Tektronix 519 User manual

TYPE 519
| Cathode-Ray
Oscilloscope
| | OPERATING INSTRUCTIONS
TEKTRONIX, INC.
PO Box 500 Beaverton, Oregon .

Specifications
Section
1
General information
The Tektronix Type 519 Oscilloscope is a
wide-band laboratory type instrument designed
expressly for the observation and measurement
of
high-frequency
phenomena.
Fast
linear
sweeps, high crt accelerating potential, high
sensitivity, wide-band trigger system, and
extreme bandwidth permit single-shot photo-
graphic
recording
of
fractional
nanosecond
signals. An internal delay line in the vertical
channel of the instrument eliminates the need
for adjusting cable lengths. Since the length
of the delay line remains constant, the band-
width of the Type 519 also remains constant.
The Type 519 incorporates an adjustable
repetition rate fast-rise pulse generator and
a fast-rise calibration-step generator which
can
supply
waveforms
to
check
the
calibration
of
the
oscilloscope
itself
or
drive
external
devices.
These
generators
meet
most
require-
ments to complete a test setup. |
VERTICAL-DEFLECTION SYSTEM
Vertical Deflection Factor--With Type T519A
CRT, nominally 10 volts per cm. ,
Passband--With Type T519A CRT, dc to l
gigacycle* (3db down). .
Risetime--With
Type
519A
CRT,
less
than
0.35
nanosecond.
Input Impedance--125 ohms.
Maximum
Allowable
Input
Power
to
Vertical
Channel--1.8
watts
(+or-
15
volts
dcor
rms).
Maximum Allowable Peak Signal Amplitude--
+or- 100 volts.
Internal Signal Delay--45 nanoseconds, fixed.
Voltage
Standing
Wave
Ratio--Nominally
1,2:1
from dc to 1 gigacycle.”*
*Gigacycle = 10” cps.
T
|
Specifications
-
Type
519
TRIGGER
Triggering Signal Sources--Internal from +or-
applied signals, internal from the Rate Gen-
erator, internal from the Calibration-Step
Generator, and External.
External
Triggering
Signal
Requirements--
Pulse
amplitude:
20
millivolts.
Pulse
dura-
tion:
1
nanosecond
or
ionger.
Maximum
permissible
external
triggering
signal:
+or-
10
volts
peak.
Internal
Triggering
Signal
Requirements
-
-Pulse
amplitude:
sufficient
signal
to
‘produce
a
2
trace-width
deflection
on
the
screen.
Dura-
tion:
1
nanosecond
or
longer.
Repetition
rate:
O.to
1
gigacycle.
Countdown--Triggering
circuits
count
down
from
triggering
signal
frequencies
higher
than
400
kc.
Sine-wave
trigger
requirements:
0.1
mc
to
1000
mc
(1
gc),
20
mv
peak-to-peak
~
external
trigger
input
or
150
mv
peak-to-
peak
signal
to
vertical
input.
Pulse
Amplitude
or
Sync--Single
control
adjusts
pulse
triggering
level
or
high-frequency
sync.
An
additional
control
provides
vernier
sync.
Delay--0
to
35
nanoseconds
sweep-start
delay.
Permits
sweep
to
display
a
selected
time
interval.
TIME BASE.
Sweep
Rates--Nine
ranges:
2,
5,
10,
20,
50,
100,
200,
500,
and
1000
nanoseconds
(1
microsecond)
per
centimeter,
Accuracy--Typically
within
2%
of
indicated
rate
on
all
ranges
except
the
2
nanosecond
range which
is
within
3%.
These
tolerances
apply
to
all
ranges
except
for the
first
2
nanoseconds
or
2
mm
(whichever
is
larger)
portion
of
any
of
the
above
rates.
Single
-
Sweep--Normal
or
single
sweeps
selected
by
front
panel
switch
and
reset
by
push-button.
Page l

+ Trigger Output--1-volt into 50 ohms upon
triggering.
Delayed +Gate--l-volt pulse into 50 ohms at
start of sweep; hence, time-dependent upon
setting of sweep-delay control.
