Wire Antennas for Ham Radio
Total Page：16
File Type：pdf, Size：1020Kb
Load more
Recommended publications
-
High Frequency Communications – an Introductory Overview
High Frequency Communications – An Introductory Overview - Who, What, and Why? 13 August, 2012 Abstract: Over the past 60+ years the use and interest in the High Frequency (HF -> covers 1.8 – 30 MHz) band as a means to provide reliable global communications has come and gone based on the wide availability of the Internet, SATCOM communications, as well as various physical factors that impact HF propagation. As such, many people have forgotten that the HF band can be used to support point to point or even networked connectivity over 10’s to 1000’s of miles using a minimal set of infrastructure. This presentation provides a brief overview of HF, HF Communications, introduces its primary capabilities and potential applications, discusses tools which can be used to predict HF system performance, discusses key challenges when implementing HF systems, introduces Automatic Link Establishment (ALE) as a means of automating many HF systems, and lastly, where HF standards and capabilities are headed. Course Level: Entry Level with some medium complexity topics Agenda • HF Communications – Quick Summary • How does HF Propagation work? • HF - Who uses it? • HF Comms Standards – ALE and Others • HF Equipment - Who Makes it? • HF Comms System Design Considerations – General HF Radio System Block Diagram – HF Noise and Link Budgets – HF Propagation Prediction Tools – HF Antennas • Communications and Other Problems with HF Solutions • Summary and Conclusion • I‟d like to learn more = “Critical Point” 15-Aug-12 I Love HF, just about On the other hand… anybody can operate it! ? ? ? ? 15-Aug-12 HF Communications – Quick pretest • How does HF Communications work? a. -
ZS6BKW Vs G5RV Antenna
ZZS6BS6BKWKW vsvs G5RG5RVV 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 MMANA GAL http://mmhamsoft.amateur-radio.ca/mmana/index.htm ZSZS6BK6BKWW // G5RVG5RV WhaWhatt isis it?it? In the mid-1980s, Brian Austin (ZS6BKW) ran computer analysis to develop an antenna System that, for the maximum number of HF bands possible, would permit a low Standing Wave Ratio (SWR) without antenna tuner to interface with a 50-Ohm coaxial cable as the main feed line. He identified a range of lengths which, when combined with a matching ladder line length, would provide this characteristic. According to an acknowledged expert in computer antenna design and modeling, L. B. Cebik: “Of all the G5RV antenna system cousins, the ZS6BKW antenna system has come closest to achieving the goal that is part of the G5RV mythology: a multi-band HF antenna consisting of a single wire and simple matching system to cover as many of the amateur HF bands as possible.” Both are “good” antennas and will work well in defined situations. This presentation is not designed to “bash” the G5RV, but to possibly convince you or a new ham to enjoy the benefits of lower SWR, lower loss, and greater signal strength by using the ZS6BKW version of a ladder line fed dipole. ZZSS66BBKWKW // GG55RRVV WWhhyy II liklikee itit 1. Has low swr in several ham bands at the matching point at the end of the ladder line resulting in lower losses in the coax cable. -
The G5rv Antenna
SUCCESSFUL WIRE ANTENNAS Band (metres) 80 40 30 20 17 15 12 10 6 2 L1 end (2) 168 89.4 63.2 45 35.3 30 25.6 22.4 12.7 4.37 L2 centre (2) 65 34.7 24.6 17.5 13.7 11.7 9.97 8.72 4.95 1.70 L3 total size 467 248 176 125 98 83.3 71.2 62.3 35.4 12.2 L4 stubs 48.6 25.8 18.3 13 10.2 8.66 7.4 6.47 3.68 1.26 L5 height 120 64 45 32 25 21 18 16 10 10 Inductor (μH) 25.9 11.7 7.3 4.9 3.4 2.8 2.2 1.9 0.85 0.13 Gain (dBi) 11.4 11.4 11.3 11.2 11.1 11.0 11.0 11.0 11.4 10.9 Freq (MHz) 3.8 7.15 10.1 14.2 18.12 21.3 24.93 28.5 50.2 146 Table 4.3: Lengths (in feet) of an HGSW beam for 10 amateur bands. insulators as shown. The lower ends of the two lines should be stripped and bent over and soldered together. The resultant active line length must be 13ft. The dis- tance from the centre insulator to the ladder line should be 17.5ft. If you have a lot of wind in your area you might want to tie a 1oz lead fishing sinker to the bottom of each of the phasing lines. Alternately a string can be attached and tied to some secure point below the antenna. -
