Other useful information would include your experience with similar products, infomation on a product that you would purchase instead of this one, and so on. Improved all band hf doublet was constructed and refined from the experience from my previous all band hf doublet for use with a zmatch antenna matching unit. My initial aim was actually for a 60 meter dipole antenna. Actually, its a design from zs6bkw aka g0gsf, similar to the g5rv, but it actually resonates on five bands, well 6, actually and doesnt rely on a tuner atu to make it work. I think that if you can deal with the open wire line routing issues, and use an efficient matching network tuner it may well be the very best multiband antenna.
The lengths given in the chart above are those of the full overall length total breadth of the bottom half of the linearloaded dipole. The gap in the top section can be a few inches wide at hf ex. I built this antenna and quickly tried it out in february of 20. Yes, i know its dipole length will give it 1 resonant frequency. In terms of magic lengths, ideally the antenna wires on a shack tuned doublet should be at least 38 wavelength on the lowest band of interest so that the antenna presents a reasonable matching impedance on that band and is reasonably efficient. Due to the variety of methods of analysis and design, and the different antenna structures available, the applications covered in this book are made to some of the most basic and practical. This was a serious contender because i figured it would probably load up just fine on some of the other bands with a pattern. An antenna system is the antenna and everything else between the antenna and the radio. This is the antenna for you guys who want to get on hf effectively, and havent too much space or cash to throw around. In the original planning of the book it was the intention of the editors to integrate all of. Introducing the allband doublet universitas padjadjaran. What is the best book regarding antenna systems excluding. The antenna length should be about a half wavelength at the lowest frequency of interest for best results. As an avid antenna experimenter, i have spent approximately 10 years in the field experimenting with this antenna design and its variants 14, 38, 12 wave.
This book covers various architectures from the simple dipole to the newer antennae that can be found in smart phones and gps systems. Your new doublet is a balanced antenna and will need a balanced antenna tuner. Analysis and design, 3ed by balanis and a great selection of related books, art and collectibles available now at. The norcal doublet antenna came about due to my desire for a simple antenna that could be erected very fast, only needed one center support, and did not take up much storage room. Perhaps too many new hams embarking on their first hf adventures think only of resonant dipoles fed with coaxial cable and plugged directly into the transceivers output connector. I just didnt know if the ladder line to coax junction was going to land in the right place. Its a classic doublet which is a half wavelength long on 80 meters fed in the center with ladder line. This book introduces the fundamental principles of antenna theory and explains how to apply them to the analysis, design, and measurements of antennas. This book introduces the fundamental principles of. Other names include the tuned doublet and dipole with tuned feeders. I think i need to find a slot for my the optimised doublet antenna talk at the club which ive given 3 times in the last 20 or so years. The success of the three previous editions of practical antenna handbook has been most gratifying.
Portable doublet the doublet has a long history and its longevity is perhaps down to two factors. In response, constantine balanis has updated his classic text. The antenna top is not cut to resonate at any particular frequency unlike the halfwave dipole, and any length may be chosen to suit an individual location. As an avid antenna experimenter, i have spent approximately 10 years in the field experimenting with this. This edition includes recent antenna innovations and applications. What the student and the instructor should keep in mind l. Open wire or balanced feeders are able to operate as part of the actual antenna. This book has been designed for both the undergraduate and postgraduate in electronic engineering, electrical communication engineering and electrical. No wonder then that lb cebik, w4rnl picked the doublet as one of his top five multiband backyard antennas cebik, 2009.
However it is my hope that newer, subsequent editions corrected a few of these glaring omissions like the slingshot, doublet, st louis, gotham and hamstick. The third edition of antenna theory is designed to meet. New material includes smart antennas and fractal antennas, along with the latest applications in wireless communications. The doublet can be remarkably efficient, despite the relatively high swr along its feed line. One end of it is opencircuited and the other end is fed with ac source. Describe your experience with the w7fg tuned doublet antenna and tell us why you give it the rating you did required. It was with surprise and delight that i noted that clerks in one radio. A more efficient version would be to feed a linearloaded dipole short ham antenna directly with 450 ohm ladder line or 300 ohm twinlead.
