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AUSTRALIAN ARMY CADETS RADIO OPERATORS COURSE
CADET ADVANCED RADIO OPERATORS COURSE This presentation corresponds to Chapter 11 of the AAC CADET INSTRUCTOR RADIO COMMUNICATIONS HANDBOOK This course has been designed, written and developed by LTCOL(AAC) G.R. Newman-Martin, CSM, RFD ©LTCOL(AAC) G.R. NEWMAN-MARTIN, 2011
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©LTCOL G.R. Newman-Martin 2011
Topic 11 ANTENNAS This presentation refers to Chapter 11 of the Instructor Notes. The theory part of this presentation should take one 40-minute instructional period to teach. A number of additional periods may be required to practice assembly and disassembly of the Antenna Equipment RC-292 and the Antenna Lightweight. ©LTCOL G.R. Newman-Martin 2011
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RADIO WAVES
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Radio Wave crest g fcrest RADIO WAVE – DIAGRAMMATIC REPRESENTATION
©LTCOL G.R. Newman-Martin 2011
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Radio Wave crest g fcrest h i amplitude
RADIO WAVE – DIAGRAMMATIC REPRESENTATION ©LTCOL G.R. Newman-Martin 2011
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Radio Wave Œf wavelength gŒ crest g fcrest h i amplitude
RADIO WAVE – DIAGRAMMATIC REPRESENTATION ©LTCOL G.R. Newman-Martin 2011
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©LTCOL G.R. Newman-Martin 2011
Radio Frequency ©LTCOL G.R. Newman-Martin 2011 14
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©LTCOL G.R. Newman-Martin 2011
Radio Frequency IF TIME FOR EACH CREST TO TRAVEL BY ONE WAVELENGTH IS ONE SECOND…. ©LTCOL G.R. Newman-Martin 2011
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©LTCOL G.R. Newman-Martin 2011
Radio Frequency IF TIME FOR EACH CREST TO TRAVEL BY ONE WAVELENGTH IS ONE SECOND…. THEN THE WAVE HAS A FREQUENCY OF 1 HERTZ (Hz) ©LTCOL G.R. Newman-Martin 2011
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©LTCOL G.R. Newman-Martin 2011
Radio Frequency IF TIME FOR EACH CREST TO TRAVEL BY ONE WAVELENGTH IS ONE SECOND… THEN THE WAVE HAS A FREQUENCY OF HERTZ (Hz) A FREQUENCY OF 1000 Hz IS CALLED A KILOHERTZ (kHz) [i.e. ‘1000 crests per second’] ©LTCOL G.R. Newman-Martin 2011
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©LTCOL G.R. Newman-Martin 2011
Radio Frequency IF TIME FOR EACH CREST TO TRAVEL BY ONE WAVELENGTH IS ONE SECOND, THE WAVE HAS A FREQUENCY OF 1 HERTZ (Hz) A FREQUENCY OF 1000 Hz IS CALLED A KILOHERTZ (kHz) A FREQUENCY OF 1 MILLION Hz IS CALLED A MEGAHERTZ (MHz) [‘1 million crests per second’] ©LTCOL G.R. Newman-Martin 2011
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©LTCOL G.R. Newman-Martin 2011
Radio Frequency bands RADIO FREQUENCY BANDS Designation Abbreviation Frequency band ©LTCOL G.R. Newman-Martin 2011
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©LTCOL G.R. Newman-Martin 2011
Radio Frequency bands RADIO FREQUENCY BANDS Designation High frequency Abbreviation HF Frequency band 3-30 MHz ©LTCOL G.R. Newman-Martin 2011
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©LTCOL G.R. Newman-Martin 2011
Radio Frequency bands RADIO FREQUENCY BANDS Designation High frequency Very high frequency Abbreviation HF VHF Frequency band 3-30 MHz MHz ©LTCOL G.R. Newman-Martin 2011
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©LTCOL G.R. Newman-Martin 2011
Radio Frequency bands RADIO FREQUENCY BANDS Designation High frequency Very high frequency Ultra High Frequency Abbreviation HF VHF UHF Frequency band 3-30 MHz MHz MHz ©LTCOL G.R. Newman-Martin 2011
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©LTCOL G.R. Newman-Martin 2011
Radio Frequency bands RADIO FREQUENCY BANDS Designation High frequency Very high frequency Ultra High Frequency Abbreviation HF VHF UHF Frequency band 3-30 MHz MHz MHz EXAMPLE – THE AN/PRC-77 RADIO SET IS A VHF RADIO WHICH OPERATES IN THE 30 – 80 MHz RANGE ©LTCOL G.R. Newman-Martin 2011
