning
off the instrument power. It is not
necessary
that
all of the plug-in
compartments
be
filled
to
operate the instrument; the
only plug-ins needed are those
required for the measurement to
be made.
When the display unit is
calibrated in accordance with
the calibration procedure given
in the display
unit instruc-
tion manual, the
vertical and
horizontal
gain
are
standard-
ized.
This allows calibrated
plug-in units to be changed
from one plug-in
compartment to
another
without re-
calibration. However, the
basic calibration
of the
individual
plug-in units should be
checked when they
are installed
in
this system to
verify their
measurement accuracy.
See the
operating instructions section
of the plug-in unit manual
for
verification procedure.
Selection
The plug-in
versatility of the 5100-series oscilloscope
allows a
variety of display modes
with
many
different
plug-
ins.
The following
information
is
provided here
to aid
in
plug-in selection.
To produce
a single-trace display, install
a single-channel
vertical unit (or
dual-channel unit
set
for
single-channel
operation) in
either
of
the vertical
(left
or center)
compart-
ments and
a time-base unit in the horizontal (right)
com-
partment.
For dual-trace displays, either
install
a dual-
channel
vertical unit in one of the vertical
compartments or
install
a
single-channel vertical
unit in each vertical
com-
partment.
A combination of
a
single-channel
and
a
dual-
channel
vertical unit allows a three-trace display;
likewise,
a
combination of
two dual-channel vertical units allows
a
four-trace
display.
To
obtain a
vertical sweep
with the
input
signal
displayed
horizontally, insert the
time-base unit into one
of
the vertical
compartments and
the amplifier unit in the
horizontal compartment.
If
a
vertical sweep is used,
there
is
no retrace blanking;
however,
if used in
the right vertical
(center)
compartment,
internal triggering is
provided.
For X-Y
displays,
either
a
5A-series amplifier unit or a
5B-series time-base
unit
having an
amplifier channel can be
installed in the
horizontal
compartment
to accept
the
X
signal. The
Y
signal is
connected to a
5A-series amplifier
unit
installed in a
vertical compartment.
Special
purpose plug-in units may
have specific
restric-
tions regarding
the compartments
in which they can
be
installed.
This
information will be given in the
instruction
manuals
for these plug-ins.
GENERAL
OPERATING INFORMATION
Display
Switching Logic
General.
The electronic
switching for time-shared dis-
plays is produced at
the plug-in interface
within
the
main-
frame; however,
the switching logic
is
selected on the plug-
in
units. The system
allows any combination of plug-ins and
Display switch settings.
Refer
to
the individual plug-in
manuals
for specific capabilities and
operating procedures.
Vertical
Plug-in
Compartments.
When
a
vertical
plug-in
is in the
active mode
(Display button pushed in), a
logic
level is
applied
to
the switching
circuit in the
mainframe
and
a
display
from this plug-in will
occur. When two plug-
ins are both active
in the vertical
compartments,
a
multi-
trace
display will occur
(Alternate or Chopped). When no
plug-in is in
the active mode,
the signal from the
left
com-
partment
will be
displayed.
A
time-base unit operated in
one
of the vertical compartments
has
a
permanent internal
connection to apply a
logic level to the switching
circuit;
thus, a
vertical trace produced by this unit
will always be
displayed.
Horizontal Plug-in
Compartment. Alternate
or Chopped
display switching is selected
on
a
time-base
unit operated
in
the horizontal
compartment. When the
Display
switch is
out (Alt),
a negative impulse is supplied
at the
end
of
the
sweep to allow
alternate switching
between
plug-ins and
plug-in
channels. When the
Display
switch is pushed
in
(Chop),
a
chopped
display will appear if
a multi-trace
dis-
play
is required by the
plug-ins in the
vertical compart-
ments. An amplifier
plug-in unit
operated
in the
horizontal
compartment has
a permanent
internal
connection
to pro-
vide
a
chopped
display
if
it is
required.
Switching
Sequence. Four
display
time
slots are
pro-
vided
on a
time-sharing
basis.
When
two
vertical
plug-ins are
active,
each
receives
two
time
slots
and
the
switching
sequence is left,
left,
right,
right,
etc.
The
two time
slots
allotted
to each
plug-in
are
divided
between
amplifier
channels
in
a dual-trace
unit; if
two
dual-trace
plug-ins are
active,
then
the
switching
sequence is
left
Channel
1,
left
Channel
2,
right
Channel
1,
right
Channel
2,
etc. If
only
one
vertical
plug-in
is
active,
it receives
all
four
time slots.
The
switching
sequence
is the
same for
both
the
Alternate
and
Chopped
display
modes.
Operating
Instructions—
5103N
Vertical Display Mode
Display On. To
display a signal,
the Display button of
the applicable
vertical plug-in unit must be
pushed
in to
activate the unit.
If two plug-ins are installed in the vertical
compartments and
only the
signal from one
of
the units
is
wanted, set the
Display
switch of the unwanted unit to
Off
(button out).
If
neither plug-in is activated, the signal
from
the
left
unit
will be
displayed. Both plug-ins can be acti-
vated
for multi-trace
displays.
Alternate
Mode.
The
alternate
position
of the time-base
unit
Display
switch
produces a
display which alternates be-
tween activated
plug-ins and
amplifier channels with each
sweep
of
the CRT.
The
switching sequence
is described
under Display
Switching
Logic in
this section. Although the
Alternate mode
can be used at
all sweep rates,
the
Chop
mode
provides a
more
satisfactory display at
sweep rates
from about
one
millisecond/division to
five
seconds/
division. At
these
slower sweep
rates, alternate-mode
switching becomes
difficult to
view.
