Slope, positive / Slope, negative
This trigger-mode is intended for special cases of dynamic sig-
nals. It is nearly independent of the actual voltage. Only the
changing of the signal is controlled. If the signal rises or falls
faster than indicated, the trigger is activated. The slope is indi-
cated as Voltage/SampleTime. The voltage specification is in
volt. The sample time is calculated from the quotient
Time/Memory Depth.
dU = U[V]
The controlling of the slope is mainly important for two applica-
tions. To begin with, there is process control in chemistry, biol-
ogy etc. Here, large fluctuations are normal, whereas a sudden
rising indicates an error. Secondly, this mode is suitable to re-
alize a frequency detection.
The MEphisto Scope has a limited measurement range. In order
to prevent uncontrolled fluctuations in the measuring range
near the upper or lower edge, the trigger also triggers if the
current voltage plus the rise would exceed or fall below the
measuring range. When experimentally determining suitable
settings, very small values are recommended as a starting
point. For example, to detect a very short burst of the same
amplitude and a frequency of 1 kHz in a 50 Hz and 10 - 18 V
pp
signal, a trigger value of 0.15625 V is required. The further
away the frequency to be detected is from the fundamental fre-
quency, the safer it can be detected.
dU
U[V]
Memory [Samples]
bzw.
U[V]
=
dU
t
TimeBase
[s]
dt
t
TimeBase
[s]
dt
Memory [Samples]
