Kb9vbr jpole antennas amateur radio vhf and uhf antennas. You need to contact the server owner or hosting provider for further information. The computeraided design cad files and all associated content posted to this website are created, uploaded, managed and owned by third party users. Construction plans for a modified version of the arrow model j146440 dual band 2 meter70 cm solid aluminum j pole. Jpole antenna plans printable pdf format 800 kb this is a flexible antenna that is easy to build, inexpensive and very handy to have in your emergency communications kit. The arrl antenna book says the j pole is a halfwave antenna with a 14wl stub matching section. Kf4eoks 2 meter super jpole antenna build super j pole for 435mhz by vk6ysf the world wide web prepared by paul howarth vk2gx. Simple j antenna that will more than double your 2 meter and even 440 performance. The slim jim, designed by the late fred judd, g2bcx, can be a great portable roll up antenna, if made out of 300. Indeed, the super j will never approach the gain advantage of a properly separated two element collinear antenna, but we can get closer to this goal. Hand crafted in the usa since 2001 and thousands of satisfied customers nationwide. For vhf, the jpole became the antenna of choice, just as the. Since i had a metal fabrication background, i thought this would be an easy build.
No endorsement may be inferred from the mere listing of a url or link. Unfortunately, they all fall short by not telling readers how to tune the new antenna. Twometer antennas are small compared to those for the lower frequency bands, and the availability of repeaters on this band greatly extends the range of lightweight low power handhelds and mobile stations. The great thing about jpole antennas is their simple design and excellent performance. This optimized portable j pole antenna can greatly increase the efficiency and coverage of your ht. Ive constructed a 144440 dual band open stub j pole antenna. The radiating element of this antenna must be clear of nearby metal objects by at least inchey if side mounted on an. The j pole is one antenna that probably should not have a balun for the above reason, should you decide to try this poorly conceived antenna. The antenna plans includes design dimensions for 2 meters, 220mhz, 440mhz and 810mhz. The j pole antenna, more properly known as the j antenna, was first invented by hans beggerow in 1909 for use in zeppelin airships. Both antennas have served many hams around the globe well. Shown is empirical evidence why this is a problem and a very simple solution all future grounded j pole antennas should incorporate. Simply the best model osj 146440 open stub j pole we dont invent antennas.
Pdf modified fractal super jpole antenna researchgate. Heavyduty super sturdy 58 coupling nut for added resilience. The basic j is reported to have 3db of gain over a. A coil of 45 turns of rg58 about 4 inches in diameter seems to do the trick. Nov 12, 2009 here is a jpole antenna that i built back in november of 09.
The jpole has been around since the early days of ham radio, and is a direct descendant of the zepp. That means that mounting a two meter jpole at the top of a 10 foot pole will place the center of the radiating part of the antenna at about feet. Super j pole antenna this antenna was developed by the independent repeater association in des moines, iowa, for use on its many repeaters, nodes, and bbs. I went to the local lumberyard and hardware store a home building supply will work, as well a backpackers delight the folding jpole a new twist on the old jpole. Quick repairs to the diamond were out of the question. Make sure you use a balun fairly close to the antenna s feedpoint, though. See also the cbwhip ham j antenna by n6jsx pdf document download. It is simply an airship zepp antenna standing upright. A balun is necessary because a jpole antenna uses a balanced feed the. Images for super j pole antenna gain filetype pdf pdf super j pole antenna ndux ndux ham files pdf super% j pole pdf pdf kdoun extended super j rollanet rollanet rrars tech files twinlead superj pdf pdf copper cactus dual band super j pole antenna project meter secradio za zssrc. The super jpole antenna collinear design below is a javascript for calculating the lengths of tubing to be used for the construction of a super j pole. A touch of class, the windom and the j pole by glynn e. This antenna can be rolled up for easy portable use and will outperform a rubber ducky. A balun is necessary because a jpole antenna uses a balanced feed the 14wavelength matching section connected to an unbalanced feed line the coax.
Building the antenna i like the copper jpole, so i started a design using that antenna as a model. A practical approach to hf and vhf antennas, plus antenna. One of the most popular vhf and uhf base station antennas is the j pole. Tuning once the antenna is assembled, you can tune for minimum swr. Buck rogers sr 68 years as k4abt the jpole has been around since the early days of ham radio, and is a direct descendant of the windom like the windom or zepp, the jpole is a spinoff, or a modified windom for vhf and uhf. Copper pipe j pole antenna the j pole antenna form of the zepp antenna is one of the more popular homemade vhfuhf vertical antennas. Jun 26, 2014 this feature is not available right now. Radiowavz jp2u 2 meter portable jpole antenna with pl259 connector and carry case.
