This site documents my activities in the hobby of Amateur Radio. On the HamRadioHelpGroup. He has had incredible results with this kind of antenna and has written a paper on it. Antenna Basics and Theory - From Sub-TV; Antenna Basics and Theory - From Thierry Lombry; Antenna Basic Radiation Theory- From The ARRL; Antenna Basics and Theory - Excellent - From VK2DQ; Antennas - How They Work - Very Good Article; Antenna Construction Tips And Practices - From KQ6RH; Antenna Dimension Calculators - From The Antenna Elmer. Yagi antennas for years and considered them to be good DX antennas, so I chose that design as the performance standard for comparison. Enjoy this collection of some of the very best articles from QST, QEX, NCJ and other ARRL publications. The author can be contacted at [email protected] This antenna covers 17 to 30 MHz and has performed well. Known as the Magic Band, the six meter band can be mysterious, unpredictable, and downright fun. Texas Potato Masher antenna by Gerald Brown, K5OE shown in Figure 17. We will submit one big order to Ed as a club. It's the ubiquitous circular waveguide "cantenna": I obtained my can by going to my local 99 Cents Only store and buying a can of Heinz beans, which happened to be desired 3. What is NOT shown in the above chart is how seriously the loss increases as we use fewer than 16 radials. The ARRL Antenna book Discone Antenna Calculator. My program uses the equations in the ARRL Antenna Book, 18th edition, page 26-4. The formula for calculating the approximate length of a quarter-wave vertical antenna is:. PolarPlot Antenna software that lets you measure the polar diagram of a rotatable beam antenna. The material in this article is derived from The ARRL Antenna Book, 1957, 1974, and 1999 editions; Army Field Manual 24-18 and others, several QST articles, and various web articles written by other NVIS experimenters and HF antenna and propagation experts such as. A few days ago, I had a QSO with Rich, K8NDS, of Prescott, AZ on 40M. if that so for low frequency signal. let me jump the theory and experiment that later after i have a transmitter ready. The original Hentenna as a special kind of a single loop was described first in the 1970ies by Japanese Hams, an English article by JF6DEA/KE1EO about the Antenna ("The Hentenna - The Japanese 'Miracle' Wire") was in the QST 1982 and in the ARRL-Antenna- Compendium, Vol. Antenna gain is measured in either dBi or dBd. Antenna Design Calculator v. Horisontal Loop Antenna for Shortwave Listening and Amateur Radio Use. I have received a lot of e-mails asking for details about this antenna, and especially the two-capacitor matching network at the base of my inverted-L (which was --much to our surprise-- featured in a ARRL Contest Update newsletter). This Cobweb Antenna is using a double 1:4 balun that can handle a little more then 2 KWatt, also the wire's can handle the load of high powered stations. Doublet - Multi-band antenna that is not resonant on a particular band. The ARRL Antenna Book. of The ARRL Antenna Book and was interested to see a design for a 2-ele-ment quad. 4 metres) of ice hanging from it in May!. The HX1 is a low-power radio transmitter set to a fixed frequency of 144. This program uses the formulas given in FCC OET Bulletin No. Cebik, W4RNL (SK) in the 21 st edition of The ARRL Antenna Handbook. An antenna "tuner" is used to reduce the SWR on the antenna. Please report FAILED WEB LINKS here. pedance at the overall antenna feed point A Simple Fixed Antenna for VHF/UHF Satellite Work Explore the low-Earth orbiting amateur satellites with this effective antenna system. References. Fortify your existing antenna or build your own with high-quality brackets, clamps, tubing and supports from DX Engineering. So in this case, we want to build an antenna for 6 meters, 50. Stroobandt, ON4AA, in the year 2006. Bhartia: From description:"Topics covered include transmission lines and lumped elements, resonators, impedance matching networks, hybrids and couplers, filters, active and passive solid state devices, oscillators, amplifiers, detectors and mixers, microwave control circuits, frequency multipliers and dividers, computer-aided design. ) Buckmaster 8-Band OCF Dipole Antennas are 270 feet (82 meters) long and work on 160 (tuner may be required), 80, 40, 20, 17, 12, 10, & 6 meters. Is this a common problem? What is the best plan of attack?. Random Wires 2. Dipole Antenna Length Calculator. There is a phasing coil between the cylinder. The antenna, combined with a ground radial or counterpoise system and an antenna "tuner", will cover these three bands in