Nautel XR6, Operation And Maintenance Manual

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XR6/XR3 Operations and Maintenance Manual List of terms
Page 6-2 Issue 3.1 2013-03-14
Preset.
A setting that controls power level, active exciter, and power scheduler status on a time-of-
day and date basis. Exciters can be configured on a preset for a specific operating mode (for example,
Exciter A - conventional AM, and Exciter B - IBOC). The XR6/XR3 allows you to pre-program up
to six presets.
Shutback.
A complete loss of RF output power, caused by any one of a variety of faults, including
high VSWR, low B+ voltage, high RF current, RF drive failure, external interlock or spark gap.
Surge protection board.
An electrical panel that protects equipment from electrical surges in the
ac power supply, antenna or site ground caused by lightning strikes.
VSWR.
Voltage standing wave ratio. This is an expression of the ratio of forward voltage to reverse
voltage on the feedline and antenna system. An ideal VSWR of 1:1 provides maximum transmitter-
antenna efficiency.