Rohde & Schwarz 1164.4391.03, Service Manual

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R&S FSP Module Replacement
1164.4556.82 3.31 E-1
Replacing the Motherboard A10
( See chapter 5 , spare parts list, item 515, and explosion drawings 1164.4391, 1164.4404. )
The motherboard is fitted from the bottom side.
Opening the Instrument and Removing the Motherboard
Switch off the instrument, pull the mains plug, unscrew the 4 rear-panel feet (450) and push the tube
(410) backwards and take off.
Unscrew the two countersunk screws (260) at the top of the instrument and the three countersunk
screws (250) at the fan side, lift the cover at the top (240) of the instrument to the left side and take off.
Place the instrument on the left side frame and loosen all connecting cables to the boards.
Push out all boards to the top side of the instrument.
Note: The boards can be moved up by pressing carefully from the downside through the
connector wholes in the motherboard against the boards.
Removing the power supply(550).
Unscrew the ten screws (560) at the rear of the power supply.
Pull out the power supply approx. 20 mm towards the rear, slightly tilt towards the bottom and then
pull out completely.
Unscrew the four screws (430) of the front handles on both sides and take off the front handles.
Remove the volume control knob (Option R&S FSP-B3), if present, by pulling it off.
Pull off the labelling panel (270) towards the front.
Unscrew each two countersunk screws (610) in the front frame at the top and at the bottom.
Remove the front panel with keyboard and display (600, 620, 630, 640, 650, 660) to the front and
rotate it to the top of the instrument.
CAUTION
Note the connecting cables are still connected to the controller .
Pull off the connecting cables to the adapter board (LCD, DC/AC illumination converter), keyboard
membrane and spinwheel.
Note: When pulling off the connecting cables be careful with the cable connecting to the keyboard. It is
a film cable which can only be disconnected after sliding up the lock of the film cable plug.
Remove the front module controller (see chapter: Replacing the Front Module Controller A90)
Remove the screws of all motherboard connectors at the rear panel . Unscrew the bolts (530) at the
"COM" and "LPT" ports and (540) aa "Monitor" port. Unscrew the nuts at "Noise Source" and "Ext.
Trig" connectors and the bolts at the "IEC" port.
Note: Do not change the bolts of the “Monitor” and the “LPT” or “COM” !
Pull off the connecting cables at the motherboard (RF attenuator, fan, floppy, Probe/Key, rear panel, ....).
Unscrew five screws with washers in bottom side of the motherboard
Move the motherboard (515) carefully to the front panel (approx. 15 mm) and lift it out of the
instrument to the downside.