SRS Labs SR430, Manual

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Math Menu
like the one shown below.
In this example screen, the fit is a line. The curve fit region is delimited by
the two limit markers (heavy dashed vertical lines) as described below.
The final curve fit is plotted between the limit markers along with the
data. The parameters of the fit are displayed at the bottom of the screen.
Each type of fit, line, exponential, or Gaussian, has a different parame-
ters display. The horizontal coordinate is t (in bins or time) and the verti-
cal coordinate is y (in counts).
Line Fit: y = a + b•(t - t
0
)
t
0
= horizontal offset in bins and time units
a = vertical offset in number of counts
b = slope in counts/bin and counts/second
Exp. Fit: y = ae
-(t - t
0
)/b
+ c
t
0
= horizontal offset in bins and time units
a = amplitude in counts
b = time constant in bins and time units
c = vertical offset in counts
Gauss. Fit: y = ae
-(∆t/b)
2
+ c where ∆t = t - t
0
t
0
= peak center position in bins and time units
a = amplitude in counts
b = line width in bins and time units
c = vertical offset in counts
Left and Right Limit
The Left and Right Limit functions set the left and right limits of the fit re-
gion. The default positions of the limits are the the left and right edges of
the graph. To move a limit, move the cursor using the knob or [PEAK]
Press Any Key
to Continue
DONE
Limit:
Return:
y = a + b•(t - t )
SRS
bin 110
Y = 27 cnts 1.126 msec
Type of Fit
View
Left
Right
Limit:
Do Fit:
Params:
Line Exp.
Gauss.
0
t = 33 bins
a = 6.001
b = -5.974026e-001 337.9
µ
sec
5.004 s
-1
0