Louis doublet, that used small wire for the radiators and computer cable for the feedline. Doublet antenna article about doublet antenna by the free. I think that if you can deal with the open wire line routing issues, and use an efficient matching network tuner it may well be. In radio and telecommunications a dipole antenna or doublet is the simplest and most widely used class of antenna. The horizontal centerfed wire forms the antenna proper, which accounts for the radiation of transmitted energy and the reception of incoming energy. There is an explosion of available books and articles on the subject of antennae and antenna systems. The doublet has a long history and its longevity is perhaps down to two factors.
Note 1pages 710 and 11 of the arrl antenna book, qst. Grounded antenna theory 219 types of ground s 220 counterpoise 222 ground screen 223 section iii. The arrl antenna book uses the formula carr gives the figure as 0. Overall this 728 page book is good reference to ham antennas as well as antenna theory. Doublets, ladder line and automatic remote tuners the. Ictpituursi school on wireless networking for development the abdus salam international centre for theoretical physics ictp, trieste italy, 5 to 24 february 2007. Of course the first ham project here has been to get an hf antenna up. Antenna theory fullwave dipole if the length of the dipole, i. If your doublet was around 2 ft long, then the impedance at. The impedance at the centre of a doublet will vary enormously, depending on the frequency. You may have a pair of 70foot trees perfectly positioned to sup port a wire beam aimed at your favorite dx area. The discipline of antenna theory has experienced vast technological changes. Doublet multiband antenna that is not resonant on a particular band. Clerks in radio stores told me that this book was outselling other titles 2.
For a discussion of balance line tuners, check out owen, vk1ods webpages. The doublet is a nonresonant antenna that is intended to be used over very wide range of frequencies. But if a power line runs between the trees, forget it. I had also heard reports that this antenna is just a hair better than a dummy load on 7580m. Contents introduction to the fourth edition ix 1 introduction to radio broadcasting and communications 1 2 radiowave propagation 5 3 transmission lines 59 4 the smith chart 95 5 fundamentals of radio antennas 123 6 highfrequency dipole and other doublet antennas 141 7 vertically polarized hf antennas 173 8 multiband and tunablewire antennas 203 9 longwire. The dipole is any one of a class of antennas producing a radiation pattern approximating that of an elementary electric dipole with a radiating structure supporting a line current so energized that the current has only one node at each end. For years the handbook has shown the foot center fed doublet, using open wire line to be a recommended multiband antenna. They confirmed that the types of people who buy the book meet the profile above. Elliotts antenna theory and design is one of the most significant works in electromagnetic theory and applications. Contents introduction to the fourth edition ix 1 introduction to radio broadcasting and communications 1 2 radiowave propagation 5 3 transmission lines 59 4 the smith chart 95 5 fundamentals of radio antennas 123 6 highfrequency dipole and other doublet antennas 141 7 vertically polarized hf antennas 173 8 multiband and tunablewire antennas 203 9 longwire directional antennas 2.
A doublet antenna dipole, cut for 80 meters, will not work on 40 meters because 7 mhz is an even harmonic multiple of 3. Since the first edition in september 1939, radio amateurs and professional engineers have turned to the arrl antenna book as the source of current antenna theory and a wealth of practical howto construction projects. Dipole antenna length calculator dipoles antennas are easy to build and can be very effective when placed half a wavelenth or more above ground. In its broadranging, analytic treatment, replete with supporting experimental evidence, antenna theory and design conveys fundamental methods of analysis that can be used to predict the electromagnetic behavior of nearly everything that radiates. Ive put up the same multiband doublet i had at mont vernon. A further factor which influences antenna resonant length is the diameter of the wire used for that antenna.