RATE GENERATOR
Risetime--Less than 0.8 nanosecond.
Pulse Repetition Rate--3 pps to 30 kc, con-
tinuously variable.
Pulse Duration--10 nanoseconds.
Output Impedance--50 ohms.
Amplitude--Approximately +15 volts.
CALIBRATION-STEP GENERATOR
Risetime~-approximately 0.1 nanosecond.
Step Repetition Rate-- Adjustable 250 to 1000 cps,
normally operated at reed-switch resonant
frequency near 750 cps.
Output Impedance--125 ohms.
Amplitude--Into 125 ohms, 0 to 10 volts. Into
50 ohms through T125/T50 adapter, O to
1 volt. Voltages applied to both impedances
are continuously variable and calibrated.
Uncalibrated voltages up to 50 volts into 1252.
Polarity--The output polarity can be selecte"
by a front-panel switch.
CATH ODE-RAY TUBE
Type--Tol9A
Phosphors--Type P11 phosphor standard (rec-
ommended for single - shot photographic
recording of fastest sweep rate), Other
phosphors available on special request.
Usable Viewing Area--Two centimeters, ver-
tical, six centimeters horizontal.
Accelerating Voltage--24 kv.
Spot Diameter--0.004 inch at normal intensity.
Page 2
Deflection--Electrostatic. Traveling-wave ver-
tical deflection system with conventional hori-
zontal deflection plates.
CONSTRUCTION AND POWER
REQUIREMENTS
Construction -- single - unit construction with
light-weight aluminum-alloy chassis and four-_
piece vinyl-finish cabinet. Side panels, top
and bottom panels are separately removable.
Ventilation--Filtered forced air with protective
thermal cut-out insures safe operating temp-
eratures.
Dimensions -- Approximately 22-1/4" high,
14-3/4" wide, and 25-1/4" long.
Net Weight--Approximately 99 pounds.
- Power Requirements--105 to 125 or 210 to
250 volts, 50 to 60 cycles, 650 watts.
ACCESSORIES
1 -- 1252 Termination (017 -007)
1 -- 1252 Adapter T50/T125 (017-008)
2--1252 Insertion Units (017-013)
1 -- 1252 Adapter N50/N125 (017-015)
1 -- 1252 Adapter T50/N125 (017-017)
1 -- 1252 Coupling Capacitor (017-018)
1 -- 1252 1KMC Ringing Crt (017-019)
1 -- 1252 1 nsec Delay Cable (017-507)
1 -- 1252 2 nsec Delay Cable (017-508) ©
1 -- 1252 5nsecDelay Cable (017-509)
1 -- 1252 10nsec Delay Cable (017-510)
1 -- Set of spare miscellaneous cable connector
parts consisting of:
Double Button Assy. (017-032)
Panel Adapter Assy. (017-033)
1252 Cable Connector (017 -035)
Specifications - Type 519 T

2 Spare Reed Switches (260-362) 1 -- 3-conductor Power Cord (161-010)
1 -- Viewing Hood (includes attached: bezel) 1 -- Power Cord Adapter (013-013)
1 -- Accessory Box
Introduction
1 -- Instruction Manual
Operating Information
Section 2
important to have an understanding of the
operation of each control and its function,
The Type 519 Oscilloscope is a high sweep This section of the Operator's Manual is intended
rate laboratory instrument designed for observ- to provide this understanding and other basic
ing, measuring, and photographically recording information. A brief description of each of
phenomena in the nanosecond (millimicrosecond) the front-panel controls follows. Front-panel
region, However, before the instrument can lettering is shown in Fig. 2-1.
be successfully applied in actual use, it is
SCALE ILLUM.
ASTIGMATISM
INTENSITY
FOCUS
Graticule
Control
NANOSEC/CM
DELAY
NORMAL-SINGLE
SWEEP
CYCLES/SEC
‘MULTIPLIER
FUNCTION OF CONTROLS
CRT
Adjusts the brightness of the graticule markings.