Chopped Mode. The Chop position of the
time-base
unit Display switch produces
a
display which
is
electronically switched between channels
at a 200-kilohertz
rate. The switching sequence has been
discussed earlier.
In
general, the Chop mode provides the
best display
at
sweep
rates slower
than about one millisecond/division or
when-
ever dual-trace, single-shot phenomena
are to be displayed.
At
faster
sweep rates, the chopped switching
becomes
apparent
and may
interfere
with the display.
Dual-Sweep Displays.
When
a
dual-sweep time-base unit
is operated in the horizontal compartment, the alternate
and chopped time-shared
switching for either
the A or
B
sweep
is
identical to that
for
a single time-base unit. How-
ever, if
both
the
A
and
B
sweeps
are operating, the
5103N
operates in the independent
pairs
mode.
Under
this condi-
tion, the left vertical unit is
always
displayed at the
sweep
rate of the
A
time base and the right vertical unit
is dis-
played
at the
sweep rate
of
the
B
time base
(non-delayed
sweep
only). This
results in two displays that have com-
pletely
independent
vertical deflection and
chopped or
alternate sweep switching.
Dual-Beam Displays. When
a dual-beam display
module
is
operated with
the 5103N, the
switching
sequence
is
altered
slightly.
Between-channel
switching
occurs; how-
ever, switching
between
plug-ins is
not necessary
and does
not
occur. Also,
the
left
vertical
unit is always
displayed
by
the
upper
CRT beam and the right
vertical
unit is displayed
by the lower
CRT beam.
X-Y
Operation
In some
applications, it is desirable
to display
one signal
versus another
(X-Y) rather than
against an internal
sweep.
The
flexibility of
the plug-in units
available for
use with the
5103N
provides
a means
for
applying
a signal
to
the hori-
zontal
deflection
system
for
this type of
display. Some of
the
5B-series time-base
units can
be operated
as
amplifiers
in addition
to their normal
use
as
time-base
generators, or
an
amplifier
unit can be installed
in the horizontal
compart-
ment.
The latter
method
provides the
best X-Y
display,
particularly
if
two identical
amplifier
units are
used, since
both
the X and Y
input
systems will
have the
same capa-
bilities
and
characteristics.
In either
case, the mainframe
bandwidth
and
sensitivity are
equal
and inherent
phase shift
is adjustable
to 0 degrees in the
display
module. For
further
information
on obtaining
X-Y displays,
see
the plug-in
unit
manuals.
Raster
Display
A raster-type
display can be used
to
effectively
increase
the apparent sweep
length. For this
type
of
display, the
trace
is deflected both vertically
and horizontally
by
saw-
tooth signals, and is accomplished
by installing
a
5B-series
time-base
unit in one
of
the vertical
compartments as well
as one in the horizontal
compartment. Normally, the
unit
in the vertical
compartment should
be set to
a
slower sweep
rate
than
the one in the horizontal
compartment; the num-
ber of
horizontal
traces in the raster
depends upon the ratio
between
the two sweep
rates. Information
can be displayed
on the raster
using the Ext Intensity Input to provide
intensity
modulation of the
display. This type
of raster
display could
be used to provide
a
television-type display.
Complete information
on
operation
using the Z-axis feature
is
given in the operating instructions
section
of the display
module manuals.
BASIC
OSCILLOSCOPE
APPLICATIONS
General
The
5100-Series
Oscilloscope
and
its
associated
plug-in
units
provide
a very
flexible
measurement
system.
The
capabilities
of
the
overall
system
depend
mainly
upon the
plug-ins
that are
chosen for
use with
this
instrument.
The
following
information
describes
the
procedures
and
tech-
niques
for
making
basic
measurements.
These
applications
are not
described
in
detail,
since
each
application
must
be
adapted
to the
requirements
of the
individual
measurement.
Specific
applications
for
the
individual
plug-in
units are
described
in the
manuals for
those
units.
The overall
system
can also
be
used
for
many
applications
which
are
not
described
in
detail
either in
this
manual
or
in the
manuals
for
the
individual
plug-in
units.
Contact
your local
Tek-
tronix
Field
Office
or
representative
in making
specific
measurements
with
this instrument.
Operating
Instructions—
5103N
The
following books describe oscilloscope measurement
techniques
which can be
adapted for
use
with
this
instrument.
Harley Carter, "An
Introduction
to
the
Cathode Ray
Oscilloscope”,
Philips
Technical
Library, Cleaver-Hume
Press
Ltd., London, 1960.
J.
Czech, "Oscilloscope Measuring
Techniques",
Philips
Technical Library, Springer-Verlag, New York,
1965.
Robert
G.
Middleton,
"Scope Waveform
Analysis”,
Howard
W. Sams
&
Co. Inc., The
Bobbs-Merrill
Company
Inc.,
Indianapolis,
1963.
Robert
G.
Middleton
and L. Donald Payne,
"Using
the
Oscilloscope
in Industrial Electronics",
Howard
W.Sams&
Co. Inc.,
The Bobbs-Merrill Company
Inc.,
Indianapolis,
1961.
John
F. Rider and Seymour
D. Uslan, "Encyclopedia
of
Cathode-Ray
Oscilloscopes and Their
Uses", John F.
Rider
Publisher Inc., New York,
1959.
John F. Rider, "Obtaining and Interpreting
Test
Scope
Traces", John
F.
