I wa tuning a j pole this evening as i have many times before but something strange happened. It was with surprise and delight that i noted that clerks in one radio. My name is michael, kb9vbr, and i carry a full line of vhf and uhf antennas for sale. Kb9vbr jpole antennas amateur radio, land mobile, scanner, low power fm, and airband antennas. Copper pipe jpole 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.
The wcxd poles in the foreground support the transmission line and the control wires. Ed fong ed fong wb6iqn gives vaca valley radio club a presentation via skype. Copper pipe j pole antenna the j pole antenna form of the zepp antenna is one of the more popular homemade vhfuhf vertical antennas. The amateur radio operator antenna basics handbook ham radio antenna, all. The yagi, j pole and nvis dipole and a glance at antenna design using 3d em software brian mileshosky n5zgt high desert amateur radio club 15 feb 20. Snapon ferrite beads 11mm set of 3 kb9vbr jpole antennas.
Trailed behind the airship, it consisted of a single element, one half wavelength long radiator with a quarter wave parallel feedline tuning stub. Kf4eoks 2 meter super jpole antenna build super j pole for 435mhz by vk6ysf the world wide web prepared by paul howarth vk2gx. The amateur radio supplies 2m70cm dual band j pole kit is the subject. Navigation kb9vbr j pole antennas amateur radio, land mobile, scanner, low power fm, and airband antennas. The theory behind these two antennas is not the same, unless someone has an acceptable, technical explanation that i have not yet found. Misek antenna research publisher of the beverage antenna handbook. Im sorry, but every post i have read that mentioned the copper j pole or zepp antenna had no comparison with the osj antenna that showed the two to be equivalent in theory, in any way. For 2 meters, the coil is 4 turns of coax at 5 inches in diameter. Buck rogers sr practical antenna handbook by joseph j.
Our uhf slim jim antenna delivers up to 6dbi of gain on the 440 470 mhz. It is simply an airship zepp antenna standing upright. A balun at the antenna base would prevent that radial effect of the coax shield and degrade overall antenna performance. The pole clamp can accept a range of pole diameters up to 2 inches.
Book depository books with free delivery worldwide. Shown is empirical evidence why this is a problem and a very simple solution all future grounded j pole antennas should incorporate. A copper pipe j pole antenna is a single band antenna that is much like a. We hang ours from some string thrown over a tree branch. The radio antenna handbook above is shown the unusual 75 meter beam antenna of w9pz. The success of the three previous editions of practical antenna handbook has been most gratifying. I dont even feel comfortable trying to make just a monoband j pole using the twin lead. Clerks in radio stores told me that this book was outselling other titles 2. An isotropic radiator is a theoretical antenna and of little practical use, except. Mirrored jpole the mirrorimage j pole is very easy to construct and requires only two tfittings plus a length of copper pipe. I found that the dimensions may vary from supplier to supplier by as much as 18 of an inch.
The main category is j pole antenna plans that is about building j pole amateur radio antennas. This also let me do a more direct comparison of j pole vs offcenter fed dipole, since i used the. The j pole antenna, more properly known as the j antenna 6, is one of the most popular antennas for 2m vertical use in the amateur radio ranks. Real measurements of a slim jim antenna and traditional jpole. The zepp antenna received a rebirth in the form of the j antenna or j pole. Kb9vbr, and i carry a full line of vhf and uhf antennas for sale.
One of the fractals used in antenna theory and design to. A practical approach to hf and vhf antennas, plus antenna. Good to get the antenna at least 10 feet off the ground. This link is listed in our web site directory since monday oct 11 2004, and till today jpole theory has been followed for a total of 29983 times. Amazons choice for j pole antop adjustable outdoor attic tv antenna mount pole, stainless painting inch arm length, reversible, lightweight, waterproof, easy installation 4. J pole antenna handbook home page ham radio antenna, ham. An antenna system is the antenna and everything else between the antenna and the radio. Use this book to discover even the most basic antenna designs wire and loop antennas, verticals, and yagisand for advanced antenna theory and. The j pole antenna, more properly known as the j antenna, was first invented by hans beggerow in 1909 for use in zeppelin airships. It is important to understand the feed line before discussing endfed antennas, or antennas like the j pole or zepp. Installerparts tv antenna j pole reversible antenna mount 1 diameter amplified outdoor hdtv antenna j pipe 20 mast satellite dish mount beige color outdoor tv antenna j mount. Try not to place the antenna close to any metal objects as well. The vertical duraluminum poles are the 14 wave vertical antennas.
