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With Linac Locking, the above 476MHz LCLS-I Master Oscillator gets replaced by a new RF reference that is phase-locked to the LCLS-II Master Oscillator (located in Sector-2) and transmitted to Sector-10 via an RF-over-Fiber (RFoF) connection.  Lastly, the alignment of the triggers between SC and NC timing is done in Sector-20.

RF Distribution

Linac locking is a portion of the RF distribution network that aims to support LCLS-I timing generation and distribution.  See diagram below for the big picture.

Image Added

(Borrowed from Linac Locking Review slide deck - see References section below)

In the Ej: "MY-JUMP1"

References

Timing for LCLS

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