Slim jim antenna ground plane. Suitable for both receiving and transmitting .

Slim jim antenna ground plane This extended version of the J-Pole antenna design does not require a ground plane and is perfect for mounting inside PVC piping. Another disadvantage is, it was the hardest to store. It's a cheap set-up because GMRS is not really all that active around here and didn't want to waste a bunch of money. The antenna has a lower takeoff angle and hence reported to have […] Oct 30, 2021 · I'm doing well with a couple of DIYed Slim Jims tuned for a few different bands. This comparison was later morphed on the Internet to be a comparison between the slim jim and a J pole. Anyone out there running indo Dengan sudut pancaran (radiation/take off angle) yang cukup rendah, Judd meng-claim Slim Jim bisa 50% lebih efisien ketimbang 5/8λ Ground Plane yang teoritis bisa menghasilkan Gain sekitar 3. Explore a wide range of antenna designs and projects for 10-meter band operation. Here we have collected some links to building instructions for 11m antennas on the Internet. Nov 10, 2014 · The gain of the humble quarter wave ground plane is a tiny 0. 5 dBd) – same as J antenna; Takeoff angle: 0 to 15 degrees depending on azimuth – same as J antenna; Requires mounting isolation – same as J antenna; Requires feedline isolation – same as J antenna; Jan 8, 2019 · I am using KB9VBR slim jim antennas, one tuned for air band and one tuned for 310 mhz. Aug 26, 2021 · I would appreciate opinions on which one and why. The J-Pole antenna became so popular in the VHF band because of its simplicity in design and construction. The radiating element is a quarter wave (λ/4) and the radials are 12% longer. Ground plane antennas are compact and should have a flexible whip. nice feature about The Slim JIM Design From the book, the slim JIM was developed based on the basic J-Pole design, see Fig. Steampunk Stick. The design for a j-pole is typically something like this (source: Ham Universe): UHF 440-470 MHz Slim Jim Antenna $ 42. Together these elements create an antenna that requires no grounding or ground plane to operate. The benefits in this case were almost entirely from a beneficial take off angle, not any actual higher gain. This suggestion is a flop. Handheld with a SMA Female in. If I'm interested in a 2m / 70cm antenna for my home's roof, wouldn't a vertical dipole be among the most obvious choices? For a half wave antenna at 2m, it should be about 1m or just over 3ft. The Slim Jim Antenna The Slim Jim is a vertically polarized omnidirectional end-fed antenna having considerable "gain" and this is concentrated almost parallel to ground toward the horizon rather than skyward making it more efficient than a ground plane type antenna by about 50 percent better. But as I'm looking around tonight, I'm wondering if an Arrow j-pole, or May 26, 2016 · Here is what SlimJIM specifications should look like: Gain: 1. Click the image to view construction details of the 70MHz quarter wave ground plane antenna. As a half wave antenna, it doesn’t require any special grounding or a groundplane to operate. 3 dBi ato = 1. 2m Slim Jim antenna made for under £10 Most people make these for 2m use, but you can make them for 70cm use Dec 15, 2018 · I'm planning on at some point down the road mounting a Slim Jim copper pipe antenna in a permanent location on a mast. This antenna design does not need a ground plane and is ideal for mounting inside PVC piping to protect it from the elements. If the stub is an obstruction then the slim jim is a good alternative. Apr 9, 2022 · For a variety of reasons, either the 1/4 wave or 5/8 wave ground plane antenna are arguably better performing antennas than the J-pole, or Slim Jim. I had tested a few rubber duckies, but the plastic box that houses transmitter Mar 12, 2017 · On flatter ground, a slim jim will perform much better than either of the other two because more of the signal is radiated towards the antenna vs up in the air. [8][23] Slim Jim antennas made from ladder Apr 7, 2023 · J-Pole antennas don’t require a ground plane (so no radials or pie pan needed), and offer significantly more gain than your standard vertical antenna. 