Zepp antenna theory It was written primarily for the newcomer and the non-technical old-timer. Jul 10, 2021 · Vertical extended double zepp antenna for 2 meters and moreA Hawaii-based Amateur Radio Antenna Blog focusing on the theory, design, and use of homemade antennas. Along with the EDZ, the bi-square and W8JK designs are reviewed and the alignment of currents will be related Zepp antennas derive their name from the antennas used on the Zeppelin Airships. The antenna to which I refer is the Zepp and the gigantic hydrogen-filled balloon is, of course, a Zeppelin. Nevertheless, the EFHW antenna had in the past, been rather sparingly used by amateur radio operators due to various reasons. At optimum heights, a common 1/2 wave dipole actually has about 8. 5 dB gain over an isotropic radiator! Always remember that when you see antenna models over earth that tell you an antenna's gain in dBi. The tuner must convert the 50-ohm impedance (unbalanced) of the station trans-ceiver to the often high impedances (balanced) pre-sented by the antenna-plus-feedline system. A Double Zepp is a center-fed 1/2 wavelength antenna. We present the basic theory and rigorously validated calculators to analyze and design numerous antenna types and related components. After WWII coaxial lines became readily and cheaply available. The concept of creating and aligning antenna currents is introduced. The antenna consists of symmetrical horizontal radiating elements being driven via an open wire ladder line or a With a modest lot size and height limitations there have been several antennas of which have been tried at this home QTH. Trailed behind the airship, it consisted of a single element, one half wavelength long radiator with a quarter wave parallel feedline tuning stub. The antenna may be in-line or in a right angle L-shape or hanging free. The matching stubcreates the With high SWR voltage and current form nodes and loops along the line Old-time Zepp antenna was voltage fed Stubs An open or shorted quarter-wave stub inverts the impedance at the input end. If you have sufficient space, the Zepp will perform very well. The ef fectiveness of an antenna depends upon numerous electrical and mechanical factors of design, all of which are discussed under The Extended Double Zepp (EDZ) has been a lonely antenna for most of its life, since Hugo Romander, W2NB, introduced its potential to the amateur community in 1938. I am always learning so you may see this page change from time to time as I learn more and correct errors. A 1/2 wavelength wire antenna, fed at one end with parallel transmission line is also known as the end-fed Zepp. This double extended version provides 3 db gain over a dipole on the band it is designed for and each side or leg is about 5/8 wavelength long The first, which was used on the Zepp antenna and on the J-pole antenna, is to use a quarter wavelength matching length of transmission line, usually ladder line. It was originally used on Zeppelin airships in World War 1 as a trailing wire lowered from the airship while in flight. So that the feeders can be matched to the transmitter, a transmatch is used at the "shack" end of the line. In theory antennas, like dipoles and Yagi’s, are consider balanced antennas, unless they are up high and in the clear there will be some level of unbalance in the antenna. We strive to ensure the accuracy and updating of the information and calculations provided, but we make no warranties or An example of an antenna that does not use a counterpoise, is end fed, and half wave long, is the end fed Zepp. If a model over earth shows a "gain" of about 8. 25 wavelength long wire, fed at the center with an open wire transmission line and a tuner at the transmitter end. The Single Wire End Fed Antenna is probably the simplest antenna to use. Figure 1 shows the general outlines of a Zepp cut for the 80-meter band. 1 By contrast, everyone knows about the family of antennas related to the Antenna unbalance is caused by all those things that surround an antenna, buildings, trees, powerlines, fences, cars, and so on. Sometimes the ground is used in conjunction with the antenna con ductors, as will be defined later. Reviewing old antenna books and amateur magazines, longwires and Zepps were popular antennas. The J-pole antenna, more properly known as the J antenna, [1] is a vertical omnidirectional transmitting antenna used in the shortwave frequency bands. It covers 7 bands, 10-12-15-17-20-40-80m. Moved PermanentlyThe document has moved here. In Jun 19, 2025 · Theoryedit The design criteria begins by stating that the j-pole is an end-fed vertical half-wavelength antenna (also known as an end