style. Antenna and Tower Safety. If you would like to send a message to the WV Section Emergency Coordinator, Mike, W8SI, please send an email to his callsign at arrl. The challenge part is that I wanted to use stuff I had lying around, and I wanted to build. You need: Target Frequency: The computed solution is a function of frequency. To be published on a bimonthly basis, On the Air will offer new and beginner-to-intermediate-level radio amateurs a fresh approach to exploring radio communication. The antenna described here is a direct-connect dual-rectangle beam for use on 70 cm between 440 and 450 MHz. antennaX - Online Magazine W4RNL - Super Site Crossed-Field Transmission Antenna - An interesting design How To Become An Antenna Guru do antenna calculations with a wave of the hand HF Antenna Estimator - Online antenna calculator. All About Circuits - A collection of very useful data and calculators for circuit design. Here is a brief description and some pictures of our inverted-L antenna and tuner. The ARRL "Antenna Book" (ed 1998, ch. The Yahoo Magnetic Loop Antenna group is a discussion forum for design and construction of magnetic loop antennas. Antenna Orders: Ed’s Antennas. rhombic or some other configuration. The Moxon antenna hold promise as a Jupiter antenna. used the calculator to design several other antennas for 70, 33 and 23 cm. The HamWaves. Antenna Theory 101 -- Excellent Tutorial From KD4SAI Antennas from QRZ Shareware -- over 40 antenna files ARRL Antenna Projects Loaded With Many Antenna Projects AA3PX Antenna Page -- Conversations with Dr. ARRL Product Review of the M2 6-Meter HO Loop Antennas. Resonates at 50. For more on this publication history of this formula, see this article by N0AX. com) to pick out what you want. It's very suitable to VHF antenna modelling and even if it is very old it is still very popular. The most common CATV cable is 1/2-inch OD 75-Ω Hardline. If you are looking for maximum signal using a Narrow Mode such as CW or SSB, it is pointless using a wideband antenna (ergo balun) in which case a narrow bandwidth balun is best. Includes spaces for callsign, date, location and page number at the top of each page. 2D: RJELOOP1 calculator for performance of single-turn magloop antennas of various regular shapes and MAGLOOP4 calculator for performance versus height and type of ground, by Reg Edwards (G4FGQ, SK). His 1950 book, Antennas2, is the classic source of information. He has had incredible results with this kind of antenna and has written a paper on it. New Year’s Day. To run this locally, you can download the file tuner. It needs no tuner on 40m, 20m and 10m. When employed as a transmitting antenna, it is often less efficient than an antenna designed for a more limited frequency range. Resonates at 50. If you would like to calculate just wattage and antenna gain without the transmission line and its effects, simply insert a low frequency into the Frequency text box (0. If you are not eligible but would like to read the user's manual, download the Zip file and. net [this is the web version of the article that appeared in the November 2006 issue of CQ] Operating on 160 meters has always been a challenge. These rules can be found in the FCC's ET Docket No. In contrast with the omnipresent turnstile antenna (two crossed dipoles with a reflector) the circularity is almost perfect in any direction. It can be deployed quickly and is ideal for use in places where HOA restrictions make full size wire antennas impossible, or where there is not enough room to erect a conventional antenna. This LPDA calculator is mainly based on the design procedure as described by L. (Meaning one side of antenna to one conductor of feedline and the other side of the antenna to the other conductor of the feedline. Directional Indoor UHF/VHF HDTVi Antenna - YouTube If you think youre going to get true 1080i local HDTV broadcasts from satellite or cable think again. 3 A useful microwave antenna calculator The antenna calculator is a very simple and easy piece of software. html into any convenient directory and point your browser at the tuner. ) Bicycle Mobile Hams of America site & Yahoo! Club GOBAHams. 