Setup Section - Stanford Research Systems SR124 Operation And Service Manual

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2.3.2.2 Offset
2.3.2.3 Output

2.3.3 Setup section

2.3.3.1 Automatic functions
If the DC output signal is overloaded, the red OVLD indicator (just
above the time constant control) is lit.
The output o set function is enabled and disabled by pressing the
[On O ] button within the OFFSET block. (OFSE, 4 – 14 )
Pressing [Modify] within the OFFSET block switches the focus of the
REFERENCE block to the o set value; turning the REFERENCE
knob will then adjust the o set between 1000% and 1000% of full
scale. (OFST, 4 – 15 )
The overall functional mode of the SR124 is controlled by the [Mode]
button within the OUTPUT block. Pressing [Mode] toggles between
Lock-In and AC Volt modes. (OMOD, 4 – 14 )
The output signal from the SR124 is available on the BNC output
connector within the OUTPUT block. Full scale at the output is
10 V.
The next section of the instrument is "Setup". See Figure 2.5 for
detail.
Four built-in automatic functions are available in this block.
Pressing [Phase] within AUTO starts an auto-phase cycle, which
adjusts the oscillator phase to maximize the output signal. Auto-
phase is disabled when output o set is enabled. (APHS, 4 – 16 )
Pressing [Gain] starts an auto-gain cycle, which will increase the gain
(decrease the sensitivity) step by step to maximize the output without
causing a signal overload. (AGAN, 4 – 16 )
Pressing [O set] starts an auto-o set cycle, which will adjust the
OFFSET setting to null the output signal. Note that the auto-o set
cycle does not change the enabled disabled state for OFFSET. Run-
ning auto-o set with o set disabled will set and report the o set
parameter that would null the output if o set were enabled, but the
output is una ected. (AOFF, 4 – 16 )
Pressing [Lock Assist] starts a measurement cycle for the Reference
oscillator Ext. In, to speed the locking to a user's reference when
operating in external mode. (ASST, 4 – 17 )
Introduction
SR124 Analog Lock-In Amplifier