User's Manual

MODEL 2130 MARKER BEACON
Rev. A April, 2005 1-1
This document contains proprietary information and such information may not be disclosed to others for any
purposes without written permission from SELEX Sistemi Integrati Inc.
1. GENERAL INFORMATION AND REQUIREMENTS
1.1 Introduction
This technical manual contains information required to operate and maintain the Model 2130 Marker Beacon Equipment. It
incorporates the equipment description and specification data, a thorough technical description, complete operating
procedures, operational standards and tolerances, procedures specifying when and how to perform routine and corrective
maintenance, a comprehensive parts list, detailed installation instructions and support schematics and drawings.
1.2 Equipment Description
Refer to Figure 1-1. Marker Beacons are used to provide an aircraft both an aural and visual indication of station passage.
Station identification is provided by both a modulation frequency and keying code. The Marker Beacon transmits an
upward-directed elliptical signal of information at a frequency of 75-MHz. Each Marker Beacon signal is amplitude
modulated by an audio tone which is Morse code keyed. Both the audio tone frequency and the keying are distinctive
according to the marker's location.
Figure 1-1 Marker Beacon
The Marker Beacon is used in two distinct operational environments: en-route or terminal facility. Terminal application
Marker Beacons or, as they are more commonly called, Instrument Landing System (ILS) Marker Beacons, are located
along the extended runway centerline and are used as distance-to-touchdown indicators to indicate significant points
along an instrument approach path. These types are classified as the Outer, Middle, and Inner Marker Beacon systems.
Fan Marker Beacons may also be associated with the ILS to serve as a localizer step down fix or Missed Approach Point
(MAP) for circling approaches to secondary airports.