I built two jpoles shortly after becoming an amateur radio operator. The j pole antenna build one for the hf bands 17, 15. The main category is j pole antenna plans that is about building jpole amateur radio antennas. Amateur radio toolkit for android free download and. 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. If the antenna is to be placed outside, do not use brass. The great thing about jpole antennas is their simple design and excellent performance. Matching to the feedline is achieved by sliding the connection of the feedline back and forth along the stub until a vswr as close as possible to 1. In the middle are the two antenna whips, mounted in some cpvc with speaker wire coming out of the. Jpole antenna because the jpole and zepp are electrically identical in function, and are similar to all other endfed antennas in problems, pages on jpoles, zepps, and endfed verticals overlap. Optical investigation of the jpole and vee antenna families osa. For 2 meters, the coil is 4 turns of coax at 5 inches in diameter. An integrated antenna is included in the pole, as part of the pole structure, not mounted on the exterior, and its another exciting piece of ip developed by philips lightning.
Arrl handbook says it works best at the antenna if you are using it for rf isolation. The jpole antenna is much more popular on vhf because it ends up being a long antenna on hf, it isnt all that popular however, on the 11m band, the jpole still has a managable length 27 feet. Jpole antenna and picked up what i needed to make the portable antenna project a reality. It is an implementation of one of the oldest antenna designs. Editors can experiment in this templates sandbox create mirror and testcases create pages.
Feedline and feedpoint effect on pattern of jpole antenna. Tame the predictable mast currents found in any jpole antenna grounding conductive mast using a simple stub. Pdf a microstrip asymmetric folded dipole antenna on chip is proposed in this paper. Each super jpole antenna element provides a high directivity where. New led smart streetlight pole from philips lighting could. A little searching around essex pack identified a tree with some open space to the south.
Also it is very important that you never cut the white cable on the new mast at any time. Just to make my position on the jpole clear, i hate them. An allcopper 2m jpole rigid copper tubing, fittings and assorted hardware can be used to make a really rugged jpole antenna for 2 m. The super jpole antennacollinear design mark twain. This shortened easytobuild vertical, with noradials, is made from surplus military camouflage poles. Evla memo 172 the modified jpole antenna nrao library. Just what is a dipole antenna, and why are they so popular. All amateur radiorelated projects, tips, tricks, and tools.
My antennas have a low noise floor and a beautiful omnidirectional radiation pattern. I specialize in a certain type of antenna called a jpole. Tuning a wire jpole antenna american radio relay league. This memo describes the modified jpole mjp, a broadband endfed dipolelike antenna that was developed at virginia tech and. This antenna can be rolled up for easy portable use and will outperform a rubber ducky. Pdf wideband blade monopole antenna with sleeved coaxial feed.
Being a halfwave antenna, it provides a small gain over a. Simplicity and effectiveness for a wide range of communications needs are. Pdf a wideband planar monopole antenna requiring a small ground plane is described. The text explains how to adjust it for minimum swr. The jpole antenna, also called the zepp antenna short for zeppelin, was first invented by the germans for use in their lighterthanair balloons. The jpole antenna is an endfed omnidirectional dipole antenna that is matched to the feedline by a quarter wave transmission line stub. A practical approach to hf and vhf antennas, plus antenna. 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.
Antenna miniaturization using slow wave enhancement. These files are copywritten by the arrl and are public domain. Unfortunately, they all fall short by not telling readers how to tune the new antenna. One flag pole manufacturer says put it at the house so the coax can couple to the ground as a radial. Since the antenna needed to be vertically polarized, i hit upon the notion of a jpole. Heres the straight scoop on why the jpole is not an easy antenna to duplicate. Jpole antenna everybody says keep one in your bag, nobody seems to make one work right. Essentially, a jpole is a 12 wave resonant antenna connected to a quarter wave matching stub. 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. To their right is the t component for mounting the antenna on a painters pole. Its predecessor is the famous zepp antenna developed for the zeppelin airship. Tie the antenna lead 24 of 14 stranded wire on to twine and when the antenna is at the top of the flag pole, pull the antenna lead out of the hole. These are downloadable open file and use the save button in pdf reader.
Copper dualband super jpole antenna by ka0nan, april 1993. Jasik, editor, the antenna engineering handbook chapter 3. Trailed behind the airship, it consisted of a single element, one half wavelength long radiator with a quarter wave parallel feedline tuning stub. I merely hung one cpole in that tree and set my self supporting cpole about 44 58 wavelength on 14. The one problem is that there arent very many free pdf editors. A simple jpole antenna was studied to get an idea of the extent that changes in feedline length or conducting support structure would make on the pattern. High performance 40 meters vertical without radials. Use our diagram editor to make flowcharts, uml diagrams, er diagrams, network diagrams, mockups, floorplans and many more. A balun is necessary because a jpole antenna uses a balanced feed the 14wavelength matching section connected to an unbalanced feed line the coax. Amateur radio toolkit is the best app for ham radio hobbyists. Kf2yn cpole the c polea ground independent vertical antenna, brian cake, kf2yn, qst, apr 2004 omni directional low angel of radiation performs well with no ground system ground currentsloses greatly reduced over a ground mounted vertical for 20 mtrs 40.