An Electrically Small Multi-Port Loop Antenna for Direction of Arrival Estimation
c 2014 Robert A. Scott AN ELECTRICALLY SMALL MULTI-PORT LOOP ANTENNA FOR DIRECTION OF ARRIVAL ESTIMATION BY ROBERT A. SCOTT THESIS Submitted in partial fulfillment of the requirements for the degree of Master of Science in Electrical and Computer Engineering in the Graduate College of the University of Illinois at Urbana-Champaign, 2014 Urbana, Illinois Adviser: Professor Jennifer T. Bernhard ABSTRACT Direction of arrival (DoA) estimation or direction finding (DF) requires mul- tiple sensors to determine the direction from which an incoming signal orig- inates. These antennas are often loops or dipoles oriented in a manner such as to obtain as much information about the incoming signal as possible. For direction finding at frequencies with larger wavelengths, the size of the array can become quite large. In order to reduce the size of the array, electri- cally small elements may be used. Furthermore, a reduction in the number of necessary elements can help to accomplish the goal of miniaturization. The proposed antenna uses both of these methods, a reduction in size and a reduction in the necessary number of elements. A multi-port loop antenna is capable of operating in two distinct, orthogo- nal modes { a loop mode and a dipole mode. The mode in which the antenna operates depends on the phase of the signal at each port. Because each el- ement effectively serves as two distinct sensors, the number of elements in an DoA array is reduced by a factor of two. This thesis demonstrates that an array of these antennas accomplishes azimuthal DoA estimation with 18 degree maximum error and an average error of 4.3 degrees. -
High Frequency (HF)
Calhoun: The NPS Institutional Archive Theses and Dissertations Thesis Collection 1990-06 High Frequency (HF) radio signal amplitude characteristics, HF receiver site performance criteria, and expanding the dynamic range of HF digital new energy receivers by strong signal elimination Lott, Gus K., Jr. Monterey, California: Naval Postgraduate School http://hdl.handle.net/10945/34806 NPS62-90-006 NAVAL POSTGRADUATE SCHOOL Monterey, ,California DISSERTATION HIGH FREQUENCY (HF) RADIO SIGNAL AMPLITUDE CHARACTERISTICS, HF RECEIVER SITE PERFORMANCE CRITERIA, and EXPANDING THE DYNAMIC RANGE OF HF DIGITAL NEW ENERGY RECEIVERS BY STRONG SIGNAL ELIMINATION by Gus K. lott, Jr. June 1990 Dissertation Supervisor: Stephen Jauregui !)1!tmlmtmOlt tlMm!rJ to tJ.s. eave"ilIE'il Jlcg6iielw olil, 10 piolecl ailicallecl",olog't dU'ie 18S8. Btl,s, refttteste fer litis dOCdiii6i,1 i'lust be ,ele"ed to Sapeihil6iiddiil, 80de «Me, "aial Postg;aduulG Sclleel, MOli'CIG" S,e, 98918 &988 SF 8o'iUiid'ids" PM::; 'zt6lI44,Spawd"d t4aoal \\'&u 'al a a,Sloi,1S eai"i,al'~. 'Nsslal.;gtePl. Be 29S&B &198 .isthe 9aleMBe leclu,sicaf ,.,FO'iciaKe" 6alite., ea,.idiO'. Statio", AlexB •• d.is, VA. !!!eN 8'4!. ,;M.41148 'fl'is dUcO,.Mill W'ilai.,s aliilical data wlrose expo,l is idst,icted by tli6 Arlil! Eurse" SSPItial "at FRIis ee, 1:I.9.e. gec. ii'S1 sl. seq.) 01 tlls Exr;01l ftle!lIi"isllatioli Act 0' 19i'9, as 1tI'I'I0"e!ee!, "Filill ell, W.S.€'I ,0,,,,, 1i!4Q1, III: IIlIiI. 'o'iolatioils of ltrese expo,lla;;s ale subject to 960616 an.iudl pSiiaities. -
The 3-D Folded Loop Antenna
The 33---DD 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 full-size antennas by folding and bending the elements. I will first describe the basic 3-DFL and then provide construction details for the 2-meter and 10-meter 3-DFL antennas. Here are some features of the 3-DFL: • Reduced height and footprint • Full-sized antenna performance • Wide bandwidth • Ground independent • Can be built using standard hardware store parts Description The 3-D Folded Loop, or simply the 3-DFL, is a one-wavelength loop that is reduced in height and width by being folded into three dimensions. A 28-MHz loop that is normally 9 feet on a side becomes a box-shaped antenna that is 3 by 3 by 5 feet. It exhibits performance that is competitive with a ground plane yet requires only 15 square feet of ground area versus 50 for the ground plane. So, compared to a ground plane it is only 60% as tall and has a footprint only 30% as large. And the 2-meter 3-DFL is so compact it can be placed on a table and connected to your HT for added range and reduced RF at the operating position. 1 3-DFL Theory of Operation The familiar one-wavelength square loop is shown in Fig. 1 and is fed in the center of one vertical wire. Note that the current in the vertical wires is high while the current in the horizontal wires and is low. -