Rider
Publisher Inc., New York,
1959.
Rufus P. Turner, "Practical
Oscilloscope
Handbook”,
Volumes
1 and
2,
John
F.
Rider Publisher
Inc., New York,
1964.
Peak-to-Peak Voltage Measurements—
AC
To make
peak-to-peak voltage
measurements,
use the
following
procedure:
1
.
Set
the Input Coupling on the vertical plug-in
unit to
GND and connect the signal to the input connector.
2.
Set
the Input Coupling to AC and set the Volts/Div
switch
to
display about 5 or
6
vertical divisions of
the
waveform. Check that the Variable Volts/Div control (red
knob)
is in the Cal
position.
3. Adjust
the time-base
triggering controls for
a stable
display
and set
the Seconds/Div
switch
to display several
cycles
of
the waveform.
4. Turn the
vertical Position control so the lower
portion of
the
waveform coincides
with
one
of
the graticule
lines below the center
horizontal line,
and the top
of
the
Position
to center
vertical
line
Fig.
2-2.
Measuring peak-to-peak voltage of
a
waveform.
waveform
is
in the
viewing area. Move the display
with the
horizontal Position
control so one
of
the
upper peaks is
aligned with the
center vertical reference line (see
Fig.
2-2).
5.
Measure the vertical deflection from peak to peak
(divisions)
.
NOTE
This technique
may
also be
used to
make measure-
ments
between
two points on
the waveform
,
rather
than
peak to
peak.
6.
Multiply the distance (in divisions)
measured
in step
5
by
the Volts/Div switch setting. Also
include the attenua-
tion factor of the probe, if applicable.
EXAMPLE:
Assume
a
peak-to-peak vertical deflection of
4.6
divisions and
a
Volts/Div switch
setting of 5 V.
Peak-to-peak
_
4.6
5
(Volts/Div_
23
volts (divisions)
setting) volts
NOTE
If an
attenuator probe not having
the capability to
change
the scale factor readout (Volts/Div)
is used,
multiply the right side of
the above
equation by the
attenuation factor.
Instantaneous Voltage
Measurement—
DC
To measure the
DC
level
at a given point on
a
waveform,
use the following
procedure:
2-5
Operating
Instructions—
51
03N
r
r
f
Vertical
distance
1
I
1
—
—
—
'
"
(A)
—
—
J
A
Reference
line
Fig.
2-3. Measuring
instantaneous DC
voltage with
respect to
a
reference
voltage.
1.
Set the
Input
Coupling
of the vertical
plug-in unit
to
GND and
position
the
trace to the bottom
line of the grati-
cule
(or other
selected
reference
line).
If the voltage to be
measured is
negative
with
respect to ground, position
the
trace to the
top
line
of the graticule. Do not move
the
vertical
Position
control
after this
reference has been estab-
lished.
6. Multiply
the distance
measured
in
step 4 by the
Volts/Div
switch setting.
Include the
attenuation
factor of
the probe, if
applicable
(see the
note following
the Peak-to-
Peak
Voltage
Measurement
example).
EXAMPLE:
Assume that
the vertical
distance
measured
is
4.6
divisions,
the polarity
is positive,
and
the Volts/Div
switch
setting
is 2
V.
Instantaneous
_ 4.6
^
2
-
+9.2
Voltage
(divisions) (Volts/Div)
volts
Comparison
Measurements
In
some
applications,
it
may
be necessary
to establish
a
set
of
deflection
factors other
than those
indicated
by the
Volts/Div or
Seconds/Div switches.
This
is useful for
com-
paring
signals to
a
reference
voltage
amplitude or
period. To
establish
a new set of
deflection
factors based
upon
a
specific reference
amplitude or period,
proceed
as
follows:
VERTICAL
DEFLECTION
FACTOR
1.
Apply
a
reference
signal of known
amplitude
to the
vertical
input
connector. Using the
Volts/Div
switch and
Variable
Volts/Div
control, adjust the
display for
an exact
number of
divisions.
Do not
move the Variable
Volts/Div
control after
obtaining the
desired deflection.
NOTE
To
measure
a
voltage level with respect to a voltage
other
than
ground,
make the following changes to
step 1: Set
the
Input Coupling
switch to
DC
and
apply the
reference
voltage to the input connector,
then
position the
trace to the
reference line.
2.
Connect
the
signal to
the input connector. Set the
Input
Coupling to
DC
(the ground reference can be checked
at
any time by
setting the
Input Coupling to GND).
3.
Set the
Volts/Div switch
to
display
about 5 or
6
verti-
cal divisions
of
the
waveform. Check
that the Variable
Volts/Div control
(red
knob) is in the Cal position.
Adjust
the time-base triggering
controls for
a stable display.
4.
Measure the distance in divisions between the ref-
erence line and the point on the
waveform
at which the
DC
level is to be
measured. For example,
in Fig.
2-3
the
measurement is made
between
the reference line
and point
A.
5.
Establish the polarity. The voltage is
positive
if
the
signal
is
applied
to the
+
input connector and the waveform
is above the reference line.
2.
Divide the amplitude of
the reference
signal (volts)
by the
product
of
the
deflection in
divisions (established
in
step
1)
and the
Volts/Div
switch
setting. This is the Deflec-
tion
Conversion
Factor.
Deflection
Conversion
=
Factor
reference signal amplitude (volts)
deflection (divisions X Volts/Div setting
3.
