DVOR Ant. Manual 570002-0001G PDF

\ THIS DOCUMENT CONTAINS PROPRIETARY INFORMATION AND SUCH INFORMATION MAY NOT BE DISCLOSED TO OTHERS FOR ANY PURPOSES WITHOUT WRITTEN PERMISSION FROM SELEX ES INC. Copyright © 2014, Selex ES Inc. Operations and Maintenance Man...

\ THIS DOCUMENT CONTAINS PROPRIETARY INFORMATION AND SUCH INFORMATION MAY NOT BE DISCLOSED TO OTHERS FOR ANY PURPOSES WITHOUT WRITTEN PERMISSION FROM SELEX ES INC. Copyright © 2014, Selex ES Inc. Operations and Maintenance Manual Model 1150 Doppler VOR ( DVOR) Antenna 570002-0001 Rev. G July, 2018 Selex ES Inc. 11300 West 89th Street Overland Park, KS U.S.A. 66214 THIS SHEET INTENTIONALLY BLANK  SAFETY SUMMARY The following are general safety precautions that are unrelated to specific procedures and therefore do not appear elsewhere in this publication. These are recommended precautions that personnel should understand and apply during through the many phases of operation and maintenance. ELECTROSTATIC SENSITIVE DEVICES PRECAUTIONS Since most modules used in all models of equipment have Electrostatic Discharge (ESD) sensitive devices included in them, all modules should be considered sensitive to electrostatic discharge. Handling in the field shall be the same as in the factory. Each system is shipped with a wrist strap that must be worn while maintaining the equipment. The wrist strap shall be fastened to the equipment chassis either in the designated plug-in or attached to the equipment chassis with the alligator clip. The wrist strap must be used before any modules are removed from the equipment and at all times while handling the modules until they are placed in a protective environment such as an anti-static bag. Modules or boards must not be placed on any non-conducting surface such as wooden work benches, painted metal work benches, plastics, or technical manuals. Any work surface to be used must have a conducting mat placed on it and attached to earth ground. The mat and additional wrist straps can be obtained from Selex ES Inc. KEEP AWAY FROM LIVE CIRCUITS Operating personnel must at all times observe all safety regulations. Under no circumstances should any person remove any protective covers that expose lethal voltages. Do not replace components or make adjustments inside the equipment with primary power supply turned on. Under certain conditions, dangerous potentials may exist when the power is in the off position, due to charges retained by capacitors. To avoid casualties, always remove power and allow time for the capacitors to discharge before touching it. DO NOT SERVICE OR ADJUST ALONE Under no circumstances should any person reach into or enter the enclosure for the purpose of servicing or adjusting the equipment except in the presence of someone who is capable of rendering aid. RESUSCITATION Personnel working with or near high voltages should be familiar with modern methods of resuscitation. THIS SHEET INTENTIONALLY BLANK  Selex ES Inc. This equipment is supplied by Selex ES Inc. For replacement parts and repair service, contact Selex ES Inc. using the contact information provided below. HOW TO ORDER REPLACEMENT PARTS When ordering replacement parts, you should contact Selex ES Inc. by fax, phone or email. Please address the following items (as applicable) in your correspondence to enable us to provide the best possible service. 1. Selex ES Inc. model number, type and serial number of equipment. 2. Unit sub-assembly number (where applicable). 3. Item or reference symbol number from parts list or schematic. 4. Selex ES Inc. part number and description. 5. Manufacturer’s code, name and part number (where applicable). 6. Quantity of each replacement part required. HOW TO REQUEST REPAIR SERVICE In order to ensure prompt attention, parts returned for repair should have the following: 1. RMA number (Return Material Authorization number), assigned prior to return when requesting repair service. 2. Unit part number 3. Site location 4. System information 5. Ship-to address for return 6. Contact name and number 7. Date and time of request CONTACT INFORMATION Selex ES Inc. 11300 W 89th Street Overland Park KS, 66214, USA Main Switchboard: (913) 495-2600 Main Fax: (913) 492-0870 Toll free: (800) 331-2744 CSM Direct Phone: (913) 495-2625 CSM E-mail: [email protected] World Wide Web URL: www.us.selex-es.com THIS SHEET INTENTIONALLY BLANK  MODEL 1150 DVOR ANTENNA TABLE OF CONTENTS Paragraph Description Page # 1. GENERAL INFORMATION AND REQUIREMENTS...............................................................1-1 1.1 Introduction....................................................................................................................................1-1 1.2 Equipment Description...................................................................................................................1-1 1.2.1 Carrier Antenna............................................................................................................................. 1-2 1.2.2 Sideband Antenna (Version 1)...................................................................................................... 1-3 1.2.3 Sideband Antenna (Version 2)...................................................................................................... 1-4 1.2.4 Tuning Stub (used with 030510-0004 only).................................................................................. 1-5 1.2.5 Positioning Piece (used with 030510-0004 only).......................................................................... 1-5 1.2.6 Balun (used with 030510-0004 only)............................................................................................ 1-5 1.2.7 Pedestal......................................................................................................................................... 1-5 1.2.8 Radome......................................................................................................................................... 1-5 1.2.9 Counterpoise................................................................................................................................. 1-5 1.2.10 Field Monitor Antenna.................................................................................................................. 1-5 1.3 Equipment Specification Data........................................................................................................1-7 1.4 Equipment Supplied.......................................................................................................................1-8 1.5 Equipment Required but not Supplied...........................................................................................1-8 1.6 Optional Equipment.......................................................................................................................1-8 2. TECHNICAL DESCRIPTION......................................................................................................2-1 2.1 Introduction....................................................................................................................................2-1 2.2 Simplified Theory of Operation.....................................................................................................2-1 2.2.1 Sideband Antenna Tuning (PN 030510-0002).............................................................................. 2-1 2.2.2 Sideband Antenna Tuning (PN 030855-0001).............................................................................. 2-2 2.3 Detailed Theory of Operation........................................................................................................2-3 3. OPERATION.................................................................................................................................3-1 3.1 Introduction....................................................................................................................................3-1 4. STANDARDS AND TOLERANCES............................................................................................4-1 4.1 Introduction....................................................................................................................................4-1 5. PERIODIC MAINTENANCE.......................................................................................................5-1 5.1 Introduction....................................................................................................................................5-1 5.2 Performance Checks.......................................................................................................................5-1 5.3 Other Onsite Maintenance..............................................................................................................5-1 5.4 Offsite Maintenance.......................................................................................................................5-1 6. MAINTENANCE PROCEDURES................................................................................................6-1 6.1 Introduction....................................................................................................................................6-1 6.2 Performance Check Procedures.....................................................................................................6-1 6.3 Other Maintenance Procedures......................................................................................................6-1 6.3.1 Site Inspection............................................................................................................................... 6-1 6.3.2 Inspection of the Antenna System................................................................................................. 6-1 6.3.3 Inspection of Field Monitor Antenna............................................................................................ 