Velleman Personal Scope HPS5, Руководство пользователя

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17
PersonalScope
TM
Trigger functions
The Personal Scope is equipped with a number
of "trigger" aids that are used when the signal can be
displayed on-screen.
Press the
“trig” key
.
The
⇐
(trigger mode) key enables the user to select the
appropriate triggering method, the
⇒
(slope) key is used to
select the trigger slope (see below).
Press the
⇐
key repeatedly to choose between :
“run” mode: The signal will always appear on the
screen, regardless of the level involved. This
position is used most frequently and should always
be used for measuring DC voltages in particular.
“norm” mode: The screen will be adjusted pro-
vided that the signal falls within the trigger level
(interruption in the vertical line on the left-hand
side of your screen). Use this mode when you want
to start displaying the signal when it reaches a
preset threshold value.
“once” mode: The screen is adjusted one single
time , viz. when the trigger level is reached. Use this
mode to detect e.g. a short, once-only voltage peak.
ATTENTION : in the positions 10µs, 4µs and 2µs the unit
will automatically select the ‘norm’ trigger mode. The
trigger level has to be reached for the screen to be adjusted.
F
Both the
⇑
and the
⇓
key remain active in order
to move the signal along the Y-axis, which enables
the user to programme a trigger reference
Repeatedly press the
⇒
key to choose between :
Triggering on the rising slope of the signal. The screen
will only display the signal when a positive slope is
"detected", viz. the signal has to rise in vertical direc-
tion in order to trigger.
Triggering on the falling slope of the signal : The screen
will only display the signal when a negative slope is
"detected", viz. the signal has to drop in vertical direc-
tion in order to trigger.
NOTE : There is a time difference of
±
12µs between the
trigger point (the interruption in the vertical line on the
left-hand side of the screen) and the start of the actual display.
This is specifically true on higher frequencies.
trig
Trigger on rising slope Trigger on falling slope
OPERATION