Tektronix 114 User manual

INSTRUCTION
MANUAL
Serial Number _____________
114
PULSE GENERATOR
Tektronix, Inc.
S.W. , Millikan Way • P. O. Box 500 • Beaverton, Oregon 97005 • Phone [phone] • ables: Tektronix
070-465
265

WARRANTY
All Tektronix instruments are warranted
against defective materials and workman 
ship for one yeor. Tektronix transformers,
manufactured in our own plant, are war 
ranted for the life of the instrument.
Any questions with respect to the war 
ranty mentioned above should be taken up
with your Tektronix Field Engineer.
Tektronix repair and replacement-part
service is geared directly to the field, there 
fore all requests for repairs and replace 
ment parts should be directed to the Tek 
tronix Field Office or Representative in your
area. This procedure will assure you the
fastest possible service. Please include the
instrument Type and Serial number with all
requests for parts or service.
Specifications and price change priv 
ileges reserved.
opyright ,c 1965 by Tektronix, Inc.,
Beaverton, Oregon. Printed in the United
States of America. All rights reserved.
ontents of this publication may not be
reproduced in any form without permis 
sion of the copyright owner.
Type 114

Type 114
Type 114 Pulse Genero or

-
7
r
CONTENTS
Warranty
Section 1
haracteristics
Section 2
Operating Instructions
Section 3
ircuit Description
Section 4
Maintenance and alibration
Section 5
Parts List and Diagrams
A list of abbreviations and symbols used in this
manual will be found on page 5-1. hange in 
formation, if any, is located at the rear of the
manual.
Type 114

SECTION 1
CHARACTERISTICS
In roduc ion
The Type 114 Pulse Generator is a general purpose pulse
generator. Transistorized circuitry is used throughout, with
most of the components being mounted on an etched circuit
board.
The Type 114 Pulse Generator is versatile. The repetition
rate, width, and amplitude of the output pulse are individual 
ly selectable by range and by variable control within each
range. Front-panel connectors are provided for the pulse out 
put, trigger output, and external trigger input. A single front 
panel switch selects both the amplitude range and polarity
of the output pulse. The trigger output pulse is set by a front 
panel switch to occur on the desired edge (leading or trailing)
of the output pulse. In cases where the Type 114 is set for a
pulse width longer than the pulse repetition period, a built-
in feature automatically counts down the repetition rate to
permit the width of the output pulse to remain at the value
selected (such operation is indicated by a Width > Period
light). In addition, two Type 114's can be connected together
so that the output pulse of the second unit is delayed by the
pulse width (up to 10 ms) of the first unit.
short circuiting the OUTPUT connector will not damage the
instrument.
WARNING
The Type 114 should never be connected to an inductive
load, or any load that will produce a current which will feed
back into the instrument.
TABLE 1-1
Amplitude
Range
Pulse
on
Pulse
off
±1 to 3 V
≈ 20 Ω 19 Ω to 22 Ω
±3 to 10 V
28 Ω to 48 Ω
30 Ω to 95 Ω
Elec rical
Pulse Period. The PERIOD switch and associated VARI 
ABLE control provide continuously variable pulse periods
from 1 µ sec to 100 msec (pulse repetition rates from one mil 
lion pulses per second to 10 pulses per second). An EXTER 
NAL TRIGGER position on the PERIOD switch permits exter 
nal control of the pulse period. With the VARIABLE control
at the AL end of its range and the WIDTH > PERIOD light
unlit, the period accuracy is within ±3% of the indicated
value. Jitter is typically less than 0.05% of pulse period
+2 ms.
Pulse Wid h. The WIDTH switch and associated VARI 
ABLE control provide continuously variable pulse widths from
l 00 n sec to 10 msec. With the width VARIABLE control at
the AL end of its range, the width accuracy is within
±3% of indicated value. Jitter is typically less than
0.05% plus ½ nsec. An additional SQUARE WAVE
position on the WIDTH switch disables the variable width
feature and changes the output to a square wave whose
repetition rate is determined by the PERIOD controls.
Period error in the square wave mode is < ±5%.
Ou pu Polari y and Ampli ude. The AMPLITUDE switch
provides for either polarity output with two amplitude ranges
(1 V to 3 V and 3 V to 10 V). The VARIABLE control permits
the output to be varied within the voltage ranges. Aber 
rations (overshoot, rolloff, preshoot, or ringing) amount to
less than 5% at maximum amplitude.
Ou pu Impedance. The output impedance of the Type
114 is given in Table 1-1. The figures given are typical and
are dependent upon the setting of the AMPLITUDE — VARI 
ABLE control. Load impedance is not critical. Temporarily
Ex ernal Trigger Inpu . External triggering requires a
positive trigger signal of 2 to 20 volts and having a risetime
of 1 µ sec or less. Triggering signals up to 2 Mc may be used.
Trigger Ou pu . The trigger output pulse into an open
circuit is approximately 3 volts; into a 50 Ω termination, the
trigger output pulse is approximately '/ 2 volt. A front-panel
switch allows the output trigger pulse to be set to occur at
the leading edge or the trailing edge of the main pulse.
Inpu Power Requiremen s. ≈ 15 watts; 50 to 400 cps,
94.5 to 137.5 or 189 to 275 volts, ac.
Warm-up Time at +25° ±5° . Five minutes for rated
accuracies.
Environmen al
Opera ing
Temperature
Altitude
Non-Opera ing
Temperature
Altitude
Mechanical
Dimensions
onnectors
Accessories
0° to +50°
15,000 feet maximum
— 40° to +65°
50,000 feet maximum
Approximately 9" X 6" X
12 ½" overall
Front-panel connectors are
BN type.
See standard accessory lists in this manual for accessories
supplied with each instrument. For optional accessories, see
the current Tektronix, Inc. catalog.
1-1