The jpole antenna consists of a halfwavelength radiator fed by a. 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. Noaa weather railroad band 160 162 mhz j pole antenna. Pdf modified fractal super jpole antenna researchgate. Krauss antennas book is formerly known as the antenna bible. Probably the best book available in my view would be the arrl handbook. Dht electronics handheld antenna cable for wouxun baofeng quasheng linton adapter for uhf base and mobile antennas sma female to uhf so239 female connectors 6 pack of 2.
The jpole antenna is a common omni directional antenna used in amateur. Jpole theory the jpole antenna is an omnidirectional antenna that can be used for base, mobile and field day stations. This means meters, amplifiers, antenna switches, feed lines, etc. In this paper a super j pole antenna with two modified fractal koch curve shaped elements is proposed. 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. About jpole theory the resource is currently listed in in 2 categories. Amazons choice for antenna j pole antop adjustable outdoorattic tv antenna mount pole, stainless painting inch arm length, reversible, lightweight, waterproof, easy installation 4. It gives an unbiased, informative view of what is needed for radio transmission and reception.
What is the best book regarding antenna systems excluding. It does not need a ground plane, radials or a complicated matching system. To visualize the antenna, one must only picture a 3 halfwavelength vertical and a 2 quarterwavelength vertical positioned a few inches away from and centered on the the tall vertical. The j pole fed by a balanced line has essentially the same performance as the coax fed one, so it is the antenna receiving the wide range of freqs, not the feedline. This book was the standard many years ago, and gives a very good treatment of antenna theory. 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. The jpole can be cheaply, simply and quickly constructed using a variety of techniques, some of which are discussed in this article. Groundplane verticals they are generally endfed 14 wave radiators.
They confirmed that the types of people who buy the book meet the profile above. Pdf in this paper a super jpole antenna with two modified fractal koch curve. The j pole antenna is a 12 wave antenna with a 14 wave matching stub. Works well with handheld ht radios, base stations, and repeaters. The traditional collinear jpole, aka super jpole antenna, improves the. If you understand all the aspects of the antenna and can explain them without having to write a book, then i would like to know all the theory behind the. This one is for 2m, and as i was getting the swr very good at 144. Tame the predictable mast currents found in any jpole antenna grounding conductive mast using a simple stub. Jpole antennas ham radio, ham radio antenna, antennas. The basic j is reported to have 3db of gain over a. A good set of horizontal radials will generally out perform the cut coax to length approach.
In order to increase the bandwidth and to provide proper phasing of the currents in the. One positive point about the jpole is that its main radiating portion is high up in the middle of the top half wavelength section. A discussion of antenna theory by paul graham k9erg j pole calculator and drawing by k4abt g. It has proven to be fairly insensitive to construction methods and materials. 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. It also indicates that the j pole has been popular in mobile applications, although it is not as widely used as the quarterwave whip. A touch of class, the windom and the j pole by glynn e. Supplier of transformer cores, clips and fets used in beverage antenna construction. See more ideas about ham radio antenna and ham radio. I specialize in a certain type of antenna called a j pole.
This video takes you through the entire build process including testing. The jpole antenna consists of a halfwavelength radiator fed by a quarterwave matching stub. Amazons choice customers also shopped amazons choice for. I installed the antenna on our single story roof on a 10 foot pole. The antenna has an omnidirectional pattern with a low takeoff angle. The great thing about j pole antennas is their simple design and excellent performance. It is aimed merely by punching the proper pushbutton at the operating position inside the station. The arrl antenna book describes two common configurations of the jpole.
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