Table of Contents
Advertisement
@
T Y P E 1398-A PULSE G E N E R A T O R
(1)
Sine-wave generator.
Capable of 10 kc/s, 0.1 V
into
1 ~ f l
and 2.2Mc/s, 0.5 V into
1 ~ 0 .
Accuracy
* l o % or better. The Type 1330 Bridge Oscillator or
the Type 1001 Standard-Signal Generator may be used.
(2)
Time-markgenerator.
Capable of 100-ms t o 0.1-ps
marks in 5 decade ranges. Accuracy +O.l%or better.
The u s e of a time-mark generator i s optional. When
it i s u s e d , time-measurement accuracy is dependent
upon the accuracy of the time-mark generator (typi-
cally 0.001%) rather than upon the accuracy of the
oscilloscope time-base (typically 3%
).
(3)
Terminated 50-ohm coaxial patch cord.
A coaxial
cable with coaxialfittings on both e n d s with
a
50-ohm
noninductive resistor on one end. An assembly that
c o n s i s t s of a Type 874-R20A Coaxial Patch Cord, a
Type 874-W50 50-ohm Termination, and anadaptor t o
fit the 50-ohm termination to the oscilloscope may
be used. A Type 874-QUP Adaptor f i t s uhf connectors
and a Type 874-QBPA Adaptor f i t s BNC connectors.
A Table of GR874 Connectors is included a t the end
of t h i s book.
(4)
Oscilloscope.
Capable of measuring 5-11s r i s e
times and durations of 1.05
s
t o 75 n s . Accuracy +1%
or better. Must have s w e e p delaying provision if time
jitter .is t o be measured (paragraph 5.8.4).
TIME-MARK
GENERATOR
(optional)
shielded lead
or coaxial cable
\
TIME-MARK
GENERATOR
(optional)
SINE-WAVE
TYPE 1398-A
OSCILLOSCOPE
GENERATOR
PULSE GENERATOR
[
@Terminated
50-ohm coaxial
patch cord or 10-megohm probe.
Figure 5-2.
depending upon measurements
Calibration T e s t Setup.
to be mode
5.8.2
PRF ACCURACY.
Setup.
Connect the -OUTPUT PULSE coaxial
connectors t o the oscilloscope via a terminated 50-ohm
coaxial patch cord. Set the Type 1 3 9 8 4 controls a s
follows:
A F . . . . . . . . . . . . . . . . HIGH (fully clockwise )
PULSE DURATION dial. . . . . . . . . . . . . . . . . .1
PULSE DURATION RANGE.
. . . .
.O.1 t o 1
ps
. . . . . . . . .
AMPLITUDE.
.lo (fully clockwise
)
P R F switch accuracy.
Check or adjust the pulse
repetition frequency a s outlined in Table 5-2. Note
that frequency is measured in terms of period length
(
l/prf
).
T A B L E 5 - 2
)
R
R
A C C U R A C Y
PRF Switch
Period l / p r f
Setting
*5%
Tolerance
300 kc/s
Adjust C117 for period of 3.33
ps.
Vary AF control over full range;
period must change smoothly and
be greater than 10
ps
when AF
control is s e t fully counterclock-
wise.
1.2 Mc/s
Adjust C140 for period of 850 ps.
5.8.3
PULSE DURATION ACCURACY.
Setup.
Connect the -OUTPUT PULSE coaxial
connector t o the oscilloscope via a terminated 50-ohm
coaxial patch cord. Set the Type 1398-A controls a s
follows:
AF
. . . . . . . . . . . . . . . .
.HIGH (fully clockwise
)
AMPLITUDE
. . . . . . . . . .
.10 (fully clockwise
)
P U L S E D U R A T I O N d i a l accuracy. In
e a c h of the
following c h e c k s , s e t the PULSE DURATION d i a l for
the indicated duration a s measured on the oscilloscope
and note the PULSE DURATION d i a l reading:
-u---u-
- I I -
DURATION
PULSE DURATION
Maximum
Set PULSE DUPATION d i a l
R A N G E S e t t i n g
K F
for measured duration o f
1 0 to 100
ps
3 kc/s
50 p s
100
ps
t o 1 ms
300 c / s
500
ps
1 t o 1 0
ps
30 c / s
5 ms
10 t o 100 ms
10 c / s
50 ms
The difference between the lowest and highest
PULSE DURATION d i a l readings i s the error span.
Mechanically position the PULSE DURATION dial
with respect t o i t s associated potentiometer s o that a
reading of 5 l i e s on the center of the error span.
For example: If the lowest d i a l reading was 5.8
and occurred on the 1 0 t o 100ms RANGE and the
Advertisement
Table of Contents