Charac eris ics — Type 114
GLOSSARY OF TERMS
MPPS
Bistable
(multivibrator)
alibrate
A circuit that has two stable states and
requires two input pulses to complete a
cycle.
To check or correct the graduation ac 
curacy of quantitative indicators.
AL (calibrated)
position
An index position to which an otherwise
ungraduated control is set when a quanti 
tative measurement must be made.
atching or
clamping
diode
Establishes the + or — extremity of a volt 
age excursion.
ount-down (of
pulses) circuit
Delayed pulse
Overshoot
PPS
Preshoot
Pulse amplitude
Pulse duration
A circuit, such as a bistable, whose output
consists of pulses fewer in number (usu 
ally a submultiple) than the pulses applied
to the input(s).
A pulse occurring after a preselected in 
terval following an event used as a time
reference point.
Delayed trigger
Duty factor
(of pulses)
Enabling pulse
External trig 
ger (pulse)
Falltime
Generally, a narrow, delayed pulse.
For periodic pulses, the duty factor (often
called duty cycle) is equal to the duration
(width) of a pulse divided by the pulse
period.
A pulse which opens a normally closed
electric gate, or otherwise permits an oper 
ation for which a pulse input is a neces 
sary condition.
An enabling pulse derived from a source
external to the circuit or equipment where
a particular operation requires an enabling
pulse with certain characteristics (time de 
layed, duration, etc.).
The time required by pulse waveform to
fall from 90% of its maximum value to
10% of its maximum value. Not neces 
sarily equal to risetime.
Jitter
KPPS
Pulse period
Pulse Repeti 
tion Frequency
Pulse width
Quiescent
Ramp voltage
Ringing
Risetime
Short-duration instability (of a signal); ran 
dom small departures from regularity.
Kilopulses per second.
Monostable
(multivibrator)
A circuit having one stable and one semi 
stable state. A trigger pulse drives the
circuit into the semistable state, where it
remains for a predetermined time before
returning to the stable condition.
Sampling
system
Trigger
Megapulses per second.
When changing from one voltage level to
another, a momentary excursion greater
than the change desired.
Pulses per second.
A small negative excursion immediately
preceding a positive-going pulse, or vice
versa.
The amplitude of a pulse is any term indi 
cating the magnitude of the pulse.
The time interval between the first and
last instants at which the pulse voltage (or
current) reaches some specified percentage
of the peak voltage (or current) of the
pulse.
The pulse period in a sequence of periodic
pulses is the elapsed time between any
given point on one of the pulse waveforms
and the same point on the following pulse.
The number of periodic pulses that occur
in a given unit of time. Also expressed as
pulse repetition rate.
See pulse duration.
At rest — specifically, the condition of a
circuit when no input signal is being ap 
plied and/or no change is taking place.
A voltage waveform that rises at a steady
rate. For example, at 10 volts per second..
High-frequency damped oscillations caused
by shock excitation of high-frequency res 
onances, or, a damped oscillation in the
output signal of a system as a result of a
sudden change in the input signal.
The risetime of a pulse is taken as the time
required for the leading edge of the pulse
to increase from 10% of its maximum
value to 90% of its maximum value.
A method that takes amplitude samples
from a repetitive input signal with each
sample at a progressively later time, then
reconstructs these samples into a replica of
the original waveform at a much lower
frequency.
A signal that starts action in another
circuit.
1-2

