1 Antennas of Field Day Main High Frequency Antennas from the 2009 LARC FARL Field Day Ford Amateur Radio League David Treharne, N8HKU January, 2010
2 The Antennas The G5RV wire dipole: 80m 10m The Carolina Windom: 80m 10m The Cushcraft R7 Vertical: 40m 10m Not Covered: Inverted L: did not make many contacts, it was not working as it should. Satellite antenna
3 Site Layout
4 G5RV Antenna Wire Dipole antenna, 51 ft per side, 102 ft long, ft matching section made of ladder line. Line isolator or balun at the bottom to isolate the coax from the matching section Developed by Louis Varney, G5RV, as a multiband antenna that could fit in the yard of an English residence. Resonant on 20m, needs a tuner for all other bands. Most effective on 80, 40, 20, 15, and 10. Bad on 30m and 17m.
5 Physical dimensions Can be installed as a flat top, a Vee, and the two legs at an angle from 120 degrees to 180 degrees.
6 How it Works The matching section makes the antenna load look better on 80m, even though it it short. The matching section makes the antenna match close on 40m The matching section makes the antenna load look like 50 ohms resistive on 20m.
7 Higher frequencies Multiple wavelengths on 15m, resistive at the bottom. Multiple wavelengths on 10m, resistive and reactive at the bottom.
8 Radiation Angles As expected, the radiation pattern changes with frequency and with height. All of these graphs are with the antenna about 34 ft from the ground. The center of our Field Day set up was about 35 ft high, with one end about 50ft, and the other end less than 30 ft. When is a dipole NOT a dipole? Answer: When it is less than ½ wavelength long.
9 80m G5RV Radiation Elevation: Best radiation is straight up: A cloud warmer that is good for local contacts. Horizon The antenna radiates off the almost as good as broadside. The antenna wire is parallel with the 0 deg line. Antenna
10 20m G5RV Best takeoff angle is 24 degrees, better for long distance. At 24 degrees take off angle, nulls at 22 degrees, and best at 52 degrees from antenna face, 7.7 dbi better than an isotropic radiator. (A perfect dipole is 2.1dBi better) Antenna 22 degrees
11 15m G5RV Good long distance take off. The antenna gets a lot of sharp nulls due to the multiple wavelengths, particularly across the face. Best performance is at 30 degrees from the face, 9.8dBi better than an isotropic radiator.
12 Windom Wire Dipole 133ft long for 80-10m Not fed in the center, but fed approximately 1/3 from one end. The original windom was a single wire, with a good ground system serving as the other side. With a balun transformer at the 1/3 point, the antenna became a dipole. The antenna is harmonically resonant, making it good for the harmonic amateur bands, not good at other frequencies.
13 Windom Antenna (Buckmaster) This antenna is good at 75/80m, 40m, 20m, and 10m, also 6m. It is pretty good at 17m and 12m, but not good at 30m nor at 15m. A classic windom is not recommended to be operated on 15m, even with an antenna tuner. The ferrite balun at the 1/3 point will overheat and damage the antenna.
14 Carolina Windom A variation on the Windom antenna, developed 25 years ago or so to help make a Windom work better on 75m over a North Carolina to Virginia communication path. Makes use of ladder line like a G5RV does. Inserts a matching network of ladder line down from the transformer at the 1/3 point of the antenna. Inserts a balun or isolator at the bottom of the ladder line to coax.
15 RadioWorks Carolina Windom Antenna is longer than a G5RV Similar gain to a G5RV at higher frequencies: Better at 80 and 40 due to increased length? High power transformer and isolator allows an antenna tuner to match it on non resonant frequencies such as 30m and 15m. Vertical radiator probably works similar to G5RV as a wavelenght matching network.
16 Carolina Windom Radiation Pattern Article from RadioWorks indicates that the vertical portion of the antenna does indeed radiate and make the antenna perform at multiple vertical angles. If true, then it will have less gain at the lower angles for longer distances, and it will also pick up more noise. It will be able to handle intermediate distances better than a dipole. There have been some articles comparing the noise of this antenna versus a dipole, and found it 1 s unit noisier.
