Nautel XR12, Руководство по предварительной установке

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XR12 Transmitter Pre-installation Manual Description
Issue 0.17 2005-08-31 Page 1-1
Section 1: Description
This section provides a detailed description of the XR12 transmitter. This section includes the
following topics:
• Capabilities
• Options - see page 1-2
Capabilities
Power
The XR12 Transmitter is capable of RF outputs of 1 - 10 kW.
The operator can vary the power continuously or switch to preset power levels using the XR12’s
graphic user interface (GUI). Presets store the power level, active exciter, and power scheduler status
on a time-of-day and date basis. The operator can configure exciters on a preset for a specific
operating mode (for example, exciter A for conventional AM, and exciter B for IBOC). The power
output can also be scheduled to correspond with authorized daytime power levels.
Modulation
The XR12 lets you use a number of modulation schemes, including:
• double sideband amplitude modulation (AM)
• IBOC (requires additional equipment)
• DRM (requires additional equipment)
Duty cycle
The XR12 will operate at nominal power with a 100% duty cycle (continuously) on an indefinite
basis.
Antenna tolerance
The XR12 will operate at full power even with a VSWR of 1.5:1. A higher VSWR results in a
protective fallback of output power. The greater the VSWR, the greater the reduction in RF power.
(To maintain the quality of digital broadcasts, a maximum VSWR of 1.4:1 is acceptable.)