SECTION 2
OPERATING INSTRUCTIONS
Fron -Panel Con rols, Indica ors, and Connec ors
(See Fig. 2-1.)
The function of each item on the Type 114 front panel is
given in the following tabulation.
POWER
Switch This toggle switch completes the circuit
to the primary of the power transformer.
Indicator The white lamp to the right of the POWER
switch lights when the Type 114 is en 
ergized.
PERIOD
Switch This switch selects the basic range of
pulse period. When the switch is set to
EXTERNAL TRIGGER — INPUT, the Type
114 provides width and amplitude control
for externally generated pulses applied to
the INPUT connector. Note that “ 100 mS"
does no indicate a switch position, but
is instead an index for the VARIABLE
control.
VARIABLE This control has a range of 10:1 or more,
ontrol and provides continuous coverage between
the steps of the PERIOD switch.
EXTERNAL BN connector to which the external trig-
TRIGGER- ger is applied when externally triggering.
INPUT on 
nector
WIDTH
Switch This switch selects the basic ranges of
pulse width. Note that the word “ 10 mS ”
does no indicate a switch position, but is
instead an index for the associated VARI 
ABLE control.
When the WIDTH switch is set to SQUARE
WAVE, the output of the Type 114 is a
square wave whose period is selected by
the PERIOD controls.
VARIABLE This control provides continuous cover-
ontrol age between the steps of the WIDTH
switch and has a range of 10:1 or greater.
WIDTH > With the flexibility provided, it is possible
PERIOD In- to set the controls so that the width of the
dicator light pulse selected exceeds the period selected.
When this occurs, the Type 114 counts
down the repetition rate and lights the
WIDTH > PERIOD light. The pulse width
remains as selected, but the pulse period
is no longer that selected by the PERIOD
controls.
AMPLITUDE
Switch Selects the two basic voltage ranges and
the polarity of the output signal.
VARIABLE Provides for varying the output amplitude
ontrol within the range selected by the AMPLI 
TUDE switch.
OUTPUT
Connec or
BN connector from which the output is
taken.
TRIGGER
Switch This switch permits the operator to select
the edge of the output pulse at which the
trigger pulse occurs.
onnector BN connector from which the trigger
pulse output is taken.
Firs Time Opera ion
The following procedures are designed to acquaint the
operator with the operation of the Type 114.
1. Set the three VARIABLE controls extreme counterclock 
wise. Set the PERIOD switch to 100 µ S, the WIDTH switch to
SQUARE WAVE, and the AMPLITUDE switch to the " + 1 TO
+3 V" position.
2. onnect the OUTPUT connector of the Type 114 to the
vertical input of an oscilloscope (Tektronix Type 547/1 Al or
equivalent) by means of a 50 ft coaxial cable. Terminate
the coaxial cable at the oscilloscope end with a 50 ft ter 
mination (Tektronix Part No. 011-049 or equivalent). Make
sure the input voltage switch is set to match the voltage of
the power source in use (115 or 230 V ac). See Fig. 2-2. At 
tach the power cord.
3. Apply power to the Type 114 and the oscilloscope. Set
the oscilloscope TIME/DIV or TIME/ M switch to .1 mSE
and obtain a stable display.
4. Set the WIDTH switch to 10 µ S. Turn the associated
VARIABLE control clockwise and note the increase in pulse
width. When the control is turned so that the pulse width
exceeds 100 / j .S, the WIDTH > PERIOD lamp lights.
5. Operate the PERIOD, WIDTH, and AMPLITUDE switches
and controls throughout their ranges and check the results
with the oscilloscope.
Using he Type 114 as a Source of Delayed
Trigger
The use of the Type 114 as a source of delayed trigger
may be demonstrated as follows:
1. Apply a 1 Kpps signal (such as the output of the oscillo 
scope calibrator) through a BN T connector and appro 
priate coax cables to the external trigger input connectors of
2-1

Opera ing Ins ruc ions — Type 114
Fig. 2-1. Fron panel con rol*.
Fig. 2-2. Type 114 rear pon e l.
2-2

Opera ing Ins ruc ions — Type 114
both the Type 114 and the oscilloscope (see Section 1 for
external trigger characteristics required).
2. Obtain an externally triggered sweep on the oscillo 
scope.
3. onnect a coaxial cable between the TRIGGER OUT 
PUT connector of the Type 114 and the vertical input of the
oscilloscope.
4. Turn the Type 114 PERIOD switch to EXTERNAL TRIG 
GER. Set the WIDTH switch to 100 µ S. Turn the WIDTH
variable control to AL. Set the oscilloscope VOLTS/ M
switch to 1 volt. Set the TIME/ M switch to .1 mSE .
5. Set the Type 114 TRIGGER switch to TRAILING EDGE.
A narrow trigger pulse approximately 3 volts in amplitude
should be visible approximately 1 cm from the start of the
oscilloscope trace.
6. Turn the WIDTH — VARIABLE control and note that the
displayed trigger pulse can be delayed from 10 µ sec to more
than 100 µ sec from the start of the trace. By using the 5
basic ranges of the WIDTH switch and by turning the as 
sociated VARIABLE control, it is possible to delay the trigger
pulse over a range from approximately 150 nanoseconds to
10 milliseconds.
Swi ching he Power Transformer Primary Con 
nec ions
A switch on the rear of the Type 114 chassis permits
switching the power transformer connections for operation on
either 94.5-137.5 (115 V ac nominal) or 189-275 volts ac (230
V ac nominal). Be sure the correct fuse is installed.
2-3

NOTES