Used in conjunction with the FOCUS control to obtain a round spot
and a sharply focused trace.
Adjusts the brightness of the trace.
‘Used in conjunction with the ASTIGMATISM control to focus the
oscilloscope display.
A knurled knob located below the center of the graticule permits
graticule to be moved down when not used.
TIME BASE
Selects the time-base rates.
Sets the delay time duration. Delays start of sweep with respect to
trigger signal input.-
Selects either normal or single-sweep operation.
RATE GENERATOR
Selects the significant figures for the RATE GENERATOR output
frequency.
Multiplier for the CYCLES/SEC control. Should be set to OFF position |
when Rate Generator is not being used.
Operating Information - Type 519 Page 3

RANGE
VARIABLE
VOLTS
POLARITY
REED SWITCH
DRIVE
FREQUENCY
PULSE AMPLITUDE
OR SYNC*
VERNIER SYNC
FUNCTION*
G AIN*
TRIGGER SOURCE
CALIBRATION-STEP GENERATOR
Selects either of two full-scale amplitudes of the calibrator step,
a variable pulse amplitude, or a standby condition. Should be set
to STANDBY position when Calibration-Step Generator is not being
used,
Permits the step waveform to be preset to an arbitrary desired
amplitude up to about 50 volts.
Sets the output voltage amplitude of the calibration-step waveform.
Selects either positive- or negative-going output step waveform.
Adjusts reed-switch magnetic excitation or permits single closure.
Controls frequency of the reed-switch magnetic excitation to reduce
multiple contact bounces.
TRIGGER
Rejects triggers below selected amplitude or adjusts synchronization.
Used in conjunction with PULSE AMPLITUDE or SYNC control to
synchronize the sweep.
Permits choices of triggered or synchronized displays, depending
upon nature of input signals.
Selects proper gain for the triggering signal.
Selects the triggering signal source and polarity.
*Also see TRIGGER OPERATION section of front-panel, Fig. 2-1.
VERTICAL
AXIS ROTATION
HORIZONTAL
DIM ADJ.
ON ©
Page 4
POSITIONING
Adjusts the vertical position of the trace.
Aligns the trace parallel to the horizontal centerline.
Adjusts the horizontal position of the trace.
POWER
Used to adjust brightness of adjacent pilot light after 45 seconds
warm-up.
Main power switch.
Operating Information - Type 519 T

PRELIMINARY INSTRUCTIONS
Cooling
A blower maintains safe operating temp-
erature in the Type 519 Oscilloscope by drawing
air
through
a
filter
and
circulating
it
over
the
components.
Therefore,
the
instrument
must be placed so that the air intake and
cabinet ventilating holes are not blocked. The
air filter must be kept clean to permit adequate
air
flow.
A thermal cutout switch will disconnect the
dc power if air flow is restricted or ambient
temperature
is
too
high.
DC
power
will
return
when the temperature drops to a safe value.
The pilot lamp will increase to full brightness
in event of loss of dc power. The blower
continues to cool the interior and reduces
the time the thermal switch remains open.
Power Requirements
_ The regulated power supplies in the Type
- 519 Oscilloscope will operate with line vol-
tages from 105 to 125 volts (117 nominal)
or from 210 to 250 volts (234 nominal), The
line voltage for which your instrument is
wired at the factory is indicated on a metal
tag fastened to the rear panel near the power
receptacle, Power wiring may be changed
for either 117- or 234-volt operation in com-
pliance with the information given in Fig. 2-2.
The power transformer is wound with two
117-volt primaries which can be connected
in parallel for 117-volt operation or in series
for 234-volt operation. Since the blower motor
is connected across only one of the trans-
former primaries, no change in the motor lead
connections is required. When power wiring
is changed, the voltage indicated on the metal
tag should be covered with another tag which
conforms to the new operating voltage.
For maximum dependability and long life,
the line voltage applied to the Type 519 Oscillo-
scope should be near the design center (117 7
or 234 volts). If the line voltage exceeds
the operating limits or has a poor waveform.