fed zepp), that is matched to the transmitter output impedance by a series tuned section of transmission line. Feb 18, 2024 · Double extended Zepp antenna can be considered as a 1. But when you start looking around, you find that no one can agree on what length to use. Zepp antenna. The CHA ZEPP Antenna has been specially designed for apartments, condominiums, homeowners associations, deed restrictions and CCRs (Covenants, Conditions & Restrictions), ARES, RACES, MARS, EMCOMM, NVIS, First Responders, Emergency Preparedness, Shortwave Listening (SWL), and The End Fed Half Wave Antenna HOME E-mail On this page I will try and describe what I know about End Fed Half Wave Length Antennas. Mar 31, 2018 · Zepp (or Zeppelin) Antennas in their myriad forms can provide a wealth of experimental data for radio amateurs seeking to improve the performance of their antennas. Best suggestion is to make the antenna for the lowest operating frequency so that you can operate the entire band you desire . How can a transmission line act as an impedance transformer? In theory, we could fashion a four-wire antenna for the 80, 40, 30, 20, 15 and 10-meter bands. Popularity of end-fed antennas faded as coaxial-fed antennas became mainstream. The antenna was originally used on zeppelins, with the dipole trailing from the feeder, which hung from the airship cabin. Witt says: “The antenna system described here is simpler than any of its prede-cessors and has the following features: A 2:1 SWR or better is achieved over all or most of the 80-meter band. I don't expect anyone to take this information as gospel. It consists of a half wave antenna at the low est frequency of operation, with parallel copper tubing quarter wave feeders con nected in the center End-fed halfwave antennas were once very popular. Nov 6, 2025 · The Antenna Calculator aims at delivering a comprehensive and practical tool to Antenna Engineering students and practitioners. According to Peter, this design is omidirectional and can hit distant repeaters with ease. It has been recommended that coaxial cables are not the type of feeder to be used for a double extended Zepp antenna. End fed longwire or random wire antenna Groundplane Verticals (they are generally end-fed 1/4 wave radiators) Verticals and baluns End-fed half wave J-pole Design one for 17, 15, 12, or 10 Meters The J-pole antenna, also called the Zepp' antenna (short for Zeppelin), was first invented by the Germans for use in their lighter-than-air balloons. (Traditionally fed with a balanced line at the end with only one conductor connected to the antenna. Having a two foot outrigger at the top of a 40 foot tower along with the pulley at its end has facilitated ease of changing antennas. Voltages at the output of the antenna tuner and at the end points would be very high requiring more spacing and ceramic insulators. If the far end is shorted, there is a very high impedance looking into the stub If the far end is open, there is a short looking into the stub. A fundamental list of antenna theory concepts, an antenna basics menu is given here. Antenna length and appearance are the same as those of a conventional half-wave dipole Double Zepp The Double Zepp (Doublet) antenna is a classical antenna in our series of HS4 Legendary Multiband Wire Antennas. Parallel tuning is used to minimize the complexity of the transmatch. The performance characteristics are quite outstanding. The end fed half wave antenna is a classic HF antenna. Wire antenna The $4 Special all band wire antenna G5RV G5RV Hype by K4ABT sk The Original Windom Antenna by K4ABT sk J Pole Antennas by K4ABT sk Zepp Antenna by Palomar Engineering Center Insulator ARRL No Free Lunch My Top Five Back Yard Antennas Introduction Thank you for purchasing and using the Chameleon AntennaTMHigh Frequency (HF) Base Antenna (CHA ZEPP). Later they were fed with two wires (which I generically call openwire) and called a Double-Zepp Aerial (or Antenna) because they could be viewed as being two single-wire Zeppelin antennas, fed with a common balanced feedline. Basics: The Zeppelin Antenna Electrically the “Zepp” antenna has two parts, a half-wave radiator end-fed by a quarter-wave matching section connected to the radio. Unlike typical antennas, this is a non-resonant antenna. The student will construct an extended double Zepp for 12-meters. Most published J-pole designs have been derived by making the series section, or J section, a quarter wave length long. This requires that the transmission line presents a high impedance to the Oct 10, 2015 · An excellent tutorial on the theory, construction, and use of the popular Zepp (or Zeppline) antenna. I just hope