Stanford Research Systems SR860, Руководство по эксплуатации

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Chapter 1 Getting Started 11
SR860 DSP Lock-in Amplifier
converter without overload. In this case the
Input Range should change to 10 mV.
The Input Range is the peak allowable voltage
at the input, whether noise or signal. In this
case, the signal is 5 mVrms or 7 mVpk so
10 mV is the best allowed setting.
The signal strength increases from the
minimum (yellow) to something in the middle.
9. Use the <Amplitude> knob to increase the sine
out to 50.0 mV. The Amplitude is displayed in
the info bar. The peak signal exceeds the input range so the
Input Range
Overload LED
lights. Ovld
indicators also appear on the screen when a
displayed value is invalidated by an input
overload.
10. Press [Auto Range]. During Input Range Overload, the Auto Range
function selects the 1 V range.
Press [Auto Range] again. From the 1 V range, the Auto Range function
changes the Input Range to maximize the signal
at the A/D converter without overload. The
Input Range should change to 100 mV.
10. Press [Input Range Down] to select 30 mV. Settings which have many options, such as
Input Range, Time Constant and Sensitivity, are
changed with up and down keys. The setting is
indicated by LEDs.
The peak signal exceeds the input range so the
Input Range
Overload
LED
lights. Ovld
indicators also appear on the screen when a
displayed value is invalidated by an input
overload.
Press [Input Range Up] to select 100 mV.
11. Press [Sensitivity Down] multiple times to select
50 mV.
The Sensitivity is indicated with 3 LEDs. In this
case, the 5 , ×10 and mV should be lit.
The Sensitivity sets full scale for the bar graphs
and the resolution for the numeric readouts for
X, Y and R. Sensitivity is also the signal
reading corresponding to 10 V on the CH1 and
CH2 outputs (for X, Y and R).
By decreasing the scale value, the bar graphs
and numeric readings display much more
resolution for the smaller signal.
12. Press [Time Constant Down] multiple times to The Time Constant is indicated with 3 LEDs. In