6-1 6.4 Special Maintenance Procedures....................................................................................................6-1 7. CORRECTIVE MAINTENANCE.................................................................................................7-1 7.1 Introduction....................................................................................................................................7-1 8. PARTS LIST..................................................................................................................................8-1 8.1 Introduction....................................................................................................................................8-1 9. INSTALLATION, INTEGRATIONS AND CHECKOUT...........................................................9-1 9.1 Introduction....................................................................................................................................9-1 9.2 Unpacking and Repacking..............................................................................................................9-1 9.3 Test Equipment Required...............................................................................................................9-1 Rev. G July, 2018 i This document contains proprietary information and such information may not be disclosed to others for any purposes without written permission from Selex ES Inc. MODEL 1150 DVOR ANTENNA TABLE OF CONTENTS (cont.) Paragraph Description Page # 9.4 Installation......................................................................................................................................9-1 9.4.1 Sideband Antenna Installation....................................................................................................... 9-1 9.4.2 Theodolite Method........................................................................................................................ 9-2 9.4.3 Tape Measure and Spirit Level Method........................................................................................ 9-4 9.4.4 Carrier Antenna Installation.......................................................................................................... 9-6 9.4.5 Cutting a Replacement Antenna Feed Cables to Proper Electrical Length................................... 9-6 9.4.6 Tuning the Sideband Antennas (PN 030510-0002)....................................................................... 9-8 9.4.7 Tuning the Sideband Antennas (PN 030814-0001with Tuning CCA).......................................... 9-9 9.4.8 Tuning the Carrier Antenna......................................................................................................... 9-10 9.4.9 Checking Phase Length of Sideband Antennas Using the Carrier Antenna................................ 9-10 9.4.10 Field Monitor Antenna Foundation Installation.......................................................................... 9-11 9.4.11 Field Monitor Antenna (470178-0002) Installation.................................................................... 9-12 10. SOFTWARE................................................................................................................................10-1 10.1 Introduction..................................................................................................................................10-1 11. TROUBLESHOOTING SUPPORT DATA................................................................................11-1 11.1 Introduction..................................................................................................................................11-1 ii Rev. G July, 2018 This document contains proprietary information and such information may not be disclosed to others for any purposes without written permission from Selex ES Inc.  MODEL 1150 DVOR ANTENNA LIST OF FIGURES Figure # Description Page # Figure 1-1 Typical DVOR Site....................................................................................................................... 1-1 Figure 1-2 Carrier Antenna............................................................................................................................. 1-2 Figure 1-3 Sideband Antenna PN 030510-0004 (Version 1).......................................................................... 1-3 Figure 1-4 Sideband Antenna PN 030855-0001 (Version 2).......................................................................... 1-4 Figure 1-5 DVOR Field Monitor Dipole Antenna.......................................................................................... 1-6 Figure 1-6 DVOR Counterpoise Edge Monitor Dipole Antenna.................................................................... 1-7 Figure 2-1 Alford Loop Matching Network CCA........................................................................................... 2-2 Figure 2-2 Approximate Current Distribution for Each Element of the Alford Loop Radiator...................... 2-2 Figure 2-3 Alford Loop Antenna Current Directions in One of the Four Half-Wave Elements..................... 2-3 Figure 2-4 Generation of Azimuth-Dependent FM by a DVOR Station......................................................... 2-4 Figure 2-5 Phase Relationship of DVOR Course Forming Signals................................................................ 2-5 Figure 2-6 Instantaneous Direction of an RF Source with Respect to Aircraft Receivers A, B, C and D....... 2-6 Figure 2-7 Received and Detected AM and FM Signals by Aircraft Receivers A, B, C, and D..................... 2-7 Figure 2-8 Doppler Shift (Wave Front Measurement).................................................................................... 2-7 Figure 2-9 Doppler Shift (Heterodyning)....................................................................................................... 2-8 Figure 9-1 Antenna Spacing on Counterpoise Mounting Rail Using Theodolite............................................ 9-2 Figure 9-2 Antenna Placement on the Counterpoise....................................................................................... 9-3 Figure 9-3 Antenna Spacing on Counterpoise Mounting Rail Using Sight and Measurement....................... 9-5 Figure 9-4 RF Connector Assembly Diagram................................................................................................. 9-7 Figure 9-5 Diagram of Feed Cable, Tuning Stub, Tee Connector and Positioning Piece Connections.......... 9-8 Figure 9-6 Alford Loop Matching Network CCA......................................................................................... 9-10 Figure 9-7 Typical DVOR Field Monitor Antenna Foundation Installation................................................. 9-11 Figure 9-8 DVOR Field Monitor Antenna and Tower (Part No. 470178-0002) Parts Location Diagram.... 9-12 Figure 11-1 Model 1150 DVOR Antenna Family Tree.................................................................................. 11-2 Rev. G July, 2018 iii This document contains proprietary information and such information may not be disclosed to others for any purposes without written permission from Selex ES Inc. MODEL 1150 DVOR ANTENNA LIST OF TABLES Table # Description Page # Table 1-1 Equipment Specification Data....................................................................................................... 1-7 Table 1-2 Equipment Supplied...................................................................................................................... 1-8 Table 1-3 Equipment Required But Not Supplied......................................................................................... 1-8 Table 1-4 Optional Equipment...................................................................................................................... 1-8 Table 2-1 Positioning Piece Part Number and Length for DVOR Frequencies............................................. 2-2 Table 2-2 Doppler Shift Values from Heterodyning..................................................................................... 2-8 Table 5-1 Onsite Maintenance....................................................................................................................... 5-1 Table 5-2 Other Onsite Maintenance............................................................................................................. 5-1 Table 8-1 Doppler Antenna Kit (48 Antenna) (470165-0003)...................................................................... 8-1 Table 8-2 Doppler Antenna Kit (48 Antenna) (470165-0004)...................................................................... 8-2 Table 8-3 Stand Alone DVOR Carrier Antenna Kit (470209-0001)............................................................. 8-3 Table 8-4 Carrier Antenna Kit with Walk-in Radome (470208-0001).......................................................... 8-4 Table 8-5 Civil Installation Kit Rohn Antenna (470252-0001)..................................................................... 8-4 Table 8-6 Doppler Field Monitor Kit (470178-0002)................................................................................... 8-4 Table 9-1 Equipment Required for Installation but not Supplied.................................................................. 9-1 Table 11-1 Schematic and Installation Drawings.......................................................................................... 11-1 iv Rev. G July, 2018 This document contains proprietary information and such information may not be disclosed to others for any purposes without written permission from Selex ES Inc.  MODEL 1150 DVOR ANTENNA 1. GENERAL INFORMATION AND REQUIREMENTS 1.1 Introduction This technical instructional book contains data required to install, operate, and maintain the DVOR mechanical Alford loop antenna, supplied by Selex ES Inc., Overland Park, Kansas. Included are a general description and specification data, technical description, operating procedures, standards and tolerances, periodic and corrective maintenance instructions, parts list, installation instructions, and troubleshooting support data. This section contains an equipment description, including purpose of the equipment, accessories supplied, and equipment required but not supplied. 