1 MININEC and NEC-2 would have been equally satisfactory. Get Started. Monoband Beams for 12 and 17 Meters I designed a pair of driver-director Yagis for 12 and 17 meters using antenna-modeling software, in this case, NEC-4. My procedure involved two steps: creating a basic design with a uniform-diameter. Paul Danzer, N1II, has been a licensed ham for over 50 years. Use a tunable L-Network or any antenna tuner capable of matching high impedance loads, and it's a good multiband system. The MVARA participates in the American Radio Relay League (ARRL) sponsored Field Day. Log Periodic Antenna Calculator Loops-- From The ARRL Loop Antennas-- Plans for each Amateur Band Loop Antenna Forum-- Yahoo -- Needs subscribing but lots of info here Low Band Antennas-- From K3KY Mac Antenna Master Software Magnetic Loops for HF-- From W2BRI HF Magnetic Loop Antennas-- By Glenn C Sperry, KI6GD Magnetic Loops-- By Wolfgang DJ3TZ. For an good efficacity and directivity on radio spectrum it's necessary to use an YAGI antenna. com in 2 categories. At multiples of half wavelengths of the transmit frequency the impedance is so high that tuners in most rigs often can't match it. There is the ARRL Antenna Book CD with “Gamma,” the ON4UN’s ARRL Low-Band DXing book CD with “ON4UN's Low-Band DXing. This program will allow you to recalculate designs for thin wire elements. 8 metres) doublet antenna with over 8 feet (2. The log periodic antenna works the way one intuitively would expect. Many hams’ first choice of antenna is a half-wave dipole. This calculator is designed to give the vertical length (height) of a particular antenna, for the frequency and wavelength chosen. Resonates at 50. http://www. , which is loaded with practical information. RG-58 TRAP, 75 ohm VSWR, 40 METERS. The greatest advantages of H Double-Bay antennas are that they can be constructed and hung for very little in terms of both time and money compared with mounting beams for various directions either on side-arms or on additional towers. A List of ANTENNA Projects; ANTENNAS - N4UJW; ANTENNAS - DX Zone; Dipole and Inverted V Antenna Calculator; Vertical Antenna Calculator; J-Pole Antenna Calculator; HAM RADIO GATEWAYS. This article describes a specific procedure to adjust a shunt matching coil to assure that the input SWR will remain relatively low (≤ 1. ARRL Antenna Book, 18th Edition. This calculator enables you to test the design of an octagonal loop antenna and to answer "what if" questions until you arrive at a design that meets your needs. New Year’s Day. From the ARRL Web Page: "This web page was created and is maintained by Steve Ickes, WB3HUZ. June 25 and 26 local Ellsworth Amateur Wireless Association (EAWA) ham radio operators will be participating in the annual ARRL Field Day event which is being held at the SERC (Schoodic Education and Research Center ) located at the decommissioned Navy Base on Schoodic Point in Winter Harbor. This sketch shows a semi-exploded view of the antenna. The Zip file can be downloaded from the ARRL website. For angles greater then 90 degrees the legs will have less of an increase in length. For details, read the ARRL Antenna Book. It is inversely proportional to the frequency which means the wave with higher frequency will have shorter wavelength. If you want a shipping quote, email [email protected] Before you start constructing your own LPDA using the LPDA calculator below, please read chapter 10 of the 20th Edition of the ARRL Antenna Book (Other editions of the ARRL Antenna Book work as well, but may. Being that I was building a 10 thru 80 antenna ( if you remember it was a 40) I had to change the length of wire also. PolarPlot Antenna software that lets you measure the polar diagram of a rotatable beam antenna. Note: Be sure you are using the latest version of the TrustedQSL software! Download TrustedQSL. Dipole and inverted V calculator from the Carolina DX association EH Antenna calculator from IW5EDI Ground Plane antenna (Quarter wave) From Computer Support Group J-Pole calculator From K4ABT. The ARRL Antenna Book: The Ultimate Reference for Amateur Radio Antennas, Transmission Lines And Propagation (Arrl Antenna Book) [American Radio Relay League, R. org about the page or its contents. Today, with more than 158,000 members, ARRL is the largest organization of radio amateurs in the United States. Geometriy is not that critical. Within this physical description there are two distinct antenna types. Dipoles antennas are easy to build and can be very effective when placed half a wavelenth or more above ground. (This will be organized. References. From my initial research in various ARRL publications, I discovered that a half-wavelength of wire for a chosen frequency wound in a helix on an insulating form such as a wooden pole, a fiberglass pole, or even pvc pipe could duplicate the performance of a standard 1/4 wavelength vertical antenna. Hey everyone! Ed’s given us another chance to order his antennas. You'll find it interesting and educational, and you'll get many useful tips about antennas and