Velleman HPS50 Mode D'emploi page 54

Trigger modes
Fig 43
Fig 45
54
Trigger gab - Trigger opening - Niveau de
démarrage - Triggeröffnungsanzeige
Trigger modes :
"norm" = Normal trigger
A triggering (or manual trigger) must occur before
the sample memory is filled. Use this mode when you
want to start displaying the signal when it reaches a
preset threshold value. (Fig 43)
"run" = Auto-trigger mode
The scope automatically triggers if no triggering
occurs for a fixed period of time. This position is used
most frequently and should always be used for mea-
suring DC voltages in particular. (Fig 44)
Fig 44
"once" = Sampling starts after a trigger.
Afterwards, the scope switches to 'HOLD'-mode.
Use this mode to detect e.g. a short, once-only voltage
peak. (Fig 45). Press "memory" repeatedly for a new
triggering.
"roll" = Roll-mode, available for timebases of 1s/div
or slower. Sampling is continuous and the screen
starts rolling as soon as it is full. Use this position for
"recording" slow moving dc signals. (Fig 46)
Fig 46
HPS50 PersonalScope
Notes:
Pressing the Right cursor key generates a manual
•
triggering (except in 'HOLD'-mode)
Changing the trigger mode switches the auto-
•
range mode immediately off.
At time base of 1s/div and slower, the input
•
coupling is DC-only
Normal triggering is the only triggermode for
•
timebases of 1µs/div or faster because of the
oversampling method.
Keep pressing the trigger key during "hold"
•
mode stores the current screen into memory.
When no markers are displayed, the cursorkeys
•
are set for changing the timebase or input sensiti-
vity when no keys are pressed during 10 seconds
TM
.