To determine the peak-to-peak amplitude
of
a signal
compared
to a
reference,
disconnect the
reference and
apply the
signal to the input
connector.
4.
Set the
Volts/Div switch to
a setting
that provides
sufficient deflection
to
make the measurement. Do not
readjust the Variable Volts/Div control.
5.
To establish
a
Modified Deflection Factor
at
any
setting of the Volts/Div switch, multiply the Volts/Div
switch
setting by
the Deflection Conversion Factor
established
in step 2.
Modified
Deflection
Factor
Volts/Div
setting
Deflection
Conversion
Factor
®
2-6
Operating
Instructions—
5103N
6.
Measure the vertical deflection in divisions
and deter-
mine the amplitude by the
following
formula:
Div switch
setting by the
Deflection
Conversion Factor
established in step 2.
Signal
Amplitude
Modified
Deflection X
Factor
deflection
(divisions)
Modified
Deflection
Factor
Second
s/Div
switch setting
Deflection
X Conversion
Factor
EXAMPLE:
Assume a
reference
signal
amplitude
of
30
volts,
a Volts/Div switch setting of
5 V
and
a
deflection
of
four
divisions. Substituting
these values
in the
Deflection
Conversion
Factor formula
(step
2):
30
V
(4)
(5
V)
1.5
6.
Measure the
horizontal
deflection in divisions
and
determine the
period by the
following formula:
Modified
horizontal
Period
=
Deflection
X deflection
Factor
(divisions)
Then, with
a Volts/Div switch setting of
2 V, the Modified
Deflection Factor
(step
5)
is:
(2
V)
(1.5)
=
3
volts/division
To determine the peak-to-peak
amplitude of an
applied
signal which produces
a
vertical
deflection of five
divisions
with
the above conditions,
use the Signal
Amplitude
formula
(step
6)
:
(3
V)
(5)
-
15 volts
SWEEP
RATE
1.
Apply a
reference
signal
of
known
frequency
to the
vertical
input connector. Using the
Seconds/Div
switch
and
Variable
Seconds/Div control,
adjust the display
so that
one
cycle of
the signal covers an exact number
of
horizontal
divisions.
Do
not change
the
Variable
Seconds/Div
control
after
obtaining
the
desired
deflection.
2. Divide the period
of
the reference
signal
(seconds)
by
the
product of the horizontal
deflection
in divisions
(estab-
lished
in step
1)
and the
setting
of
the
Seconds/Div
switch.
This is the
Deflection
Conversion
Factor.
Deflection reference signal
period (seconds)
Conversion
=
horizontal
Seconds/Div
Factor
deflection X
switch
(divisions)
setting
3. To determine the period of
an unknown
signal,
dis-
connect
the reference and apply the
unknown signal.
4. Set the
Seconds/Div switch to
a setting that
provides
sufficient horizontal deflection
to make
an accurate
meas-
urement.
Do not
readjust
the
Variable
Seconds/Div
control.
EXAMPLE: Assume a
reference signal
frequency of 455
hertz (period 2.2
milliseconds), a
Seconds/Div switch
setting
of
.2 ms,
and a
horizontal deflection of eight divi-
sions.
Substituting these
values in the Deflection
Conver-
sion
Factor
formula (step
2):
(8)
(0.2
ms)
Then,
with
a
Seconds/Div switch
setting of
50
jus, the Modi-
fied
Deflection
Factor (step
5)
is:
(50jus)
(1.375)
=
68.75
microseconds/division
To
determine the time period
of
an
applied signal
which
completes one
cycle in seven horizontal divisions, use
the
Period formula (step
6):
(68.75
jus)
(7)
-
481
microseconds
This product can
be converted to frequency by
taking the
reciprocal
of
the
period (see application on
Determining
Frequency).
Time Period
Measurement
To measure the
time (period) between two points
on
a
waveform, use the
following procedure:
1.
Connect
the signal to the vertical input
connector,
select either
AC
or
DC
input coupling, and set the
Volts/
Div
switch
to
display about four divisions
of
the
waveform.
2.
Set
the time-base triggering controls to
obtain
a
stable
display. Set the Seconds/Div
switch
to
the fastest
sweep
rate that will permit displaying one cycle
of the
waveform in less than eight divisions (some
non-linearity
may occur in the
first and last graticule divisions
of dis-
play).
Refer
to Fig.
2-4.
5.
To establish a
Modified
Deflection
Factor
at any
setting of
the Seconds/Div switch, multiply
the
Seconds/
3.
Adjust the
vertical
Position control
to move the
points between which
the time measurement
is made to the
2-7
Operating Instructions—
5103N
Fig.
2-4.
Measuring time
duration (period) between
points on
a
waveform.
Fig.
2-5.
Measuring risetime.
center horizontal line. Adjust the horizontal Position con-
trol
to center
the time-measurement
points
within the
cen-
ter eight divisions
of
the
graticule.
4. Measure
the
horizontal distance
between the time
measurement
points. Be sure
the Variable Seconds/Div con-
trol
is in the
Cal position.
5.
Multiply the
distance
measured in step 4 by the
setting
of the
Seconds/Div
switch.
EXAMPLE:
Assume
that the
horizontal distance
between the
time-measurement
points
is
five divisions and
the Seconds/Div
switch is set to .1
ms.
Using the
formula:
p
.
^
horizontal
distance
^
Seconds/Div
(divisions)
switch setting
=
(5)
(0.1
ms)
=
0.5 ms
The period is
0.5
millisecond.