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©LTCOL G.R. Newman-Martin 2011
What is an antenna? ©LTCOL G.R. Newman-Martin 2011
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©LTCOL G.R. Newman-Martin 2011
What is an antenna? An antenna is a conductor used to radiate or collect radio waves ©LTCOL G.R. Newman-Martin 2011
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©LTCOL G.R. Newman-Martin 2011
What is an antenna? An antenna is a conductor used to radiate or collect radio waves When an antenna receives a radio signal, it turns electromagnetic energy into electrical voltage ©LTCOL G.R. Newman-Martin 2011
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©LTCOL G.R. Newman-Martin 2011
What is an antenna? An antenna is a conductor used to radiate or collect radio waves When an antenna receives a radio signal, it turns electromagnetic energy into electrical voltage During transmission it turns changing voltage into electromagnetic energy ©LTCOL G.R. Newman-Martin 2011
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©LTCOL G.R. Newman-Martin 2011
What is an antenna? An antenna is a conductor used to radiate or collect radio waves When an antenna receives a radio signal, it turns electromagnetic energy into electrical voltage During transmission it turns changing voltage into electromagnetic energy The most basic antenna is a piece of wire ©LTCOL G.R. Newman-Martin 2011
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What factors reduce power of radio waves?
Radio waves are reduced in power, or ‘attenuated’, by factors such as: ©LTCOL G.R. Newman-Martin 2011
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What factors reduce power of radio waves?
Radio waves are reduced in power, or ‘attenuated’, by factors such as: effects of the ionosphere ©LTCOL G.R. Newman-Martin 2011
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What factors reduce power of radio waves?
Radio waves are reduced in power, or ‘attenuated’, by factors such as: effects of the ionosphere frequency of the radio waves ©LTCOL G.R. Newman-Martin 2011
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What factors reduce power of radio waves?
Radio waves are reduced in power, or ‘attenuated’, by factors such as: effects of the ionosphere frequency of the radio waves obstacles such as trees, hill and buildings ©LTCOL G.R. Newman-Martin 2011
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What factors reduce power of radio waves?
Radio waves are reduced in power, or ‘attenuated’, by factors such as: effects of the ionosphere frequency of the radio waves obstacles such as trees, hill and buildings power lines ©LTCOL G.R. Newman-Martin 2011
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What factors reduce power of radio waves?
Radio waves are reduced in power, or ‘attenuated’, by factors such as: effects of the ionosphere frequency of the radio waves obstacles such as trees, hill and buildings power lines distance from the transmitter ©LTCOL G.R. Newman-Martin 2011
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What factors reduce power of radio waves?
No matter how strong the transmission power, the further the distance from the transmitter, the weaker the signal received will be. ©LTCOL G.R. Newman-Martin 2011
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What factors reduce power of radio waves?
No matter how strong the transmission power, the further the distance from the transmitter, the weaker the signal received will be. Eventually the signal becomes so weak that natural and atmospheric noise are greater than the original signal ©LTCOL G.R. Newman-Martin 2011
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Why are antennas needed?
