Stanford Research Systems SR844, User Manual

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Reference Section 3-27
SR844 RF Lock-In Amplifier
Reference Section
The Reference Section of the front panel contains the Reference
Display, connectors for the External Reference Input and for the
Reference Out, and several keys and indicators. The knob is also
located here. The display and keys are discussed below.
Reference
Display The Reference Display is a 4-½ digit LED display that shows the following features:
Key Display Knob Adjust? Description
Phase
Reference Phase Yes The detection phase relative to
the reference (deg).
Freq Reference
Frequency Only in Internal
Reference Mode The detection frequency.
PRECISE
FREQ
Precise
Reference
Frequency Only in Internal
Reference Mode Displays the reference
frequency on the Channel 2
and Reference Displays with
extra precision.
I.F. IF Frequency Only in Internal
Reference Mode The IF (chop frequency) used
in the SR844, provided for
information.
AuxOut AUX OUT 1, 2 Yes The rear panel Aux Output
voltages.
CH1/CH2
Offset Modify
Offset Yes The offset (% f.s.) for the CH1
or CH2 display quantity.
SETTLE... Elapsed Time No Time constants elapsed.
Scan Set Scan Start Yes The start frequency for manual
scanning.
Note 1
Scan Set
Scan Stop Yes The stop frequency for manual
scanning.
Note 1
Scan Set Scan Steps Yes The number of frequency steps
for manual scanning.
Note 1
Note 1 See the description of Scan and Rel later in this chapter for more details.