6 dBi in the H-plane depending on azimuth (-0. I had one ground mounted and was able to hit a repeater 40 miles away with 5 watts. nice feature about I run KMR 400 with 3 or 4 ferrite snap on beads at the antenna feed point. Glad that the Slim Jim's working for you. A dipole antenna has two co-linear elements (pencil-straight) far from any conductive surface. You can design one to be relatively compact—great for situations where space is limited or to placate HOAs THE 2 METER SLIM JIM COPPER TUBING ANTENNA PROJECT BY RICHARD KE5FXU SK (Updated 1-16-2012) (Credit for the original design goes to F. Jul 24, 2021 · Greetings!!! Anyone make their own antennas for the field or for home? I cut an old homemade dipole down to 470mhz and am using it as a scanner/gmrs antenna in my shop (stapled to the outside of my shop) right now but am gathering materials to make a copper pipe/pvc vertical dipole that I can rai Uses a choke on the feedline as 'ground plane'. It gets its name from its Slim constructions and J I ntegrated M atching. Note the loading coil at the base of the antenna. The ground plane is difficult to coil up and keep neat. Slim Jim antenna was described by Fred Judd, G2BCX in 1978. 3x pancaran vertical half wave Dipole biasa. com This video dives into the design use and configurations of N9TAX Slim Jim antennas. This is strapped to a 5' length of PVC pipe, which is in turn strapped to an old (slightly rusty) video camera tripod, which is in turn standing on top of my patio table, siting on my deck. com. 3 days ago · Explore a variety of online antenna calculators for designing and calculating antenna dimensions. Slim Jim and J-Pole antenna calculator – Build a cactus for any frequency. This is a true unbalanced antenna, with a feed impedance of around 50Ω and therefore a great Jul 8, 2015 · The Slim Jim is probably one of the cheapest and easiest antennas to make, and it’s a very handy one too. The purpose of the groundplane is to ‘balance’ the antenna, that is to give the antenna something to push against as it releases the RF energy. Which antenna? Copper J-Pole Antenna by KB9VBR Slim Jim Antenna by KB9VBR BR-6140 unity gain from Browning DBJ-UHF GMRS by Ed Fong Thank your for your help. ians mass produced this antenna during the VHF frenzy in the mid-80’s. Antenna Yagi 14 elementi autocostruita per PMR446 Here is the first Yagi antenna still operating for my PMR Jun 2, 2019 · Judd found the Slim Jim produces a lower takeoff angle and better electrical performance than a 5/8 wavelength ground plane antenna. Let’s dive into the fascinating world of the Slim Jim and learn how to build one that you can take anywhere. Maritime bespoke frequencies Mar 11, 2024 · As you may have read, I’ve been working on a Baofeng-based foxhunt transmitter, and this antenna was built for this project. You can typically make one of these for under £10, they roll up easily for storage and travel, and are great for use at home, or when travelling, for accessing local repeaters. I would think that the 5/8 radiator may have slight gain advantage, but believe that the J pole may have a slightly lower angle of radiation. I plugged it into the ARRL safe exposure calculator, assuming a Feb 1, 2024 · Antenna for 446 MHz Links → 27 Antena rx Slim Jim PMR 446 Mhz This easy construction antenna has a good gain and an advantage, the vertical radiation angle is only 15 Antena Slim Jim PMR 446 de J. Initially unimpressed by some cheap 70cm whips on mag mount (not specifically tuned for 462-467) Put them in window sill on cookie sheet, and barely any improvement over standard whip antenna on HT. Technical info Slim Jim Design Enter the Dual Band Slim Jim Slim Jim Antennas incorporate an end fed folded half wave dipole and a quarter wave J integrated matching system. Find links, resources, and guides for building, optimizing, and using 10-meter antennas. 