
8712ET/ES and 8714ET/ES Assembly Replacement
RF Network Analyzers A5 Receiver Assembly Component Replacement
Service Guide 3-15
Installing the Receiver PC Board.
NOTE If the receiver PC board is being replaced, an installation note may be
included with the replacement board. When an installation note is included
with the PC board, follow the instructions carefully. In some cases, a firmware
upgrade for the network analyzer is required when replacing the receiver PC
board. The installation note will indicate if this is necessary.
1. Inspect the receiver board for damage.
2. Check that the jumper, J17, located toward the back of the board near the rear
connectors, is set correctly (50Ω for standard analyzers or 75Ω for Option 1EC
analyzers).
3. Transfer the attenuator ribbon cable from the old receiver board to the new receiver
board. Plug it into J13.
4. Inspect all the connectors and the semirigid cables on the mainframe for damage.
5. Reverse the procedure used to remove the receiver board from the mainframe.
6. Tighten the semirigid cable connectors to 10 in-lb of torque.
7. Plug the ribbon cable into J1 on the attenuator board.
Removing the Coupler.
1. Loosen, but do not disconnect, the input semirigid cable on the front of the coupler. The
inflexibility of the input cable does not allow much room for movement; removing it
could damage the cable and the input of the coupler.
CAUTION Be careful not to damage the center pins of the semirigid cables. Moving the
cables out of the coupler connector exposes the center conductor pin to
damage.
2. Disconnect the remaining semirigid cables from the coupler. Move the cable ends to the
side of the coupler connectors. These cables are more flexible than the input cables and
can be moved off the coupler connectors.
3. Remove the two screws that attach the coupler to the metal deck. Depending on the
analyzer model, the two screws either go through the body of the coupler or through a
bracket that secures the coupler.
4. Carefully slide the coupler away from the front semirigid cable. Be careful to keep the
connector on the coupler aligned with the end of the cable when separating the two. If
the cable is removed from the coupler at an angle, the center conductor of the coupler
may be bent. (This is particularly important for the 75Ω coupler.) Lift the coupler out of
the assembly.
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