modeling from the extensive on-line manual. workshop to construct the antenna. It is the same antenna that appears on the front cover of the ARRL VHF/UHF Antenna Classics Handbook. antennaX - Online Magazine W4RNL - Super Site Crossed-Field Transmission Antenna - An interesting design How To Become An Antenna Guru do antenna calculations with a wave of the hand HF Antenna Estimator - Online antenna calculator. Home of the AM Press/Exchange, The AM Forum (the largest BBS of it's kind),and The AM Classifieds, Photos, Audio, and technical information. A site dedicated for the AM Radio Amateur and vintage radio. Click here to Skip the intro and go to some actual construction. For the dipole-based turnstile antenna, we’ll either have. I constructed this antenna with the most streamlined and easiest layout for my particular QTH. Using modeling soft-ware, I tested several log periodic anten-nas of six to eight elements with boom lengths of 16 to 20 feet. We do not normally stock it. frequency for doublet and loop antennas. 6 of the 22 nd Edition of the ARRL Antenna Book. It is by no means a replacement for antenna design software such as EZNEC, but should give a clue how the antenna will perform. NOT THE ANTENNA! *W7EL is the author of EZNEC antenna modeling software. The most recent edition is the 21st. The beam antennas covered in this book will provide the reader with a historical perspective, new and ambitious ideas, and computer-optimized designs for all-around best performance. An article from the June, 2001 QST. Larsen 144-148/440-450 MHz Dual Band 37. net ARRL Antenna Book CD. Compre o livro Practical Antenna Handbook na Amazon. He has had incredible results with this kind of antenna and has written a paper on it. It is important to note that …. He was S9+10dB here in Salt Lake City. Quad calculator Cubical quad antenna calculator in java script. The ARRL Antenna Book describes two common configurations of the J-Pole antenna: an open-stub version and a shorted-stub version. Antenna Design Calculator v. Diameter and length of inductor are entered in millimetres along with the number of turns. 1l) loaded radials can be efficient - with careful design". This is the main reason NOT to use this kind of balun as a tuner balun. This calculator is designed to give the critical information of a particular beam antenna, in this case a three element Yagi, for the frequency chosen. Diameter and length of inductor are entered in millimetres along with the number of turns. For long runs, the RG-8 or better cable is required. Full Logbook Sheet (Portrait A4) Portrait logbook with 34 entries. ARRL extends its thanks to the volunteers that help make ARRL's web pages a useful resource for all. Engineers view antennas as filters in both space and frequency, since antennas are only looking in certain angular regions over certain bandwidths. How to become a Radio Amateur (ARRL) New licensing structure (ARRL) Band allocations by operating class (ARRL) VE Exams in your area (ARRL) VE Exams in your area (W5YI) Amateur Radio Newsline (TAPR) FCC Amateur Radio Service (FCC) Radio Modifications (QRZ) Renew License/Update (QRZ) Design Your Own Antenna (W4SAT) Open Amateur Repeaters (ARTSCI. It was first described in the US in a Feb 1982 QST article by Koji Sugihara, JJ1UMS and Shirow Kinashita, JF6DEA/KE1EO wrote about it in the ARRL Antenna Compendium Vol 5. Info on what’s going on with the Sun ! Space Weather. The source tarball is supplied. if that so for low frequency signal. This page covers 3 element Yagi Antenna calculator. Pretty sure he's not "wanting to know" anything he's just offering up a very detailed calculator program he took the time to write and distribute, that allows advanced builders to design and build their own true ladder line feedline system. The quadrifilar helicoidal antenna - quite a mouthful - is easy to construct (even though it does look complicated), and the results are excellent. Antenna Software FOR QUICK FIND USE YOUR BROWSER FIND COMMAND OR DO A Ctrl F, type in the sought after item. All the antennas in the Array are putting in the same amount of effort to achieve a stronger signal than the single individual. 8 ohms at 1. The feed point is usually placed at the centre of the dipole, for although this is not absolutely necessary, it can help prevent. 