Determining Frequency
The
time
measurement technique can also
be used
to
determine the frequency of
a
signal.
The frequency of
a
periodically recurrent signal is the reciprocal of
the time
duration
(period) of one cycle. Use the following
pro-
cedure:
1. Measure
the period of
one
cycle of
the waveform
as
described in the previous application.
2.
Take the reciprocal of
the
period
to determine
the
frequency.
EXAMPLE:
The frequency of
the signal shown
in Fig.
2-4,
which
has
a
period of
0.5 millisecond,
is:
1
1
Frequency
=
:
—- =
—
=
2 kilohertz
period
0.5
ms
Risetime
Measurements
Risetime
measurements employ
basically the
same tech-
niques
as
the
time-period
measurements. The main
differ-
ence
is the
points between
which the
measurement is made.
The following
procedure gives
the basic method
of
measuring risetime
between the 10%
and
90%
points
of the
waveform.
1
.
Connect
the signal to
the input connector.
2. Set
the Volts/Div
switch and Variable
Volts/Div con-
trol
to
produce a
display
an
exact number
of divisions in
amplitude.
3.
Center the display about the
center horizontal line
with the vertical
Position control.
4.
Set the time-base
triggering controls to obtain a
stable display.
Set the
Seconds/Div switch to the
fastest
sweep rate that will display less than eight divisions
be-
tween the
10% and
90%
points
on the waveform (see Fig.
2-5).
5.
Determine the
10% and
90%
points on the rising
por-
tion
of
the waveform. The figures given in Table
2-3
are for
10% up
from
the start
of
the
rising portion
and 10%
down
from
the topofthe rising
portion
(90%
point).
2-8
Operating Instructions—
51
03N
TABLE
2-3
Divisions of
display
10%
and 90%
points
Divisions
vertically
between
10%
and
90%
points
4
0.4
and
3.6
divisions 3.2
5
0.5 and 4.5
divisions 4.0
6
0.6
and 5.4
divisions 4.8
7
0.7 and 6.3
divisions 5.6
8
0.8
and 7.2
divisions 6.4
6.
Adjust the
horizontal Position
control to move the
10%
point
of the
waveform to
the second
vertical
line
of
the graticule.
For
example,
with
a
six-division
display, the
10%
point
would be 0.6
division
up
from
the start
of
the
rising portion.
Fig.
2-6.
Measuring
time difference
between
two pulses.
7.
Measure
the
horizontal
distance
between
the 10%
and
90%
points.
Be
sure
the
Variable
Seconds/Div
control is in
the
Cal
position.
8.
Multiply
the
distance
measured
in
step
7 by
the
setting
of the
Seconds/Div
switch.
EXAMPLE:
Assume
that
the
horizontal
distance
be-
tween the 10%
and
90%
points
is six
divisions
and
the
Seconds/Div
switch is
set
to
1
jus.
Using the
period
formula to
find risetime:
Risetime
_
horizontal
distance
Seconds/Div
period
(divisions)
setting
=
(6)
(Ijus)
=
0.6
microsecond
The risetime
is
0.6
microsecond.
Time
Difference
Measurements
When
used in
conjunction
with a calibrated
time-base
plug-in
unit, the
multi-trace
feature
of
the
5100-series oscil-
loscope
permits
measurement
of
time
difference
between
two or
more
separate
events. To
measure time
difference,
use
the following
procedure:
1.
Set
the
Input
Coupling
switches
of the
amplifier
channels to
either AC
or DC.
2.
Set
the Display
Mode
switch on
the time-base unit
to
either Chop
or Alt.
In
general, Chop is
more
suitable for
low-frequency
signals and
the Alt
position is
more suitable
for high-frequency
signals.
More
information on
deter-
mining the
mode is
given
under
Vertical Display
Mode in
this section.
3.
Set
the
Triggering
Mode switches
to
trigger
the dis-
play
on
Channel
1
(or
Left
Plug-in).
4.
Connect
the
reference
signal to
the
Channel 1
input
connector
and
the
comparison
signal to the
Channel 2
input
connector.
The
reference
signal
should
precede the
com-
parison
signal
in
time.
Use
coaxial
cables
or
probes
which
have
similar
time-delay
characteristics
to
connect
the
signal
to the
input
connectors.
5.
If
the
signals are
of
opposite
polarity, push the
Invert
button to
invert the Channel 2
display. (Signals may be
of
opposite
polarity due to
180°
phase
difference; if
so,
take
this
into
account in
the final calculation.)
6.
Set
the
Volts/Div switches to
produce about
four
divisions
of displayed
waveform.
7. Set
the time-base
triggering controls
for
a
stable dis-
play. Set the
Seconds/Div switch
for
a
sweep
rate
which
shows three
or more divisions
between the measurement
points,
if possible.
8.
Adjust
the vertical Position
controls
to
bring
the
measurement
points to the
center horizontal reference
line.
9.
Adjust
the
horizontal Position
control so the
Channel
1
waveform
(reference) crosses
the center
horizontal line at
a
vertical
graticule line.
10.
Measure the
horizontal distance
between the
two
measurement
points (see
Fig.
2-6).
2-9
Operating
Instructions—
51 03N
1
1 .
Multiply the measured distance
by the setting of
the
Seconds/Div switch.
EXAMPLE:
Assume
that
the
Seconds/Div
switch
is
set
to
50
jus
and the horizontal
distance
between
measurement
points is four
divisions.
Using the formula:
_
^
.
Seconds/Div
horizontal
distance
Time Delay
=
X
setting
(divisions)
=
(50
jus)
(4)
=
200
jus.