17 SWR Carolina Windom SWR 4 Carolina Windom Carolina Windom courtesy of Dan Parks. WT8F Jan, Frequency (khz) Not as good of SWR as a Windom, but tunable via an antenna tuner.
18 80M; G5RV and Carolina Windom Note on the comparison: The G5RV worked SSB, the Carolina Windom worked CW. Direct comparisons are difficult given the 2.3kHz bandwidth of SSB versus 60 Hz for CW. The Windom got a wider initial range and a double skip to CA, the G5RV only a single skip. Both antennas made contacts broadside and off the ends, like the radiation pattern indicated it would.
19 40M; G5RV and Carolina Windom The Windom got good moderate distance range to Indiana and Ohio, and better to the Southwest. The G5RV did better to the Northwest part of the US
20 20M; G5RV and Carolina Windom Here, the G5RV also had better performance to the Northwest US and western Canadian provinces. The G5RV also had slightly better near in coverage and east coast coverage. Both antennas still got signals off the ends of the antenna.
21 15M; G5RV and Carolina Windom Both antennas now have predominantly low angles of radiation, and pretty well defined skip zones. The G5RV contacts are all within a single skip zone, the Carolina Windom has two skip zones defined. The Windom still worked some off the end of the antenna, but better off of the side.
22 10M; G5RV and Carolina Windom No contacts made by the G5RV, and a single skip distance by the Windom, off angle to the direction of the antenna, consistent with a multiple wavelength dipole antenna.
23 Cushcraft R7 Vertical Trap vertical antenna for 40m, 30m, 20m, 17m, 15m, 12m and 10m 22.5 ft tall (6.9m), 100 in wide from counterpoise end to end Acts like a dipole antenna, so no ground radials are required. Antenna is vertically polarized. Uses capacitive hats for resonance loading along with the traps Uses a matching network for the coax to the antenna.
24 Cushcraft R7 Vertical Vertically polarized antennas generally transmit a low angle of radiation toward the horizon. (locating this antenna 50ft + above ground may have added some high angle (short skip) lobes. The wire antennas were horizontally polarized, making this antenna coexist well with the other two antennas This antenna is electrically extremely short, therefore has a poor radiation resistance. The resistance of the L and C in the matching network and traps consumes a lot of the power. Because this antenna does not need a system of ground radials, it can be mounted significantly above ground, which we took advantage of by locating the antenna at the top of the antenna tower.
25 Cushcraft R7 Vertical Antenna is tuned from the highest frequency (10m) down to the lowest frequency by adjusting the various distances between traps. Note that one must choose the part of the 40m band to cover. This was not done before assembling this antenna for the 2009 Field Day, resulting in a low frequency resonance that could not be modified even with an antenna tuner. All other bands functioned in the SSB area without the need of an antenna tuner.
26 Cushcraft R7 Vertical 40 meter tuning section A Trap: A L-C tuned circuit that looks high impedance at its resonant point, and inductive at lower frequencies. A Trap cuts off the antenna beyond its resonant frequency, and adds electrical length to the antenna at lower frequencies. Capacitive hat 30 meter trap 20 meter trap 17 meter trap 15meter trap Capacitive hat 10 meter radiating section Counterpoise (eliminates ground radials) Matching section (mostly inductance)
27 20M; R7 and G5RV Comparing the R7 and G5RV since both operated SSB Good east-west coverage on the R7, as well as some north and south. R7 picked up some Southwestern states missed by the G5RV, and was the only Alaska contact!
28 15M; R7 and Carolina Windom Used the Carolina Windom here because it had more contacts. The R7 vertical did work Idaho and Western Washington that were missed by the Windom. Good single and double skip coverage, and some short skip (Wisconsin and Ohio) that was not made by the wire antennas.
29 10M; R7 and Carolina Windom R7 made a few contacts here. The entire band was not open much due to the sunspot cycle.
