Stanford Research Systems SR844, User Manual

Page: 27 / 246

Outputs, Offsets and Expands 1-17
SR844 RF Lock-In Amplifier
15 Use the
knob
to adjust the offset until the
CH1 display is 0.0 V.
The offset should be about -10%. (R was 0.1 V or
10% of full scale).
Pressing Expand will increase the resolution of the
R measurement. The R offset and expand do not
affect either X or Y. Note that the DVM still reads
10 V for the X output.
16 Press CH1 Offset On/Off again .
This turns off the R offset. The CH1 ROffs
indicator turns off and the displayed R returns to
0.1 V. The
XYOffs
indicator remains on because
XY offsets are still on.
17
Press Display four times to return to
X
display.
The CH1 display returns to showing X with Xoffset
and Expand on.
18 Press Expand twice to turn Expand off. Turn off X expand. The Expand key cycles through
none,
x10 and x100 .
19 Press CH1
Offset On/Off
once
.
Turn off X offset. This also turns off Y offset. The
XYOffs indicators turn off and the displays show
the original measurement of the REF OUT signal.
This completes this exercise. For more information
see Chapter 3,
CH1 Display and Output .