The idea of a folding version of the copper antenna appealed to me. Dbjuhf was developed from a grant from ac daughty to develop a low cost medium gain mesh antenna for uhf. It has proven to be fairly insensitive to construction methods and materials. Also see the foxhunt tips and tricks for hiding your fox at the end of the pdf file. In order to increase the bandwidth and to provide proper phasing of the currents in the. Kb9vbr jpole antennas are highly effective, affordable antennas for the vhf and uhf frequency spectrum.
Tame the predictable mast currents found in any jpole antenna grounding conductive mast using a simple stub. Each cad and any associated text, image or data is in no way sponsored by or affiliated with any company, organization or realworld item, product, or good it may purport to portray. I these currents are not minimized, the skewing is terrrible and this is the worst case for the skewing that folks tend to attribute to the j pole in general. This is what i have built for my scanner and for my radio.
That antenna is a 2x58wl phased collinear with a 12wl stub matching section. The ugly macgyver 6 meter jpole the need so what do you do when a strong wind storm finally topples your nice diamond gh6 58 wave 6 meter antenna and you want to check into the 6 meter net the next day. Construction plans for a modified version of the arrow model. Listed under the antennasjpole category that is about j pole antenna plans. Its predecessor is the famous zepp antenna developed for the zeppelin airship. The portable or base 2m70cm copper pipe j antenna by. I built the dualband jpole antenna from the article in the september. Help a newbie mountinggrounding a jpole qrz forums. Tuning a wire j pole antenna o there have been many good 2meter, or 2meter7cm j pole construction articles published in amateur radio maga tines and numerous club newsletters. By replacing the phasing stub with a simple coil, the answer is yes.
The jpole antenna is a 12 wave antenna with a 14 wave matching stub. Install the clamps and tighten the clamp fig iexploded assembly diagram of allcopper jpole antenna. While the zepp is easy to calculate, the j pole is not. Buck rogers sr practical antenna handbook by joseph j.
While there is no problem working the vari ous repeaters around town with my 14 wave antenna, simplex operation left a lot to be desired, so i felt something with a little more gain was necessary. A tri band antenna for 2 meters, 220 mhz, and 70cm antenna. Jpole antenna because the j pole and zepp are electrically identical in function, and are similar to all other endfed antennas in problems, pages on j poles, zepps, and endfed verticals overlap. J pole antenna for this station, i used a stan dard 14wave ground plane vertical antenna. The jpole antenna, more properly known as the j antenna, was first invented by hans. Building j pole amateur radio antennas category is a curation of 86 web resources on, j pole antenna for your packet radio station, the j pole antenna revisited yet again, j pole antenna for 6 meters. Construction plans for a modified version of the arrow. Here is a picture of the antenna mounted on the new mast.
I specialize in a certain type of antenna called a jpole. The jpole antenna, more properly known as the j antenna, was first invented by hans beggerow in 1909 for use in zeppelin airships. Copper dualband super jpole antenna by ka0nan, april 1993. The jpole is a slim, omnidirectional, halfwave antenna fed at the end through a quarterwave shorted transmission line.
The j pole antenna is a popular antenna design among amateur radio operators because it is effective and easy to build. J pole antenna design calculator by k4abt ham universe. All amateur radiorelated projects, tips, tricks, and tools. Buck rogers sr 68 years as k4abt the j pole has been around since the early days of ham radio, and is a direct descendant of the windom like the windom or zepp, the j pole is a spinoff, or a modified windom for vhf and uhf. The firewall on this server is blocking your connection. It contains complete build instructions plus a novel portable base stand for the j antenna. That was the used antenna, exclusively, at the helvetia contest 2012 a couple of days ago and i am very pleased with its versatility, all 9 bands, 160m to 10m. A variation of the jpole is the slim jim antenna, also known as 2bcx slim jim, that is related to. Slot antennas are familiar in the commercial radio world, but not to hams. After you receive your jpole antenna, the first question you probably have is how are you going to mount it. Tuning a wire jpole antenna american radio relay league. The radiowavz portable j pole family of antennas comes with a carry pouch and 5ft of rg8x coax. The portable or base 2m70cm copper pipe j antenna by n6jsx. The dualband openstub j pole antenna built out of heavy duty 316 angle aluminum, uhf so239 connector with 38 aluminum elements and all stainless steel hardware.
There are folks who swear that you need to ground a j pole. For 2 meters, the coil is 4 turns of coax at 5 inches in diameter. Because the velocity factor for this ladder line is different from normal 300 ohm twin lead, the traditional dimensions will not provide a good match. The j antenna goes back many years, long before i became a ham. If you like building good antennas, this one is for you. Swr should be j pole antenna act very badly if common mode currents on the mast or feed line. I built two j poles shortly after becoming an amateur radio operator. A slot antenna is a narrow rectangular opening in a large conductive surface, such as a tv satellite dish. A discussion of antenna theory by paul graham k9erg j pole calculator and drawing by k4abt g.