An antenna is necessary to collect radio signals, which are then amplified in a radio set and converted into audible sounds ©LTCOL G.R. Newman-Martin 2011
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Calculation of antenna length
©LTCOL G.R. Newman-Martin 2011
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Calculation of antenna length
For greatest efficiency an antenna should be one wavelength long ©LTCOL G.R. Newman-Martin 2011
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Calculation of antenna length
For greatest efficiency an antenna should be one wavelength long Wavelength calculated from formula: ©LTCOL G.R. Newman-Martin 2011
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Calculation of antenna length
For greatest efficiency an antenna should be one wavelength long Wavelength calculated from formula: wavelength = 300,000, frequency (in hertz) ©LTCOL G.R. Newman-Martin 2011
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Calculation of antenna length
For greatest efficiency an antenna should be one wavelength long Wavelength calculated from formula: wavelength = 300,000, frequency (in hertz) = 300 frequency (in megahertz) ©LTCOL G.R. Newman-Martin 2011
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Calculation of antenna length
For greatest efficiency an antenna should be one wavelength long Wavelength calculated from formula: wavelength = 300,000, frequency (in hertz) = 300 frequency (in megahertz) = antenna length (in metres) ©LTCOL G.R. Newman-Martin 2011
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Calculation of wavelength
Example- Radio Set AN/PRC-77, operating in 30 – 80 MHz range ©LTCOL G.R. Newman-Martin 2011
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Calculation of wavelength
Example- Radio Set AN/PRC-77, operating in 30 – 80 MHz range Wavelength calculated from formula: at frequency of 30 MHz wavelength = 300 30 = 10 metres ©LTCOL G.R. Newman-Martin 2011
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Calculation of wavelength
Example- Radio Set AN/PRC-77, operating in 30 – 80 MHz range Wavelength calculated from formula: at frequency of 80 MHz wavelength = 300 80 = 3.75 metres ©LTCOL G.R. Newman-Martin 2011
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Reducing length of antennas
©LTCOL G.R. Newman-Martin 2011
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Reducing length of antennas
It is often impractical to use such a long antenna in the field ©LTCOL G.R. Newman-Martin 2011
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Reducing length of antennas
It is often impractical to use such a long antenna in the field Antennas can still be effective if their physical length is reduced but efficiency will be slightly reduced. ©LTCOL G.R. Newman-Martin 2011
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Reducing length of antennas
It is often impractical to use such a long antenna in the field Antennas can still be effective if their physical length is reduced but efficiency will be slightly reduced. The reduction in length must be in one of the following fractions of wavelength: 3/8 or 5/8 or 7/8 ©LTCOL G.R. Newman-Martin 2011
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Reducing length of antennas
It is often impractical to use such a long antenna in the field Antennas can still be effective if their physical length is reduced but efficiency will be slightly reduced. The reduction in length must be in one of the following fractions of wavelength: 3/8 or 5/8 or 7/8 ¼ or ¾ ©LTCOL G.R. Newman-Martin 2011
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Reducing length of antennas
It is often impractical to use such a long antenna in the field Antennas can still be effective if their physical length is reduced but efficiency will be slightly reduced. The reduction in length must be in one of the following fractions of wavelength: 3/8 or 5/8 or 7/8 ¼ or ¾ ©LTCOL G.R. Newman-Martin 2011
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‘End Effect’
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©LTCOL G.R. Newman-Martin 2011
‘End Effect’ Insulators etc used to support antenna cause additional ‘loading’ to antenna ©LTCOL G.R. Newman-Martin 2011
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©LTCOL G.R. Newman-Martin 2011
‘End Effect’ Insulators etc used to support antenna cause additional ‘loading to antenna This makes antenna behave as if it is longer electrically than it is physically ©LTCOL G.R. Newman-Martin 2011
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©LTCOL G.R. Newman-Martin 2011
‘End Effect’ Insulators etc used to support antenna cause additional ‘loading to antenna This makes antenna behave as if it is longer electrically than it is physically This is called ‘end effect’ ©LTCOL G.R. Newman-Martin 2011