40-10 Meter Portable dipole Phil Salas – AD5X ([email protected] Antenna Project Design exercise: an 80-foot 75-m dipole antenna by Dick Smith, W4ZQV. the dimensions of the helix are so noncritical that the helical beam antenna is one of the simplest types of antenna it is possible to make circumference turn spacing (phase angle) reflector size conductor diameter helix support (boom) Kraus Gain (db)=10log3. The calculator was successfully tested against the examples listed in this ref-erence. An article from the June, 2001 QST. The start at 7125-7300 vice 7175-7300 per ARRL. Yagi Optimizer is an old DOS program made more than 20 years ago byÂ K6STI made to analyze and design antennas. I'm not one to spend a lot of money on a commercial antenna that I can build from parts laying around or found at the local hardware store. ARRL-WCF Tech. Cebik, W4RNL (SK) in the 21 st edition of The ARRL Antenna Handbook. Maps for Amateur Radio Maps for Ham Radio Operators. This helpful antenna trimming tool will come in handy if you need to add or cut wire from your dipole or vertical antenna elements during portable, emergency, or Field Day operations. Requires antenna tuner. The Wire Size can range from 16 AWG to 12 AWG. There is the ARRL Antenna Book CD with “Gamma,” the ON4UN’s ARRL Low-Band DXing book CD with “ON4UN's Low-Band DXing. It needs no tuner on 40m, 20m and 10m. The best balun to use is the one that does the job with the least loss, of course. The source tarball is supplied. always appreciate your input @k8md. 25λ high, then a lot of the transmitted energy goes straight up. Portability is another. Yagi Calculator is a program to assist with the design of long yagi antennas. Depending on the relative phasing of two or more radiators, the field at a given distance will either reinforce or cancel. Search this site. The section for each edition contains links to supplemental files and software, non-ARRL documents, and errata and corrections. Order 7-Band 5,000 Watt OCF Dipole Antenna: $707 Special Price: $538 (5,000 watt models are special order only and are made on-demand, so will always take a couple weeks to ship. It is intended for a wide audience, not only for hams, but also, for those that might want get into the hobby. Smith Chart Software. The ARRL Antenna Compendium, Volume 1 (Volume 1) by Gerald Hall and a great selection of related books, art and collectibles available now at AbeBooks. 3 to 1 on both bands. If I receive a QSL card, I will return a QSL card - eventually. If you would like to contact the WV Section Manager, Dan, K8WV, please send an email to his callsign at arrl. This project answers that. This does NOT take into consideration the type or size of horizontal reflectors, of even if there is a need for them. The normal quarter wave ground plane antenna consists of a vertical radiator which is insulated and centered between 4 horizontal surrounding radials which extend out from the base of the antenna. Magnetic Loop Calculator v. (Source ARRL antenna book) THE HEIGHT VERSUS TAKE-OFF ANGLE. Quad calculator Cubical quad antenna calculator in java script. It is important to note that …. USEFUL LINKS. This calculator was adapted from the Coil-Shortened Dipole Antenna Calculator. A whip antenna is an antenna consisting of a straight flexible wire or rod. (end fire in 2 directions plus broadside, etc). com or call 800-221-7735. It's easy to just put a variable ca-pacitor across the input to the antenna and find the value that gives the best match. Indoor Antenna Construction Tips. EZNEC - A very nice antenna modeling program by W7EL. From my initial research in various ARRL publications, I discovered that a half-wavelength of wire for a chosen frequency wound in a helix on an insulating form such as a wooden pole, a fiberglass pole, or even pvc pipe could duplicate the performance of a standard 1/4 wavelength vertical antenna. This model is for meteorological satellites, but a calculator is provided to adapt measure to other frequencies. Find helpful customer reviews and review ratings for Arrl Antenna Book at Amazon. Reviewed by Bob Allison, WB1GCMAssistant Laboratory [email protected] , 1982 Published in ARRL Handbook from 1985 to 1987 or later Also K. Please post a comment if you know other great software or links with information about antenna calculator and design programs. The ARRL Lab verified that the general purpose formula gives conservative estimates for a number of dipole, ground-plane, and Yagi antennas. The antenna tunes from 10 through 20 meters and is rated for 100 W input. You can also select from the links below to some of the more popular antenna pages. What type of feedline coax should I use for my antenna. The basic premise of the calculator is that you have transmitters, antennas and connections. I was surprised to discover that the dimensions Figure 1 — Cubical quads, like this one assembled by the author, can last a long time by using the proper construction techniques. It offers true ½ wavelength performance at both VHF and UHF with no ground radials. which would seem to indicate that not all the online calculators use the simplified ARRL math mentioned in. 40 is good off the ends; 80 is good broadsides and vertical at the same time (more so than on 160). Description of the construction of a quadrifilar helicoidal antenna. (WS6X) will save you a lot of time as you configure and trim your HF antenna ideas. 