Keysight 8990B Service Manual page 14

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14
Pull up all the knobs
Remove the screw near the front panel USB ports
Disengage the three tabs
Plastic keyboard cover
Pull the plastic keyboard cover up
Disconnect the cable connected to the front panel
keyboard . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 107
Remove the front panel keyboard from the plastic key-
board cover . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 108
Remove the breakaway board
Disconnect the cable from the back of the breakaway
board . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 110
Remove the Autoprobe board
Remove the two t15 screws
Remove the screws and the cables
Remove the four T10 screws
Replace the backlight inverter board
Replace the touchscreen controller board
Remove the top cover
Cable connections at the BNC connector base
Remove the MMCX cables
Remove the pin cables
Disconnect the semi rigid cable and remove the calibration
cable assembly
Remove the sensor flex and coaxial cables
Remove the SMB cables
Remove the cables from the grommet of the sheet metal
123
Unscrew the screws on the filter board
Remove the sensor adapter board
PCA boards location
Disconnect all the cables
Detach the 8 screws
Remove the mainboard
Remove and replace the power supply module, PC moth-
erboard, and scope acquisition board
Remove and replace the hard disk
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Keysight 8990B Service Guide
. 104
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