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©LTCOL G.R. Newman-Martin 2011
‘End Effect’ Insulators etc used to support antenna cause additional ‘loading to antenna This makes antenna behave as if it is longer electrically than it is physically This is called ‘end effect’ End effect makes antenna resonate at lower frequency than set on radio ©LTCOL G.R. Newman-Martin 2011
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©LTCOL G.R. Newman-Martin 2011
‘End Effect’ Insulators etc used to support antenna cause additional ‘loading to antenna This makes antenna behave as if it is longer electrically than it is physically This is called ‘end effect’ End effect makes antenna resonate at lower frequency than set on radio This is overcome by reducing length of antenna by 5% ©LTCOL G.R. Newman-Martin 2011
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©LTCOL G.R. Newman-Martin 2011
‘End Effect’ Insulators etc used to support antenna cause additional ‘loading to antenna This makes antenna behave as if it is longer electrically than it is physically This is called ‘end effect’ End effect makes antenna resonate at lower frequency than set on radio This is overcome by reducing length of antenna by 5% Most common way to reduce antenna length is to use quarter wave antenna (1/4 of wavelength in length). ©LTCOL G.R. Newman-Martin 2011
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©LTCOL G.R. Newman-Martin 2011
‘End Effect’ Formula to calculate antenna length, quarter wave antenna, accounting for end effect, is: ©LTCOL G.R. Newman-Martin 2011
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©LTCOL G.R. Newman-Martin 2011
‘End Effect’ Formula to calculate antenna length, quarter wave antenna, accounting for end effect, is: Antenna length (metres) = 71.25_________ frequency (MHz) ©LTCOL G.R. Newman-Martin 2011
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©LTCOL G.R. Newman-Martin 2011
‘End Effect’ Formula to calculate antenna length, quarter wave antenna, accounting for end effect, is: Antenna length (metres) = 71.25_________ frequency (MHz) Example, AN/PRC-77 radio set operating on 30 MHz 30 = metres ©LTCOL G.R. Newman-Martin 2011
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©LTCOL G.R. Newman-Martin 2011
‘End Effect’ Formula to calculate antenna length, quarter wave antenna, accounting for end effect, is: Antenna length (metres) = 71.25_________ frequency (MHz) Example, AN/PRC-77 radio set operating on 30 MHz 30 = metres 80 = 0.89 metres ©LTCOL G.R. Newman-Martin 2011
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©LTCOL G.R. Newman-Martin 2011
Types of Antennas ©LTCOL G.R. Newman-Martin 2011
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©LTCOL G.R. Newman-Martin 2011
Types of Antennas There are basically 3 types of antennas 1. Omni-directional 2. Bi-directional 3. Uni-directional ©LTCOL G.R. Newman-Martin 2011
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Omni-directional antennas
Omni-directional antennas are capable of transmitting in all directions ©LTCOL G.R. Newman-Martin 2011
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Omni-directional antennas
Omni-directional antennas are capable of transmitting in all directions Vertical antennas are omni-directional antennas ©LTCOL G.R. Newman-Martin 2011
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Omni-directional antennas
Omni-directional antennas are capable of transmitting in all directions Vertical antennas are omni-directional antennas Vertical antennas are the most widely used in field environment because: ©LTCOL G.R. Newman-Martin 2011
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Omni-directional antennas
Omni-directional antennas are capable of transmitting in all directions Vertical antennas are omni-directional antennas Vertical antennas are the most widely used in field environment because: they are easy to erect in ‘whip’ configuration they can be used with mobile radios ©LTCOL G.R. Newman-Martin 2011
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©LTCOL G.R. Newman-Martin 2011
Types of vertical antennas ©LTCOL G.R. Newman-Martin 2011 24
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Types of vertical antennas
manpack whip antennas ©LTCOL G.R. Newman-Martin 2011
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Types of vertical antennas
manpack whip antennas vertical wire antennas ©LTCOL G.R. Newman-Martin 2011
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Types of vertical antennas
manpack whip antennas vertical wire antennas vehicle dipole antennas ©LTCOL G.R. Newman-Martin 2011
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Types of vertical antennas