These antennas are fed in the center, which point will be either a current node or voltage node depending on the design of the particular antenna. Im just a true amateur experimenter, antenna modeler and voracious reader of every book on antenna theory and design that i have been able to get my hands on, some 50 years old. Highly respected authors have reunited to update the well known 1981 edition which is still hailed as one of the best in its field. Dave gauding, nf0r, is a close friend of mine, and he had told me about a st. It provides a broadside pattern on every band it works. This is my 1 st contribution and i see the hot topic is the g5rv. Ladder line, and to a certain extent twinlead, are much less lossy transmission lines than coax. Like the previous editions, antenna theory, third edition meets the needs of electrical engineering and physics students at the senior undergraduate and beginning graduate levels, and those of practicing engineers as well. A halfwavelength dipole is the first antenna that a new ham operator or shortwave listener may put up. These are preliminary notes, intended only for distribution among the participants. A doublet antenna is a form of a dipole that is balanced with respect to ground. If you are wondering, the g5rv antenna is mentioned. The dimensions include the width between the balun connections. The zs6bkw multiband hf antenna iw5edi simone hamradio.
Nothing at all wrong with a 12 wave transmission line, in fact, 12 wave is the only length of transmission line that will repeat the antenna impedance at the transmitter end of the transmission line. It features a succinct treatment of the finite difference, time domain fdtd computational technique. Nonresonant dipole balun for ladder line page 2 qrz. The doublet antenna is a form of dipole operated with balanced feeder, typically open wire feeder and used with a tuning unit to provide multiband operation. The key to the doublet antenna is the form of feeder used. In its broadranging, analytic treatment, replete with supporting experimental evidence, antenna theory and design conveys fundamental methods of analysis that can be used to predict the electromagnetic behavior of. The g5rv or a doublet antenna of no particular significance. Do not install a balun between the ladder line and antenna. Doublet antenna article about doublet antenna by the. Perhaps too many new hams embarking on their first hf adventures think only of resonant dipoles fed with coaxial cable and plugged directly into.
To do this the g3rwf doublet antenna had to be modelled three times. This is my experiment with the 80 meter doublet antenna, using tv twinlead wire, which is 300 ohms. Enter the desired operating frequency in megahertz to get a good starting length for a dipole in both feet and meters. The antenna book mentions the folded dipole, but the information is scattered through chapter 6, with little theory even mentioned. The allband doublet is actually an antenna system and not just an antenna alone. Seeing all the useful comments and some confusion, i hope what follows helps. My shack is in the basement which presented a bit of a problem of how to get the ladder line in. Iw5edi 160 meter linear loaded tee vertical doublet antenna. The overall antenna is in the form of pcb, regarded to consist of a doublet antenna in the lower portion of figure 1a and an elliptic loaded monopole antenna with a skirted dipole in the upper half of figure 1a. This website is intended to be a source of knowledge for learning about and understanding antennas. The models were initially all referenced to 50 ohms, and later repeated with a 200 ohm reference. All the information you need to design your own complete antenna system. The folded dipole antenna consists of a basic dipole, but with an added conductor connecting the two ends together.
The range of frequency in which short dipole operates is around 3khz to 30mhz. Like lots of other people, you dont seem to appreciate basic antenna theory. With a 1064m2 14 acre town block with a depth of 60mtr 200 i intended to improve on my previous all band hf doublet with an antenna that would be. Matthew w0zzy had built one with homebrew ladder line and it seemed to work fine. With a 1064m2 14 acre town block with a depth of 60mtr 200 i intended to improve on my previous all band hf doublet with an antenna that would be suitable for all the hf amateur bands, including the so called warc bands and including the 160 metre band. Dec 28, 20 another antenna that is designed for 20m but works on 7580m is the g5rv. In theory, we could fashion a fourwire antenna for the 80, 40, 30, 20, 15 and 10meter bands. This book covers various architectures from the simple dipole to the newer antennae. If you have plenty of room for a real antenna farm, then a separate antenna and feed line for each band is the. In response, constantine balanis has updated his classic text, antenna theory, offering the most recent look at all the necessary topics. What these numbers have in common is the belief that the feedpoint is the 300ohm point along the antenna element. The doublet antenna is essentially a balanced system and each half of the top plus each wire in the feed line must be equal in length. It is a benchmark text for mastering the latest theory in the subject, and for better understanding the technological applications. As i work mostly qrp, i need to minimize rf losses as much as possible.