This article describes a 7540 meter nvis, but one could use the construction techniques to build just a 75 meter or a 40 meter version. It is the exact same mechanical configuration as the unit shown below, the w2au balun. 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. Originally published and by kff 5 dec 2000 on eham. The difference in gain 56 db translates into an efficiency loss of at least 50% when compared to the dipole of the same length. Build a space efficient dipole antenna for 40, 80 and 160 meters. Robert witmer, w3rw in august 1995 i came across an old clegg venus 6meter ssbcw transceiver a 1960s vacuumtube rig. I had dipoles for 80, 40, 20, 17 and 15 meters in my backyard, but they were all too low to be really very effective. The anten na shold easily handle 200300 watts pep in service. Iadeen h b very pleased with the results ofy0nd m 4 a 20 meter skeleton sleeve dipole ni arecent. The dimension length and spacing of the parasitic elements directors were.
Pdf among the radio frequency antennas, the dipole antenna or dipole aerial is one. Antenna length is usually described as wavelength wl in meters or. Build a space efficient dipole antenna for 40, 80 and 160. I now have individual 80 and 40 meter nvis antennas. Acenterfeddipoleandcanbeconstructedasamulfbandantenna. Here is a photo from dj0ip showing his 40 meter cap hat dipole below his spider beam. Wire gain antennas for 6 meters get some gain on 6 meterswithout investing in a beam and rotator.
I was hooked and immediately began construction of n6lfs antenna. This antenna is ideal for ionospheric radio wave propagation. Mike furrey wa5pok4 april 17, 2014 brandon amateur radio. Extended double zepp is simple to build, center fed antenna with 3db gain over a dipole formula. L ft 1170f mhz feed with open wire line and a tuner, this antenna will function on 206 meters may need 6 meter tuner easy to build since some tuners, especially autotuners, may have a limited. My experiment in building a vertical dipole antenna. Give your signal extra punch on amateur radios magic band. A swr meter will not provide enough information for trim tuning or feed point adjustments. I got the antenna built and up today about 35 feet.
Pdf the antenna is a key component for reaching the maximum distance. Here is the parts list and dimension sheet for a 2m square dipole, made from copper plumbing fittings and 12 inch copper water pipe. How to construct a high frequency wire antenna for ham. One of the easiest antennas to build is a traditional halfwave dipole. Here are some photos of it, before and after assembly to my 6 meter dipole. Homebrew dipole at 6 off ground on 20 meter using yaesu ft101e duration. Following an ineffective, voltagetype balun with a currenttype line isolator can greatly enhance antenna system radiation pattern and improve feed line isolation.
K0ff has a spiffy looking antenna plan presented on eham and thats the current front runner. As the name suggests, the length of the antenna is about half of the wavelength of the frequency the antenna is cut for. Taktenna antenna project n6pet my ham radio journal. You must be exact in cutting the dipole wire elements for primary frequency and harmonics to be correct. Use of a lnetwork antenna tuner, like the mfj versa tuner v model j989, allows me to tune the rest of.
This approach is almost painless, stealthy and gets the job done. The 6 meter dipole can be designed for any portion of the 6 meter band you desire using the formula. I have talked to south america, europe and all over the us with both the homebrew buddistick and buddipoles. Early in 2004 i had started working on 20 meter psk31 was and was not happy with the 20 meter dipole. This approach is almost painless, stealthy and gets the. This antenna would be good for a new tech licensee to get started on 6 and 10 meters. Hello everyone i will like to homebrew a 6 meter vertical dipole. Club vucc on 6 meters and worked all states was on 10 meters, i needed another challenge. I dont really use it much except for projects like this because cb bands have went to toilet talk and i really dont want to listen t. Download the instructional pdf at the following link. Conditions are expected to improve in the near future as solar cycle 24 progresses, so it seems a good time to add a 6 meter antenna. With a little adjusting of the ends i have better results than i expected. Strays wwii merchant marine reunion d the 1992 reunion of the gallups island radio association gira will be held at the ramada renaissance hotel in long beach, california, august 2830.