Proceedings, ITC/USA
International Telemetering Conference Proceedings, Volume 18 (1982) Item Type text; Proceedings Publisher International Foundation for Telemetering Journal International Telemetering Conference Proceedings Rights Copyright © International Foundation for Telemetering Download date 09/10/2021 04:34:04 Link to Item http://hdl.handle.net/10150/582013 INTERNATIONAL TELEMETERING CONFERENCE SEPTEMBER 28, 29, 30, 1982 SPONSORED BY INTERNATIONAL FOUNDATION FOR TELEMETERING CO-TECHNICAL SPONSOR INSTRUMENT SOCIETY OF AMERICA Sheraton Harbor Island Hotel and Convention Center San Diego, California VOLUME XVIII 1982 1982 INTERNATIONAL TELEMETERING CONFERENCE Ed Bejarano, General Chairman Robert Klessig, Vice Chairman Norman F. Lantz, Technical Program Chairman Gary Davis, Vice Technical Chairman Alain Hackstaff, Exhibits Chairman Warren Price, Publicity Chairman Burton E. Norman, Finance Chairman Francis X. Byrnes, Local Arrangements Chairman Fran LaPierre, Registration Chairman Bruce Thyden, Golf Tournament Technical Program Committee: Lee H. Glass Karen L. Billings BOARD, INTERNATIONAL FOUNDATION FOR TELEMETERING H. F. Pruss, President W. W. Hammond, Vice-President D. R. Andelin, Asst. Secretary & Treasurer R. D. Bently, Secretary B. Chin, Director F. R. Gerardi, Director T. J. Hoban, Director R. Klessig, Director W. A. Richardson, Director C. Weaver, Director 1982 ITC/USA Program Chairman Norman F. Lantz Program Chairman The conference theme this year is “Systems and Technology in the ’80’s: Expanding Horizons.” It was selected to continue the theme which began with ITC/USA ’80. The technological advances that have occurred over the past decade have, and continue to have, a profound affect on the nature and applications of telemetry systems. It is felt that the papers and tutorials which make up this year’s conference will provide you with some insight into these “Expanding Horizons.” The technical exhibits compliment the technical sessions. -
A Flexible 2.45 Ghz Rectenna Using Electrically Small Loop Antenna
A Flexible 2.45 GHz Rectenna Using Electrically Small Loop Antenna Khaled Aljaloud1,2, Kin-Fai Tong1 1Electronic and Electrical Engineering Department, University College London, London, UK, [email protected] 2Electrical Engineering Department, King Saud University, Riyadh, Saudi Arabia Abstract—We present the concept and design of a compact schlocky diode connected in series to one of the two feed flexible electromagnetic energy-harvesting system using electri- terminals of the antenna and to the coplanar transmission line, cally small loop antenna. In order to make the integration of the a capacitor to minimize the ripple level. The reported system system with other devices simpler, it is designed as an integrated system in such a way that the collector element and the rectifier in this letter is sufficiently capable of reusing low microwave circuit are mounted on the same side of the substrate. The energy for both flat and curved configurations. rectenna is designed and fabricated on flexible substrate, and its performance is verified through measurement for both flat and curved configurations. The DC output power and the efficiency II. DESIGN AND RESULT are investigated with respect to power density and frequency. It is observed through measurements that the proposed system The two main parts of rectenna system are largely designed can achieve 72% conversion efficiency for low input power level, individually and unified through the matching network. In this -11 dBm (corresponding power density 0.2 W=m2), while at the work, the proposed rectenna is built as an integral system, and same time occupying a smaller footprint area compared to the thus the rectifier circuit is matched to the collector to maximize existing work. -
The Classic Rain-Gutter Loop Antenna – Is It Any Good?
