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Board Replacement
R&S ZVB
1145.1078.82 3.36
E-1
Replacing the Bridge unit
(See Chapter 5, Spare Parts List, Item 100 and drawings 1145.1010, 1145.3664)
Opening the instrument and replacing the reflectometer
¾
Turn off the instrument and disconnect from the mains, screw off the 4 rear-panel feet (460) and
pull off the enclosure (400) backwards.
¾
Remove the instrument base cover (297) after undoing the 12 countersunk screws (299).
¾
Remove the 2 screws (176, 177, 178) in the front of the instrument next to the port connector.
¾
Disconnect the source cable, the LO cable, the two IF cables and the 50-pin control cable from the
reflectometer
¾
Remove the 2 screws (151, 156, 161) at the end of the reflectometer and take out the
reflectometer.
Removing the bridge unit
¾
Loosen the MEAS, REF and GEN cables (310, 320, 300) at both ends and disconnect at the bridge
unit.
N.B.:
When loosening support the cable with a 7mm spanner!
¾
Remove the 3 screws (160) and carefully pull the bridge unit off the reflectometer.
¾
Remove the 2 screws (240) and remove the plate (230).
Fitting the new bridge unit
¾
Secure plate (230) to the new bridge unit using the 2 screws (240).
¾
Carefully place the bridge unit on the reflectometer and secure with 3 screws (160).
¾
Screw the MEAS- REF and GEN cables (310, 320, 300) to the bridge unit, and then tighten at both
ends.
N.B.:
When tightening with a 7 mm spanner support the cable.
Reassembling the instrument
¾
Insert the reflectometer into the instrument and reconnect all the cables that have been
disconnected.
N.B.:
Use the lettering on the motherboard as a guide.
¾
Screw in the 2 screws (176, 177, 178) in the front of the instrument next to the port connector.
¾
Screw in the 2 screws (151, 156, 161) in the end of the reflectometer.
¾
Fit the instrument base cover (297) and secure with 12 countersunk screws (299).
¾
Push the enclosure (400) back on and screw the 4 rear-panel feet (460) into position.
¾
Connect the mains cable and turn on at the mains switch. The instrument is now in standby mode
Summary of Contents for ZVB 4
Page 57: ...Instrument Construction and Function Description R S ZVB 1145 1078 82 I 3 2 E 1 ...
Page 133: ...1145 1078 82 5 5 E 1 Spare Parts List Mechanical Drawings ...
Page 142: ...1145 1078 82 5 15 E 1 Block Circuit Diagram ...
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Page 153: ...1145 1078 82 5 17 E 1 Circuit diagrams ...
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