R&S ZVA8 - Replacing the Bridge Unit (ZVA8 Only)

Repairs R&S ZVA
1177.5333.02 3.62 E-11
Replacing the Bridge Unit (ZVA8 only)
(See Chapter 5, Spare Parts List, drawings 1145.1110, 1145.4177, Item 100)
Opening the instrument and removing the reflectometer
 Remove the Reflectometer (see chapter Replacing Reflectometer Board A510 to A540)
Removing the bridge unit
 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!
 Remove the 3 screws (160) and carefully pull the bridge unit off the reflectometer.
 Remove the 2 screws (240) and remove the plate (230).
Fitting the new bridge unit
 Secure plate (230) to the new bridge unit using the 2 screws (240).
 Carefully place the bridge unit on the reflectometer and secure with 3 screws (160).
 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
 Reinstall the Reflectometer (see chapter Replacing Reflectometer Board A510 to A540)
 Connect the mains cable, turn on at the mains switch and press the ON key.
 Select Service Level 2 (see Service Functions).
 Check the gauge (see Checking the Gauge in chapter 2)
 Record generator and receiver correction data (see Recording Correction Data).
 Perform factory system error calibration (see Factory System Error Calibration).