UTD2000M
User
Manual
synchronize
with
the
signal.
Notes:
Under
this
mode,
it
allows
the
occurrence
of
a
rolling
waveform
that
has
no
trigger
signal
at
50ms/div
or
even
slower
time
base.
■
Normal
Trigger:
Under
such
mode,
oscilloscope
captures
a
waveform
only
when
the
trigger
condition
is
satisfied.
The
unit
will
stop
collecting
data
and
waiting
to
be
triggered
when
there
is
no
trigger
signal.
Once
there
is
a
trigger
signal,
it
starts
trigger
scanning.
■
Single
Trigger:
When
the
unit
is
in
this
mode,
it
starts
to
wait
the
trigger
once
the
“Run”
key
is
pressed
by
a
user.
When
the
unit
detects
a
trigger,
it
takes
samples
and
displays
the
waveform
it
has
taken
and
then
stops.
3.
Trigger
Coupling:
it
determines
what
components
of
a
signal
are
being
transmitted
to
trigger
circuit.
Couplings
include
DC,
AC,
low
frequency
reject
and
high
frequency
reject.
■
“DC”
allows
all
components
of
a
signal
to
pass.
■
“AC”
blocks
“DC”
component
and
attenuates
signal
of
less
than
10Hz.
■
“Low
frequency
reject”
blocks
DC
component
and
attenuates
any
low
frequency
component
that
is
less
than
80
KHz.
■
“High
frequency
reject”
attenuates
any
high
frequency
component
that
is
higher
than
80
KHz.
4.
Pre
‐
trigger/Delayed
Trigger:
It
refers
to
the
data
collected
before/after
a
trigger
event.
Normally,
trigger
position
is
set
at
the
horizontal
center
of
a
screen
where
you
can
observe
pre
‐
trigger
and
delayed
trigger
information
up
to
6
div.
There
you
can
adjust
the
horizontal
displacement
by
turning
“POSITION”
knob
(for
horizontal
displacement),
thereby
to
check
more
pre
‐
trigger
information.
By
observing
pre
‐
trigger
data,
users
can
observe
the
waveform
condition
before
trigger,
i.e.
to
capture
the
burrs
produced
at
the
startup
of
a
circuit,
by
observing
and
analyzing
pre
‐
trigger
data,
it
helps
us
to
find
out
the
cause
of
burrs.
2.5
Sampling
System
Settings
As
shown
below,
ACQUIRE
key
located
in
the
control
area
is
the
menu
key
for
sampling
system.
Fig.
2
‐
24
Function
Keys
for
Sampling
System
Once
ACQUIRE
key
is
pressed,
it
pops
out
the
sampling
setting
menu,
which
can
be
used
to
set
the
sampling
mode.
41