The time
delay is 200
microseconds,
i
Multi-Trace Phase Difference Measurement
Phase comparison between
two or
more signals of
the
same frequency can be made using a dual-trace plug-in
or
two single-trace plug-ins. This method
of
phase difference
measurement can be used up to the
frequency
limit of the
vertical
system.
To make the comparison,
use the
following
procedure:
1.
Set
the Input
Coupling switches of the amplifier
channels
to
either
AC
or
DC.
2.
Set the Display Mode switch on the time-base
unit
to
either Chop or
Alt. In
general. Chop
is
more
suitable for
low-frequency signals and the Alt position
is
more
suitable
for
high-frequency signals. More information
on deter-
mining
the mode is given under Vertical Display Mode
in
this section.
Fig. 2-7.
Measuring
phase difference.
7. Set the
time-base
triggering
controls
to
obtain
a
stable
display.
Set the
Seconds/Div
switch
to a sweep
rate
which
displays
about
one cycle of
the
waveform.
8. Move
the
waveforms
to the
center
of the
graticule
with
the
vertical Position
controls.
9.
Turn the
Variable Seconds/Div
control
until one
cycle of the reference
signal (Channel
1)
occupies exactly
eight
divisions
between the
second and tenth
vertical lines
of the
graticule
(see Fig. 2-7). Each
division of
the graticule
represents
45°
of
the
cycle
(360°
+
8 divisions
=
45°/
division).
The
sweep rate
can be stated
in terms of
degrees
as
45°/division.
3.
Set the
Triggering Mode switches
to trigger the
dis-
play on Channel
1
(or Left plug-in).
10.
Measure
the horizontal
difference
between
corres-
ponding
points on the
waveforms.
4.
Connect the
reference signal
to the Channel
1 input
connector
and the
comparison
signal to the Channel
2 input
connector.
The
reference signal should
precede the com-
parison signal in
time.
Use coaxial cables or
probes which
have similar time-delay characteristics to connect the
signals
to
the input connectors.
11.
Multiply
the
measured distance
(in
divisions) by
45 /division
(sweep rate)
to obtain
the
exact
amount
of
phase
difference.
EXAMPLE:
Assume a horizontal
difference of
0.6
divi-
sion with
a sweep rate of
45°/division
as shown
in Fig.
2-7.
Using the
formula:
5.
If
the
signals are of opposite polarity, push
the Invert
button
to
invert the Channel 2 display. (Signals
may be of
opposite polarity due to
180°
phase
difference; if
so, take
this into
account in the
final calculation.)
horizontal
Phase
Difference=
difference
X
(divisions)
sweep
rate
(degrees/
division)
6.
Set the Volts/Div
switches and the Variable
Volts/Div
controls
so
the displays are equal and about five
divisions in
amplitude.
=
(0.6)
(45°)
The
phase
difference
is
27°.
27°
2-10
Operating
Instructions—
5103N
Fig.
2-8.
High-resolution
phase-difference
measurement with in-
creased sweep rate.
High
Resolution
Phase
Measurements
More accurate
dual-trace
phase
measurements
can
be
made by
increasing
the
sweep
rate (without
changing the
Variable
Seconds/Div
control
setting). One
of the easiest
ways to
increase the
sweep
rate is
with the SWP MAG
(10X) button on
the
time-base
unit. The
magnified
sweep
rate is
automatically
indicated
by
the
knob-skirt scale-
factor
readout.
EXAMPLE:
If the
sweep
rate
were increased 10
times
with the
magnifier,
the
magnified
sweep rate
would be
45°/
division-^
10=
4.5°/division.
Fig.
2-8
shows the
same sig-
nals as
used in
Fig. 2-7,
but
with
the
SWP
MAG button
pushed in. With a
horizontal
difference
of
six
divisions, the
phase
difference is:
horizontal
magnified
Phase
Difference
=
difference
X sweep
rate
(divisions)
(degrees/division)
(6)
(4.5°)
=
27°
The phase
difference is
27°.
X-Y
Phase
Measurements
The
X-Y
phase
measurement
method can
also be used
to
measure the
phase
difference
between
two
signals
of the
same
frequency.
The
phase
angle is
determined
from the
Lissajous
pattern as
outlined
in
the
following
steps:
1.
Insert
an
amplifier
plug-in
unit into
one
of
the
verti-
cal
plug-in
compartments
and an
amplifier
of the
same
type
into the
horizontal
plug-in
compartment.
Fig.
2-9.
Phase
difference measurement from an X-Y
display.
2.
Connect a
signal to
the input
connector
of
each
plug-
in
and select the
desired input
coupling.
3.
Position
the display
to the
center
of
the
screen and
adjust
the Volts/Div
switches to
produce a
display six
divi-
sions
vertically
(Y) and six
divisions
horizontally (X).
4.
Center
the
display in relation to
the center
vertical
graticule line.
Measure the
distances A and
B
as
shown in
Fig.
2-9.
Distance
B
is
the vertical
measurement
between
the
two points
where the trace
crosses the center vertical
line. Distance A
is the
maximum vertical
amplitude
of the
display.
5.
Divide
B
by A
to
obtain the sine
of
the phase
angle
(T>)
between the
two signals. The
angle can then
be
obtained from a
trigonometric
table.
If
the display
appears
as a
diagonal
straight line, the
two signals
are either in
phase
(tilted upper
right to
lower
left),
or
180°
out
of
phase
(tilted
upper
left
to
lower right).