manpack whip antennas vertical wire antennas vehicle dipole antennas elevated antennas ©LTCOL G.R. Newman-Martin 2011
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©LTCOL G.R. Newman-Martin 2011
Manpack whip antennas ©LTCOL G.R. Newman-Martin 2011
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©LTCOL G.R. Newman-Martin 2011
Manpack whip antennas types include: battle whip (or low profile) antennas rod antennas ©LTCOL G.R. Newman-Martin 2011
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©LTCOL G.R. Newman-Martin 2011
Manpack whip antennas types include: battle whip (or low profile) antennas rod antennas example – long (3 metre) foldable multi- section or ‘whip’ antenna - Radio Set AN/PRC-77 ©LTCOL G.R. Newman-Martin 2011
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©LTCOL G.R. Newman-Martin 2011
Manpack whip antennas types include: battle whip (or low profile) antennas rod antennas example – log (3 metre) foldable multi- section or ‘whip’ antenna - Radio Set AN/PRC-77 ‘broadband’ – suitable for range of frequencies ©LTCOL G.R. Newman-Martin 2011
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©LTCOL G.R. Newman-Martin 2011
Manpack whip antennas types include: battle whip (or low profile) antennas rod antennas example – log (3 metre) foldable multi- section or ‘whip’ antenna - Radio Set AN/PRC-77 ‘broadband’ – suitable for range of frequencies designed so that casing of radio set is ‘ground reflecting element’ of antenna ©LTCOL G.R. Newman-Martin 2011
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©LTCOL G.R. Newman-Martin 2011
Manpack whip antennas types include: battle whip (or low profile) antennas rod antennas example – log (3 metre) foldable multi- section or ‘whip’ antenna - Radio Set AN/PRC-77 normally ‘broadband’ – suitable for range of frequencies designed so that casing of radio set is ‘ground reflecting element’ of antenna used to aid camouflage and mobility ©LTCOL G.R. Newman-Martin 2011
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©LTCOL G.R. Newman-Martin 2011
Manpack whip antennas types include: battle whip (or low profile) antennas rod antennas example – log (3 metre) foldable multi- section or ‘whip’ antenna - Radio Set AN/PRC-77 normally ‘broadband’ – suitable for range of frequencies designed so that casing of radio set is the ‘ground reflecting element’ of the antenna used to aid camouflage and mobility if broken, a piece of wire – the same length as the original – can be used as a substitute ©LTCOL G.R. Newman-Martin 2011
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©LTCOL G.R. Newman-Martin 2011
V E R T I C A L W I R E A N T S ©LTCOL G.R. Newman-Martin 2011 19
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Vertical wire antennas
If whip cannot be repaired, a substitute vertical wire antenna can be made – ©LTCOL G.R. Newman-Martin 2011
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Vertical wire antennas
If whip cannot be repaired, a substitute vertical wire antenna can be made – one wavelength is ideal (but a quarter of one wavelength could also be used = ‘quarter wave antenna’) ©LTCOL G.R. Newman-Martin 2011
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Vertical wire antennas
If whip cannot be repaired, a substitute vertical wire antenna can be made – one wavelength is ideal (but a quarter of one wavelength could also be used = ‘quarter wave antenna’) ©LTCOL G.R. Newman-Martin 2011
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Vertical wire antennas
If whip cannot be repaired, a substitute vertical wire antenna can be made – one wavelength is ideal (but a quarter of one wavelength could also be used = ‘quarter wave antenna’) rope ties insulator to tree insulator antenna wire radio set earth ©LTCOL G.R. Newman-Martin 2011
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Vertical wire antennas
If whip cannot be repaired, a substitute vertical wire antenna can be made – one wavelength is ideal (but a quarter of one wavelength could also be used = ‘quarter wave antenna’) rope ties insulator to tree insulator antenna wire radio set earth rope wrapped around tree to hold substitute vertical antenna in place ©LTCOL G.R. Newman-Martin 2011
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©LTCOL G.R. Newman-Martin 2011
Inverted ‘L’ antenna Supports may not be high enough for a full wavelength or quarter wavelength antenna to be erected vertically ©LTCOL G.R. Newman-Martin 2011
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©LTCOL G.R. Newman-Martin 2011
Inverted ‘L’ antenna Supports may not be high enough for a full wavelength or quarter wavelength antenna to be erected vertically In this case, the top may be bent over horizontally (‘b’) xx ©LTCOL G.R. Newman-Martin 2011
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©LTCOL G.R. Newman-Martin 2011
