Filter
Top Products
POWER BUTTON
The SR850 is turned on by pushing in the power
button. The video display may take a few seconds
to warm up and become visible. Adjust the bright-
ness until the screen is easily readable.The model,
firmware version and serial number of the unit are
displayed when the power is turned on.
A series of internal tests are performed at this
point. Each test is displayed as it is performed and
the results are represented graphically as OK or
NOT OK. The tests are described below.
RAM
This test performs a read/write test to the
processor RAM. In addition, the nonvolatile
backup memory is tested. All instrument
settings are stored in nonvolatile memory
and are retained when the power is turned
off. If the memory check passes, then the
instrument returns to the settings in effect
when the power was last turned off. If there
is a memory error, then the stored settings
are lost and the default settings are used.
ROM
This test checks the processor ROM.
CLR
This test indicates whether the unit is being
reset. To reset the unit, hold down the
backspace [
←
] key while the power is
turned on. The unit will use the default set-
tings. The default setup is listed in a later
chapter.
CLK
This test checks the CMOS clock and cal-
endar for a valid date and time. If the there
is an error, the time will be reset to a default
time. Change the clock settings using the
SYSTEM SETUP menu.
DSP
This test checks the digital signal processor
(DSP).
VIDEO DISPLAY
The monochrome video display is the user inter-
face for data display and front panel programming
operations. The resolution of the display is 640H
by 480V. The brightness is adjusted using the
brightness control knob located at the upper left
corner. As with most video displays, do not set the
brightness higher than necessary. The display
may be adjusted left/right and up/down in the
Screen Settings function in the SYSTEM SETUP
menu.
Power Button
Brightness Control
Soft Keys
Spin Knob
Key Pad
Disk Drive
Front Panel BNC Connectors
Video Display
FRONT PANEL
4-1
W
R S T
M N O
J
G H I
B C A D E F
Y Z
P
U
Q
V X
K L
AUTO
RESERVE
AUTO
GAIN
AUTO
PHASE
AUTO
SCALE
ALT EXP ENTER
0
_
CURSOR
MAX/MIN
.
1 3
CURSOR
SETUP
2
4 6
EDIT
MARK
5
7 9
MARK
8
START
CONT
CURSOR ACTIVE
DISPLAY
PAUSE
RESET
DISK
AUX
OUTPUTS
TRACE
SCAN
GAIN
TC
REF
PHASE
PRINT
SYSTEM
SETUP
MATH
DISPLAY
SCALE
OUTPUT
OFFSET
INPUT
FILTERS
HELP
MODEL SR850 DSP LOCK-IN AMPLIFIER
STANFORD RESEARCH SYSTEMS
SRS
AUTO
SYSTEM
MENU
ENTRY
CONTROL
100M /15pF
1M
REFERENCE IN
SIGNAL IN
SINE OUT
50
OUTPUT
<20mA
CH1 A-ICH2 B
Ω Ω
Ω
LOCAL