that it helps others successfully use this type of antenna since it does have some Another reason is to dispel the many antenna myths that circulate in the amateur community. The most common half-wave antenna is the center-fed dipole, whose impedance is approximately 72 ohms. Problem #1 with this theory is that this would make it a single band antenna whereas the speaker wire No Counterpoise Antenna is a multiband antenna. An antenna tuner is essential for proper operation of the center-fed Zepp. People online are saying that dipoles ideally target half wavelengths, while end feds ideally target quarter wavelengths. And may even cause electrical damage to equipment. Technically, the "J"antenna is an end-fed l l. In this video, Stan (W1GV) does an excellent job of explaining the theory, design, and operating characteristics of an antenna design going back more than 80 years. Long / Random / End-fed Antennas An end-fed wire often seems like the simplest type of antenna, but getting it to work well is actually rather complex. . Objectives and Overview: Take the student to the next step beyond the half-wave dipole and introduce wire antennas with enhanced directivity and gain. These antennas REQUIRE the use of an Antenna Matchbox on all bands. An early patent by German Hans Beggerow from 1909 illustrates the concept of an antenna equipped balloon. The larger the wire, the wider the bandwidth. The Wire Size can range from 16 AWG to 12 AWG. Even its vertical cousin, the Extended Single Zepp, seems to have changed its name to the 5/8-wavelength ground plane to avoid identification with the EDZ. Antenna systems, antennas, simple antenna formulas, basic antenna theory, feed-lines, matching units, how antennas work, polarization of electromagnetic waves, frequency, the ionosphere and modes of propagation, Ground-Wave Propagation, Direct Wave or Line of Sight Propagation, Propagation by Refraction, End fed longwire or random wire antenna Groundplane Verticals (they are generally end-fed 1/4 wave radiators) Verticals and baluns End-fed half wave J-pole Mar 11, 2024 · The Extended Double Zepp (EDZ) antenna offers higher gain than a half-wave dipole, but matching to 50-Ohm coax is difficult. 8B). Apr 30, 2025 · Here's another great antenna idea from Australia's Peter Parker (VK3YE)--a vertical double zepp antenna for 2 metres FM. It is sometimes used on its 3rd harmonic with coax, or used multiband as a doublet with balun, ladder line and wideband tuner. In actuality, theconductor is l l. The second is to use a voltage balun. It has been referred to by many different names over the years; dipole, doublet, double- Zepp, etc. ) Technical: Thebasic "J" is reported to have >3dB of gain over a l ground plane antenna and 6dB over an isotropic (theoretical)antenna. Antenna systems, antennas, simple antenna formulas, basic antenna theory, feed-lines, matching units, how antennas work, polarization of electromagnetic waves, frequency, the ionosphere and modes of propagation, Ground-Wave Propagation, Direct Wave or Line of Sight Propagation, Propagation by Refraction, The Zepp Antenna (Developed for use on the Zeppelins) was a voltage fed 1/2 wavelength antenna. In practice, it may be difficult to obtain a good match on all bands. The primary issues are: The impedance varies over a very wide range, depending on the length in wavelengths. One of the earliest examples was the Zepp antenna where the half wave antenna was end fed by an open transmission line. The "J" can be made from almost any material: copper pipe, steelwhips, and even 300 ohm TV twin-lead. That using half for end fed or quarter for dipole, results in a poorly performing antenna. Therefore, to achieve that goal, you should read this book all the way through. The radiation pattern also varies with length in wavelengths, and in some The Zepp, short for Zeppelin is any resonant antenna end-fed by ladder line. Basically, it is a somewhat random length dipole using a balanced feedline and a balanced tuner. ” Such an antenna has about 1. What if random lines start flying off of my antenna in random directions? Jan 10, 2025 · Learn all about J-Pole antenna design in this in-depth tech article, including its history, construction & best ham operating performance. Topics include directivity, polarization, bandwidth, impedance, frequency bands, all things necessary for an understanding of antenna theory, antenna basics and antenna fundamentals. It requires some sort of ground connection to work. I understand that in a half-wave center-fed antenna current distribution has a sinusoidal wave approximately, so the current in the center has max value and it has to become zero at the ends of dip a quarter wavelength, to create a broadband impedance match for a simple wire dipole, as reproduced in Figure 1. 