Inverted ‘L’ antenna Supports may not be high enough for a full wavelength or quarter wavelength antenna to be erected vertically In this case, the top may be bent over horizontally (‘b’) This resembles an inverted ‘L’ xx ©LTCOL G.R. Newman-Martin 2011
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©LTCOL G.R. Newman-Martin 2011
Inverted ‘L’ antenna Supports may not be high enough for a full wavelength or quarter wavelength antenna to be erected vertically In this case, the top may be bent over horizontally (‘b’) This resembles an inverted ‘L’ ‘a’ radiates ground wave. ‘b’ radiates sky wave. xx ©LTCOL G.R. Newman-Martin 2011
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©LTCOL G.R. Newman-Martin 2011
Inverted ‘L’ antenna Supports may not be high enough for a full wavelength or quarter wavelength antenna to be erected vertically In this case, the top may be bent over horizontally (‘b’) This resembles an ‘inverted ‘L’ ‘a’ radiates ground wave. ‘b’ radiates sky wave. ‘a’ should be as long as possible xx ©LTCOL G.R. Newman-Martin 2011
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©LTCOL G.R. Newman-Martin 2011
Inverted ‘L’ antenna Supports may not be high enough for a full wavelength or quarter wavelength antenna to be erected vertically In this case, the top may be bent over horizontally (‘b’) This resembles an ‘inverted ‘L’ ‘a’ radiates ground wave. ‘b’ radiates sky wave. ‘a’ should be as long as possible ‘a’+‘b’ add up to a quarter of a wave-length = l/4 xx ©LTCOL G.R. Newman-Martin 2011
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©LTCOL G.R. Newman-Martin 2011
Inverted ‘L’ antenna Supports may not be high enough for a full wavelength or quarter wavelength antenna to be erected vertically In this case, the top may be bent over horizontally (‘b’) This resembles an ‘inverted ‘L’ ‘a’ radiates ground wave. ‘b’ radiates sky wave. ‘a’ should be as long as possible ‘a’+‘b’ add up to a quarter of a wave-length = l/4 Remaining supports are insulated from antenna xx ©LTCOL G.R. Newman-Martin 2011
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©LTCOL G.R. Newman-Martin 2011
Inverted ‘L’ antenna Supports may not be high enough for a full wavelength or quarter wavelength antenna to be erected vertically In this case, the top may be bent over horizontally (‘b’) This resembles an ‘inverted ‘L’ ‘a’ radiates ground wave. ‘b’ radiates sky wave. ‘a’ should be as long as possible ‘a’+‘b’ add up to a quarter of a wave-length = l/4 Remaining supports are insulated from antenna symbol ¡ in diagram represents insulator xx ©LTCOL G.R. Newman-Martin 2011
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©LTCOL G.R. Newman-Martin 2011
Dipole antenna Made from two lengths of straight conductor (metal wire) ©LTCOL G.R. Newman-Martin 2011
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©LTCOL G.R. Newman-Martin 2011
Dipole antenna Made from two lengths of straight conductor (metal wire) Transmitted waves will be either horizontally or vertically ‘polarised’ depending on whether antenna is horizontal or vertical. ©LTCOL G.R. Newman-Martin 2011
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©LTCOL G.R. Newman-Martin 2011
Dipole antenna Made from two lengths of straight conductor (metal wire) Transmitted waves will be either horizontally or vertically ‘polarised’ depending on whether antenna is horizontal or vertical. Half-wave dipole antenna ©LTCOL G.R. Newman-Martin 2011
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©LTCOL G.R. Newman-Martin 2011
Dipole antenna Made from two lengths of straight conductor (metal wire) Transmitted waves will be either horizontally or vertically ‘polarised’ depending on whether antenna is horizontal or vertical. Receiving and transmitting antennas need to be either both horizontal or both vertical. Half-wave dipole antenna ©LTCOL G.R. Newman-Martin 2011
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Folded dipole antennas
A single rod of one half wavelength can be folded over ©LTCOL G.R. Newman-Martin 2011
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Folded dipole antennas
A single rod of one half wavelength can be folded over Its folded length is still half a wavelength ©LTCOL G.R. Newman-Martin 2011
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Folded dipole antennas
A single rod of one half wavelength can be folded over. Its folded length is still half a wavelength This minimises signal loss ©LTCOL G.R. Newman-Martin 2011
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Folded dipole antennas
A single rod of one half wavelength can be folded over. Its folded length is still half a wavelength This minimises signal loss Folded half-wave dipole antenna ©LTCOL G.R. Newman-Martin 2011