1.2 Equipment Description Figure 1-1 shows a typical DVOR site. The DVOR antenna system consists of a single carrier antenna assembly at the center of the counterpoise, and 48 sideband antenna assemblies spaced equally in a 44 foot diameter circle concentric with the carrier antenna assembly. The mechanical Alford loop antenna is constructed of two fixed-length dipole antennas, folded and arranged so that the element midsections form a square approximately 1/4 wavelength on each side. The carrier and sideband antennas consist of a single Alford loop, mounted on a support plate. The support plate is mounted 48 inches (approximately one-half wavelength) above the counterpoise by metal pedestal. This is to insure the proper coverage of the signal in-space. The pedestal provides a conduit for RF cables. Each antenna element is enclosed in a weatherproof, cone-shaped fiberglass radome. Figure 1-1 Typical DVOR Site The antennas are mounted on a counterpoise. The counterpoise is a circular, metallic support structure that is made of aluminum or galvanized steel and is assembled in segments that are bolted together. The counterpoise is between 60 and 120 feet in diameter and is elevated between 8 to 20 feet above ground level. Rev. G July, 2018 1-1 This document contains proprietary information and such information may not be disclosed to others for any purposes without written permission from Selex ES Inc. MODEL 1150 DVOR ANTENNA 1.2.1 Carrier Antenna Refer to Figure 1-2. The carrier antenna is a single Alford loop on a support plate. The antenna is supported above the counterpoise by a metal pedestal. This antenna is electrically tuned to the station frequency by means of two large, air-dielectric, metal disc capacitors. Figure 1-2 Carrier Antenna 1-2 Rev. G July, 2018 This document contains proprietary information and such information may not be disclosed to others for any purposes without written permission from Selex ES Inc.  MODEL 1150 DVOR ANTENNA 1.2.2 Sideband Antenna (Version 1) Refer to Figure 1-3. Each sideband antenna (part number 030510-0004) is an Alford loop, similar to carrier antenna but, without the large hole in the center of the support plate. This antenna is electrically tuned to the station frequency by means of single, high voltage, glass capacitor. The antennas are mounted independently on individual support plates, supported above the counterpoise by metal pedestals equal in height to the carrier antenna. Figure 1-3 Sideband Antenna PN 030510-0004 (Version 1) Rev. G July, 2018 1-3 This document contains proprietary information and such information may not be disclosed to others for any purposes without written permission from Selex ES Inc. MODEL 1150 DVOR ANTENNA 1.2.3 Sideband Antenna (Version 2) Refer to Figure 1-4. The sideband antenna (part number 030855-0001) is electrically identical to sideband antenna Version 1. The Version 2 antenna provides improved tuning using a printed circuit board. This antenna entered production in the year 2010. The glass capacitor, along with the balun cable, feed cable and stub have been replaced by a printed circuit board assembly. This greatly improves tuning and eliminates cables and connectors. All tuning can be accomplished from outside the antenna with the radome installed. Mounting is identical to version 1. Figure 1-4 Sideband Antenna PN 030855-0001 (Version 2) 1-4 Rev. G July, 2018 This document contains proprietary information and such information may not be disclosed to others for any purposes without written permission from Selex ES Inc.  MODEL 1150 DVOR ANTENNA 1.2.4 Tuning Stub (used with 030510-0004 only) The tuning stub is a 90° line section made out of RG-214 cable with a connector on one end and open at the other end. The basic function of the stub is to supply the needed capacitive reactance to make the point of the stub attachment pure resistive. 1.2.5 Positioning Piece (used with 030510-0004 only) The positioning piece is a length of RG-214 cable with a connector at each end. The purpose of the positioning piece is to place the tuning stub at a point on the input line where the resistive component of the complex impedance is equal to the characteristic impedance of the line (50 ohms). The length of the positioning piece is factory selected for the frequency band of operation. Refer to Table 2-1 for part number and length. 1.2.6 Balun (used with 030510-0004 only) The balun is a 180° line section that hangs directly under the center of the antenna inside the pedestal and is used to develop a balanced signal output from a coaxial line input. 1.2.7 Pedestal The antenna pedestal is an aluminum tube with mounting plates on each end. The pedestal supports the Alford loop antenna and provides a conduit for feed cables. 1.2.8 Radome The radome is a cone-shaped, fiberglass enclosure that protects the radiating elements of the antenna from the weather and vermin infestation. 1.2.9 Counterpoise The counterpoise is a circular, metallic support structure that is made of aluminum or galvanized steel and is assembled in segments that are bolted together. It is typically between 60 and 120 feet in diameter and is normally elevated 8 to 20 feet above ground level. 1.2.10 Field Monitor Antenna Refer to Figure 1-5. There is one field monitor antenna in each DVOR system provided as standard equipment. The field monitor antenna is a single Dipole antenna that is installed on a support tower 300 to 600 feet from the carrier antenna. A second optional antenna can be provided. Typically, the field monitor antenna is located on an important radial (such as an approach radial) and may be located on any radial. Figure 1-6 depicts a Counterpoise edge mounted DVOR monitor antenna available for the Model 1150A DVOR. This antenna may be used alone or with the antenna in Figure 1-5 to monitor the performance of the DVOR transmitter. Rev. G July, 2018 1-5 This document contains proprietary information and such information may not be disclosed to others for any purposes without written permission from Selex ES Inc. MODEL 1150 DVOR ANTENNA Figure 1-5 DVOR Field Monitor Dipole Antenna 1-6 Rev. G July, 2018 This document contains proprietary information and such information may not be disclosed to others for any purposes without written permission from Selex ES Inc.  MODEL 1150 DVOR ANTENNA Figure 1-6 DVOR Counterpoise Edge Monitor Dipole Antenna 1.3 Equipment Specification Data The equipment specification data is listed in Table 1-1. Table 1-1 Equipment Specification Data Equipment Manufacturer Selex ES Inc. Equipment Model and Type DVOR Antenna Frequency Range 108-118 MHz Polarization Horizontal Characteristic Impedance of Feed Cables 50 ohm Environmental Temperature Range -50°C to +70°C Relative Humidity 0 to 95% non-condensing Cone of Silence 37.5 to 42.5 degrees from vertical Rev. G July, 2018 1-7 This document contains proprietary information and such information may not be disclosed to others for any purposes without written permission from Selex ES Inc. MODEL 1150 DVOR ANTENNA 1.4 Equipment Supplied Table 1-2 is a list of all major equipment supplied. Table 1-2 Equipment Supplied Quantity Description Part Number 1 Doppler Antenna Kit (48 Antenna) 470165-0003 OR Doppler Antenna Kit (48 Antenna) 470165-0004 1 Civil Installation Kit Rohn Antenna 470252-0001 1.5 Equipment Required but not Supplied Table 1-3 is a list of all equipment that is not supplied, but is required to make the antenna operational, or to install the antenna. Table 1-3 Equipment Required But Not Supplied Quantity Description Manufacturer Part # 1 Network Analyzer, Anritsu Model MS2026A Network Analyzer, Agilent Model 8712ET 1 Multimeter, Fluke Model 83 2 50 Ohm Terminations, Type N Bird 1.6 Optional Equipment Table 1-4 contains a list of the optional equipment for the DVOR Antenna system. Table 1-4 Optional Equipment Quantity Description Part Number 1 Stand Alone DVOR Carrier Antenna Kit 470209-0001 1 Carrier Antenna Kit with Walk-in Radome 470208-0001 (for extreme wind environments) 1 Doppler Field Monitor Kit (at 100 meters) 470178-0002 1 DVOR Counterpoise Edge Monitor Kit 470455-0001 1-8 Rev. G July, 2018 This document contains proprietary information and such information may not be disclosed to others for any purposes without written permission from Selex ES Inc.  MODEL 1150 DVOR ANTENNA 2. TECHNICAL DESCRIPTION 2.1 Introduction This section contains a simplified theory of operation of the Alford loop antenna and a detailed theory of operation of the DVOR antenna system. 