Contents
Keysight N5224A/25A Service Guide 8
7. Repair and Replacement Procedures
Personal Safety Warnings . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7-2
Electrostatic Discharge (ESD) Protection. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7-3
Removal and Replacement Procedures . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7-4
Removing the Covers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7-6
Removing and Replacing the Front Panel Assembly. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7-8
Removing and Replacing the A1–A3 and Other Front Panel Subassemblies. . . . . . . . . . . 7-10
Removing and Replacing the A4–A17 Boards . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7-14
Removing and Replacing the A18 System Motherboard. . . . . . . . . . . . . . . . . . . . . . . . . . . 7-17
Removing and Replacing the A19 Midplane Board . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7-20
Removing and Replacing the A20 Power Supply Assembly . . . . . . . . . . . . . . . . . . . . . . . . 7-22
Removing and Replacing the A21 CPU Board Assembly . . . . . . . . . . . . . . . . . . . . . . . . . . 7-24
Removing and Replacing the A22 GPIB Board . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7-26
Removing and Replacing the A23 Test Set Motherboard . . . . . . . . . . . . . . . . . . . . . . . . . . 7-28
Removing and Replacing the A24 IF Multiplexer Board . . . . . . . . . . . . . . . . . . . . . . . . . . . 7-30
Removing and Replacing the A25 HMA26.5 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7-32
Removing and Replacing the A26 Splitter. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7-34
Removing and Replacing the A27 and A28 Mixer Bricks . . . . . . . . . . . . . . . . . . . . . . . . . . 7-36
Removing and Replacing the A29–A32 Receiver Couplers and Receiver Coupler Mounting
Brackets . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7-38
Removing and Replacing the A33–A36 Test Port Couplers . . . . . . . . . . . . . . . . . . . . . . . . 7-40
Removing and Replacing the A37 Reference Mixer Switch . . . . . . . . . . . . . . . . . . . . . . . . 7-43
Removing and Replacing the A38–A41 Source Attenuators and the A46–A49 Receiver
Attenuators . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7-45
Removing and Replacing the A42–A45 Bias Tees . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7-47
Removing and Replacing the A55 Solid State Drive (SSD) . . . . . . . . . . . . . . . . . . . . . . . . . 7-49
Removing and Replacing the Rear Panel . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7-51
Removing and Replacing the Front Panel LED Boards . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7-53
Removing and Replacing the Fans . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7-55
Removing and Replacing the Lithium Battery . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7-57
Post-Repair Procedures . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7-59