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©LTCOL G.R. Newman-Martin 2011
Elevated antennas ©LTCOL G.R. Newman-Martin 2011 19
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©LTCOL G.R. Newman-Martin 2011
Elevated antennas Communications in the VHF band will be more effective if the height of the antenna can be increased ©LTCOL G.R. Newman-Martin 2011
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©LTCOL G.R. Newman-Martin 2011
Elevated antennas Communications in the VHF band will be more effective if the height of the antenna can be increased This helps especially if antenna is lifted above height of surrounding obstacles ©LTCOL G.R. Newman-Martin 2011
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©LTCOL G.R. Newman-Martin 2011
Elevated antennas Communications in the VHF band will be more effective if the height of the antenna can be increased This helps especially if antenna is lifted above height of surrounding obstacles This increases possibility of ‘line-of-sight’ between transmitting an receiving antennas ©LTCOL G.R. Newman-Martin 2011
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©LTCOL G.R. Newman-Martin 2011
Elevated antennas Communications in the VHF band will be more effective if the height of the antenna can be increased This helps especially if antenna is lifted above height of surrounding obstacles This increases possibility of ‘line-of-sight’ between transmitting an receiving antennas Elevation of antennas can be increased by: ©LTCOL G.R. Newman-Martin 2011
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©LTCOL G.R. Newman-Martin 2011
Elevated antennas Communications in the VHF band will be more effective if the height of the antenna can be increased This helps especially if antenna is lifted above height of surrounding obstacles This increases possibility of ‘line-of-sight’ between transmitting an receiving antennas Elevation of antennas can be increased by: Placing radio on higher ground ©LTCOL G.R. Newman-Martin 2011
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©LTCOL G.R. Newman-Martin 2011
Elevated antennas Communications in the VHF band will be more effective if the height of the antenna can be increased This helps especially if antenna is lifted above height of surrounding obstacles This increases possibility of ‘line-of-sight’ between transmitting an receiving antennas Elevation of antennas can be increased by: Placing radio on higher ground Hoisting antenna up tall objects ©LTCOL G.R. Newman-Martin 2011
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©LTCOL G.R. Newman-Martin 2011
Elevated antennas Communications in the VHF band will be more effective if the height of the antenna can be increased This helps especially if antenna is lifted above height of surrounding obstacles This increases possibility of ‘line-of-sight’ between transmitting an receiving antennas Elevation of antennas can be increased by: Placing radio on higher ground Hoisting antenna up tall objects Placing antenna up a tall mast (e.g. RC-292 Radio Antenna Equipment mast) ©LTCOL G.R. Newman-Martin 2011
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©LTCOL G.R. Newman-Martin 2011
RC-292 ANTENNA EQUIPMENT ©LTCOL G.R. Newman-Martin 2011
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©LTCOL G.R. Newman-Martin 2011
RC-292 Antenna equipment RC-292 ANTENNA EQUIPMENT ©LTCOL G.R. Newman-Martin 2011
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©LTCOL G.R. Newman-Martin 2011
RC-292 Antenna equipment Demountable antenna system designed to increase range of Radio Set AN/PRC-77 ©LTCOL G.R. Newman-Martin 2011
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©LTCOL G.R. Newman-Martin 2011
RC-292 Antenna equipment Demountable antenna system designed to increase range of Radio Set AN/PRC-77 Elevated mast-mounted ground plane antenna ©LTCOL G.R. Newman-Martin 2011
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©LTCOL G.R. Newman-Martin 2011
RC-292 Antenna equipment Demountable antenna system designed to increase range of Radio Set AN/PRC-77 Elevated mast-mounted ground plane antenna. Omni-directional ©LTCOL G.R. Newman-Martin 2011
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©LTCOL G.R. Newman-Martin 2011
RC-292 Antenna equipment Demountable antenna system designed to increase range of Radio Set AN/PRC-77 Elevated mast-mounted ground plane antenna. Omni-directional Antenna can be elevated on 30 ft ( 9 m) (maximum) vertical mast (interlocking tubing sections) held in place by guy ropes & ground stakes ©LTCOL G.R. Newman-Martin 2011
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©LTCOL G.R. Newman-Martin 2011