2.2 Simplified Theory of Operation The Alford loop antenna emits a horizontally polarized wave. The horizontal radiation pattern, in free space, from a single horizontally polarized Alford loop is omni-directional and the vertical pattern is bi-directional. Each dipole has a wide radiating surface making the Alford loop antenna more efficient than other loop type antennas with smaller radiating surfaces. A signal with opposite phases is applied to the center of the dipoles via a crossover connection (balun). This causes the currents in the folded-back portions of the elements to contribute very little to the radiated field, since the currents are in opposite directions and tend to cancel each other. This also causes the current flow in the radiating faces of the loop to be in the same direction, either clockwise or counter-clockwise depending on the point in the RF cycle. Each radiating face, being the midsection of a 1/2 wavelength element (approximately), has a current amplitude that varies from a maximum at the center of the radiating surface to approximately 70 percent of maximum at the ends of the radiating surface, refer to Figure 2-2. The slight non-uniformity of current amplitude does not destroy the circularity of the pattern because, at points oriented near the corners of the loop, such as point P in Figure 2-3, some radiation is also received from an adjacent face. Consequently, the loop behaves as if the current were nearly constant in all portions of the radiating faces and the radiating pattern is approximately the same as that of a small circular loop. The Alford loop is generally mounted so that the loop is contained in a plane parallel to the ground. It has a non-directional horizontal radiation pattern and a figure-of-eight vertical radiation pattern. The two dipoles attached with a crossover require a balanced feed. This is accomplished by attaching a half wave- length balun between the two feed points. The purpose of the half-wave-length balun is to develop the equivalent of a balanced signal source output from a coaxial line input, which is inherently unbalanced. With a balun in place, either feed point can be fed with an unbalanced line. For the 030855-0001 antenna the balun function is accomplished with a transformer. The two outputs are 180 degrees opposed and feed the antenna elements. In theory, the unbalanced feed point impedance is 300 ohms resistive at the resonant frequency and the impedance departs from 300 ohms as frequency varies across the VOR band. This variation is sufficient to cause a substantial mismatch to the transmitter at this point when not tuned correctly. For this reason, an impedance matching network is required. 2.2.1 Sideband Antenna Tuning (PN 030510-0002) Inside the Alford loop antenna is a glass or an air-dielectric metal disc tuning capacitor (depending on the antenna). The tuning capacitor is located in the center of the dipoles near the feed point. The tuning capacitor does not change the resonant frequency of the antenna, but does affect the impedance match of the antenna. The input impedance of the Alford loop antenna was measured over the 108 MHz to 118 MHz VOR band while varying the tuning capacitors from maximum to minimum capacitance. The results, plotted on a Smith Chart, showed the tuning capacitor to have the same effect on impedance as frequency variation. In addition, the impedance plot was a circle centered on an impedance of 50 ohms resistance in parallel with 30 ohm inductance. To match the antenna, the antenna input impedance must be 50 ohms at the operating frequency. The simplest means to match the antenna is to select a point on the input coax where the impedance equals 50 ohms resistive in parallel with some value of reactance. At that point, a reactive stub (tuning stub) is inserted between the RF cable and the antenna connector. This is accomplished by using a positioning piece and type N Tee connector. The tuning stub is then trimmed to tune out the reactance, yielding a matched 50 ohm impedance to the transmitter. Rev. G July, 2018 2-1 This document contains proprietary information and such information may not be disclosed to others for any purposes without written permission from Selex ES Inc. MODEL 1150 DVOR ANTENNA The tuning stub length has a profound effect on the VSWR. It is cut for minimum VSWR at one frequency. The tuning capacitor is then used to impedance match the antenna for a better than 1.10:1 VSWR. The proper match cannot be obtained over the full 10 MHz operating bandwidth with one positioning piece length between the antenna input and the type N Tee. Therefore, the positioning piece is factory selected for the band of operation (see Table 2-1). Table 2-1 Positioning Piece Part Number and Length for DVOR Frequencies Frequency Part Number Length 108 - 110 MHz 070350-0001 16.75" 111 - 114 MHz 070350-0002 12.0" 115 - 118 MHz 070350-0003 8.75" 2.2.2 Sideband Antenna Tuning (PN 030855-0001) Refer to Figure 2-1. Inside the Alford loop antenna is a printed circuit board with two tuning capacitors facing the bottom of the antenna. To match the antenna, the two tuning capacitors are used to set the resonant frequency and to minimize the return loss (improve the VSWR) at the operating frequency of the VOR. A wire link (E1) in the antenna is cut during the installation when used at 114 MHz and higher. Capacitor C3 is adjusted to the operating frequency and C5 is tuned for the best return loss (VSWR). Transformer T1 provides matching from 50 to 300 ohms and provides the 180 degrees of phase difference on the two outputs. Figure 2-1 Alford Loop Matching Network CCA Figure 2-2 Approximate Current Distribution for Each Element of the Alford Loop Radiator 2-2 Rev. G July, 2018 This document contains proprietary information and such information may not be disclosed to others for any purposes without written permission from Selex ES Inc.  MODEL 1150 DVOR ANTENNA Figure 2-3 Alford Loop Antenna Current Directions in One of the Four Half-Wave Elements 2.3 Detailed Theory of Operation The DVOR antenna system simulates a rotating arm with a transmitting antenna at each end, radiating the upper sideband signal from one end and the lower sideband signal from the other end. This is achieved electronically by using 48 antennas spaced equally around the perimeter of a circle 44 feet (13.4 meters) in diameter, with an antenna in the center of the circle radiating a reference carrier. Consider the effect of simulated antenna rotation on an airborne receiver. When the upper sideband source is moving toward the aircraft, the doppler effect causes the airborne receiver input frequency to become higher than fc+9960 Hz, and for the lower sideband source, which is moving away, the frequency becomes less than f c+9960 Hz, fc being the carrier frequency. The frequency difference changes sinusoidally due to the simulated rotation. The difference is maximized when the line joining the two radiating antennas is perpendicular to the radial to the aircraft. The difference is equal to zero when the two sideband sources align with the radial to the aircraft since, at that moment, the distance between each sideband source and the receiver does not vary. The moment of zero frequency deviation is different for different positions of the aircraft around the station. Therefore, the recovered 30 Hz FM signal will have a different phase for each of these different positions. For the receiver North of the DVOR station, the 30 Hz FM signal must be in phase with the 30 Hz AM signal; both signals passing through their positive zero crossings at the same time. To achieve this, the following has to be observed: At the moment that the 30 Hz amplitude modulation of the carrier is passing through its positive zero crossing, the simulated rotating antennas shall align with antenna number 1 (at North) and antenna number 25 (at South), with the North antenna radiating the lower sideband and the South antenna radiating the upper sideband. The lower sideband frequency will be decreasing; the upper increasing. The subcarrier frequency will be increasing from exactly 9960 Hz up and the 30 Hz FM signal will be passing through its positive zero crossing. Rev. G July, 2018 2-3 This document contains proprietary information and such information may not be disclosed to others for any purposes without written permission from Selex ES Inc. MODEL 1150 DVOR ANTENNA The relationship between the Doppler induced frequency modulated 30 Hz variable signal and the 30 Hz amplitude modulated carrier for receivers spaced around the DVOR station is best illustrated by Figure 2-4 through Figure 2-8. Generation of the azimuth-dependent FM by a DVOR station is depicted in Figure 2-4. It is assumed that the distance from the antenna array, shown as points A (sideband antenna) and M (reference antenna), to the aircraft receivers, shown as R1 and R2, is very much larger than the diameter of the array (distance D) and that, at the beginning of antenna array commutation, the antenna at the northern most point of the array is radiating an upper sideband signal. Since the lower sideband signal is similar to that of the upper sideband signal, only the upper sideband signal will be discussed. Antenna (signal) A traverses around antenna M in a counterclockwise direction. Four specific locations for antenna A are marked (positions 1, 2, 3, and 4). The rotation of antenna A with respect to antenna M causes receiver R1 to detect a variable signal that leads the reference signal by 270°. Receiver R2, however, is detecting a variable signal that leads the reference signal by 180°. Figure 2-5 is a vector representation of the FM and AM phase relationship at eight points about a DVOR station. Figure 2-4 Generation of Azimuth-Dependent FM by a DVOR Station 2-4 Rev. G July, 2018 This document contains proprietary information and such information may not be disclosed to others for any purposes without written permission from Selex ES Inc.  