Pdf in this paper, an array dipole antenna adaptable to vhf and uhf bands was designed and constructed. The 6 meter dipole uses the same parts as the 10 meter model, less the 6foot length of. Cut the wire exactly in the middle, and attach one piece to each end insulator, just twisting it back on itself for the initial check. Wire antennas for limited space audio systems group. Pdf design of a 600 mhz dipole antenna researchgate. Then i realized that about half the length of the stinger thin metal whip was inserted into the spiralwound coil portion of the antenna. Pdf impact of the ground structure on the performance of a. The down side of lkj wednesday night special antenna design is that, because it is a shortened antenna, it is very narrow tuning from 1. In free space the centerfed halfwave antenna has an input impedance that is a close match to 50 ohm coax and to most radios that have a.
The lowest frequency at which a dipole is resonant is known as its fundamental resonance. Vertical loop an easy to install vertical loop for 806 meters. The lkj wednesday night special antenna by john whiteman. To use an antenna from 80 meters to 10 meters, the feedline should be in odd 18 wavelength multiples on 80 meters. The antenna needs two points of suspension for ropes from the dipole end insulators. The 6 meter all mode rig arrived today and i still havent put together an antenna. The design of this 6 m dipole antenna shall include the following design considerations. Radiation patterns for a dipole antenna operating at 300 mhz, 20 meters above different ground structures. Healy, antenna here is a dipole, qst, jun 1991, pp 2326. Zook, k9sth 2002, 2009 this antenna can be used either horizontally or vertically polarized. Dx engineering 300 ohm ladder line has a velocity factor vf of 0. The classic modeling approach is to treat the antenna or in the case of a dipole, each leg as an open ended transmission line in order to calculate the impedance magnitude of the antenna or the leg. A plumbers delight 3element 6meter yagi introduction.
The measurements below are for building a simple dipole antenna. For ssbcwam operation at the lower end of the 6meter band horizontal polarization is normally used. Usnerdoc kf7etx homemade 6 meter dipole antenna update project complete. Resonant halfwave dipoles range in size from about 16 feet for the 10meter band 2829. Halfwave dipole for 11 meters by 56fl114, pete a simple and certainly working antenna solution. The total length of the dipole l in meters is an electrical half wavelength.
A portable 7540 meter nvis antenna with 3209 updates by david b. Pdf design and construction of array dipole antenna adaptable to. I used the standard formula for a dipole 468 freq mhz total feet. I put up a 6meter dipole today, with results you might be interested in.
Dipole resonance is lower in frequency dipole too long. It is mostly tied to the 40 meter dipole, but on any fan dipole the elements do interact to some extent, so it can be a good idea to recheck the tuning on all bands periodically. Describe your experience with the arrow antenna gp52 6 meter 14 wave gp and tell us why you give it the rating you did required. At about 100 kc either side of 3910 and you are at 3. A plumbers delight 3element 6meter yagi introduction this construction article provides guidelines to fabricate a 6meter 3element yagi. Healy, feeding dipole antennas, qst, jul 1991, pp 2224. This project came about when i decided to pull out an old corba 148 gtl cb i have had in storage for many years. I never had a good location at the top of a hill and a rig that covered six before. If youre building a 10 meter dipole, you should start with a length of 490 28. Fabricating a jpole from copper water pipe is simple, and something ive done before for 2 meters. A length of coax will have greater losses at circle one alonger.
I dont expect it to work like a full size dipole, but for the ease of setup and take down, its working for me. After building these antennas i believe they both could be built using a good swr meter in lieu of the mfj259. I have not been able to find a solid design with the proper info on the web. I have used the w2au ansulator, which is a center insulator, without a balun. For fm operation above 52 mhz vertical polarization is normally used. Ive been using it for five years at field day and its hotter than a fire cracker. Ive looked at it several times as i have studied to plan and build my own 80 meter ocf dipole. We will look at those first, to see what good plots might look like. Is the tuning for 15 meter primarily tied to the 40 meter dipole, or, is it more spread out amongst all dipoles. Installation is easy simply connect the line isolator between the antennas balun or feed system and your coaxial feed line. The antenna is designed to be fed with 50 or 75 ohm coax cable of most any length with a balun. Short 40 meter dipole linear loaded dipole for 7 mhz.
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