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10
Getting Started
5.
Press the [+90º] key.
Use the <Phase> knob to adjust the phase shift
back to zero (press and hold the <Phase> knob
inward as a short cut). The Phase shift is
displayed in the info bar at the top of the screen.
6.
Touch {Fint} in the info bar.
Touch {1}{0}{kHz} to enter a new frequency.
Use the <Frequency> knob to adjust the
frequency to 1.00000 kHz.
7.
Use the <Amplitude> knob to adjust the sine out
to 5.0 mV. The Amplitude is displayed in the
info bar.
8.
Press [Auto Range].
SR865A DSP Lock-in Amplifier
This adds 90º to the reference phase shift. The
value of X drops to zero and Y becomes minus
the magnitude (−0.5000 V).
The lock-in parameters shown in the info bar,
Phase, Reference Frequency, Detected
Harmonic, Sine Amplitude and Offset, can all
be adjusted from the front panel as well as via a
touchscreen keypad.
Display the numeric entry screen for internal
reference frequency. The 4 buttons labelled
{F1} thru {F4} are frequency presets. Press and
hold them to memorize new frequencies.
Change the frequency to 10 kHz.
The knob is very useful for making small
adjustments or optimizing a setting. Large
changes are better left to the numeric keypad.
The measured signal amplitude X and R should
stay within 1% of 500 mV and Y and θ should
stay close to zero.
As the amplitude is changed, the values of X
and R change to follow.
The yellow LED in the Input Range section
should light. The Input Range is the largest
input signal before overload. The lower the
range, the higher the gain. The signal strength
indicates how much of the A/D converter range
is being used. When the yellow indicator lights,
it means that more gain should be used.
Since the signal has just been reduced by a
factor of 100, the input range should be
adjusted as well.
The Auto Range function changes the Input
Range to maximize the signal at the A/D
Chapter 1
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