30 Conclusions Both the G5RV and Carolina Windom antennas worked very well on multiple bands, and showed omnidirectional capability at the lower frequencies, indicating our positioning of them 90 degrees from one another did not cause any disadvantages. Both antennas had good performance at the higher frequencies, but both had blind zones. The R7 vertical did very well for its size, and was advantaged by placing it high, perhaps improving both long range and short skip or ground plane performance.
Introduction to Antennas Dipoles Verticals Large Loops Yagi-Uda Arrays by Marc C. Tarplee Ph.D., NCE N4UFP Introduction What is an antenna? An antenna is a device that: Converts RF power applied to its
Basic Wire Antennas Part II: Loops and Verticals A loop antenna is composed of a single loop of wire, greater than a half wavelength long. The loop does not have to be any particular shape. RF power can
Just a Dipole Gary Wescom N0GW July 16, 2007 Often we will hear people describing their antennas as just a dipole. After all, a coax cable fed, half wavelength dipole is one of the simplest antennas to
Antennas A good antenna works A bad antenna is a waste of time & money Antenna systems can be very inexpensive and simple They can also be very, very expensive Antenna Considerations The space available
Presenters: Slides 1 thru 39 Harold AD7QJ Slides 40 thru 49 Mike KD7GHZ 1 VHF Club November Meeting Presentation HF Antennas for Portable Operation 2 Basic Long Wire Transceiver Antenna Tuner Long wire
66.5 ft (20.27m) 66.5 ft (20.27m) Note:- Half Size Doublet covering the 40m-10m bands 51 ft (16m) 450 Ohm Balanced Tuner Doublets can use either 450 ohm ladder-line for his feeder back to the shack but
Technician Licensing Class Antennas Presented by Amateur Radio Technician Class Element 2 Course Presentation ELEMENT 2 SUB-ELEMENTS (Groupings) About Ham Radio Call Signs Control Mind the Rules Tech Frequencies
Antennas 101 Eric Hansen, KB1VUN How does radio work? Transmitter: Convert message to radio frequency (RF) voltage Antenna: Convert RF to propagating electromagnetic (EM) wave Propagation path Antenna:
ZS6BKW vs G5RV Antenna Patterns/SWR at 40 ft Center height, 27 ft end height ~148 Degree Included Angle Compiled By: Larry James LeBlanc 2010 For the AARA Ham Radio Club Note: All graphs computed using
A Ten Meter Vertical Antenna for All License Classes by Rich KR7W The intent of this article is to show how I built an effective 10 meter vertical antenna. My goal is to reveal, in some kind of logical
Our low profile MLA series Miniloops and very low profile MLH series half loops are high power communications antennas. These antennas are designed for installation in virtually any environment, especially
The 3-D Folded Loop Antenna Dave Cuthbert WX7G Introduction This article will introduce you to an antenna I call the 3-Dimensional Folded Loop. This antenna is the result of my continuing efforts to compact
A Broadband 80/160 Meter Dipole An easy to build single wire antenna for 160 and 80 meters with a better than 2 to 1 swr across the 80 meter band. by Gene Preston, K5GP I read Rick Littlefield s article
Jan. 17, 2008 VE3MLB Phased Double V Antenna for 75/80 Meter Band This is a story of a double inverted V antenna that I built in January 2008. I already had a full 80 meter Delta loop suspended from my
HF Antennas 101 SARA Monthly Meeting 3/3/2010 Dave Ritchie, W6DR Yin Shih, N9YS HF Antennas 101 A good antenna may be the most important component of a good HF station 1W QRP station + good antenna can
