Vertex Standard VXR-1000 (UHF) Service Manual page 10

Interconnection with Vertex VX- Series Transceivers
VX-3000U
If JP1002 is not jumpered, connect this
line to Pin 8 of Q1043.
If JP1002 is jumpered, connect the
Mobile COR Detect line to JP1002.
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VX-3000L
If JP1016 is not jumpered, connect this
line to Pin 8 of Q1043.
If JP1016 is jumpered, connect the
Mobile COR Detect line to JP1016.