(distorted sine-wave peaks), unstable power
supply operation may result. Observe for proper
line voltage and waveform before checking
for other causes of unstable operation.
T Operating Information - Type 519
Fuse Requirements
. When the Type 519 Oscilloscope is con-
nected for 117-volt operation, use a 7-amp
slow-blowing type fuse. When the instrument
is connected for 234-volt operation, use a
4-amp slow-blowing type fuse.
Time Delay
A time delay relay used in the Type 519
delays. operation of the instrument for approx-
imately 45 seconds after the power switch
is operated. The relay allows a brief tube-
warmup period before the dc operating voltages
are applied. When the ac-power pilot light
dims, the instrument is ready for use.
If the ac power is interrupted for only an
instant, the normal 45-second delay will occur
before the instrument returns to full operation.
Dim Adjustment
The DIM ADJ. control is a screwdriver
adjustment which controls the brightness of
the ac-power pilot light after the 45-second
delay period. The control may be adjusted
to any desired setting. Normally, it is adjusted
to a setting which will reduce glare from
the pilot light when waveform observations
are being made in a darkened room.
FIRST-TIME OPERATION
To place the Type 519 in operation for the
first time, the following procedure is suggested:
1. Set the front-panel controls as follows:
POWER Off
DIM ADJ. Centered
FOCUS Centered
INTENSITY Fully counterclockwise
ASTIGMATISM Centered
SCALE ILLUM. Centered
DELAY Min.
NANOSEC/CM rs)
Page 5

MULTIPLIER X1000
CYCLES/SEC 10
CALIBRATION- Standby
STEP GENERATOR
controls
TRIGGER SOURCE RATE GEN,
GAIN , NORMAL
FUNCTION PULSE
VERNIER SYNC centered
PULSE AMPLI-
TUDE or SYNC
Fully counterclockwise
VERTICAL Centered
HORIZONTAL Fully clockwise
2. Connect the power cord to the rear of .
the instrument and to the source of power.
The line voltage for which the instrument
is wired at the factory is indicated near
the power cord receptacle.
3. Set the POWER switch to ON.
4, Allow about .45 seconds for the pilot lamp
to suddenly dim , indicating that dc-operating
voltages are applied and the instrument
is ready for use.
5. Advance the INTENSITY control until a
visible spot appears near the left center
of the screen.
CAUTION
Do not turn the intensity so high
that a bright glow surrounds the
spot. Excessive undeflected bright-
ness may damage the screen in a
few seconds.
6. Adjust the FOCUS and ASTIGMATISM con-
trols in conjunction with each other to
produce a small round spot.
7. Advance the PULSE AMPLITUDE or SYNC
control fully clockwise to obtain a hori-
zontal sweep trace across the screen.
Readjust the INTENSITY control for suitable
trace brightness.
Page 6
8. Rotate the HORIZONTAL positioning control
to position the start of the trace at the left
side of the graticule.
9, Adjust the AXIS ROTATION control until
the trace is parallel to the horizontal
centerline of the graticule.
10. Connect a T50/N125 adapter to the +RATE
902 connector so that the 50-ohm fittings
match,
ll. Connect a 2-nsec 125-ohm cable from the
125-ohm end of the adapter to the SIGNAL
125Q connector.
12. Rotate the PULSE AMPLITUDE or SYNC
control slowly counterclockwise until a
stable display of the Rate Generator pulse
is obtained. Center the waveform vertically
using the VERTICAL positioning control.
13. Adjust the FOCUS, INTENSITY, and ASTIG-
MATISM controls until a sharp trace with
adequate intensity is obtained. These con-
trols are slightly interdependent and will
require readjustment to obtain the best
trace.
An external signal and/or trigger may now
be applied to the input connectors, If external
triggers are used, set the TRIGGER SOURCE
switch to+ or - EXT.
CRT CONTROLS AND GRATICULE
Intensity
The INTENSITY control is used to adjust
the brightness of the oscilloscope display.
