-
,
--
-c
T
--
_G
•
,
,...,
•..
-
-.-
'0=:.0
.-:-:
•
.~=::=
- =
.-
0
:.0
.-._-
-
-
--
Fig.
55
- Duty cycle is measured by comparing the on-
time to the total time
of
a waveform. Hote that only one
DeNa
position needs to be changed to expand the
DeNa
Sa,.
MelUurlne
dut31 C3/cle
Fig. 54 -
The
DeNa
Time function measures the actual
time
of
the intensified area.
The
vertical or horizontal
verniers
have no effect on the accuracy.
1be
Ii
lUtE
feature may
be
used to
make
the two measurements
needed
to calculate duty cycle
by
changing only one of the Delta
Bar position
controls. Follow the waveforms in Fig.
55
as
you
read the following instructions.
To
determinedutycycle:
4.
Read the time relationship on the digital display.
1. Press the
Ii
Tl~lE
button.
Press
the
4
TIME
butlan.
2.
Adjust the I:-.,.E:"SITY control for the desired contrast
between the Delta
Bar
and
the
background.
3.
Adjust the ABEGIN and
AE~TIcontrols
until the
area
lObe
measured
is intensified.
Delta
Time
measurements
SOTE:
The
microcomputer
Qutomatically
places
the
drcimol
Qnd
sf'lecLS Ike
"1715"
or
"uS"
annunciator.
The
channel
A
aT
B
annunciators
ore
nol
displayed/or
time
measuremenLS b('cause
the
Della
Bar
measures
fhesame
lime
interval
in
bath
channels.
To
measure
any
timerelationship:
TIle Delta Time function
measures
the actual time duration of
the intensified Delta Bar. The time is
measured
with the
same
high accuracy cireuits used
to
measure
frequency. The Delta
Bal minimized interpretation
errors
because the intensified
area
is
part
of
the waveform. eliminating parallax
errors
and
errors
in interpreting a
part
of a CRTdivision.
2.
Adjust the liBEGIN and liEND controls until theon·time
of
thew3\'eform is intensified.
Measurlne
the
delo31
between
twosienals
3.
Read the digital display
and
record the displayed time.
.;.
Adjust the
!l.BEGI~
and liE:\"D control until one full
qcle
cA
the
....
'Sveform is intensified.
S.
Readthe digital display and record the displayed time.
6
Oi\;de
the on-time
by
the total time to determine the duty
c:yde.
For
example.
an
on-time
of
50
uS. and a total time
o(
100
as.
represents a duty
cydeo(
501\.
The Delta
Bar
simplifies measuring time relationships between
two signals because
the
beginning and ending point
are
at
the
same
place
in
both traces.
The
intensified
area
is adjusted to
intensify the
diHerence between a transition
of
the waveform
in
channel A compared
to
the
same
transition
of
the wa\'eform
in
channel
B.
The digital display then shows the time difference of
thet
.....
o points.
To determine
thetimedelay between two signals:
37
To Next Page
Loading...
