This module is an optional component in the Hewlett-Packard 70K Series Modular Measurement System (MMS). It is easiest to quote the Agilent website for an overview:

The Agilent 70310A precision frequency reference, a 1-slot wide plug-in module for the Agilent 70001A mainframe, provides precision reference signals for use by Agilent 70000 systems and other instruments. System frequency accuracy is enhanced because the 10 MHz and 100 MHz reference signals provided by the Agilent 70310A are phase-locked to an internal ovenized oscillator, resulting in excellent stability over both time and temperature. With a highly accurate and stable reference in your system, you can find signals more quickly by tuning to very narrow spans. Option 002 deletes the ovenized oscillator and the accessory power pack from the Agilent 70310A, but retains the external reference input capability. This is a good low cost solution if you plan to connect a house standard or other external reference permanently to your Agilent 70000 modular spectrum analyzer.

HP/Agilent 70310A Features:

Precision 10 MHz and 100 MHz reference signals for use by Agilent 70000 systems and other instruments
Improves reference aging rate, frequency accuracy, and measurement speed

Also, from the HP Installation Manual:

“The HP 70310A Precision Frequency Reference is a 1/8-width module designed to plug into HP 70000 Modular Measurement System mainframes. The HP 70310A module provides 10 MHz and 100 MHz precision reference signals for use by HP 70000 Modular Measurement Systems and other instruments. The HP 70310A functions either by itself, as a separate frequency reference, or as a slave to an HP 70000 Modular Measurement System master element such as the HP 70900A Local Oscillator. When the HP 70310A is configured as a slave, it is controlled by the master element.”

The module is in exceptional cosmetic condition. Serial number is 2922A01667. If desired, we can arrange to have the module calibrated before shipment, either as a stand-alone item, or as part of a complete system. Please contact us to discuss these options.

Location M40 B4

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