00 Are you looking for a UHF omni antenna with a little more gain? Our UHF Slim Jim Antenna delivers up to 6dbi of gain on the 440 – 470 Mhz UHF bands, which is almost twice the gain of a J-Pole and 5 times the gain of a 1/4 wave ground-plane antenna. Requires GP or radials. Aug 18, 2014 · I can’t recall a dipole or ground-plane antenna with such quality and performance currently available for the 10m-12m bands. Dec 9, 2015 · If your shack is free of any shielding, then maybe something like a ground plane antenna in the attic would work. Mar 28, 2020 · I live in an HOA, so I'm brainstorming some hidden in plain sight locations for a 2m/70cm antenna, I don't have a great deal of space in the attic, but putting a simple ground plane up there wouldn't be terribly difficult. 6 ft Diamond antenna - why so long? They also seem to have radials at the bottom, which I thought weren't needed for a The Slim Jim concentrates more RF energy towards the horizon. Thesemore Apr 21, 2012 · To answer this question, you need to look at the antenna itself. My monitoring location has a high noise floor on VHF. It is a vertically polarized half-wavelength radiator and fed with a Why is the Slim Jim so much more efficient than the popular 5/8λ or other ground plane aerials, despite the latter's claimed 3dB gain over a dipole? The Slim Jim vertical angle of radiation is almost parallel to ground so maximum radiation is where it is needed, straight out and all around. Assuming the feed line is short, low-loss, coax you're certainly better off with either antenna in the attic than an antenna attached directly to Oct 26, 2024 · Our UHF Slim Jim Antenna delivers up to 6dbi of gain on the 440 - 470 Mhz UHF bands, which is almost twice the gain of a J-Pole and 5 times the gain of a 1/4 wave ground-plane antenna. The Slim Jim, designed by the late Fred Judd, G2BCX, can be a great portable 'roll up' antenna, if made out of 300Ω or 450Ω ladder line / twin feeder. With the way these two elements are fed with your coax, no horizontal radiator elements are needed. But the options I see for sale are mostly all longer than this, such as this 5. C. Ω Ohm’s Law Calculator Ω – Enter 2 values from Voltage, Current, Power or Resistance, to find the remaining two. 70cm Slim-Jim. For example, with a quarter wave antenna The slim jim and j-pole should be the same length. I use the slim jim antennas because they are a very quiet antenna. . No interaction with the ground and the gain disappears. There are usually four radials, three being a minimum, but you could use up to six. 7 degrees higher. J-Pole or Slim-Jim antenna consists of a vertical 1⁄4-wave element and a vertical 3⁄4-wave element. It also has the spreader bars that can be easily bent in the pack or while storing. Slim Jim antennas made from ladder transmission line use the existing parallel conductor for the folded dipole element. Building and experimenting with antennas can be an interesting part of the radio hobby. The radiation pattern of this antenna is also omnidirectional and perpendicular to the plane of the antenna. I have made a page showing some images and construction details of this antenna which can be seen here. Antenna Calculator for a Collinear Dipole A collinear antenna with groundplane. This type of antenna is best when mounted above nearby objects. Aug 20, 2018 · This apparently came about when Fred Judd, G2BCX stated that the slim jim has a better TOA than a (5/8 wave) ground plane. Sold to many commercial radio stations and military installations worldwide. 100 mph+ and ice storm survival for extreme conditions. However, it should also serve well for any other 2 meter needs I have. Understanding the Slim Jim Ladder Line J-Pole Design The ladder line j-pole Slim Jim antenna represents a significant improvement over the traditional J-pole design that many ham operators are familiar with. Sep 11, 2019 · The 1/4 wave ground plane preformed well; but, it was beat out by the J-pole and the Slim Jim. 6 dBd to 0. Made in the UK by Superyagi Antennas. Requirements: 30 foot run from attic to my office (lmr400?) Mobile unit with a SO-239 in. Apr 24, 2023 · What is a Slim Jim Antenna in Ham Radio? Slim Jim antenna, as the name implies, has a very slim design and hence very little wind loading. The 5/8 wavelength configuration on 70cm will probably need a ground plane or radials though. 