Selecting Receiving Antennas for Radio Tracking Larry B Kuechle, Advanced Telemetry Systems, Inc. Isanti, Minnesota 55040 email@example.com The receiving antenna is an integral part of any radio location
Contesting and DX Antennas for Restricted Lots by Dick Weber, K5IU DWEBTX@yahoo.com The goal of this presentation is to provide information so you can make reasonable fact based decisions / choices. Caution:
This simple broad band antenna is easy to build, has gain similar to that of a dipole and is tolerant of nearby objects. It can be erected in almost any configuration provided the wires are well separated
M3KXZ Portable Double-T Vertical for 20 thru 6m Introduction I was inspired by the discussions on the Verticals-2 Yahoo group about double-t antennas for the lower HF bands. A double-t is a top and bottom
The G5RV Antenna System -- An Analysis Rick Hiller W5RH The G5RV Legacy Old Wives Tales Urban Myths Repeater QSO s spread: Lies Half-truths Falsehoods. The truth, the whole truth and nothing but the truth..so
Portable HF Antennas Presented to the Stamford Amateur Radio Association by Jon Perelstein Copyright 2010 Jon Perelstein 1 For purposes of this presentation, a portable HF antenna is An antenna that doesn't
Newcomers and Elmers Net: More Wire Antennas 02.14.16 Robert AK3Q Antenna Construction Supplies Antenna Construction Tools (Harbor Freight can be a good place to go) Wire Cutters; Pliers (regular and needle
Modeling an 80/40/20M Fan Dipole for DX New Station New Antennas! Installation and SWR Response Where is the DX? How do these Dipoles Play? (EZNEC) What about Terrain? HFTA and Terrain The effect on these
160m/80m Broadband Antenna by K5GP A presentation to CTDXCC September 22, 2008 The 160m/80m broadband antenna design objectives were to have: 160 and 80 m antennas since I had no antennas for these bands,
Newcomers and Elmers Net 7-7-13: Basic Antenna Theory Radio Waves Radio waves are a combination of both an electric field and a magnetic field traveling perpendicular to one another at roughly the speed
Printed Omni Directional Wi-Fi Antenna for 5.6 GHz Dragoslav Dobričić, YU1AW firstname.lastname@example.org Why printed antenna? Building antenna on SHF is associated with problems of manufacturing its parts with
Broadband Terminated Vee Beam Wire Antenna TEN-TEC Model 3402 and 3403 1.8-54 or 3.5-54 MHz. THROW AWAY YOUR ANTENNA TUNER! Models 3402 and 3403 are broadband terminated vee beam wire antennas. These broadband
TECHNOTE No. 1 Joe Carr's Radio Tech-Notes Directional or Omnidirectional Antenna? Joseph J. Carr Universal Radio Research 6830 Americana Parkway Reynoldsburg, Ohio 43068 1 Directional or Omnidirectional
Sigma-40XK A closer look at Force 12 s 10-40 meter vertical dipole T his antenna was a first for me. Except for a couple of Hamsticks, all of my antennas are homebrew. I m always looking for antennas that
ANTENNA An antenna is a device to transmit and/or receive electromagnetic waves. Electromagnetic waves are often referred to as radio waves. Most antennas are resonant devices, which operate efficiently
Constructing and Using Chokes The first installment of this series introduced basic antenna modeling and demonstrated the generation and control of feed line currents. The control of the feed line currents
The Care and Feeding of Simple, Broadband HF Antennas Tom McDermott, N5EG March 3, 2011 Problem Statement 1. Cover multiple HF Amateur Bands with one antenna. 80m through 10m if possible. 2. Use single
INTRODUCTION MFJ-1756 6 METER GROUND PLANE ANTENNA The MFJ-1756 Ground Plane Antenna features a DC grounded element and a ground isolated radial system for improved performance. The ground isolated radial