93 KB How ET Really Called Home. The dimension limits are enforced to ensure axial-mode radiation. I planned on using the ARRL 10m weekend as family time, so for the few minutes I turned the radio on, I found my decision to be justified. From the ARRL Web Page: "This web page was created and is maintained by Steve Ickes, WB3HUZ. I was trying to increase the overall performance of the J-pole, in this design. 27-28) confirms also that for low bands between 1. 27 MB Horizontally Polarized Omni-Directional Antenna. Hey everyone! Ed’s given us another chance to order his antennas. com Quality antenna systems by Mosley Electronics. Dean Straw] on Amazon. , 1974, and 14 ed. Loop Antenna Fields. Electromagne2c' Wave'Polariza2on' • Electric'and'magne2c'waves'are'at' right'angles'to'each'other' • Magne2c'wave'dissipates'within'a' few'wavelengths'of'antenna. Portability is another. I’d highly recommend that you add it to your list of favorite podcasts. A Hawaii-based Amateur Radio Antenna Blog focusing on the theory, design, and use of homemade antennas. The ARRL Antenna Handbook (16th ed. And two, the ARRL 10 meter contest is this weekend! I seem to be making a habit of building a new antenna before (or during!) every contest I try. Home Antenna Transmission Line Calculator by talks about amateur radio contesting, ARRL Field Day, and the CQ World Wide DX Phone Contest. For a more in-depth examination of matching networks, consult the ARRL Antenna Book. Sloper antenna for both 40 and 15m bands cut into tower guy wire. USEFUL LINKS. does wavelength decides height of antenna. Liquid-based. I used this software programs for several goals: projects of circuits, filters calculator, differents design antennas etc. Even More Wire Antenna Classics (Vol 3) Even More Antennas to Build - Even More Ideas to Experiment With For those familiar with the ARRL books Wire Antenna Classics and More Wire Antenna Classics this book has been long awaited. The ARRL Antenna Book 21 (Straw 2007) gives equations and advice for design of small transmitting loops. Yesterday, I worked a guy who said he was running 500W. WCF Technical help and Tech Net Info. The ARRL Antenna Book. This map to the "Treasure Island" of incredible antenna performance was lifted from the 14th edition of the ARRL Antenna Book, page 7-1. Antenna modeling suggests that the impedance is closer to 1800 ohms depending on the "counterpoise" length used. The antenna is designed to be fed with 50 or 75 Ohm Coax Cable of most any length with a Balun. The code was developed by Bill Wortman, N6MW and generously donated to the ARRL and the readers of the Antenna Book, ARRL Handbook, and Low-Band DXing by ON4UN. AC6V AmRad and DX Ref. Following limitations apply: Total dimension (H+L) less than. Plugging in the average value for K obtained above in the wavelength equation gives L = 11244 / f in inches for 1/2 inch copper pipe J-Pole antennas. Recently I've been fielding service problems from people using 88-foot long dipoles. The turnstile and eggbeater antennas more closely approximated an omnidirectional pattern with 0. An excellent receive antenna for the lower bands is the Beverage antenna. Realizing many hams are mathematically challenged, only simple mathematics procedures are used. 2% for the longest side after determining the half wave length at the lowest operating frequency…. used the calculator to design several other antennas for 70, 33 and 23 cm. Many of these techniques depend on the frequency of use and the antenna type. There are two gamma calculators that have some degree of distribution plus another of interest that have been found. used the calculator to design several other antennas for 70, 33 and 23 cm. Bahl and P. 88 ft and 44 ft are popular lengths. This site documents my activities in the hobby of Amateur Radio. (• Windom(for(10(- 40(meters(shown. It is with profound sadness and broken hearts that we here at In Compliance Magazine mourn the untimely passing of our dear colleague, mentor and friend, Glen Dash, who died on September 19th at age 66. As mentioned radio horizon is the function of antenna height. Most transceivers