Anfatec eLockIn 203, Руководство пользователя

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f
m
=
f
Ref
h
Reference Output Phase
[ LockIn / Ref / Phase ] → phase
Phase stands for the phase shift between the periodic excitation provided from the
reference output or, in PLL mode, from the external trigger source and the detected
oscillation at the input.
In case the harmonic
h is equal to one, the number defined here is the phase difference
between the reference output signal and the signal that is multiplied with the lock-in
input. For higher harmonics, the a phase offset Phi is added to the detected signal.
AutoPhase
– an automated phase detection – is implemented. Select the phase
channel and use the
[Measure]
function to set the currently detected phase as
phase offset.
Harmonic
[ LockIn / Ref / Harm ]
This parameter indicates at which harmonic h of the reference frequency we measure.
PLL Input
[ LockIn / Ref / RefIn ]
In order to use an external reference source, the
eLockIn
provides an internal PLL
circuit. This circuit locks onto the external reference. One can switch the reference input
between high signal amplitudes (LV-TTL) and low signal amplitudes (sine wave) with the
switch
RefPLL in
[ Setup / MISC / RefPLL ]
.
This software knob
[RefIn]
switches the PLL
On
or
Off
. In case the reference input is
On , the frequency in the parameter display shows the locking frequency as “PLL:
frequency-value ”. In case the reference input is Off , the frequency value shown in
the parameter display is the frequency of the internal reference.
3.2.3 D
ISPLAY
S
ETTINGS
[ L
OCK
I
N
/ D
ISPLAY
]
In this sub-menu the user can choose which input signal should be displayed on the
front panel. Moreover, the display sensitivity can be adapted separately for each input.
At maximum the device can display four inputs. We refer to them as channels, however,
they can originate from at least 27 different sources:
lock-in output channels – XA, YA, RA,
ϕ
A (signals connected to the lock-in
functionality detected at the n th harmonic) → Group LIA n
lock-in input –
In
(signal taken directly from the front panel input)
→ Group Misc
lock-in settings –
f
(reference frequency of the lock-in amplifier),
Uac
(reference
output amplitude)
→ Group Misc
A/D converter inputs –
AD1
,
AD2, AD3, ... AD8
→ Group ADC
D/A converter inputs – DA1 , DA2, DA3, ... DA8
→ Group DAC
quad-channel-LockIn output channels –
XB, YB, RB, ϕΒ
(if the
eLockIn
has
the internal functionality of two different inputs) or
X1, Y1, R1, j1
(if the eLockIn
has one input only or its input setting is set to Input A, only) – in later case, the
input signal is simultaneously characterized at the first and a higher harmonics.)
→ Group LIA 1
In order to classify this large amount of selections, the channels are organized in the
Group
s:
LIA n
,
Misc
,
ADC, DAC, LIA 1
. The
Group “Off”
stands for “no group” =
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