Small HF Antennas! The Small Space and Big Antenna Dilemma! Constraints " Covenants " Restricted lot size " City Bylaws " Boards of Variance " Strata Rules " Neighbor complaints of unsightly structures
BASIC ANTENNAS FOR EXPERIMENTERS If you ever experiment with receivers and/or transmitters, you will at some point need to consider the subject of antennas. This is a very large subject and could occupy
Antenna Properties and their impact on Wireless System Performance Dr. Steven R. Best Cushcraft Corporation 48 Perimeter Road Manchester, NH 03013 Phone (603) 627-7877 FAX: (603) 627-1764 Email: email@example.com
The Villages Amateur Radio Club 2015 Antenna Guide for The Villages 1 Antennas for The Villages Tonight's review of the antenna members have used Tonight's list of antennas will cover Multiband Antennas
Cross Country Wireless (2009) Ltd, 7 Thirlmere Grove, BOLTON, BL4 0QB, UK Email firstname.lastname@example.org Web page http://www.crosscountrywireless.net Telephone +44 (0) 1204 410626 Mobile GSM 900
Antenna Basics Introduction Antennas are a very important component of communication systems. By definition, an antenna is a device used to transform an RF signal, traveling on a conductor, into an electromagnetic
Installation Instructions Hustler 6-BTV Trap Vertical ASSEMBLY 1. Check the package contents against the parts list on page 2. 2. WARNING. Installation of this product near power lines is dangerous. For
The W5JCK Guide to the Mathematic Equations Required for the Amateur Extra Class Exam This document contains every question from the Extra Class (Element 4) Question Pool* that requires one or more mathematical
HF Tactical NVIS ANTENNAS Introduction: A properly designed Near Vertical Incident Skywave (NVIS) antenna will have a directivity pattern that will maximize transmission and reception at high angles while
Introduction The MFJ-989D roller inductor tuner is a 1500 watt CW antenna tuner which handles the US amateur legal limit. This power rating is for load impedances of 12.5-3200 ohms. The MFJ-989D is designed
Model MFJ-706 INSTRUCTION MANUAL CAUTION: Read All Instructions Before Operating Equipment MFJ ENTERPRISES, INC. 300 Industrial Park Road Starkville, MS 39759 USA Tel: 662-323-5869 Fax: 662-323-6551 VERSION
Regional Emergency Communications John Walters W8CX Alpena RACES Regional Communications Needs 400 mile radius No skip zone; no dead spots No interference with or from broadcasters Reliable day/night coverage
Antenna Selection for Optimum Wireless LAN Performance Dr. Steven R. Best Cushcraft Corporation 48 Perimeter Road Manchester, NH 03108 (603) 627-7877 PURPOSE Overview of antenna properties and performance
Wire Antennas for Ham Radio 70 Antenna Ideas Iulian Rosu YO3DAC / VA3IUL, http://www.qsl.net/va3iul 1 de 45 Summary 1. Tee Antenna 4 2. Half-Lamda Tee Antenna 4 3. Twin-Led Marconi Antenna 5 4. Swallow-Tail
By Ron Bertrand VK2DQ - 2007 Want to build a simple, efficient, multiband antenna? One of the best and inexpensive multiband antennas is the off-centre-fed (OCF) dipole. These are wonderfully simple antennas
Stephen E. Sussman-Fort, Ph.D. AB2EW email@example.com Outline Brief History Characteristics of Small Loop Antennas for HF My Loop for 40m 15m Receive/Transmit Properties of Elect.-Small Loops Loop
40 Meter Mini-MOXON Beam Antenna Designed, built, and presented by: Al Koblinski W7XA Design goals Some forward gain Good directivity (high F/B and F/S ratios) Relatively small size Good Bandwidth (min.