Experiment, create you own unique designs the j is a very forgiving, yet. Mount the antenna on a pole about 6 feet long and fasten to a step ladder or some support. The super j pole antenna collinear design below is a javascript for calculating the lengths of tubing to be used for the construction of a super j pole. Seems the 12wl stub matching section leaves something to be desired. The super jpole antennacollinear design mark twain. Sep 15, 2012 the arrl antenna book says the j pole is a halfwave antenna with a 14wl stub matching section. The j pole has no ground radials and it is easy to construct using inexpensive materials.
Mount the antenna on a pole about 6 feet long and fasten to a step ladder or some support with some rope or electrical tape. I understand that everyone else in the world uses metric, you can convert these continue reading open stub jpole project completed many times. A touch of class, the windom and the jpole by glynn e. I found that the dimensions may vary from supplier to supplier by as much as 18 of an inch. Some web sites suggest the super j has a full 3 db gain over the plain j pole which is a pretentious claim obvious to anyone with a copy of the arrl antenna book and other references1. Portable hf vertical jpole antennas the scope of requirements. Ed fong ed fong wb6iqn gives vaca valley radio club a presentation via skype. Well, the antennas themselves are pretty simple and reliable and can be installed in a. The ugly macgyver 6 meter j pole the need so what do you do when a strong wind storm finally topples your nice diamond gh6 58 wave 6 meter antenna and you want to check into the 6 meter net the next day. J pole antenna a slim jim is a type of a vertically polarized free space. Table 1 detailed parts list see fig 1 item qty part or material name no. On most of the j pole designs out there, a choke should be used as close to the feedpoint of the antenna as possible to help prevent rf on the feedline and. Trailed behind the airship, it consisted of a single element, one half wavelength long radiator with a quarter wave parallel feedline tuning stub. The basic jpole antenna is a halfwave vertical configuration.
One of the most popular vhf and uhf base station antennas is the jpole. Figure 7the completed folding jpole, ready for packing. This calculator can be used to design a slim jim or a j pole antenna. A copper pipe jpole antenna is a single band antenna that is much like a half wave dipole in that it is relatively easy to build, and when you are done you achieve the satisfaction of having built a very good antenna that works as well as expensive commercial antennas. J pole antenna dbj1 a vhfuhf dualband jpole antenna, pdf file. I built the dualband jpole antenna from the article in the september 1994 new ham companion an easy dualband vhfuhf antenna, page 61, but i just cant get it to work.
You can then start to assemble the antenna and solder the rest of the cop per jpoletwo 191. On most of the j pole designs out there, a choke should be used as close to the feedpoint of the antenna as possible to help prevent rf on the feedline and creating difficulty with swr readings. Theyre common in tv broadcasting, the skin of aircraft and in radar, microwave and cell phone applications. May 28, 2016 the traditional collinear j pole, aka super j pole antenna, improves the basic j pole. Can you use a pipe cutter or a hack saw,can you solder then here is how to build a simple j antenna that will morethan double your 2 meter and even 440 performance. I mount them on pvc pipe and the only grounding i use is the case ground on the rig. The j pole and other endfed hertz antennas are prime examples of antenna that can have severe feed line common mode current problems. I saw the plans for this on the internet link to plans by allen lowe n0imw. True plumbers delight for 2 meters an all copper j pole. In order to increase the bandwidth and to provide proper phasing of the currents in the antenna elements, the length of some elements of the. Twinlead jpole vhf antenna this is a design from an article by w9vzr in 73 magazine, august 1977, p. Its basically an endfed omnidirectional halfwave antenna, matched to.
Can you use a pipe cutter or a hack saw,can you solder then here is how to build a simple j antenna that will morethan double your 2. A copper pipe j pole antenna is a single band antenna that is much like a. Tame the predictable mast currents found in any j pole antenna grounding conductive mast using a simple stub. Page 2 introduction thank you for purchasing the alpha 6160 sr from alpha antenna. Copper pipe j pole antennas by rory eikland, kg6hcu and ken larson, kj6rz rory and i have had excellent experience building and using j pole antennas constructed from 12 inch ridged copper pipe, so we decided that we would share our experiences. Some hams have even gone to the trouble of lining their computer cabinets with metal foil. The zepp antenna received a rebirth in the form of the j antenna or j pole. Unlike a vertical dipole, which because of its center feed is usually mounted alongside a tower or some kind of metal supporting structure, the radiation pattern of an endfed jpole mounted at the top of a tower is not distorted. A vertical antenna for use on a summit which needs limited space to deploy ideally no counterpoise or groundplane wires, is light to carry and small to packup.
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