MODEL 1150 DVOR ANTENNA Figure 2-5 Phase Relationship of DVOR Course Forming Signals Figure 2-6 depicts aircraft receivers A, B, C, and D at the four cardinal points of a DVOR station. Shown, too, is the instantaneous direction of a rotating RF source at those points. Figure 2-7 is an illustration of the signals recovered by aircraft receivers A, B, C, and D. At the beginning of array commutation, aircraft receiver A perceives a radiating source moving to the west. Because at this instant (t = 0) the distance between receiver A and the radiating source is neither increasing nor decreasing, aircraft receiver A will recover an FM subcarrier which has no frequency deviation. The FM subcarrier has a frequency of 9960 Hz at this instant. A quarter of an antenna array commutation cycle later (t = 1/120 sec), the radiating point source is at the western most point of the array and is moving away from aircraft receiver A to the south at its greatest speed. From the Doppler effect, the FM subcarrier is frequency deviated downward by its maximum extent of 480 Hz. The FM subcarrier has a frequency of 9480 Hz at this instant (t = 1/120 sec). When the antenna array commutation has gone through one half of its cycle (t = 1/60), aircraft receiver A perceives a radiating point source at the southern most point of the array and moving directly east. At this time, the distance between the radiating source and the aircraft receiver is neither increasing nor decreasing; therefore, there is no Doppler induced frequency deviation of the FM subcarrier. The variable FM subcarrier has a frequency of 9960 Hz at this instant. Rev. G July, 2018 2-5 This document contains proprietary information and such information may not be disclosed to others for any purposes without written permission from Selex ES Inc. MODEL 1150 DVOR ANTENNA When the antenna array is commutated through three-fourths of its cycle (t = 3/120 sec), aircraft receiver A now perceives a radiating point source at the eastern most point of the array and moving toward it at its maximum speed. The Doppler effect frequency deviates the variable FM subcarrier upwards by its maximum extent of 480 Hz. The variable FM subcarrier has a frequency deviation of 10,440 Hz at this time. A further one quarter cycle of antenna array commutation brings the point source back to its northern most point and the process repeats. The variable FM subcarrier is detected in aircraft receiver A and is output as the detected 30 Hz FM variable signal. Aircraft receiver A also detects the 30 Hz amplitude modulated carrier and outputs a detected 30 Hz reference signal. The received reference AM signal and the detected 30 Hz AM reference are identical for receivers A, B, C, and D. An analysis similar to that for receiver A, but from the viewpoint of receivers B, C, and D yield the remaining variable FM subcarrier and detected 30 Hz FM variable waveforms shown in Figure 2-7. Aircraft receiver D has a bearing of 90° and from Figure 2-7 it can be seen that the detected 30 Hz FM variable signal leads the reference by one-quarter cycle, or 90°. Similarly for aircraft receiver C, the variable signal leads the reference by one-half cycle, or 180°, and the bearing of receiver C is 180°. Receiver B has a bearing of 270° and the variable signal leads the reference by three-fourths cycle or 270°. Aircraft Receiver A has a bearing of 0° and its two signals are in phase. The method of inducing the Doppler shift in the sideband is demonstrated by Figure 2-8. Again, for the purpose of this discussion, radiation from only one sideband element is assumed. For an observer located North of the DVOR station, the Doppler shift is most pronounced when the West and East antennas are radiating. No Doppler shift is present when the North and South antennas are radiating. With a counterclockwise rotation of the antenna, antenna #12 would emit RF energy and 1/1440 of a second later, antenna #13 would emit RF energy. Figure 2-8 shows the distance that each wave front has traveled in some unit length of time. The separation of the two wave fronts is equal to distance d1. A few moments later, antenna #36 is turned on causing it to emit RF energy. At 1/1440 of a second later, antenna #37 is conducting and radiating RF energy. After the same time period as before with antennas #12 and #13, the separation of the two wave fronts is measured and found to be distance d2. It is readily seen that d1 > d2. The distance of separation can be equated to time as the signals propagate through space; i.e., the time required for E max of each successive wave front to pass the observer. The reciprocal of time is frequency (1/t = f). Figure 2-6 Instantaneous Direction of an RF Source with Respect to Aircraft Receivers A, B, C and D 2-6 Rev. G July, 2018 This document contains proprietary information and such information may not be disclosed to others for any purposes without written permission from Selex ES Inc.  MODEL 1150 DVOR ANTENNA Figure 2-7 Received and Detected AM and FM Signals by Aircraft Receivers A, B, C, and D Due to the counterclockwise rotation of the sideband radiating elements, the western antenna would produce a Doppler shifted frequency that was less than the fundamental frequency (9960 Hz - 480 Hz). The eastern antenna would produce a frequency greater than the fundamental frequency (9960 Hz + 480 Hz). The northern and southern antennas would produce no shift. Figure 2-8 Doppler Shift (Wave Front Measurement) Rev. G July, 2018 2-7 This document contains proprietary information and such information may not be disclosed to others for any purposes without written permission from Selex ES Inc. MODEL 1150 DVOR ANTENNA Refer to Table 2-2 and Figure 2-9. It might be wrongly assumed that because the upper and lower sidebands are radiating from oppositely paired antenna (e.g., upper sideband on #12 and lower sideband on #36) that the two sidebands are producing opposite Doppler shifts. It is true that the fundamental sideband frequency is shifted downward (fUSB-480 Hz) when movement is west of the station and shifted upward (fLSB+480 Hz) when rotation is east of the station. However, after heterodyning, it can be seen that both the upper and lower sidebands are shifting in the same direction; i.e., from 9960 Hz to 9480 Hz, for the example given. (Heterodyning is the process of mixing two frequencies together in order to produce two other frequencies equal to the sum and difference of the first two.) Table 2-2 Doppler Shift Values from Heterodyning Upper Sideband (USB) fUSB fc East 108010440 - 108000000 = 10440 Hz No/So 108009960 - 108000000 = 9960 Hz West 108009480 - 108000000 = 9480 Hz West of the station the upper sideband frequency shifts from 108.009960 MHz to 108.009480 MHz or, after heterodyning, from 9960 Hz to 9480 Hz. Lower Sideband (LSB) fLSB fc East 107990520 - 108000000 = 9480 Hz No/So 107990040 - 108000000 = 9960 Hz West 107989560 - 108000000 = 10440 Hz East of the station the lower sideband frequency shifts from 107.990040 MHz to 107.990520 MHz or, after heterodyning, from 9960 Hz to 9480 Hz. Figure 2-9 Doppler Shift (Heterodyning) 2-8 Rev. G July, 2018 This document contains proprietary information and such information may not be disclosed to others for any purposes without written permission from Selex ES Inc.  MODEL 1150 DVOR ANTENNA 3.OPERATION 3.1 Introduction After initial installation and adjustment of the DVOR antenna, no operating procedures are required. Refer to DVOR system manual (571150-0002 or 571150A-0002) for system operating procedures. Rev. G July, 2018 3-1 This document contains proprietary information and such information may not be disclosed to others for any purposes without written permission from Selex ES Inc. MODEL 1150 DVOR ANTENNA THIS SHEET INTENTIONALLY BLANK 3-2 Rev. G July, 2018 This document contains proprietary information and such information may not be disclosed to others for any purposes without written permission from Selex ES Inc.  MODEL 1150 DVOR ANTENNA 4. STANDARDS AND TOLERANCES 4.1 Introduction Not applicable to this manual. Rev. G July, 2018 4-1 This document contains proprietary information and such information may not be disclosed to others for any purposes without written permission from Selex ES Inc. MODEL 1150 DVOR ANTENNA THIS SHEET INTENTIONALLY BLANK 4-2 Rev. G July, 2018 This document contains proprietary information and such information may not be disclosed to others for any purposes without written permission from Selex ES Inc.  MODEL 1150 DVOR ANTENNA 5. PERIODIC MAINTENANCE 5.1 Introduction This section contains performance checks and other preventive maintenance that must be performed periodically. Refer to Table 5-1 for a list of activities to be performed on a recurring basis. Table 5-1 Onsite Maintenance Step Description Period Reference Paragraph 1 Site Inspection Annual 6.3.1 2 Inspection of Antenna System Annual 6.3.2 3 Inspection of Field Monitor Annual 6.3.3 5.2 Performance Checks There are no assemblies that require performance checks. 5.3 Other Onsite Maintenance Table 5-2 contains a list of other onsite maintenance procedures that are necessary to ensure the DVOR antenna system is functioning properly. Table 5-2 Other Onsite Maintenance Reference Paragraph or Table Step Visual Inspections Standards and Maintenance Tolerances Procedures Site Inspection 1 Verify site inspection has been performed N/A 6.3.1 Antenna System Inspection 2 Verify antenna inspection has been performed N/A 6.3.2 Field Monitor Inspection 3 Verify field monitor inspection has been performed N/A 6.3.3 5.4 Offsite Maintenance There are no assemblies that require depot (offsite) periodic overhaul or calibration. Rev. G July, 2018 5-1 This document contains proprietary information and such information may not be disclosed to others for any purposes without written permission from Selex ES Inc. MODEL 1150 DVOR ANTENNA THIS SHEET INTENTIONALLY BLANK 5-2 Rev. G July, 2018 This document contains proprietary information and such information may not be disclosed to others for any purposes without written permission from Selex ES Inc.  MODEL 1150 DVOR ANTENNA 6. MAINTENANCE PROCEDURES 6.1 Introduction This section contains replacement and tune-up procedures for sideband and carrier antennas and RF cables. 6.2 Performance Check Procedures There are no assemblies that require performance checks. 6.3 Other Maintenance Procedures 6.3.1 Site Inspection Site inspections may be performed with the transmitter on, although walking on the counterpoise to remove obstructions may cause an alarm condition. Inspections to the antenna system (6.3.2) should be done with the DVOR transmitter off. Consult proper airport authority before taking the DVOR station off the air. a. Check that the site is clear of any new obstructions or materials which could affect the normal operation of the DVOR system. b. Check the shelter, inside and out, for any sign of water filtration, damage, or other deterioration. c. Check the condition of the air conditioner, shelter lighting, obstruction lights, baseboard heaters, electrical outlets, etc. d. Check for and remove any accumulation of snow, ice or debris on the counterpoise surface. 