and antennas designed for ham use are based on 50 ohm impedance. The antenna will need to be temporarily fed at its center with the same sheath current choke. Matching to the feed-line is achieved by sliding the connection of the feedline back and forth along the stub until an impedance match is obtained. To evaluate a VHF/UHF antenna on a car, we only need to look at the horizontal (azi-Your 2 Meter Mobile Antenna – What’s the Best Mounting Location? Where you mount that antenna makes a difference. The ARRL Antenna book has a section on Shortened dipoles with a chart for determining the approximate inductance values for off center loaded dipoles. Note that antennas are very rarely constructed according to the calculated theoretical dimensions and are always tuned to the lowest standing wave ratio (SWR) and. This does NOT take into consideration the type or size of horizontal reflectors, of even if there is a need for them. It is intended for far-field calculations, at distances at least several wavelengths from the antenna. Unlike the book, this calculator employs the velocity of light. There's now no doubt in my mind that a random wire can be an effective antenna. The best balun to use is the one that does the job with the least loss, of course. Yagicad is a fully integrated analysis and design package primarily intended for VHF yagi aerials. The position of placement of the loading coil will play a part in the overall efficiency. 3) What can you stick between a 3. W5OJM (Brooks Shera) GPS Controlled Frequency Standard. I regularly bust pileups I never thought I had any business being able to bust, including Mozambique during the most recent ARRL DX SSB contest, when he was only S2-3 to me. Notebook Antenna Page - Antenna links, manufacturers, mailing lists, E-Zines. The 5 bander CobWeb Antenna is a High Quality designed antenna with products from Europe. Â These are a few of the modifications I came up with. See our other Electronics Calculators. The ARRL Lab verified that the general purpose formula gives conservative estimates for a number of dipole, ground-plane, and Yagi antennas. Indoor VHF antennas vary based on band and mode. As I studied the ARRL Antenna Handbook I learned about the various types of antennas. pdf), Text File (. Some can be 'home brewed' (others have embedded proprietary code). This calculator was adapted from the Coil-Shortened Dipole Antenna Calculator. 64 meters) long. This review of NI4L's 7 band OCF dipole was prompted by my needing a quick deploy multiband antenna for both field day, and for RVing. We had 1 of this item in stock at the time of the last update. Beside search engines, forums and radioclubs that can answer to your questions, to get some awards for example you need to know what DXCC entities, IOTA, Antarctic bases or lighthouses are requested. This is a great question, as the coax you select can make a dramatic difference on the performance and range of your antenna system. The basic geometry of the antenna is shown in the following figure: An interesting feature of this antenna is that both dual-rectangular elements are electrically connected together, so strictly speaking, the antenna is a single. Some can be 'home brewed' (others have embedded proprietary code). It is the energy storage or reactive induction field response within λ/10 distance from the antenna that gives small "magnetic loop" and "electric dipole" antennas their names. Here is another DIY Yagi antenna design for 1200MHz and also suitable for 2400MHz: Construction details from calculation: VK5DJ´s YAGI CALCULATOR Yagi design frequency =1200,00 MHz Wavelength =250 mm Parasitic elements fastened to a non-metallic or separated from boom Folded dipole fully insulated from boom Director/reflector diam =4 mm Radiator diam =3,5 mm REFLECTOR 121 mm long at boom. June 1991) helped me understand what essential considerations I had to take into account. Geometriy is not that critical. The ARRL Antenna Handbook; A Tin Can Design with good theory information. Yagis, Quads, Loops, and other Beam Antennas. One of the simplest antennas to have, and to model, is the quarter-wave vertical. Very close to a small loop antenna (but not necessarily near the open ends of the small loop where the tuning capacitor is) the magnetic field. The current ARRL Antenna Book comes with a PC calculator application Finally, the ON4UN book (4th ed) contains Table 13-10 with yagi gamma match examples. In the graph below I have plotted what MININEC predicts for the impedance of an end fed half wave antenna versus the "counterpoise" length. Just Ask ! ARRL. com in 2 categories.