Nautel VS1, Troubleshooting Manual

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VS1 Troubleshooting Manual List of terms
Page 7-2 Issue 10.0 2018-10-29
Preset.
A setting that controls power level, frequency and audio parameters. The VS1 allows you to
pre-program multiple presets.
PWB.
Printed Wiring Board.
Shutback.
A complete, but temporary loss of RF output power, caused by any one of a variety of
faults, including high VSWR, high reject load power, RF drive failure, or an open external interlock.
Shutdown.
A complete and permanent loss of RF output power. Typically follows repeated
cutback, foldback or shutback events.
SPI.
Serial Peripheral Interface. A synchronous serial data link standard that operates in full duplex
mode. Devices communicate in master/slave mode where the master device initiates the data frame.
Multiple slave devices are allowed with individual slave select (chip select) lines. Also referred to as a
"four wire" serial bus.
Surge protection panel.
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.