Operating Instructions-Type
453/R453
Point A
/
-i
~
/
--r
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L"'
11
1111
I I
11
I I
Vertical
distance
J
__
'
Reference
line
Fig.
2-16.
Measuring
instantaneous
DC
voltage
with
respect
to a
reference.
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.
geflecti?n _ reference signal amplitude
(volts)
o~;~;~~on
- deflection
(divisions)
X
VOLTS/DIV
setting
3.
To
establish an Adjusted Deflection Factor
at
any set-
ting of the
VOLTS/DIV
switch, multiply the
VOLTS/DIV
switch setting by the Deflection Conversion Factor established
in
step
2.
Adjusted
VOLTS/DIV
Deflecti.on
Deflection = tt' X Conversion
Factor se
1
ng
Factor
This
Adjusted Deflection Factor applies only to the channel
used and
is
correct only
if
the
VARIABLE
VOLTS/DIV
con-
trol
is
not moved
from
the position set
in
step
1.
4.
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.
5.
Set the
VOLTS/DIV
switch
to
a setting that
will
provide
sufficient deflection
to
make the measurement.
Do
not
re-
adjust the
VARIABLE
VOLTS/DIV
control.
6.
Measure the vertical deflection
in
divisions and deter-
mine
the amplitude by the following formula:
Signal
Amplitude
Adjusted d
fl
t'
D
fl
.
-v
e ec
ion
- e
ect1on
/'-
(d'
. . )
Factor
1v1s1ons
Example.
Assume
a reference signal amplitude of 30
volts, a
VOLTS/DIV
setting of 5 and a deflection of 4 divi-
sions. Substituting these values
in
the Deflection Conversion
Factor formula (step
2):
Deflection
30
V
Conversion
=
4
X
5
V
= 1
.5
Factor
Then,
with
a
VOLTS/DIV
switch setting of
10,
the Adjusted
Deflection Factor (step
3)
is:
2-22
Adjusted
Deflection
==
10
V X
1.5
==
15
volts/ division
Factor
To
determine the peak-to-peak amplitude of an applied
signal which produces a vertical de.flection of 5 divisions,
use
the Signal Amplitude formula (step
6):
Signal
1
A l
'td
==15VX5==75vots
mp
1 u e
Ti
me-Duration Measurements
To
measure
time
between two points on a waveform,
use
the following procedure.
1.
Connect the signal
to
either
INPUT
connector.
2.
Set the
MODE
switch to display the channel used.
3.
Set the
VOLTS/DIV
switch to display about
five
divi-
sions of the waveform.
4. Set the A Triggering controls
to
obtain a stable display.
5.
Set the
TIME/DIV
switch to the fastest sweep rate that
displays
less
than eight divisions between the time measure-
ment points
(see
Fig.
2-17).
(See
the topic e·ntitled Selecting
Sweep
Rate
in
this
section concerning non-linearity of
first
and last divisions of display.)
6.
Adjust the vertical
POSITION
control
to
move
the points
between
which
the time measurement
is
made to the center
horizontal
line.
7.
Adjust the horizontal
POSITION
control
to
center the
"'
display within the center eight divisions of the graticule.
8.
Measure the horizontal distance betwe·en the
time
measurement points.
Be
sure the A
VARIABLE
control
is
set
to
CAL.
9.
Multiply the distance measured
in
step 8
by
the setting
of the
TIME/DIV
switch. If sweep magnification
is
used,
divide
this
answer
by
10.
Example.
Assume
that the distance between the
time
measurement points
is
5 divisions (see
Fig.
2-17)
and the
TIME/DIV
switch
is
set to
.1
ms
with
the magnifier
off.
Using
the formula:
ho:izontal
TIME/DIV
distance X .
(divisions)
setting
Time
Duration =
magnification
Substituting the given values:
T
. D . 5 X
0.1
ms
1me
urat1on
=
1
The
time
duration
is
0.5 milliseconds.
Frequency Measurements
The
time
measurement technique can also be used
to
,,-
measure the frequency of a signal.
The
frequency of a peri-
odically-recurrent signal
is
the reciprocal of the time dura-
tion of one cycle.
@
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