R&S ZVA24, Service Manual

Page: 371 / 606

R&S ZVA Repairs
1177.5333.02 3.63 E-11
Replacing a Reflectometer RM24 A510 to 540
(See Chapter 5, Spare Parts List, Items 180, 190, 200 and drawings 1145.1110, 1145.4283)
Opening the instrument and removing the board

Turn off the instrument and disconnect from the mains, screw off the 4 rear-panel feet (460) and
pull off the enclosure (400) backwards.

Remove the bottom instrument cover (297) after undoing the 12 countersunk screws (299).

Remove 3.5mm connection cables (only with option ZVA24-B16)

Disconnect the three cables to the coupler, the LO cable, the two IF cables and the 50-pin control
cable from the reflectometer.

Loosen the captive screws (see 1145.1110.01 sheet 4 / 5) and take out the reflectometer.
Installing the board and reassembling the instrument

Insert the new board into the instrument.

Screw in the captive screws.

Reconnect any cables that have been disconnected.

Fit the 3.5mm connection cables (only with option ZVA24-B16).

Fit the instrument base cover (297) and secure with screws (299).

Slide the enclosure (400) back on and screw the 4 rear-panel feet (460) into position.

Connect the mains cable, turn on at the mains switch and press the ON key.

Select Service Level 2 (see Service Functions).

When the instrument has been started, check the protocol file for errors:
[ INFO : Error Log ]

Record the generator and receiver correction data (see Recording Correction Values ).

Perform the factory system error calibration (see Factory System Error Calibration ).