6.3.2 Inspection of the Antenna System a. Assure that both DVOR transmitters are turned off. b. With radomes removed, inspect the mating areas of the radomes where they connect with the antenna pedestal. Check for any signs of water leakage or deterioration. Repair or replace as necessary. c. Inspect the antenna elements for any signs of water damage or corrosion. Repair or replace as necessary. d. Check cables for vermin damage, loose or broken tie wraps, etc. Replace as necessary. e. Inspect the remaining parts of the antenna for signs of vermin infestation, corrosion, water damage, etc. Repair as necessary. f. Inspect the counterpoise for any signs of deterioration, paying special attention to welded joints, bolted connections, mesh, etc. Check for proper electrical connection between the counterpoise segments and grounding connections. Repair as necessary. g. Replace access covers and antenna radomes. h. Remove any articles carried onto the counterpoise. 6.3.3 Inspection of Field Monitor Antenna a. Inspect the condition of the field monitor antenna. Make sure it is solidly mounted and that all nuts and bolts are tightened. b. Inspect the condition of the field monitor antenna coaxial cables and tie wraps, for signs of cracks or breakage. Replace if necessary. c. Check for and remove any accumulation of snow, ice, or debris on the field monitor antenna. 6.4 Special Maintenance Procedures There are no assemblies that require special maintenance procedures. Rev. G July, 2018 6-1 This document contains proprietary information and such information may not be disclosed to others for any purposes without written permission from Selex ES Inc. MODEL 1150 DVOR ANTENNA THIS SHEET INTENTIONALLY BLANK 6-2 Rev. G July, 2018 This document contains proprietary information and such information may not be disclosed to others for any purposes without written permission from Selex ES Inc.  MODEL 1150 DVOR ANTENNA 7. CORRECTIVE MAINTENANCE 7.1 Introduction Not applicable to this manual. Rev. G July, 2018 7-1 This document contains proprietary information and such information may not be disclosed to others for any purposes without written permission from Selex ES Inc. MODEL 1150 DVOR ANTENNA THIS SHEET INTENTIONALLY BLANK 7-2 Rev. G July, 2018 This document contains proprietary information and such information may not be disclosed to others for any purposes without written permission from Selex ES Inc.  MODEL 1150 DVOR ANTENNA 8. PARTS LIST 8.1 Introduction This section contains the parts lists used in DVOR Antenna system. Table 8-1 and Table 8-2 lists the parts supplied in the Doppler Antenna Kit, refer to Figure 11-2; Table 8-3 contains a list of the parts supplied in the Stand Alone DVOR Carrier Antenna Kit; Table 8-4 contains a list of the parts supplied in the Carrier Antenna with Walk-in Radome Kit; Table 8-5 contains a list of the parts supplied in the Civil Installation Kit, refer to Figure 9-7. Table 8-6 contains a list of parts supplied in the Doppler Field Monitor Kit (470178-0002), refer to Figure 9-8. Table 8-1 Doppler Antenna Kit (48 Antenna) (470165-0003) Item No. Qty Part Number Description 1 48 030510-0002 Doppler Sideband Antenna Assy. 2 48 950394-0001 Sideband Antenna Radome Assy. 3 48 070350-9999 Positioning Piece (Specify Freq.) 4 48 950392-0003 Sideband Antenna Pedestal 6 400 136035-0000 Screw, Self-Drilling, 1/4-20 x 1-1/2” 7 48 702043-0002 Plate, Level Antenna 8 200 302044-0000 2" Retaining Strap 9 150 327079-0000 3/8-16 x 1-3/4" Machine Bolt 10 600 137000-0815.438 x 1 x.083 Flat Washer 11 300 136504-0141 3/8" Lock Washer 12 600 137500-2384 3/8-16 Hex Nut 14 150 347135-0430 Bolt, Sq Neck 3/8-16 x 3” 16 49 070503-0001 Cable Assembly-SP 18 48 185230-0000 Adapter, Conn, Type N 19 48 070351-0001 Tuning Stub 20 48 070352-0001 Sideband Antenna Balun 21 2 900065-0000 Sealing Compound 23 500 302114-0002 Tiedown Strap 24 100 302102-0595 Tiedown Strap 25 48 185209-0000 UG-27C, Plug Jack Connector Adapter 26 50 347083-0003 Adapter, Elec Conduit, 1” PVC 27 50 347107-0004 Locknut, Rigid Conduit, 1” Steel 33 400 327637-0000 Screw, Captive Southco Slotted Head 35 200 136504-0139 1/4" Lock Washer 37 200 136000-0079 1/4-20 x 1/2" Machine Screw 42 200 327081-0000 Washer, Flat, Fender, 1/4” ID x 1 “ OD 43 12 137527-0000 Clip, Rcpt, SST, Southco, 12-11027-12 Rev. G July, 2018 8-1 This document contains proprietary information and such information may not be disclosed to others for any purposes without written permission from Selex ES Inc. MODEL 1150 DVOR ANTENNA Table 8-2 Doppler Antenna Kit (48 Antenna) (470165-0004) Item No. Qty Part Number Description 1 48 030855-0001 Doppler Sideband Antenna Assy. 2 48 950394-0001 Sideband Antenna Radome Assy. 4 48 950392-0003 Sideband Antenna Pedestal 6 400 136035-0000 Screw, Self-Drilling, 1/4-20 x 1-1/2” 7 48 702043-0002 Plate, Level Antenna 8 200 302044-0000 2" Retaining Strap 9 200 327079-0000 3/8-16 x 1-3/4" Machine Bolt 10 500 137000-0815.438 x 1 x.083 Flat Washer 11 350 136504-0141 3/8" Lock Washer 12 450 137500-2384 3/8-16 Hex Nut 14 150 347135-0430 Bolt, Sq Neck 3/8-16 x 3” 16 49 070503-0001 Cable Assembly-SP 21 2 900065-0000 Sealing Compound 23 500 302114-0002 Tiedown Strap 24 100 302102-0595 Tiedown Strap 26 50 347083-0003 Adapter, Elec Conduit, 1” PVC 27 50 347107-0004 Locknut, Rigid Conduit, 1” Steel 33 400 327637-0000 Screw, Captive Southco Slotted Head 35 200 136504-0139 1/4" Lock Washer 37 200 136000-0079 1/4-20 x 1/2" Machine Screw 42 200 327081-0000 Washer, Flat, Fender, 1/4” ID x 1 “ OD 43 12 137527-0000 Clip, Rcpt, SST, Southco, 12-11027-12 8-2 Rev. G July, 2018 This document contains proprietary information and such information may not be disclosed to others for any purposes without written permission from Selex ES Inc.  MODEL 1150 DVOR ANTENNA Table 8-3 Stand Alone DVOR Carrier Antenna Kit (470209-0001) Item No. Qty Part Number Description 1 1 030570-0001 Loop Antenna Assy. 2 1 950394-0001 Sideband Antenna Radome Assy. 3 1 950392-0003 Antenna Pedestal 4 1 070352-0001 Sideband Antenna Balun 5 1 070351-0001 Tuning Stub 6 1 185230-0000 Type-N Adapter 7 1 185209-0000 UG-27C, Plug Jack Connector Adapter 8 1 070350-9999 Positioning Piece (Specify Freq.) 9 8 137000-0815 Flat Washer, #7/16,1.0 OD,.083 THK 10 8 327079-0000 3/8-16 x 1-3/4" Machine Bolt 11 8 136504-0141 3/8" Lock Washer 12 8 137500-2384 3/8-16 Hex Nut 13 4 137002-0014.395" x.750" Slotted Washer 14 1 702043-0001 Plate, Level, Antenna 15 10 136035-0000 Screw, Self-Drilling, 1/4-20 x 1-1/2” 16 6 136008-0063 10-32 x 1/2" Machine Screw 17 6 136504-0138 No. 10 Lock Washer 18 6 137000-0809.250 x.562 x.065 Flat Washer 19 10 327637-0000 Screw, Captive 20 4 347135-0450 Bolt, Sq Neck, 3/8-16 x 5” 21 1 347083-0003 Adapter, Elec Cnd, 1” PVC 22 1 347107-0004 Locknut, Rigid Cnd, 1” 23 4 137527-0000 Clip, Rcpt,.11/.16 Thick Panel Rev. G July, 2018 8-3 This document contains proprietary information and such information may not be disclosed to others for any purposes without written permission from Selex ES Inc. MODEL 1150 DVOR ANTENNA Table 8-4 Carrier Antenna Kit with Walk-in Radome (470208-0001) Item No. Qty Part Number Description 1 1 030518-0002 Doppler Carrier Antenna Assy 2 5 136027-0314 1/4-20 x 2" Machine Bolt 3 5 137000-0810.281 x.625 x.065 Flat Washer 4 7 137501-0011 1/4-20 Hex Nut 5 2 136027-0378 3/8-16 x 5" Machine Bolt 6 4 136027-0318 1/4-20 x 3" SST. Machine Bolt 7 1 070352-0001 Sideband Antenna Balun 8 1 070351-0001 Tuning Stub 9 1 185230-0000 Type-N Adapter 10 1 185209-0000 UG-27C, Plug Jack Connector Adapter 11 8 137000-0814.406 x.812 x.065 Flat Washer 12 8 327079-0000 3/8-16 x 1-3/4" Machine Bolt 13 8 136504-0141 3/8" Lock Washer 14 8 321014-0000 3/8-16 Hex Nut 15 4 137002-0014.395" x.750" Slotted Washer 18 1 801774-0001 Doppler Antenna Pedestal Cable Duct 19 4 801738-0001 Carrier Antenna Mounting Spacer Rod 20 2 801737-0001 Carrier Antenna Spacer Block Clamp 21 2 701798-0001 Carrier Antenna Special Half Clamp 22 1 070457-9999 Cable Assembly (Specify Freq.) Table 8-5 Civil Installation Kit Rohn Antenna (470252-0001) Item No. Qty Part Number Description 1 1 950181-0000 3-1/2' Rohn SB25G Tower 2 1 900076-0000 3/4" x 10' Copper Clad Steel Ground Rod 3 10 ft 146028-0002 No. 2 AWG Copper Wire 4 1 900130-0250 Conduit, MN, Rigid, 1" x 5' PVC 5 50 ft 146028-0040 Wire No. 4/0 Copper 6 1 347063-0002 3/4" Elbow, Electrical Conduit Table 8-6 Doppler Field Monitor Kit (470178-0002) Item No. Qty Part Number Description 1 1 443060-0450 1/4", 50 ohm, RF Cable 2 2 950180-0000 Rohn 25G 10 Foot Tower 3 1 400049-0000 Terminal Lug 4 1 180316-0001 1.20" x 0.44" TNC Connector 5 30 302043-0000 Black Tiedown Strap 6 1 030443-0002 Field Monitor Antenna Assembly 7 1 180387-0000 Type-N Connector 8 1 950180-0003 Rohn 25AG2 10' with 2-1/4" O.D. Pipe 9 6 in 900142-0003 Tubing,NM,3:1 Shrink 10 1 312056-0000 Tape, Weather-Proofing 8-4 Rev. G July, 2018 This document contains proprietary information and such information may not be disclosed to others for any purposes without written permission from Selex ES Inc.  MODEL 1150 DVOR ANTENNA 9. INSTALLATION, INTEGRATIONS AND CHECKOUT 9.1 Introduction This section contains the information required to install the antenna equipment, inspect the installation, perform startup and preliminary testing procedures, and perform an installation verification test. 9.2 Unpacking and Repacking Packing cases are to be handled and opened with care to avoid damage to electronics components. Be certain all fasteners, supports, and tie-downs have been removed before attempting to remove the units. Inspect all items for shipping damage and check against the packing slip to insure complete shipment. Check the packing slip against Table 1-2. 