Thus, compensation can be made for changes
in brightness resulting from changes in the
triggering rate or time-base rate. The INTEN-
SITY control is rotated clockwise to increase
brightness and counterclockwise to decrease
brightness. Care must be taken when using
the INTENSITY control that the brightness is
not turned up to the point where the phosphor
on the face of the cathode-ray tube (crt) becomes
permanently damaged. The intensity of the
beam should never be turned up to the point
where a bright halo forms around a stationary
spot.
Operating Information - Type 519 T

Focus and Astigmatism
The FOCUS and ASTIGMATISM controls
operate collectively to permit a sharp, clearly
defined spot or trace to be obtained. The
proper setting of the ASTIGMATISM control
is obtained by rotating the FOCUS control
fully clockwise, setting the PULSE AMPLITUDE
or SYNC control fully counterclockwise, and
setting the INTENSITY control high enough so
the spot is visible (it may be necessary to
adjust the POSITIONING controls), Then adjust
the ASTIGMATISM control to obtain the most
circular spot possible. The FOCUS control
is then adjusted to reduce the spot diameter
as much as possible. This method of spot
adjustment is made with no input signal applied ©
to the SIGNAL 125 input connector. Also,
the ambient light in the room should be kept
low or the viewing hood should be used so
the spot can be observed at a low intensity
level.
Another method for adjusting the spot size —
would be to couple a 10-volt step waveform
from either the RATE GENERATOR or. the
CALIBRATION-STEP GENERATOR to the SIG- |
NAL 12592 connector. When the step waveform
is displayed on the screen, the FOCUS control
is adjusted to narrow the trace during the
rising portion of the waveform. The ASTIG-
MATISM control, is used to narrow the trace
along the horizontal portion of the same wave-
form. Since the two controls interact, repeat
the procedure to obtain a sharply-defined trace
in both the vertical and horizontal direction.
Graticule
The disappearing graticule used withthe Type
519 Oscilloscope is accurately marked with 6
horizontal and 2 vertical 1-centimeter divisions.
The markings on the horizontal centerline are
9 millimeters apart; those on the vertical
centerline are 2 millimeters apart. The
graticule markings allow time and voltage
measurements to be made from the oscillo-
scope screen.
To make the graticule disappear for a clear
view of the screen, loosen the knurled knob
located just below the graticule and slide it
downward the full length of the slot. Tighten
the knob. To make the graticule reappear,
reverse the process.
T Operating Information - Type 519
The graticule cover and mask assembly is
held securely in place by four slotted graticule
nuts and is provided with hinge fittings for
mounting the viewing hood. In addition, the
hinge fittings allow quick removal of the viewing
hood so that a Tektronix Model C12 or Model
C19 camera may be mounted. The Model C19
camera is especially designed to photograph
the fast sweeps of the Type 519 Oscilloscope,
When the camera is not being used, it can
be unlatched and swung away from the crt
screen.
Graticule IIlumination
The graticule is illuminated by two lamps
located at the top edge of the graticule. The
SCALE ILLUM,. control, located below the
oscilloscope screen, is rotated clockwise to
increase the illumination of the graticule mark-
ings and counterclockwise to decrease the
illumination.
Camera Jack
A camera jack, marked 6.3V CAMERA, pro-
vides a 6.3-volt source for use with the Type
C19 camera. When the camera plug is inserted
in the jack, the SCALE ILLUM control and
oscilloscope graticule lights are automatically
disconnected. The 6.3-volt source is utilized
by the camera to project a virtual image
graticule on the face of the crt. During pro-
jection of the image graticule, the oscilloscope
graticule should be dropped out of view.
POSITIONING
Two controls, VERTICAL and HORIZONTAL,
are used to allow the trace to be positioned
to the desired point on the oscilloscope screen.
A third positioning control, AXIS ROTATION,
is used to align the trace with the horizontal
centerline of the graticule.
The VERTICAL position control has suf-
ficient range to allow the trace to be positioned
completely off the top or bottom of the screen
or to any intermediate point. The trace moves
up when the control is rotated clockwise and
down when the control is rotated counter-
clockwise.