If the display is a
circle,
the
signals are
90°
out
of phase. Fig.
2-10
shows
the
Lissajous
displays produced
between
0°
and
360°.
Notice
that
above
180°
phase
shift, the
resultant display
is
the
same as at
some lower
angle.
EXAMPLE:
Assume a
display
as
shown
in Fig.
2-9
where A is
6
divisions and
B
is
0.4 division.
Using the
formula:
Sine
=
-
7
-
=
=
0.0660
A
6
From
the
trigonometric
tables
(or slide
rule):
$
=
arcsin 0.0660
=
3.78°
2-11
Fig.
2-10.
Phase of
a Lissajous display. (A)
0°
or
360°,
(B)
30°
or
330°,
(C)
90°
or 270°,
(D)
150°
or
210°,
and
(E)
180°.
2-12
SECTION
3
CIRCUIT
DESCRIPTION
5103N
Change
information,
if
any,
affecting this section will be found
at
the rear of this
manual.
Introduction
This section
of the
manual
contains an
electrical
description of the circuits in the 5103N Power
Supply/
Amplifier
unit, and
discusses their relationship
to the other
instruments comprising the Oscilloscope
System. An
overall
block diagram of the unit and
complete schematics
are
given on pullout pages
at
the back of this
manual.
BLOCK DIAGRAM
DESCRIPTION
Vertical signals
to be displayed on the
cathode-ray
tube
are applied
to the Interface circuit
from
both
vertical
plug-
in compartments. With single-beam
display units, the
Inter-
face circuit determines
whether the signal from
the left
and/or right vertical unit
is
displayed;
with dual-beam
units,
the
Interface circuit establishes the proper
routing
to asso-
ciate the left
vertical plug-in signal with the
upper
CRT
beam and right vertical plug-in
signal with the lower
CRT
beam. The Vertical Amplifier
circuit provides
intermediate
amplification between
the vertical plug-in
units and
the
deflection amplifiers
in the display unit.
Time-base and
external signals for horizontal display
on
the
CRT
are
connected to the
Interface
circuit
from
the
horizontal plug-in compartment. The
Horizontal
Amplifier
circuit provides
intermediate amplification between the
horizontal plug-in unit
and the
deflection amplifier
in the
display
unit.
Additionally, the
Interface circuit provides an
inter-
connection
of
logic
levels, time-base triggering signals,
display-related signals, and
power-supply voltages between
the plug-in units and the
display
unit.
The
Low-Voltage
Regulator
circuits provide the voltage
necessary
for operation
of
the
oscilloscope system. These
voltages are
connected to all circuits
within the instrument.
Also
included in
this circuit is the
Calibrator, which
pro-
duces
a
square-wave output
with accurate amplitude
at a
repetition rate
of twice the power-line frequency. This out-
put
signal is useful
for calibration and
probe compensation,
and is available at
the front
panel of the display unit.
INTERFACE
General
The Interface circuit provides
an
interconnection
of
signals, logic levels,
and power-supply
voltages between
plug-in
units and the oscilloscope
mainframe.
It incorpo-
rates
circuits that determine
the vertical
display
mode and
amplify the
vertical and horizontal
display
signals.
Func-
tions
of
interconnections
not
discussed
are labelled
on the
I nterface
diagram.
Clock
Generator
The Clock
Generator
stage
produces
a 200-kilohertz
timing
signal (clock) for
chopping
between
vertical
plug-ins
and amplifier
channels
within the
plug-ins.
This
circuit
consists of
Q620,
Q626,
and their
associated
passive com-
ponents,
which are
connected
as
a multivibrator.
When the
multivibrator
receives
a chop
actuate level
(+5 volts), it free
runs
at a 200-kilohertz
rate.
(The chop
actuate level is
routed
through
the
vertical
plug-ins
to the
time-base unit,
and
is present
at
contact
A20
of
J603 when
a
multi-trace
display
is required
and
the
time-base
Display
switch
is set to
Chop.)
The chop
actuate level
also
disables
Q630,
locking
out
alternate-drive
pulses.
The
Clock
Generator
has two
outputs;
one is
sent to the
Countdown
circuit
as
a
timing
signal, and
the other
is
sent to the
CRT circuit
in the
dis-
play
unit
to blank the
chop-switching
transients.
Countdown
Circuit
The
Countdown
produces the
display
switching
signal
for
both
the Alternate
and Chopped
switching
modes.
This
circuit
is composed of
U640
and its
discrete
passive compo-
nents, which are
connected
as a pair of
RS flip-flops.
Each
flip-flop
is
a divide-by-two
counter,
and the first
one drives
the
second. The Countdown
Circuit
is activated by
a
negative-going
transition,
which can
come from either the
Clock
Generator or
from the
time-base
plug-in unit
via
grounded-base
amplifier
Q630.
The
Clock
Generator input
results in
chopped-mode
vertical switching.
The
input
from
the time-base
unit coincides
with the
end of each sweep,
and
results in alternate-mode
vertical
switching. The
output
from
the divide-by-two
portion of the
Countdown
Circuit
(U640A-U640B) is sent
via contacts
B21
of
J601
and
J602
to the channel-switching
circuits
incorporated within dual-
trace vertical plug-in
units. The
outputs
from
the divide-by-
3-1
Circuit
Description—
5103N
four portion
of
the
Countdown Circuit (U640C-U640D) are
used
for
plug-in
switching; one output is sent to contact
A15
of
J604
to produce
plug-in switching on the single-
beam-display
auxiliary board, and the other output is sent
via contact
B21
of
J603
to
produce dual-sweep
switching in
dual time-base
units. The
vertical
mode
switching
sequence
and some of the
display combination possibilities are
fully
discussed under
General Operating
Information
in the
Operating I nstructions
section of
this manual.