RC-292 Antenna equipment Demountable antenna system designed to increase range of Radio Set AN/PRC-77 Elevated mast-mounted ground plane antenna. Omni-directional Antenna can be elevated on 30 ft ( 9 m) (maximum) vertical mast (interlocking tubing sections) held in place by guy ropes & ground stakes Ht of assembled equipt to highest pt varies from 37 ft (11 m) to 41.5 ft (12.45 m) ©LTCOL G.R. Newman-Martin 2011
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©LTCOL G.R. Newman-Martin 2011
RC-292 Antenna equipment Demountable antenna system designed to increase range of Radio Set AN/PRC-77 Elevated mast-mounted ground plane antenna. Omni-directional Antenna can be elevated on 30 ft ( 9 m) (maximum) vertical mast (interlocking tubing sections) held in place by guy ropes & ground stakes Ht of assembled equipt to highest pt varies from 37 ft (11 m) to 41.5 ft (12.45 m) Weighs 48 pounds (21.8 kg) complete ©LTCOL G.R. Newman-Martin 2011
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©LTCOL G.R. Newman-Martin 2011
RC-292 Antenna equipment Demountable antenna system designed to increase range of Radio Set AN/PRC-77 Elevated mast-mounted ground plane antenna. Omni-directional Antenna can be elevated on 30 ft ( 9 m) (maximum) vertical mast (interlocking tubing sections) held in place by guy ropes & ground stakes Ht of assembled equipt to highest pt varies from 37 ft (11 m) to 41.5 ft (12.45 m) Weighs 48 pounds (21.8 kg) complete Can be carried by two pers in special pack ©LTCOL G.R. Newman-Martin 2011
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©LTCOL G.R. Newman-Martin 2011
RC-292 Antenna equipment Demountable antenna system designed to increase range of Radio Set AN/PRC-77 Elevated mast-mounted ground plane antenna. Omni-directional Antenna can be elevated on 30 ft ( 9 m) (maximum) vertical mast (interlocking tubing sections) held in place by guy ropes & ground stakes Ht of assembled equipt to highest pt varies from 37 ft (11 m) to 41.5 ft (12.45 m) Weighs 48 pounds (21.8 kg) complete Can be carried by two pers in special pack Can be set up by 2 pers in 15 mins ©LTCOL G.R. Newman-Martin 2011
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©LTCOL G.R. Newman-Martin 2011
RC-292 Antenna equipment VERTICAL ELEMENT (ONE, TWO,OR THREE MAST SECTIONS AB-21/GR, AND ONE EACH OF MAST SECTIONS AB-22/GR, AB-23/GR, AND AB-24/GR ANTENNA BASE MP-68 GROUND PLANE ELEMENT (ONE, TWO,OR THREE MAST SECTIONS AB-21/GR, AND ONE EACH OF MAST SECTIONS AB-22/GR, AB-23/GR, AND AB-24/GR, PER ELEMENT TAPE Antenna part comprises: ©LTCOL G.R. Newman-Martin 2011
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©LTCOL G.R. Newman-Martin 2011
RC-292 Antenna equipment VERTICAL ELEMENT (ONE, TWO,OR THREE MAST SECTIONS AB-21/GR, AND ONE EACH OF MAST SECTIONS AB-22/GR, AB-23/GR, AND AB-24/GR ANTENNA BASE MP-68 GROUND PLANE ELEMENT (ONE, TWO,OR THREE MAST SECTIONS AB-21/GR, AND ONE EACH OF MAST SECTIONS AB-22/GR, AB-23/GR, AND AB-24/GR, PER ELEMENT TAPE Antenna part comprises: antenna base ©LTCOL G.R. Newman-Martin 2011
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©LTCOL G.R. Newman-Martin 2011
RC-292 Antenna equipment VERTICAL ELEMENT (ONE, TWO,OR THREE MAST SECTIONS AB-21/GR, AND ONE EACH OF MAST SECTIONS AB-22/GR, AB-23/GR, AND AB-24/GR ANTENNA BASE MP-68 GROUND PLANE ELEMENT (ONE, TWO,OR THREE MAST SECTIONS AB-21/GR, AND ONE EACH OF MAST SECTIONS AB-22/GR, AB-23/GR, AND AB-24/GR, PER ELEMENT TAPE Antenna part comprises: antenna base one vertical radiating antenna element ©LTCOL G.R. Newman-Martin 2011
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©LTCOL G.R. Newman-Martin 2011
RC-292 Antenna equipment VERTICAL ELEMENT (ONE, TWO,OR THREE MAST SECTIONS AB-21/GR, AND ONE EACH OF MAST SECTIONS AB-22/GR, AB-23/GR, AND AB-24/GR ANTENNA BASE MP-68 GROUND PLANE ELEMENT (ONE, TWO,OR THREE MAST SECTIONS AB-21/GR, AND ONE EACH OF MAST SECTIONS AB-22/GR, AB-23/GR, AND AB-24/GR, PER ELEMENT TAPE Antenna part comprises: antenna base one vertical radiating antenna element three ground plan elements at angle of 142º to vertical element ©LTCOL G.R. Newman-Martin 2011
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©LTCOL G.R. Newman-Martin 2011
RC-292 Antenna equipment VERTICAL ELEMENT (ONE, TWO,OR THREE MAST SECTIONS AB-21/GR, AND ONE EACH OF MAST SECTIONS AB-22/GR, AB-23/GR, AND AB-24/GR ANTENNA BASE MP-68 GROUND PLANE ELEMENT (ONE, TWO,OR THREE MAST SECTIONS AB-21/GR, AND ONE EACH OF MAST SECTIONS AB-22/GR, AB-23/GR, AND AB-24/GR, PER ELEMENT TAPE Antenna part comprises: antenna base one vertical radiating antenna element and three ground plan elements at angle of 142º to vertical element. Elements can be adjusted in length by adding or subtracting metal tubing sections. ©LTCOL G.R. Newman-Martin 2011
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©LTCOL G.R. Newman-Martin 2011
QUESTIONS? ©LTCOL G.R. Newman-Martin 2011
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