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A comparison of multiband dipoles, including jumpered dipole versus fan dipole antennas, dipole fed by ladder line, resonant dipoles antennas. ARRL lab notes

Ground Plane - 1/4 wave vertical, J-Pole, 3 Element Yagi Beam and simple antenna supports

A Co-ax Trap Dipole For 40, 30 and 20 Meters or at last that was the intention

The X80 multi-band HF vertical antenna, a commercial iteration of the Rybakov design, exhibits a physical length of 5.5 meters, or approximately 18 feet, and is constructed from aluminum tubing. It operates as a non-resonant vertical, requiring an external antenna tuner for impedance matching across its intended operating frequencies. The antenna's design incorporates a 1:4 UNUN at its base, facilitating a nominal 50-ohm feed point impedance for the coaxial cable. Performance observations indicate effective operation on 40 meters, 20 meters, 15 meters, and 10 meters, with reduced efficiency on 80 meters and 160 meters due to its relatively short electrical length for these lower bands. Comparative analysis with a G5RV dipole and a half-wave end-fed antenna reveals the X80 offers a lower take-off angle, beneficial for DX contacts, particularly on the higher HF bands. Field tests conducted with an Icom IC-706MKIIG transceiver and an LDG AT-100ProII autotuner demonstrate the X80's ability to achieve acceptable SWR across 80m through 10m. The antenna's compact footprint and ease of deployment make it suitable for restricted spaces or portable operations, though its performance on 80 meters is noted as a compromise compared to full-size resonant antennas.

Software for analysis of guyed and self-supporting towers & poles

The Double Bazooka Dipole is a very efficient single band antenna which is very quite,and does not require the use of a balun. This antenna consists of coax (RG58) with the shield split at the center and the feedline attached to the open ends.

A dipole antenna for 7 MHz support for this antenna is fiberglass military mast

A small sized and very cheap antenna project that allow you to work on WARC bands with a total gain very close to the dipole in both bands. On 12 meters is a normal dipole, while on 17 is a trapped dipole. Article in Italian

A simple to build full length 20/40 dipole antenna to be used in inverted vee configuration

The collinear J-Pole, often known as the Super-J, does improve the behavior over a regular J-Pole. As many attest, there is an advantage when vertically combining 1/2 radiating sections to have a bit of separation between the half-wave end points. The Super-J has very little separation between the two half-wave radiators.

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After you have build this antenna, you may not need anything else. This article shows how to build a VHF j-pole antenna and how to protect it by inserting it into a PVC tube, the correct way.

C-Poles for 20m and 6m, it is a folded half-wave dipole with an asymmetrical tapped 50-Ohm-point in the lower part of the antenna. Design hints by DK7ZB

A conversion of a 80m dipole into a 160m vertical antenna

This is the construction of a copper cactus style j-pole antenna.

Use this online calculator to determine the length of a dipole antenna from the frequency. Both metric and English units of measurement are supported.

This web article by VK3BLG details the construction of an experimental 70cm (432 MHz) circularly polarized patch antenna, intended for satellite communication. The resource provides dimensions, feed point specifications, and impedance matching considerations for a single patch element, with discussion extending to array configurations for circular polarization. Construction involves a copper patch element on a dielectric substrate, fed via a coaxial cable. The design is based on information derived from AO-40 satellite antenna specifications, focusing on achieving circular polarization for satellite reception. The article includes specific dimensions for the patch and feed points, along with impedance values. Validation is implied through on-air satellite reception reports, with initial signal reports of **1 S-point above noise** for AO-40 beacons using a grid reflector, improving to **3-4 S-points above noise** with a 2-turn helical feed. The author references a _NanoVNA_ for impedance measurements and discusses the relationship between slot and dipole antennas in the context of patch design. DXZone Focus: Web Article | 70cm Patch Antenna | On-Air Satellite Reception | Circular Polarization

A multiband coax trapped dipole for 10-80 meters bands by DF1PU

Limiting static surges on dipoles, verticals or end fed antennas

A eham article on a square copper dipole antenna for 50 MHz by K0FF

Antenna for limited space, made from 24AWG wire helically wrapped around the top element of a 3-element cane pole, is basically a fully-loaded vertical and performance are limited and should represent the last resort for extreme cases.

A 2 meter dipole antenna by KV5R

The antenna consists of 6 runs of stranded wires spaced by plastic Hula Hoop spacers made of poly tubing

The HF horizontal loop has been around for many years now. This article includes a YouTube video and discusses the reasons for looking at this antenna, its design, and its installation. There are some on-air comparisons against three regular double bazooka (coax) dipoles and the Par SWL End-Fed antenna.

A shortened multiband dipole antenna by PA0FRI in Dutch

CB radio, Scanner, 2-way radios dealer in UK

Designing and constructing portable wire antennas for HF operations, this resource explores several configurations including the _foldback dipole_ for space-constrained setups and an inductively shortened dual-band dipole for 20m and 40m. It details the calculation of inductance for shortened elements, providing a Visual Basic 6.0 program screenshot that illustrates determining coil parameters like turns and length for a **25.5 uH** inductor. The document emphasizes practical considerations such as adjusting wire lengths for optimal SWR, noting that a dual-band dipole achieved SWR below 2:1 on both 20m and 40m, with careful adjustment bringing it under 1.5:1. Further, the resource describes a half-wave antenna matched with a coaxial stub, a method often referred to as the _Fuchskreis_ in German amateur radio circles, to transform the high feedpoint impedance to 50 Ohms. This monoband solution, for a 20m application, uses a stub length of **2.98m** (0.216 lambda multiplied by coax velocity factor) and a shorted stub of approximately 48cm. The coaxial stub design is highlighted for its resilience to ground proximity, allowing it to be rolled up or laid on the ground with minimal SWR impact, making it highly suitable for portable QRP operations.

