28
Subject to change without notice
T r i g g e r S y s t e m
100 MHz will improve the noise performance for the trig
-
ger amplifier. This filter removes high frequencies and
is available with AC and DC coupling.
The coupling types low pass and noise reduction
may not be activated simultaneously.
Fig. 6.3: The type B-Trigger
The slope trigger can be coupled with a so called „B Trigger“.
This option is available after pushing TYPE. This function allows
you to adjust the trigger such that first condition „A“ must be met
and then another condition „B“ before the trigger will respond
(refer to Fig. 6.3).
E.g. it is possible to define a
source (channel) and a level of
120 mV on the rising slope of that signal and for the second
condition a level of 80 mV on the falling slope. Additionally, it is
possible to define whether the B event should occur a time (min.
32ns, max. 10s) or a number (min. 1, max. 2
16
) of times after
the A event. The level or time or the number of events can be
entered numerically with the universal knob or in a submenu.
In order to do this first select the setting, then push the soft key
next to
NUMERIC INPUT
. In the window which will open, you can
enter numbers and units with the universal knob or numerical
with KEYPAD button.
6.4 Pulse trigger
The
pulse trigger allows triggering for specific pulse widths of
positive or negative pulses or for pulse width ranges. The oscil
-
loscope triggers if a pulse occurs within the signal selected in
Fig. 6.4: Pulse trigger menu
the SOURCE menu that matches the properties set in the FILTER
menu. If a pulse fulfills the trigger conditions, the oscilloscope
triggers on the trailing slope, i.e. for a positive pulse it triggers
on the falling slope and for a negative pulse on a rising slope.
Activate the
pulse trigger by pressing the TYPE key
31
in the
trigger control panel. Press the FILTER key
36
, then you can
select additional settings for the pulse trigger in the soft menu.
There are 6 different options:
ti ≠ t: The
pulse width ti is unequal to the reference width t.
ti = t: The pulse width ti is equal to the reference width t.
ti
<
t: The pulse width ti is smaller than the reference width t.
ti
>
t: The pulse width ti is greater than the reference width t.
t
1
<
ti
<
t
2
: The
pulse width ti, is smaller than the reference width
t
2
and greater than the reference width t
1
.
not(t
1
<
ti
<
t
2
): The
pulse width ti, is greater than the reference
width t
2
and smaller than the reference width t
1
.
The comparison time can be set anywhere between 8 ns to
134.217 ms. For any value up to 1 ms the resolution is 8 ns
and for any value greater than 1 ms the resolution is 1 µs. The
deviation can be set anywhere between 4ns to 262.144 µs with
a resolution of 4 ns.
Select the desired function and then adjust the desired refer
-
ence time. If you select “t
i
≠ t“ or “t
i
= t“ you can use the soft
menu key TIME and the universal knob in the CURSOR/MENU
control panel to set a reference time. Selecting the soft menu
item
DEVIATION
allows you to use the
universal knob to define
a tolerance zone. Selecting “t
1
<
t
i
<
t
2
“ or “Not(t
1
<
t
i
<
t
2
)“ allows
you to define both reference times with the menu items
TIME 1
and
TIME 2
. Selecting „t
i
<
t“ or „t
i
>
t“ allows you to define
only one limit. Selecting the corresponding soft menu item al
-
lows you to set any of these settings for positively or negatively
polarized pulses. For the associated positive pulse, you define
the width from rising to falling slopes, and accordingly for the
associated negative pulse from falling to rising slopes. As is
consistent with the principle, triggering always occurs on the
second slope of the pulse.
6.5 Logic trigger
You may test all the settings without a logic pro-
be connected, however, the functions will only be
effective with a HO3508 probe connected.
Selecting the logic trigger in the soft menu after pressing the
Fig. 6.5: Logic trigger menu