Auxiliary Boards
Because
switching
between plug-ins
is
required for
simul-
taneous
viewing of
displays
on
single-beam
cathode-ray
tubes and not
required
for
use with dual-beam cathode-ray
tubes, an
auxiliary board is
supplied
with each display unit
to
provide the correct
signal-routing function.
An auxiliary
board plugs into
J604
on the Interface circuit board,
and
becomes part
of the Interface circuit. The single-beam
auxiliary
board
accepts
the push-pull signal outputs from
both
vertical plug-ins. Emitter
followers
Q701,
Q703,
Q711,
and
Q713
provide
a
high-impedance
input to two
pairs of grounded-gate FET amplifiers,
Q702-Q704
and
Q712-Q714.
The
switching circuit consists of Q721
and
Q722,
connected as a
comparator. Plug-in
“on'' logic levels
are applied
to
the switching circuit in addition to the
switching signal
from the Countdown Circuit. The
switching circuit permits
only one pair of amplifiers
to be
on
at a
time, thus
permitting only one of the two vertical
plug-in signals to pass
to the Vertical Amplifier. In the
chopped switching mode, the
switching between pairs of
amplifiers occurs at a
50-kilohertz rate (switching occurs on
both the negative-
and positive-going transition), and in
the
alternate mode, switching
occurs at the end
of
every second
sweep.
If
no “on"
logic level is applied to the switching
circuit
from either vertical plug-in, Q702 and Q704 will
remain on, passing
any signal
from
the left vertical plug-in.
The
dual-beam
auxiliary
board has
no switching circuit.
It routes
the signal
from the left vertical
plug-in to the
Vertical
Amplifier circuit on the Interface circuit board,
and amplifies the
signal from the right vertical plug-in.
The
amplifier circuit on
the dual-beam auxiliary board is identi-
cal
to
the Vertical
Amplifier
which
is discussed next, and
consists
of
Q701,
Q702, Q711,
and Q712. The output of
this amplifier is sent
directly to the lower-beam deflection
amplifier in the display
unit.
Vertical
Amplifier
The Vertical
Amplifier circuit provides
approximately
10X
amplification of the vertical signal before passing it
to
the vertical deflection
amplifier in the display
unit. The
Vertical
Amplifier consists of
Q650, Q658, Q660, Q668,
and their associated
passive components, connected in
a
differential configuration.
The output signal is in
phase
with the output
of the vertical plug-in.
Horizontal
Amplifier
The
Horizontal
Amplifier
consists of
Q670, Q678,
Q680,
Q688,
and
their
associated
passive
components.
The
circuit
is nearly
identical
to the
Vertical
Amplifier
just
described.
It
receives
a push-pull
input
directly
from
the
horizontal
plug-in compartment
via contacts
A7, A13,
B7,
and
B13
of
J603.
The two
halves of
this amplifier
are
balanced
in the
quiescent condition
by adjustment
of
R675,
Horiz
Cent.
The output of
the
Horizontal
Amplifier
is sent
to the
horizontal
deflection
amplifier
in the
display
unit.
POWER SUPPLY
General
The
Power
Supply
circuit
provides
the
low-voltage
operating
power for
the oscilloscope
system from
three
regulated
supplies and
three
unregulated
supplies.
Elec-
tronic
regulation
is used
to provide
stable,
low-ripple
out-
put
voltages.
The circuit also
includes
the calibrator
circuit
to
produce an
accurate
square-wave
output.
Power
Input
Power
is applied
to the primary
of transformer
T801
through
the
display
unit (fuse
F201, thermal
cutout
S200,
and Power
switch
S201),
and the line-selector
block, P810.
The
line-selector
block allows changing
the
primary -winding
taps of
T801 to
fit
different
line requirements.
Low-Voltage
Rectifiers
and
Unregulated Outputs
The
full-wave bridge
rectifiers
and associated filter
com-
ponents in
the secondaries of
T801 provide filtered
DC
voltages for
operation of the
oscilloscope
system or for
regulation
by the
Low-Voltage
Regulators.
The
unregulated
outputs
are +200 volts, +38
volts,
and
—38
volts.
The
+205-volt and
+38-volt
outputs to the
display unit are fuse-
protected
by F810 and F835
respectively.
Low-Voltage
Regulators
-30-Volt
Supply.
The
-30-Volt
Supply,
besides
pro-
viding
power
to
circuitry
throughout
the
instrument,
provides
a
reference-voltage
source
to
establish
operating
levels
for the
feedback
regulators
in the
+30-Volt
and
+5-Volt
supplies.
The regulator
for
the
-30-Volt
Supply is
a
feedback
amplifier
system which
operates
between
ground
and the
unregulated
-38
volts.
Current
to the load
is delivered
by the
series-pass
transistor,
Q860,
and the
supply
voltage
is
established
by the
drop
across
R877,
R878,
and
R879.
The
feedback
path
is through
R875,
Q875,
and
Q865 to the
base of
Q860.
Any variation
in
output
voltage
due
to ripple,
change
of
current
through
the
load,
etc., is
immediately
transmitted
to
the base
of
Q860
and
nullified
by
a change
in
Q860 conduction,
thus
main-
3-2
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