Reference Section - Stanford Research Systems SR124 Operation And Service Manual

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2.3.3.3 Control inhibit

2.3.4 Reference section

The SR124 user interface controls can be inhibited by setting the
control inhibit switch to the upper position. Note that this is a locking
toggle switch, and must be gently pulled outwards while switching
upwards or downwards.
When in the upper position, the INHIBITED indicator is illuminated
to alert the user that controls and remote commanding are all inhib-
ited.
The next section of the instrument is "Reference". See Figure 2.6 for
detail.
Model SR124 Analog Lock-In Ampli er
REM PHASE
REFERENCE
Quadrant
270 360
Phase
180 270
90 180
0 90
3f
2f External
knob
f
Internal
Rear VCO
Ext. In
TTL
Unlocked
2.0k
200
20
BNC
2.0
0.2
Figure 2.6: The SR124 front panel reference.
The numeric display for the Reference section can show the settings
for phase, reference oscillator frequency, amplitude, DC bias, out-
put o set, and also the save recall slot. This selection is generally
called the "focus" of the interface, and is indicated by one of the
text annunciators at the bottom of the numeric display. For most
FREQ AMPL BIAS OFFSET
Freq Ampl
Mode
Push for
Ext. In TTL
DC Bias
knob
On
On/O
Range (Hz)
210k
21k
Modify
2.1k
knob
210
21
SR124 Analog Lock-In Amplifier
Introduction
kHz V
Hz mV
deg
%
coarse
ne
Push to select
Hold to
null
knob
Ref. Out
Square
Sine
Shape
BNC
50 Ω