Circuit Boards - Stanford Research Systems SR850 User Manual

SR850 SERVICE
CAUTION
Potentially lethal voltages are present in this instrument. This unit is to be serviced
by qualified service personnel only. There are no user serviceable parts inside.
Check the LED at the front edge of the power supply board. The unit is safe only if
the LED is OFF. If the LED is ON, then voltages are present within the unit - USE
CAUTION.
Use caution when checking circuits with the power on.
Always disconnect the power cord before replacing or servicing any component
inside the chassis.
CPU Board
DSP Board Analog Input Board
Power Supply Board
CRT Assembly
Disk Drive

CIRCUIT BOARDS

The SR850 has four main printed circuit board assemblies. The four boards shown above contain most of the
active circuitry of the unit. The CRT and video driver circuits are mounted inside the CRT shield assembly.
This assembly is replaced as a unit. The front panel circuit board only has keypad contacts printed on it and
holds no active components. The DSP and Analog boards are cards mounted in a shielded card cage behind
the keypad. The disk drive is mounted on the right hand side panel.
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