9.3 Test Equipment Required Refer to Table 1-3 for a list of test equipment that is required for installation. Table 9-1 Equipment Required for Installation but not Supplied Quantity Description 1 Theodolite 1 Electric Drill 9.4 Installation 9.4.1 Sideband Antenna Installation The sideband antennas must be mounted on a radius of 22 feet from the center of the counterpoise and evenly spaced at 7.5° intervals. They must be uniform in height and aligned with the carrier antenna which is mounted at the center of the counterpoise. There are two methods used in locating the sideband antennas on the counterpoise mounting rail: the theodolite method and the tape measure and spirit level method. The theodolite method is preferred as precision and accuracy insure a better signal in space. Rev. G July, 2018 9-1 This document contains proprietary information and such information may not be disclosed to others for any purposes without written permission from Selex ES Inc. MODEL 1150 DVOR ANTENNA 9.4.2 Theodolite Method Refer to Figure 9-1. Figure 9-1 Antenna Spacing on Counterpoise Mounting Rail Using Theodolite 9-2 Rev. G July, 2018 This document contains proprietary information and such information may not be disclosed to others for any purposes without written permission from Selex ES Inc.  MODEL 1150 DVOR ANTENNA a. Set up Theodolite in the center of the counterpoise. b. Locate the Magnetic North (0°) point on the counterpoise surface with the theodolite and mark it on the counterpoise. Set theodolite scale to 0°. c. Rotate the theodolite 7.5° + 0°2' and mark this point on counterpoise at 22 feet (6705 mm) from the center. Rotate theodolite another 7.5° ± 0°2' and mark this point on the counterpoise. Continue this procedure all the way around the counterpoise until you arrive back to the 0° mark. d. Evenly space all 48 sideband antenna pedestals (Part No. 950392-0002) using the marks to locate position. Locate the antenna pedestals with their access panels facing towards the center of the array. e. Insure that the North position is located on antenna 1. f. Check antenna pedestal positions using theodolite. g. If position is correct, refer to the 470165 drawing and Figure 9-2 to mount the sideband antenna pedestals to the mounting plates. h. Drive the self-drilling screws through the plate mounting holes and into the counterpoise. Figure 9-2 Antenna Placement on the Counterpoise i. Rotate theodolite 7.5° ± 0°2' and check position of the next sideband antenna pedestal. If position is correct attach sideband antenna pedestal as detailed in steps i thru m. j. Continue the process until all the sideband antenna pedestals have been securely attached to the counterpoise. k. Using the theodolite, level sideband antenna pedestal vertically and horizontally l. Place lower part of the radome on the pedestal. m. Attach sideband antenna assembly (Part No. 030510-0002or 030855-0001) to sideband pedestal using appropriate hardware. n. The antennas must radiate in line with their respective radial; that is, every other antenna must be 180 degrees out from the other, refer to Figure 9-1. At the same time, insure that the slot of the Alford loop antenna is on a radial with the center of the array. o. For operation at 114 MHz and higher cut the wire jumper on the 030855-0001 antenna. Ensure wire jumper cannot make future contact with itself. p. Place antenna radome cover (Part No. 950394-0001) on sideband antennas to protect the radiating elements in case of inclement weather. Rev. G July, 2018 9-3 This document contains proprietary information and such information may not be disclosed to others for any purposes without written permission from Selex ES Inc. MODEL 1150 DVOR ANTENNA 9.4.3 Tape Measure and Spirit Level Method a. Using a compass identify magnetic North (0°) and mark it on counterpoise surface. Make sure you are standing far enough away from the counterpoise so the steel in its construction will not interfere with the compass. b. Refer to Figure 9-3. Evenly space all 48 sideband antenna pedestals (Part No. 950392-0002) on the counterpoise. c. The antenna pedestals should have their access panels facing towards the center of the array. d. Place the first sideband antenna pedestal, sideband antenna #1, exactly centered on the North line of the counterpoise as seen from the center of the array. e. Measure 34.53 inches (877 mm) from North line (0° point on counterpoise) and mark this point on counterpoise. Center sideband antenna pedestal, sideband antenna #2, on this point. f. Using the North line as a starting point and while adding 34.53 inches (877 mm) to each pervious measurement, measure and mark locations for sideband antennas #3 through #25 on the counterpoise. Thus, sideband antenna #3 would be 69.06 inches (1754 mm) from North line, sideband antenna #4 would be 103.59 inches (2631 mm) from North line, and sideband antenna #5 would be 138.12 inches (3508 mm) from North line, etc. g. Using the North line as a starting point and while adding 34.53 inches (877 mm) to each pervious measurement, measure and mark locations for sideband antennas #47 through #24 on the counterpoise. Thus, sideband antenna #47 would be 69.06 inches (1754 mm) from North line, sideband antenna #46 would be 103.59 inches (2631 mm) from North line, and sideband antenna #45 would be 138.12 inches (3508 mm) from North line, etc. h. Attach sideband antenna pedestal #1 to counterpoise, using appropriate hardware, as shown in Figure 9-2. i. Using a carpenter’s level, level the sideband antenna pedestals vertically and horizontally. j. Attach sideband antenna pedestal #2 to the counterpoise and shown in Figure 9-2. k. Continue mounting all the sideband antenna pedestals. l. Attach sideband antenna assembly (Part No. 030510-0002or 030855-0001) to sideband pedestal using appropriate hardware. m. The antennas must radiate in line with their respective radial; that is, every other antenna must be 180 degrees out from the other, refer to Figure 9-3. At the same time insure that the slot of the Alford loop antenna is on a radial with the center of the array. n. For operation at 114 MHz and higher cut the wire jumper on the 030855-0001 antenna. Ensure wire jumper cannot make future contact with itself. o. Place antenna radomes (Part No. 950394-0001) on sideband antennas to protect the radiating elements in case of inclement weather. 9-4 Rev. G July, 2018 This document contains proprietary information and such information may not be disclosed to others for any purposes without written permission from Selex ES Inc.  MODEL 1150 DVOR ANTENNA Figure 9-3 Antenna Spacing on Counterpoise Mounting Rail Using Sight and Measurement Rev. G July, 2018 9-5 This document contains proprietary information and such information may not be disclosed to others for any purposes without written permission from Selex ES Inc. MODEL 1150 DVOR ANTENNA 9.4.4 Carrier Antenna Installation Refer to Figure 11-3 as applicable. a. Place carrier antenna pedestal in the center of the counterpoise. b. Attach carrier antenna mast to counterpoise, using appropriate hardware c. Using a carpenter’s level or a theodolite and.395" x 3/4" slotted washers (Part No. 137002-0014) as shims, level the carrier antenna mast vertically and horizontally. 9.4.5 Cutting a Replacement Antenna Feed Cable to Proper Electrical Length NOTE The 48 Sideband antenna feed cables have been assembled and tested to be within 5 degrees of each prior to delivery. No cutting is necessary in the field. This procedure is provided in order to replace a cable that may have been damaged. a. Measure and cut a fifty seven foot length of RF antenna cable. b. Install type-N connector (Part No. 180387-0000) on one end of the RF feed cable as detailed in Figure 9-4. Label antenna cables at both ends to match the appropriate antenna 1 through 48, to indicate which sideband antenna the cable will go to. c. Set Network Analyzer center frequency to 1/2 the operating frequency of station. This is done to prevent cutting the cable 180 degrees out of phase with the known good cables. d. Set Span to 10 MHz. e. Set Measurement to S11 (reflection). f. Calibrate the Network Analyzer using the 1 port method with a short, 50 ohm load and open circuit. g. Connect a Network Analyzer RF output test port to the reference cable or another good cable. h. Record the phase of the reference cable. i. Connect a Network Analyzer RF output test port to the cable to be cut. j. Trim the cable to within 2° of the cable used in calibration. k. Install type N-connector on the other end of RF feed cables as detailed in Figure 9-4. l. Change the Network Analyzer to the operating frequency of the station. m. Connect a Network Analyzer RF output test port to the reference cable. n. Record the phase of the reference cable. o. Connect a Network Analyzer RF output test port to the new cable. p. Verify that the new cable is within 5° of the reference cable. 9-6 Rev. G July, 2018 This document contains proprietary information and such information may not be disclosed to others for any purposes without written permission from Selex ES Inc.  MODEL 1150 DVOR ANTENNA Figure 9-4 RF Connector Assembly Diagram Rev. G July, 2018 9-7 This document contains proprietary information and such information may not be disclosed to others for any purposes without written permission from Selex ES Inc. MODEL 1150 DVOR ANTENNA Figure 9-5 Diagram of Feed Cable, Tuning Stub, Tee Connector and Positioning Piece Connections (This figure applies to the 470165-0003 Antenna Kit only) 9.4.6 Tuning the Sideband Antennas (PN 030510-0002) a. Using an ohmmeter, check all 50 ohm dummy loads. Replace those that are not 50 ohms ±1 ohm. b. Turn off AC and DC circuit breakers to the DVOR. c. Set the Network Analyzer for center frequency the same as the station frequency. d. Set the span for 5 MHz. Set for S11 operation. e. Select display and choose two windows. Set one for Log Magnitude. Set the second for VSWR. f. Select a Marker for the station frequency. g. Calibrate Network Analyzer for one port using open, short and dummy load. h. Connect antenna 1’s RF feed cable to Port 1 of the network analyzer. Dummy load the adjacent antennas; antenna 48 would be dummy loaded as well as antenna 2. i. While monitoring the Network Analyzer for VSWR, check the VSWR of antenna 1. Adjust the tuning capacitor for a VSWR of approximately 2.0. If the capacitor will not bring the antenna’s VSWR within specifications it may be necessary to trim the antenna tuning stub. 9-8 Rev. G July, 2018 This document contains proprietary information and such information may not be disclosed to others for any purposes without written permission from Selex ES Inc.  