3.2.1. Circuit Modeling: Loop Impedance A loop antenna can be represented by a lumped circuit when its dimension is small with respect to a wavelength. In this representation, the circuit parameters (generally
Efficient 2 meter Disguise Antenna Made From a TV Satellite Dish This horizontal slot antenna, cut into the reflector of a TV dish, is both the master of disguise and high in performance. By John Portune
General Info on Baluns Baluns: Choosing the Correct Balun By Tom, W8JI Balun is an acronym for BALanced to UNbalanced, which describes certain circuit behavior in a transmission line, source or load. Most
How to construct a very small but efficient Antenna with PVC Plumbing tube and discarded fruit cans. - Just the thing to fit in a small space such as the house attic (Also published in the Australian journal
Long-Wire Antennas The Off-Center Fed Long Wire An antenna is only a long wire if it is one wavelength or greater overall. A physically long piece of wire does not constitute a "long wire," contrary to
Owners Manual For The PackTenna Mini By Nick Garner N3WG and George Zafiropoulos KJ6VU Quickstart With The 9:1 Random Wire Version You can identify this version because it has a yellow shrink wrap on the
7.4 Slotted-cylinder antennas As illustrated in Figure 7-3, a slot in an infinite plane is equivalent to a dipole of the same dimensions. In practice, a sheet much bigger than the slot is a nearly infinite
1 San Jose State University EE 172 - Microwave Dr. Ray Kwok by Hanbo Tao May 25 th, 2011 2 Abstract This report will explain the theory of dipole antenna, and a 2x2 half wave dipole antenna will be designed
Antenna Trainer EAN Technical Teaching Equipment Products Products range Units 3.-Communications INTRODUCTION Antennas are the main element of aerial communications. They are the transition between a transmission
EE302 Lesson 14: Antennas Loaded antennas /4 antennas are desirable because their impedance is purely resistive. At low frequencies, full /4 antennas are sometime impractical (especially in mobile applications).
M2 Antenna Systems, Inc. Model No: PS-2M SPECIFICATIONS: Model... PS-2M Frequency Range... 100 to 250 MHz Isolation, 2M / 440... 50 db / 40 db Feed Impedance.... 50 Ohms Unbalanced VSWR... 1.2:1 or better
Coaxial Cable Feeder Influence on Yagi Antenna Dragoslav Dobričić, YU1AW firstname.lastname@example.org Introduction o far, in several previous articles [1, 2, 3], we investigated how boom radius and its S distance
Module 9 AC Theory LCR Series Circuits Introduction to LCR Series Circuits What you'll learn in Module 9. Module 9 Introduction Introduction to LCR Series Circuits. Section 9.1 LCR Series Circuits. Amazing
Study of RF Spectrum Emissions in High Pressure Sodium and Metal Halide Lamps Lawrence P. Glaister VE7IT, Automation Engineer May 2010 Abstract: This research was performed in collaboration with the City
NATIONAL TYPE MB-40SL MULTI-BAND TANK 9/29/1953 1. GENERAL The MB-40SL tanks is intended for use in grid circuits with approximately 20 Watts input and in final plate tank circuits of transmitters when
My Top Five Backyard Multi-Band Wire HF Antennas L. B. Cebik, W4RNL 1434 High Mesa Drive Knoxville, TN 37938-4443 e-mail: email@example.com 2004 marks my fifth full decade as a licensed radio amateur. So
Single Transistor FM Transmitter Design In telecommunications, frequency modulation (FM) conveys information over a carrier wave by varying its frequency. FM is commonly used at VHF radio frequencies for
Chapter 13 Long Wire and Traveling Wave Antennas The power gain and directive characteristics of the harmonic wires (which are long in terms of wavelength) described in Chapter 2 make them useful for long-distance
EMC STANDARDS The EMC standards that a particular electronic product must meet depend on the product application (commercial or military) and the country in which the product is to be used. These EMC regulatory
Avaya WLAN 9100 External Antennas for use with the WAO-9122 Access Point Overview To optimize the overall performance of a WLAN in an outdoor deployment it is important to understand how to maximize coverage
ISS Minimalist Antenna The purpose of this project was to develop an antenna suggestion that would allow for a simple to duplicate, affordable antenna solution for reasonable access to signals transmitted
Multi-band HF Antennas Part 3 VA3TPV Every now and again during research for background material for RSARS e-library articles, a new source of really well written articles is discovered. The Mississauga
"EGGBEATER"ANTENNA VHF/UHF ~ PART 1 ON6WG / F5VIF For the enthusiastic listeners or the licensed amateur station wishing to experiment with satellite transmissions without investing a large sum of money