The Classic Rain-Gutter Loop Antenna – Is it any Good? A simple technical look at an HF horizontal loop of wire strung around your house at rain-gutter height, plus. some novel loop disguise techniques. By John Portune W6NBC Compromise disguise antennas are no strangers to hams, especially on HF. But which ones are worth the effort? We often just put them up and hope for the best. But when I moved to a CC&R restrictive mobile home park recently, I wanted better answers, particularly for the classic rain-gutter loop, Figure 1. I couldn’t put up more of an HF antenna without the neighbors noticing. But was it any good, or only little more than a dummy load? Figure 1: Classic rain-gutter-height loop, elevated on standoffs (stylized for emphasis) To find out, I challenged the rain-gutter loop with EZNEC antenna modeling software. This required best-case and worst-caswe models to encompass most house variables: (1) two loop heights, (2) two house types and (3) several bands. These would place most houses somewhere within these limits. Loop heights were: 10 ft. (rain-gutter height) and 25 ft. (a more conventional loop height). House types were: all wood (best case) and stucco/chicken wire (worst case). Bands were: 40M, 20M and 10M. Why didn’t I include 80M and 160M? Well, I did at first, but right up front, EZNEC revealed something very important about horizontal loops – Rule of Thumb 1. RULE OF THUMB 1 To be efficient, a closed loop must have a perimeter greater than one wavelength (1λ) on the lowest band in use. -
The Development of HF Broadcast Antennas
Development of HF Broadcast Antennas FEATURES FEATURES Development of HF Broadcast Antennas the 50% power loss, but made the Rhombic fre - Free Europe and Radio Liberty sites. quency-sensitive, consequently losing the wide- Rhombic antennas are no longer recommend - The Development of HF bandwidth feature. The available bandwidth ed for HF broadcasting as the main lobe is nar - depends on the length of the wire and, using dif - row in both horizontal and vertical planes which ferent lengths of transmission line, it is possible to can result in the required service area not being Broadcast Antennas access two or three different broadcast bands. reliably covered because of the variations in the A typical rhombic antenna design uses side ionosphere. There are also a large number of lengths of several wavelengths and is at a height side lobes of a size sufficient to cause interfer - Former BBC Senior Transmitter Engineer Dave Porter G4OYX continues the story of the of between 0.5-1.0 λ at the middle of the operat - ence to other broadcasters, and a significant pro - development of HF broadcast antennas from curtain arrays to Allis antennas ing frequency range. portion of the transmitter power is dissipated in the terminating resistance. THE CORNER QUADRANT ANTENNA Post War it was found that if the Rhombic Antenna was stripped down and, instead of the four elements, had just two end-fed half-wave dipoles placed at a right angle to each other (as shown in Fig. 1) the result was a simple cost- effective antenna which had properties similar to the re-entrant Rhombic but with a much smaller footprint. -
Antenna Articles Collection of Short Articles Relating to All Manners of Antennas