The roach pole is very light allowing the 4 radials and the 3 light nylon guys to be secured with tent pegs 5. I have seen this basic diagram in at least five different sites. The antenna plans includes design dimensions for 2 meters, 220mhz, 440mhz and 810mhz. The jpole is a slim, omnidirectional, halfwave antenna fed at the end through a quarterwave shorted transmission line. The black adapter changes the threads from pvc to the painters pole. For 3meters fm broadcast band it is probably the antenna that is the best solution for many micro power radio stations. Kinsner, ve4wk jpole antenna for 2m 3 of 3 1 2 3 4 5 6 7 8 e d c b a e d c b a 1 2 3 4 5 6 7 8 5 june 1992 jpole parts list procedure p2 m1. The dualband openstub jpole antenna built out of heavy duty 316 angle aluminum, uhf so239 connector with 38 aluminum elements and all stainless steel hardware. This web page created with pagebreezmeasurements editor antennas reflectionswiicompendium. This memo describes the modified jpole mjp, a broadband endfed dipole like antenna that was developed at virginia tech and. Experiment, create you own unique designs the j is a very forgiving, yet.
Power antenna mast instructions, the antenna source. Before installing your new mast, compare the old mast with the new one. Both antennas have served many hams around the globe well. If you like building good antennas, this one is for you. The super jpole antennacollinear design below is a javascript for calculating the lengths of tubing to be used for the construction of a super jpole. I wanted high efficiency 40 meter antenna with lowangle radiation.
The jpole and other endfed hertz antennas are prime examples of antenna that can have severe feed line common mode current problems. This does not mean that the antenna will not work at all off the ends but the gain will be less. Basics the antenna consists of a vertical halfwave dipole that has been folded virtuthe c pole a ground independent vertical antenna kf2yn takes the vertical to new heights with this folded design that doesnt require a counterpoise. We would like to show you a description here but the site wont allow us.
Heavyduty super sturdy 58 coupling nut for added resilience. This antenna was patented in 1909 by the german, hans beggerow. The jpole antenna is a common omni directional antenna used in amateur radio, particularly on the vhf and uhf bands. Super jpole antenna this antenna was developed by the independent repeater association in des moines, iowa, for use on its many repeaters, nodes, and bbs. 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. Vhfuhf antenna, page 61, but i just cant get it to. Vhfuhf antenna, page 61, but i just cant get it to work. The great thing about j pole antennas is their simple design and excellent performance. Matching to the feedline is achieved by sliding the connection of the feedline back and forth along the stub until an impedance match is obtained. The necessary parts for this project can be found in table 1, and figure 1 can be used as a basic assembly guide for building the antenna.
The jpole antenna is best understood as a bent dipole antenna. Building jpole amateur radio antennas category is a curation of 86 web resources on, jpole antenna for your packet radio station, the jpole antenna revisited yet again, j pole antenna for 6 meters. Other very good j antenna designs published in 73 magazine have been. Jpole antenna plans the jpole antenna is fundamentally an endfed 12wavelength antenna that uses a 14wavelength long transformer section to supply the very high feed voltage. The j pole antenna is a 12 wave antenna with a 14 wave matching stub. This link is listed in our web site directory since monday oct 11 2004, and till today easy jpole antenna has been followed for a total of 34577 times. The jpole antenna is an endfed omnidirectional halfwave antenna that is matched to the feedline by a quarter wave parallel transmission line stub of lecher system form. Usually the antenna is mounted using a rotator so that you can rotate the antenna for maximum gain. Feedline and feedpoint effect on pattern of jpole antenna and input impedance. The jpole antenna is a 12 wave antenna with a 14 wave matching stub. Antenna here is a dipole youve probably heard this phrase in many qsos.
Pdf microstrip folded dipole antenna for 35 ghz mmw. 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. Online physics calculator that calculates the long, short section, feed point, spacing dimensions values for current frequency. Tuning a wire jpole antenna o there have been many good 2meter, or 2meter7cm jpole construction articles published in amateur radio maga tines and numerous club newsletters. I specialize in a certain type of antenna called a j pole. If you find any other interesting links or information, let me know and i will include it here. Further, the four super jpole elements with a switched operation can cover the. How to build your own dmr digital radio code plug kb9vbr. About easy jpole antenna the resource is currently listed in in a single category. You will first need to cut five 191 4 inch sections and one 23 4. I already have one self supporting 20 mtr cpole antenna. They look pretty weird, as can be seen in the following photo. To support the antenna, lash it to a piece of pvc pipe with uvresistant nylon cable ties. A touch of class, the windom and the jpole by glynn e.
The zepp antenna received its name from its use on zeppelin airships. Peiling chi, student member, ieee, rod waterhouse, senior member, ieee, and. The jpole is one antenna that probably should not have a balun for the above reason, should you decide to try this poorly conceived antenna. Unlike the popular ground plane antenna, it doesnt need ground the dbj2.
Open and save your projects and export to image or pdf. A read is counted each time someone views a publication summary such as the title, abstract, and list of authors, clicks on a figure, or views or downloads the fulltext. Shown is empirical evidence why this is a problem and a very simple solution all future grounded jpole antennas should incorporate. It contains many calculators to help you design radios and antennas for all your projects. The picture to the right is of a 2m amateur radio band jpole i built from an eznec simulation. If they are different, you may have an after market power unit. The earlier dbj1 is based on the jpole,2 shown in figure 1. This is because adobe, the original creator of the pdf format, actually still owns. Bus healy, nj2l assistant technical editor ipole antennas have been widely used since the early days of radio.
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