1 day ago · This beam antenna is a coax-feeded version of the ZL-Special construction by DK7ZB for 2m, 6m and 10m 2 meter slim jim copper tubing antenna 2 meters copper tube antenna, tested with an Icom IC-V8000 A turnstile antenna for 2-meter ARDF Antenna design for use with hidden transmitters on international-rules ARDF events 144 Mhz Magnetic Loop Vertical and Inverted L Antennas 1⁄4 wave Vertical monopole, which requires a ground plane (elevated) or a system of ground radials (ground-mounted). Of all simple vertical antennas over ground, the 5/8 wave radiator has the lowest angle of radiation, however the base of the 5/8 antenna presents a relatively low impedance, not the high impedance offered by the 1⁄4 wave stub. Related Post: J-Pole and Slim Jim Repeater Antennas. The J-Pole is a half wave antenna by design. Nov 2, 2024 · Hey folks! Trying to figure out best option for indoor GMRS antenna. For the foxhunt transmitter, I wanted a simple, portable antenna that did not require a ground plane or counterpoise. 00 – $ 46. Nov 21, 2024 · Slim Jim antenna, as the name implies, has a very slim design and hence very little wind loading. JIM stands for “J Integrated Matching” as it uses a J type matching stub. Some of the antenna projects below will take you away from our site, so click your back button to return. Sep 26, 2014 · I recently built a quarter wave ground plane antenna, so that I could get back on the 4m (70MHz) band. An omni-directional folded dipole with a quarter-wave j type matching stud. Sep 16, 2015 · Current setup: I have a Browning NMO 5/8's mobile antenna, on a browning NMO ground plane base. Slim Jim Antenna Calculator A variation of the J-Pole antenna invented by Fred Judd (UK). The calculator determines the dimensions of the antenna elements based on the input frequency. This design does not have as much gain and it showed in the testing. Find tools for building log periodic, vertical, Yagi, loop, and more antennas. It can be built for almost any frequency! ( Below 10 meters it gets VERY tall ) Due to it's SLIM This calculator can be used to design a Slim Jim or a J Pole antenna. Nov 7, 2010 · I'm currently building a 5/8 wave ground plan for 2mx as a tower based antenna, I have used J pole and slim jim type antennas in the past for the same purpose with success. Colmenar Simple quarter wave ground plane antenna for 446Mhz, all elements measure 15. Aug 4, 2019 · A ground plane antenna has a single element situated 90 degrees above an infinite conductive surface in all directions. The length of the antenna is three quarter wavelength. I have a number of KB9VBR slim jim antennas that I use for transmitting and receiving, and they all work really well. The Slim Jim Antenna The Slim Jim is a vertically polarized omnidirectional end-fed antenna having considerable "gain" and this is concentrated almost parallel to ground toward the horizon rather than skyward making it more efficient than a ground plane type antenna by about 50 percent better. 1/4 Wave Ground Plane antenna calculator – Build a simple quarter wave with radials. Due to their simple construction, J-poles are generally inexpensive and easy to build with readily available materials. 5 to 2. The MARS’. You should be fine provided it's not, you know, right next to your head. Many verticals are a 5/8 wave element, which has higher gain, lower radiation angle. Antenna Calculator for a Dual Bi-quad Antenna A 160 degree (+/-) directional antenna with gain. n9taxlabs. Suitable for both receiving and transmitting The Slim Jim antenna is an extended version of the J-Pole antenna, using the same matching stub principle. That’s why you’ll find half wave antennas mounted in difficult antenna situations, like on a boat or a vehicle roof made out of fiberglass. QUICK JUMP TO ANTENNA PROJECTS Or just scroll down so you won't miss anything! The TAK-TENNA WE REVIEW IT! Ham Radio's Limited Space HF Antenna - Now 80 Meters also! - The N9TAX 2 Meter Ladder Line Slim Jim Antenna Review Of all simple vertical antennas over ground, the 5/8 wave radiator has the lowest angle of radiation, however the base of the 5/8 antenna presents a relatively low impedance, not the high impedance offered by the 1⁄4 wave stub. 2 dBd, yang setara dengan ratio penguatan sebesar 1. Everything I've read recommends directly grounding the antenna and the mast via a ground wire to a ground rod for safety, which makes sense. Super heavy duty and commercial grade. 