Advanced Features
Example: divide by N selected with
N=5
ATrig
BT rig
1
000005
A+
N
2
Gate
3
CountNxB
4
------
Independent
5
OOOOOOOns
A
Delay
6
OOOOOOOns
BDelay
7
A Sweep
BSweep
8
Both
the
A
and
B sweep
are
started
after every 5th A Trig-
ger. This
feature
is
useful
where
the
input waveform pro-
duces a
number
of
triggers
but
is repetitive only every
Nth
trigger. A
common
example
of
this sort
of
signal is a video
waveform.
The
example given above, with
N=5,
has
an
input
which
is
repetitive only every five triggers. Setting
N=5
will allow
successive captures
of
the
same
part
of
the
waveform, i.e. it
is phase locked,
but
it
does
not
specify which
part,
or
phase.
This
is
done
with
the
phase
advance
and
retard
buttons,
or
PH+
and
PH-
on
GPIB
and
RS423.
The
phase
advance
and
retard
buttons
are
the
numeric but-
ton
2
and
3 respectively.
These
only work when traces are
being displayed.
They
assume
their
normal
menu
control
functions
at
other
times.
The
input
wave
is
repetitive every five triggers, so it must
be
made
up
of
five phases, all possibly different:
A:B:C:D:E:A:B:C:D:E:
......
etc
If
phase C
is
currently being
captured,
then pressing
the
phase advance
button
will
enable
captures
of
phase
D,
whilst still maintaining
the
phase
lock. Similarly, the phase
retard
button
3
enables
captures
of
phase B in
the
example
above.
Note:
If
'B
delay
by
N'
is selected, 'A
divide
by
N'
cannot
be used,
and
vice-versa.
B Gated by A
This feature
is
shown
on
the
menu
by the letters:
Gate
The
text
is
in line with
the
front panel
button
3. Pressing this
button
selects 'B
gated
by
A',
a further press switches it off
again.
48
Section 2
Example: select B gated by A
ATrig
BT rig
1
:-----.,..Gate
A
-;-
N Disabled 2
In
Independent
Gate
3
CountNxB
4
Independent
5
OOOOOOOns
ADelay
6
OOOOOOOns
BDelay
7
A Sweep
BSweep
8
The
A sweep is unaffected,
and
a
capture
is
initiated by a
valid A trigger after arm.
The
B sweep is still
started
by B
triggers
but
a valid A trigger must
occur
first, i.e.
arm
ATrig
arm
BTrig
ATrig
BTrig
B delayed by N
start
the
car, ..
1re
sequence
A sweep
started
continue
the
capture
sequence
trigger ignored
B trigger gate
is
opened
B sweep
started
This feature
is
shown
on
the
menu
by
the
symbols:
CountNxB
The
text is in line with
the
front
panel
button
4.
If
the func-
tion
is
selected pressing this
button
switches it off.
When
it
is
not selected the first press
of
the
button
selects
'Count
N
x
B',
the last used value is displayed.
The
second press
of
the
button
puts
the
menu
into
number
entry
mode,
see
above.
The
numeric
buttons
are
now used
to
enter
the
number
N. This must
be
in
the
range
1to999999.
In addition, pressing the Trigger
Events
paddle, while in
numeric entry
mode
increases
or
decreases this
number.
Example: delay by N
is
selected with a value
of
20
ATrig BTrig 1
000020
OOOOOOOns
OOOOOOOns
A Sweep
BSweep
A + N Disabled 2
In Indepen.dent
Gate
3
CountNxB
4
Independent
5
ADelay
6
BDelay
7
8
To Next Page
Loading...
