Table of Contents
Advertisement
TYPE
1391-5
PULSE, SWEEP, AND TIME-DELAY GENERATOR
Section
1
INTRODUCTION
1.1 PURPOSE.
The Type 1391-B Pulse, Sweep, and Time-De-
lay Generator (Figure 1.1) is a versatile laboratory instrument
designed to generate (1) push-pull pulses, of durations from 0.025
p s e c to 1.1 s e c and a t repetition rates up to 250 kc; (2) linear
sweep voltages of durations from 3 p s e c to 0.12 s e c ; (3) time
delays from 1 p s e c to 1.1 s e c ; and (4) direct and delayed trig-
ger pulses, which can be used independently or to delay the ini-
tiation time of the sweep and main pulse relative to the input
driving signal.
Transition times of the output pulses (0.015
p s e c rise time) are compatible with most present-day oscillo-
scopes. The internal sweep circuit makes possible the use
No.
-
Name
Type
-
1
TRIGGER SELECTOR
4-pos selector switch
of an inexpensive oscilloscope by direct connection to the de-
flection plates.
1.2
DESCRIPTION.
1.2.1 GENERAL. The Type 1391-B is available in either relay-
rack or bench mounting, and is housed in two units. The upper
unit shown in Figure 1.1 is the generator itself, with all oper-
ating controls a t the front panel. Below this unit is the power
supply, with the main POWER switch and pilot light.
1.2.2 CONTROLS. The following table l i s t s the controls on the
front panel of the Type 1391-B Pulse, Sweep, and Time-Delay
Generator (index numbers refer to Figure 1.1):
Function
Selects direction of input-signal zero-crossing to produce di-
-
..
rect synchronizing signal, and provides for a c or dc coupling
of input signal.
2
TRIGGERING LEVEL
Concentric rotary control
Sets dc level a t which input circuits trigger.
TIME DELAY
3
MICROSECONDS
Continuous rotary control
Determines interval between delayed and direct synchronizing
4
RANGE
6-pos selector switch
pulses over the range from 1 p s e c to 1.1 sec.
5
COINCIDENCE GATE
Continuous rotary control
Determines duration of coincidence gate from
3
to 1000
DURATION
psec.
6
COINCIDENCE
Continuous rotary control
Selects threshold a t which coincidence driving signals will
SENSITIVITY
produce delayed sync signals.
7
SWEEP TRIGGER
2-pos toggle switch
Selects either direct or delayed sync signal to start sweep.
PULSE AND SWEEP
TIMING
8
SWEEP MULTIPLIER
5-pos selector switch
Determine sweep duration from
3
to 120,000 p s e c in decimal
9
Sweep Duration
3-pos selector switch
multiples of
3,
6, and 12 p s e c .
Selector
10
VERNIER
Continuous rotary control
Adjusts sweep duration by *lo% from nominal value.
11
PULSE DELAY
6-in. rotary control and dial
Sets duration of pulse.
12
PULSE DURATION
4-in. rotary control and dial
Sets pulse duration.
13
PULSE AMPLITUDE
10-position selector switch
Sets pulse amplitude.
14
OUTPUT IMPEDANCE
5-pos selector switch
Selects any one of five load resistances for pulse current
source.
15
PULSE START
3-pos selector switch
Routes internally produced or externally applied triggering
STOP TRIGGERS
signals to determine pulse duration.
16
RESET SWEEP AND
2-pos spring-return
Provides artificial reset pulse to restore sweep and delay
DELAY
toggle switch
circuit action.
DEFINITIONS:
Terms used in this manual are defined a s fol-
erated within instrument are called gates to distinguish them
lows: DRIVES are input signals used to synchronize the genera-
from the main pulse. Timing signals produced by the delay cir-
tor with external sources. SYNCHRONIZING signals are output
cuit and occurring a t
a
time indicated by the delay control set-
signals from the generator, used to synchronize the external sys-
tings are called DELAYED. Timing signals occurring after start
tem to the generator. TRIGGERS are signals circulating within
of sweep by a time indicated by PULSE DELAY setting are called
the instrument to synchronize the various internal circuits.PULSE
START signals, while those occurring after START by a time indi-
is generally the main output pulse; other rectangular waves gen-
cated by the PULSE DURATION setting are called STOP signals.
Advertisement
Table of Contents