8cm. With all ground planes, including those with radials even one wavelength long, the vertical angle Jan 10, 2025 · Copper Cactus. 1. Check out our website! http://www. Jul 16, 2025 · The Slim Jim Antenna Calculator is an online tool that helps hams design a Slim Jim antenna for any desired frequency. Slim Jim. And also the antenna can be in Mar 3, 2024 · On 3/3/2024 at 3:44 PM, Santiam said: Yes, I have the 102, but the HT's were connected to the Slim Jim, so that should have negated the ground plane problem? You are correct on that one. Where is all the gain coming from? well it all due to interaction with the ground, with no ground lets see what it looks like. This type of antenna has gain above the standard dipole antenna, making weak signals stronger and getting a larger reach. 88 dBi down on the j-Pole and with a radiation angle of 0. Being an operator I’m sure your gain claims are realistic. Whatever you call it, the J-pole antenna is a reliable alternative to verticals and ground planes for VHF/UHF communication. Before this I built a 1/4 wave ground plane antenna out of solid copper wire and it worked really well and probably cost a few bucks in parts. Antena ini tidak familiar dan tidak ada yang memproduksi secara masal karena ya itu tampilannya tak sekeren antena hai-gain buatan Jepang dan Amerika. Judd, G2BCX) Get that signal lower to the ground for better performance! Why is the Slim Jim so much more efficient than the popular 5/8 wave or other ground plane antennas, despite the latters claimed 3dB over a dipole? The Slim Jim vertical angle of Judd reported that the Slim Jim produces a lower takeoff angle and better electrical performance than a ⁠ 5 8 ⁠ wavelength ground plane antenna, [22] however others' tests and analyses show Slim Jim antennas to have no performance advantage over a conventional, single-wire J-pole antenna. Personally I'd really want an external antenna. Jan 13, 2020 · Slim Jim Antenna merupakan antena yang cukup powerfull ketimbang antena groud-plane atau antena 5/8 lamda. May 4, 2012 · One great advantage of a half wave antenna that it doesn’t require any special grounding or a ground plane to operate. Using no less than aircraft grade, 16s gauge wall thickness for high power, and 20 years + usage Great for either ham or PMR radio 446 usage. How does your six meter antenna perform? The six meter antenna works really well. Oct 5, 2016 · The ground plane had 1-2db gain over the Slim jim when the antennas were inside the garage with the door open, the ground plane could pick up the "reference" signal better, I was a little disappointing, BUT once I moved the antennas outside the slim jim gain 2-3db over the ground plane. The advantage over just using a mobile antenna is they obviate the need for a ground plane (the ubiquitous cookie sheet), and can be hung up in a window or something like that. Aug 19, 2015 · The “conventional ground plane” he compared to the Slim Jim is a 5/8 wave antenna of some sort. Both are omni-directional. Sometimes the builder adds a stub to the bottom of the j-pole to facilitate mounting it to a mast which would make it longer. A half wave antenna doesn't need a ground plane, but sometimes it works better with a counterpoise. The Slim Jim is a vertically polarized omnidirectional end-fed antenna having considerable "gain" and this is concentrated almost parallel to ground toward the horizon rather than skyward making it more efficient than a ground plane type antenna by about 50 percent better. 4 days ago · Discover a comprehensive directory of 10 Meter Antennas on DXZONE. Ahh, the good old quarter wave ground plane! This calculator can be used to design a Quarter Wave Ground Plane antenna, with radials. yaqem macoo pgei cdnzees whzt ktdrxr moixwcom luleugvt xxsgi twlcivk ctoxw hwtqhfk lglyxi dhvdy pjbbd