Valleylab Force FX-8C, Service Manual

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Right Heat Sink and Component Replacement
Replacement Procedures
Force FX-8C Service Manual 7-21
If you plan to replace one or more components on the existing heat sink,
go to Step 2 – Replace Right Heat Sink Components.
or
If you plan to replace the entire right heat sink assembly, go to
Step 3–Install the Right Heat Sink.
Step 2 – Replace Right Heat Sink Components
Figure 7-5.
Components of the right heat sink
• To replace the damping resistor FET, remove the screw and shoulder
washer that secure it to the heat sink. Position the new damping
resistor FET on the heat sink and reinstall the washer and screw.
• To replace the RF power diode, remove the screw and shoulder washer
that secure the diode to the heat sink. Position the new RF power diode
on the heat sink and reinstall the washer and screw.
• To replace the tank damping resistor, remove the two screws that
secure the top and bottom of the resistor to the heat sink. Position the
new tank damping resistor on the heat sink and reinstall the screws.
• To replace the power MOSFET (under the small circuit board), remove
the four screws that secure the small circuit board to the heat sink. Set
the board and screws aside for reinstallation.
Note the orientation of the power MOSFET. Then, remove the two
screws that secure it to the heat sink. Position the new power MOSFET
on the heat sink and reinstall the two screws.
Position the small circuit board over the power MOSFET and reinstall
the four screws that secure the board to the heat sink.
Power MOSFET
Circuit board
Tank Damping
Resistor
RF Power Diode
Damping Resistor FET