The HORIZONTAL position control causes
. the trace to move to the right when it is
rotated in the clockwise direction and to the
Page7

left when it is rotated counterclockwise. The
total horizontal positioning range of the control
_is about 2 centimeters.
The AXIS ROTATION control is a screw-
driver adjustment located between the VER-
TICAL and HORIZONTAL controls. This adjust-
ment permits the trace to be rotated about an
axis through the center of the screen. The
control is adjusted to align the trace parallel
to the horizontal centerline.
VERTICAL-DEFLECTION SYSTEM
Input Signal Connection
The electrical signal to be observed is
applied externally through a 125-ohm coaxial
cable to the SIGNAL 1252 connector. The
Signal passes internally first through atrigger-
energy takeoff, then through a 45-nsec delay
cable to the distributed vertical deflection
plates of the crt. The signal causes the spot
to be deflected vertically. The spot traces out
the signal waveform on the screen as the spot
is deflected horizontally by the horizontal sweep
circuits. The vertical size of the displayed
waveform is adjusted to a suitable amplitude
by inserting external attenuators or an amplifier
in series with the signal-carrying cable. Or,
if the CALIBRATION-STEP GENERATOR is
being used as the signal source, the vertical
amplitude of the waveform can be adjusted
by means of the CALIBRATION-STEP GEN-
ERATOR front-pane! controls.
The vertical sensitivity of the Type 519
Oscilloscope is the same as the sensitivity
of the crt mounted.in the instrument. Each
crt for the Type 519 is measured for sensitivity
and risetime at the factory. These measure-
ments are then clearly recorded on the crt
face mask. The sensitivity measurement can
be checked at any time by using the CALI-
BRATION-STEP GENERATOR.
To check the measurement, connect a 125-
ohm cable from the OUTPUT 125Q connector
to the SIGNAL 125 connector. Set the (CALI-
BRATION-STEP GENERATOR) RANGE switch
to 10V TO 125Q and rotate the VOLTS control
to 10.00. Adjust the oscilloscope front-panel
controls for a stable presentation of the step
waveform. Rotate the VOLTS control counter-
clockwise until that portion of the waveform
located 2 nsec after the rise is exactly one
Page 8
centimeter high. The exact vertical sensitivity
in volts per centimeter can now be readdirectly
from the VOLTS dial.
For example, if the VOLTS dial shows a
. reading of 8.70, the vertical deflection factor
is 8.7 volts per centimeter.
When connecting the oscilloscope to any
signal source, the connections should be made
directly through 125-ohm cables or through
suitable impedance matching devices to the
SIGNAL 125Q connector. If the signal amplitude
is too great, it will be necessary to attenuate
the signal to a usable level before applying it
to the SIGNAL 125 connector. This can be
done by inserting a 125Q attenuator (or known
attenuation factor) between the signal source
and the SIGNAL 125Q connector. Attenuators
may be used individually or may be " stacked"
(connected in series).
If the signal amplitude is too low to produce
sufficient vertical deflection, an external ampli-
fier can be inserted between the signal source
and the SIGNAL 1252 connector. However, if
the amplifier does not provide the correct
‘input and output impedance, or has limited
bandwidth, signal waveform errors may result.
In addition, if the amplifier stages do not
operate linearly the signal will not be repro-
duced faithfully on the crt.
In general, to obtain an accurate waveform
display and to prevent unwanted reflection of
high-frequency waveforms or of fast-rise
pulses, all cables should be terminated in
their characteristic impedances.
Delaying the Signal +
The Type 519 Oscilloscope contains a fixed
signal-delay line which permits the sweep to
be well under way before displaying the leading
edge of an input signal. By means of the fixed
signal-delay line, the input signal is purposely
delayed 45 nanoseconds before arriving at the
vertical deflection plates.’ This amount of delay
allows sufficient time for the trigger circuits
to process the trigger signal and start the sweep.
The DELAY control delays the start of the
sweep from O to 35 nanoseconds. Within this
range of time, the DELAY control can be
used to select the display time and thus
apparently position the waveform horizontally
on the screen.
Operating Information - Type 519 T