MODEL 1150 DVOR ANTENNA j. If trimming the antenna tuning stub is necessary trim approximately 1/8” (2mm) to 1/4” (5mm) each time. After trimming tuning stub adjust tuning capacitor to determine if the antenna’s VSWR will drop to approximately 2.0. k. Connect Network Analyzer to feed cable for antenna number 2 and dummy load the feed cables for antenna numbers 1 and 3. l. Tune antenna number 2 as detailed in steps i and j. m. Repeat steps i thru j for remaining sideband antennas while remembering to dummy load adjacent antennas to prevent reflections. n. Connect antenna 1’s RF feed cable to Port 1 of the network analyzer. Dummy load the adjacent antennas; antenna 48 would be dummy loaded as well as antenna 2. o. While monitoring the Network Analyzer for VSWR, check the VSWR of antenna 1. Adjust the tuning capacitor for a VSWR of approximately 1.3. If the capacitor will not bring the antenna’s VSWR within specifications it may be necessary to trim the antenna tuning stub. p. If trimming the antenna tuning stub is necessary trim approximately 1/8” (2mm) to 1/4” (5mm) each time. After trimming tuning stub adjust tuning capacitor to determine if the antenna’s VSWR will drop to approximately 1.3. q. Repeat the tuning for antennas 2 through 48 as detailed in steps o and p. r. Connect antenna 1’s RF feed cable to Port 1 of the network analyzer. Dummy load the adjacent antennas; antenna 48 would be dummy loaded as well as antenna 2. s. While monitoring the Network Analyzer for VSWR, check the VSWR of antenna 1. Adjust the tuning capacitor for a VSWR of 1.1 or better. If the capacitor will not bring the antenna’s VSWR within specifications it may be necessary to trim the antenna tuning stub. t. If trimming the antenna tuning stub is necessary trim 1/8” (2mm) or less each time. After trimming tuning stub adjust tuning capacitor to determine if the antenna’s VSWR will drop to 1.1 or less. 9.4.7 Tuning the Sideband Antennas (PN 030814-0001with Tuning CCA) a. Using an ohmmeter, check all 50 ohm dummy loads. Replace those that are not 50 ohms ±1 ohm. b. Turn off AC and DC circuit breakers to the DVOR. c. Set the Network Analyzer for center frequency the same as the station frequency. d. Set the span for 5 Mhz. Set for S11 operation. e. Select display and choose two windows. Set one for Log Magnitude. Set the second for VSWR. f. Select a Marker for the station frequency. g. Calibrate Network Analyzer for one port using open, short and dummy load. h. Connect antenna 1’s RF feed cable to Port 1 of the network analyzer. Dummy load the adjacent antennas; antenna 48 as well as antenna 2. i. While monitoring the Network Analyzer for VSWR, check the VSWR of antenna 1. Refer to Figure 9-6. Adjust the tuning capacitor C3 then C5 for a VSWR of approximately 2.0. NOTE It may be difficult to determine the position of C3 and C5. Each antenna position is rotated making it difficult to discern C3 from C5. When making the adjustment C3 will have the dominant effect over the frequency band and C5 will improve the VSWR once C5 is set. Rev. G July, 2018 9-9 This document contains proprietary information and such information may not be disclosed to others for any purposes without written permission from Selex ES Inc. MODEL 1150 DVOR ANTENNA Figure 9-6 Alford Loop Matching Network CCA j. Connect Network Analyzer to feed cable for antenna number 2 and dummy load the feed cables for antenna numbers 1 and 3. k. Tune antenna number 2 by adjusting the tuning capacitor C3 then C5 for a VSWR of approximately 2.0. l. Repeat steps k for remaining sideband antennas while remembering to dummy load adjacent antennas to prevent reflections. m. Connect antenna 1’s RF feed cable to Port 1 of the network analyzer. Dummy load the adjacent antennas. n. While monitoring the Network Analyzer for VSWR, check the VSWR of antenna 1. Adjust the tuning capacitor C3 then C5 for a VSWR of approximately 1.3. o. Repeat the tuning for antennas 2 through 48 for a VSWR of approximately 1.3. p. Connect antenna 1’s RF feed cable to Port 1 of the network analyzer. Dummy load the adjacent antennas. q. While monitoring the Network Analyzer for VSWR, check the VSWR of antenna 1. Adjust the tuning capacitor C3 then C5 for a VSWR of 1.1 or better. r. Repeat the tuning for antennas 2 through 48 for a VSWR of 1.1 or better. 9.4.8 Tuning the Carrier Antenna a. Connect RF carrier antenna cable to the Network Analyzer. b. Adjust or air-dielectric capacitor (depending on antenna) for a VSWR reading of 1.1 or less. If the capacitor will not bring the antenna’s VSWR within specifications it may be necessary to trim the antenna tuning stub. NOTE Air dielectric capacitor spacing should be equal between both capacitors. c. If trimming the antenna tuning stub is necessary trim 1/8” (2mm) or less. After trimming tuning stub adjust tuning capacitor to determine if the antenna’s VSWR will drop to 1.1 or below. 9.4.9 Checking Phase Length of Sideband Antennas Using the Carrier Antenna NOTE This procedure is used to verify that all Sideband antennas are radiating with same amplitude and phase. This procedure is used to validate Sideband cables and antennas. An out of tolerance condition can be the result of the antenna or the feed cable. a. Turn off AC and DC circuit breakers to the DVOR. b. Pull the Carrier Amplifiers and Sideband Amplifiers forward so that no power is applied to the assemblies. c. Connect Port 1 of the Network Analyzer to the Carrier antenna. d. Disconnect the Sideband 1 from J25 port of the Odd Commutator. 9-10 Rev. G July, 2018 This document contains proprietary information and such information may not be disclosed to others for any purposes without written permission from Selex ES Inc.  MODEL 1150 DVOR ANTENNA e. Set the Network Analyzer for center frequency the same as the station frequency. f. Set the span for 5 MHz. Set for S21 operation. g. Select display and choose two windows. Set one for Log Magnitude. Set the second for Phase. h. Select a Marker for the station frequency. i. Turn on the DVOR. j. Log onto the PMDT. Select Transmitters>> Commands>> Hold Commutator and select antenna 1. k. Perform a calibration of the Network Analyzer (Through type). This will make Sideband antenna 1 to the Carrier antenna as the reference reading. l. Select Transmitters>> Commands>> Hold Commutator and select antenna 3. m. Record the phase and amplitude for antenna 3. n. Repeat for odd antennas 5 through 47. o. Connect Port 1 of the Network Analyzer to the J25 (Sideband 2) input to the Even Commutator. (Do not calibrate). p. Select Transmitters>> Commands>> Hold Commutator and select antenna 2. q. Record the phase and amplitude for antenna 2. r. Repeat for odd antennas 4 through 48. s. All sideband antennas must be within 10° and 0.5 dB of each other. Investigate measurements that are outside this range. t. Disconnect the Network Analyzer and restore the DVOR to normal. 9.4.10 Field Monitor Antenna Foundation Installation Refer to Section 8 parts list, for a complete list of materials included in the Civil Installation Kit Rohn Antenna (Part No. 470252-0001). Figure 9-7 shows a typical DVOR Field Monitor Antenna foundation installation. DVOR Field Monitor Antenna foundation installation may vary per local building codes. Figure 9-7 Typical DVOR Field Monitor Antenna Foundation Installation Rev. G July, 2018 9-11 This document contains proprietary information and such information may not be disclosed to others for any purposes without written permission from Selex ES Inc. MODEL 1150 DVOR ANTENNA 9.4.11 Field Monitor Antenna (470178-0002) Installation Refer to Section 8 parts list for a complete list of materials included in the Doppler Field Monitor Antenna Kit (part no. 470178-0002). Refer to Figure 9-8. a. Set a 10 foot tower section (2) on foundation tower section, buried in concrete. Insure that bottom of tower is down. Secure the two sections together with six machine screws (1/4-20 x 1-1/2"), flat washers (1 x 1/4"), and hex nuts (1/4-20). Insure that terminal lug (grounding strap) (3) is attached to the tower. Attach the RF cable using tie wraps (part no. 443060-0450) to the tower. b. Set the last 10 foot tower section (2) on first tower section (2). Insure that bottom of tower is down. Secure the two sections together with six machine screws (1/4-20 x 1-1/2"), flat washers (1 x 1/4"), and hex nuts (1/4-20). c. Set the top tower section (8) on second tower section (2). Insure that bottom of tower is down. Secure the two sections together with six machine screws (1/4-20 x 1-1/2"), flat washers (1 x 1/4"), and hex nuts (1/4- 20). d. Install the Dipole antenna, clamps, U-bolts, and attaching hardware to the tower top pipe section. e. Install connectors on the RF cable (1) using shrink tubing (9) as necessary over cable/connector junctions. f. Apply weatherproofing kit (Item 10, Table 8-6) to seal the connection between antenna and signal cable per manufacturer’s instructions. Figure 9-8 DVOR Field Monitor Antenna and Tower (Part No. 470178-0002) Parts Location Diagram 9-12 Rev. G July, 2018 This document contains proprietary information and such information may not be disclosed to others for any purposes without written permission from Selex ES Inc.  MODEL 1150 DVOR ANTENNA 10. SOFTWARE 10.1 Introduction Not applicable to this manual. Rev. G July, 2018 10-1 This document contains proprietary information and such information may not be disclosed to others for any purposes without written permission from Selex ES Inc. MODEL 1150 DVOR ANTENN