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https://www.lakeshore.com/M81/
MeasureReady™ M81 Synchronous Source Measure System Quick Start Guide
Display
In lock-in mode, the display can be configured to show
either rectangular coordinates (X, Y) or polar coordinates
(R,
θ
). In addition, the % of Range and Frequency are
always displayed. Tap the Action icon in the upper
right hand corner of the display area to change what is
displayed.
X: the real (in phase) component of the detected
signal
Y: the imaginary (quadrature) component of the
detected signal
R: the magnitude of the detected signal
θ:
the phase of the detected signal relative to the
reference signal
% of Range: the amount of the present range
being used by the total input signal, including
any noise
Frequency: the frequency of the reference signal
Reference source
The measure channel will detect frequencies which
are coherent with the specified reference source. For
example, if a sample is being excited with a current by S1,
the reference source can be set to S1.
The reference source can also be set to Ref In. In this
case, the source will track the frequency detected on the
reference input.
Reference harmonic
The reference harmonic can be set to detect signals
at a frequency which is a harmonic of the reference.
For example, if the reference frequency is 1 kHz, setting
reference harmonic to 2 would result in detecting signals
at 2 kHz which are coherent with the reference.
Reference phase shift
The reference phase shift is applied to the reference
source before using the reference for demodulation.
Tap
auto
to set the phase shift to result in zero degrees
of indicated angle. Note that the indication should be
settled before tapping
auto
. Tap
clear
to set the phase
shift to zero.