6 dB of gain over a dipole. Remember the longer the antenna is the lower in the band it will operate , you can tune a long antenna with an antenna runer but you cannot tune a short antenna . May 1, 2021 · The End Fed Half Wave antenna or the popularly known EFHW antenna has been around almost ever since the inception of HF radio. The Classic Doublet - Open-Wire Fed Random Dipole by John LeVasseur, W2WDX One of the most efficient multi-band atennas is one that has been around almost as long as Amateur Radio has existed. 5 dBi, the model effectively has the same gain as a dipole at optimum height over typical earth! Antenna Theory • An antenna is an electrical conductor, suspended in air and insulated from ground, which either radiates or receives radio-fre quency energy. Consider the Zepp antenna first with its quarter-wave matching section. A Center-Fed "Zepp" for 80 and 40Choosing the Dimensions In order to use the antenna on 40, 75, and 80 meters, tuned feeders are required (1). Some say design for the lowest frequency you want to use, and the others say design for the Sep 25, 2014 · Extended Double Zepp AntennaA Hawaii-based Amateur Radio Antenna Blog focusing on the theory, design, and use of homemade antennas. Introduction An overview of common ham antennas for portable, base and mobile use, geared towards the new ham. This article explores a phased array design using two EDZs for directional radio transmission, achieving good gain and easier impedance matching. A Double Extended Zepp is a 3 db gain antenna . Stan Gibilisco (W1GV) does a good job of explaining how this half-wave antenna works. Center fed dipole antennas appeared, with coaxial feeders that could be easily and safely routed into the house. [2] Remember the longer the antenna is the lower in the band it will operate , you can tune a long antenna with an antenna runer but you cannot tune a short antenna . Some say any length will work, some stress odd multiples of 1/4 wavelength, while others lean toward even multiples of 1/2 wavelengths. A dipole is basically a mono-band antenna. 64 wave length elements fed in phase. It was invented by Hans Beggerow in 1909 for use in Zeppelin airships. 4 days ago · Coaxial-Cable Trap Dipole An Attic Coaxial-Cable trap dipole for 10, 15, 20, 30, 40, and 80 meters Longwire Antenna Instructions Instructions for Putting up a Long-Wire Antenna 40 thru 10 Meter Zepp Antenna A modified 20 meter double zepp wire Operating Bands: 40 thru 10 meters (with tuner), basic construction and performance information. The end-to-end length of the total wire operates as two half-wavelengths which is, by definition, a second harmonic. But why? Isn't a dipole just two end feds joined at the hip? Why come joining two end feds into a dipole suddenly flips the quarter Aug 16, 2024 · So, if the “No Counterpoise Antenna” is a variation of the Zepp, then the twinlead part of the antenna would act as an impedance transformer. ) Now there are some authors such as Moxon who challenge its theory of operation, but it is an old standard antenna in many handbooks, and is never shown with a counterpoise, or a Nov 5, 2023 · An upside down antenna! In fact the first users of this antenna routinely used it upside down – hanging from the bottom of a gigantic balloon filled with highly inflammable hydrogen gas. The third reason is a desire to teach basic antenna theory to the average ham. Oct 24, 2017 · If you want to squeeze a bit more gain out of your HF horizontal dipole antenna, you may find the Extended Double Zepp Antenna a useful alternative to the traditional 1/2 wavelength dipole. I'm a little bit intimidated. Here's an alternative explanation of how the popular Zepp (or Zeppelin) antenna works. The double extended Zepp is a dipole type Antenna consisting of two collinear 0. Extended Double Zepp NVIS Antenna Calculator The measurements below are for building a Extended Double Zepp Near Vertical Incident Skywave (NVIS) Antenna. An antenna that has always managed to end up back in this position is the 135 foot parallel fed doublet. This doublet has been tried in the A true "Zepp" antenna is an end-fed dipole that is matched by 1/4 l of open-wire feed line (see Fig 20. The simplest of these collinear arrays is a centerfed antenna one wavelength long, called “two half waves in phase” or a “Double Zepp. Stan Gibilisco (W1GV) does an excellent job of explaining the theory, construction, and operation of this antenna. xmuj csubtf zxgyms aggeth taxdq iukw rgof ydhqna owxnff bqsj uiihdbw tujen vhj iluo omkqzla