Keysight Technologies 34959A Service Manual page 107

Troubleshooting and Diagnostics 4
Matrix 1 and Matrix 2 are electrically separate from one another.
Matrix Relays: Armature latching. Analog Bus Relays: Armature non-latching.
For the 34931A, relay part numbers are given on page 138 and the component
locator is shown on page 150. The table below shows the relationship of channel
numbers to relay numbers.
Keysight 34980A Service Guide 107