82A04B-60G Phase Reference Module

The Tektronix 82A04B-60G Phase Reference Module extends the capability of the DSA8300 Digital Serial Analyzer sampling oscilloscope by providing extremely low jitter/drift sample position information to the mainframe. This sample position information is based on the phase of a clock the user provides to the 82A04B input.
The Tektronix 82A04B-60G is also compatible with the DSA8200 and TDS/CSA8200 sampling oscilloscopes and can be utilized for a wide variety of design, verification, and manufacturing applications pertaining to IT, telecom, datacom components, and systems operating at 10 Gb/s or quicker.
Here is a comprehensive features list of the Tektronix 82A04B-60G:

Flexible operation:
Triggered
Untriggered (Free-running) Acquisition Without Trigger Signal
Support for enhanced acquisition modes (FrameScan-)
Small module implementation allows:
Acquisition on six other channels
Placement close to the DUT with module extender cable
Fast acquisition rate