Data Traces - Stanford Research Systems SR850 User Manual

Screen Display

DATA TRACES

The SR850 collects and displays data in the form
of traces. There are four data traces which may be
defined. Each trace is defined as A•B/C where the
parameters A, B, and C are chosen from X, Y, R,
, Xnoise, Ynoise, Rnoise, Aux Inputs 1-4,
Frequency, and unity (1). C can also be any quan-
tity squared. The traces are defined in the TRACE/
SCAN menu.
Only data traces may be displayed. In order to
display the quantity X, it is necessary to define a
trace to be X and then choose to display that
trace.
When the unit is reset, the traces are defined as
follows:
Trace 1 X
Trace 2 Y
Trace 3 R
Trace 4
where B and C are set to unity in each case.
In most cases, the default trace definitions will suf-
fice. For specialized situations, the traces may be
redefined to fit the experiment. Some examples:
Trace 3 R/AI1 Magnitude/Aux Input 1. This
Trace 4 Xn
Trace 3 AI3
Trace 4 F
4-6
normalizes the magnitude to
an external slowly
signal. (detector output nor-
malized to laser power for
instance.)
Xnoise. The SR850 calculates
the rms noise of X in the band-
width determined by the time
constant.
Aux Input 3. Store and display
the value of Aux Input 3. The
SR850 can monitor an exter-
nal voltage while recording
normal lock-in quantities such
as X, Y, R or .
Frequency. Store the refer-
ence frequency along with the
X, Y, R or .
varying