Antenna tuners are crucial for matching the impedance of antennas to the 50 ohm output impedance of transmitters. The _LDG Z-11 Pro_ is an automatic antenna tuner designed to handle up to 125 watts, making it suitable for a wide range of amateur radio applications. Its compact form factor allows it to pair well with transceivers like the _FT-857D_, providing a portable solution for operators who frequently change locations or setups. The tuner covers the 80 through 6 meter bands, offering a broad impedance match capability. Although it struggles with some loads, it performs well with typical ham antennas, even managing to load an 80 meter dipole on 6 meters. One of the standout features of the _Z-11 Pro_ is its 8000 memory slots, which enable it to remember successful matches and quickly retune when revisiting frequencies. This memory function significantly reduces tuning time, often to less than half a second. The unit is well-constructed, with improved pushbuttons and a sturdy metal case that offers good shielding. However, users should be aware of potential RFI issues and the lack of a power switch, which requires disconnecting the power cord to turn off the unit completely. Overall, the _LDG Z-11 Pro_ is a user-friendly and cost-effective tuner, offering advanced features that enhance its utility in various amateur radio setups.

Dipole, inverted V, full wave loop and grond plane antenna quick reference plans

A post about the construction and measurements of a Resonant Feedline Dipole cut for the 10M band

Photo construction manual of a portable antenna made with two heavy duty whips by buddipole. In this article has been implemented a 50 MHz portable dipole.

Build the Slim JIM Antenna, a unique VHF Antenna with gain over a J-Pole Jose I. Calderon, DU1ANV

How to homemade a multi-band HF dipole using 100 meter of speaker wire, 2 strandsm including a homebrew 1:1 choke balun

Presents SWR analysis of an **Alpha-Delta DX-LB Plus** multiband wire antenna, installed as an inverted-V at 40 feet with ends at 15 feet, using an RigExpert AA-54 analyzer. The resource provides a full SWR sweep from 0.1 MHz to 54 MHz, followed by detailed SWR graphs for individual amateur bands including 160m, 80m, 40m, 30m, 20m, 17m, 15m, 12m, 10m, and 6m. The analysis highlights the narrow bandwidth on 80m and 160m due to loading coils, necessitating tuning for specific operating frequencies. It notes excellent SWR performance across the entire 40m band and good results on 10m, also requiring tuning. The author shares personal experience with the antenna, including a 17,000 km QSO on 20 meters, and discusses plans to replace it with a homebrewed parallel **fan-dipole**.

A comparative article on performance differences between Slim Jim antennas versus J-Pole antennas

A multi band portable link dipole antenna for 20 30 and 40 meters band

Find out how much to adjust the length of a quarter wave whip or a half wave dipole rather than the outright cut-and-try method.

Electrically shortened dipole antennas, article by Mark Connelly, WA1ION

An antenna for shortwave radio broadcasting consisting of rows and columns of dipoles, is a high gain directional antenna, designed for medium and long range communications.

All about dipole antenna construction

The resource details the construction of a multiband trap-style Inverted-V antenna designed for operation on 3.5 MHz, 7 MHz, 14 MHz, 21 MHz, and 28 MHz. It presents specific winding data for the traps, including the number of turns, wire gauge, and coil former dimensions, crucial for achieving resonance on the target bands. The document provides a parts list and a diagram illustrating the antenna's physical layout and trap placement. It outlines the process for building the traps using PVC pipe formers and specifies the required capacitor values for each trap. The design emphasizes a practical approach to achieving multiband operation with a single feedline, a common goal for HF operators with limited space. The document includes a table with antenna segment lengths for each band, allowing for precise replication of the design. It also offers insights into tuning and adjustment, ensuring the antenna performs optimally across the designated amateur radio bands.

The AB2RA bowtie 80 meter antenna includes also a 40 meter dipole

Testing performances of indoor antenna. A comparison of a magnetic loop antenna vs a classic wire dipole done using wsprlite on 30 meters band.

The fan dipole antenna as an alternative to the paralled dipole antenna, to achieve a larger bandwidth and a better tuning by decreasing elenment influences.A project based on the W6HDG original concept.

Spipral antenna principle by a concept of Bill Petlowany, K6NO. Tak Antennas are based on this principle, using spirals as dipole linear wires.

This is another alternative home-brew center connector for a dipole. The parts used are common PVC accesories found at the home supply store.

DK7ZB's fan dipole designs address the challenge of operating multiple HF bands with a single feedline, providing practical construction details for **multiband wire antennas**. The resource outlines specific lengths for half-dipoles across various band combinations, including 10-15-20m for classic bands and 12-17-30m for WARC bands. It emphasizes the importance of proper spacing between resonant elements to avoid impedance interaction and high SWR, a common issue when frequencies are too close. The article details the use of **current baluns** built with FT240-43 or FT140-43 cores, specifying turns and cable types for 1KW and 400-Watt power levels. It includes a correction table for adjusting dipole lengths based on frequency shifts, aiding in fine-tuning resonance. The 20+40m dipole is noted for its ability to operate on 15m with an ATU, demonstrating versatility.

Random Length Multiband Dipoles can be a good solution for field day operations or outdoor activity, read more at ARRL web site

Based on a simple project based on a 2 elements Yagi for 20m band, and then becomed a triband yagi with a open-sleeve feed system

Construct a compact, 20 meter rotatable dipole antenna of durable weather worthy components supported at a single point obviating the need for multiple supports and multiple support ropes crossing the yard.