Antenna Tips page 1 of 31 Source : http://www.funet.fi/pub/dx/text/antennas/antinfo.txt Antenna Articles Collection of short articles relating to all manners of antennas. These articles are the hard work of Wayne Sarosi KB4YLY (995 Alabama Street, Titusville, FL 32796) SUBJECT: Circular Polarized Antenna There has been a request for a series on 'CP' antennas. The term 'CP' eluded me at first as I was not familar with the abriviated designator for circular polarization. At work, we just use the entire words. I'm going to begin this ten part series with the basics. After researching CP designs with a few engineers and fellow hams, I found that they knew very little about the subject. I also found I didn't know quite as much as I thought I did about circular polarization. So starting at the begining will help all out. First, let's discuss the circular polarized wave. There seems to be conflicting standards used by the world of physics and the IEEE. I found this to be true in four reference manuals including the ARRL Antenna Handbook. At least it's stated right up front but biased according to which text you read. We will follow the IEEE/ARRL standard in the following series for obvious reasons. There are two types of circular polarization; right and left. All of us agree up to this point. According to the ARRL Antenna Handbook, the following statement: 'Polarization Sense is a critical factor, especially in EME work or if the satellite uses a circular polarized antenna. -
MFJ 2004 Ham Buyers Guide
QSTCatP01.qxd 10/16/2003 10:03 AM Page 1 MFJ 2004 Ham Buyers Guide See inside for these New MFJ Products! 300W Automatic Tuner Tiny Travel Tuner DC Multi-Outlet Strips Ultra-fast, 2000 memories, antenna Fits in the palm of your hand! 150 has both 5-way binding posts switch, 4:1 balun, Cross-Needle and Watts, 80-10 Meters, Bypass Switch and Digital SWR/Wattmeter, 1.8-30 MHz Anderson PowerPole® connectors MFJ-902 $7995 $ 95 MFJ-1129 $ 95 109 MFJ-993 259 Four New models -- balun, Four new high current 150, 300, 600 Watt models. SWR/Wattmeter . DC multi-outlet strips . See Back Cover See Page 6 See Page 16 Balanced Line Dummy Load Manual Mic/Radio Switch Antenna Tuner SWR/Wattmeter Screwdriver Switch any 2 mics 1.5kW, to any 2 rigs Superb Antenna peak reading Covers 40-2 Meters balance, switchable 1.8-54 MHz, to external MFJ-1662 $ 95 $ 95 300 Watts antenna 129 MFJ-1263 99 $ 95 $ 95 MFJ-974H 189 MFJ-267 149 Four new models . Three new models . See Page 7 See Page 9 See Page 42 See Page 21 10 foot Antenna 160-6 Meter 1.5 kW 4:1 Glazed 4 Foot Telescopic Tripod Doublet current balun ceramic Ground Whip 40-inch Antenna /insulator insulator Rod MFJ-1954 between legs Copper bonded steel MFJ- $ 95 MFJ-1918 MFJ-919 MFJ-16C01 MFJ-1934 19 1777 $ 95 $ 95 $ 95 59 $ 95 3 lengths . 39 49 69c 4 See Page 42 See Page 42 See Page 43 See Page 43 See Page 43 See Page 7 Mobile Discone Atomic Atomic Wireless Speaker/Mic Antennas Antenna 24/12 Clock 24/12 Watch Weather for Yaesu VX-7R MFJ-1456, $14995 25-1300 Station MHz 40/20/15/10/6/2M MFJ- MFJ- MFJ-295R $ 95 $ 95 MFJ-1868 132RC 186RC MFJ-192 MFJ-1438, 99 $ 95 19 10/6/2M/440 MHz $5995 $1495 $2995 59 See Page 41, 39 See Page 40 See Page 29 See Page 30 See Page 30 See Page 35 Ameritron Ameritron Ameritron Hy-Gain Screwdriver Digital Screwdriver flat Mobile 80-10 M Vertical Antenna Antenna Controller SWR/Wattmeter The Classic is Back! 5 1.2 kW, Pittman Super bright high- Just 1 /8” thick, AV-18AVQII Commercial Gear Motor intensity LEDs flat mounts on $ 95 dashboard 229 SDA-100 SDC-100 MK-80, $79.95.