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This scheme can be used to combine two antennas

The ZS6BKW multi-band antenna, an optimized variant of the classic G5RV, is presented with detailed construction and tuning instructions. This resource outlines the antenna's design principles, which were developed by _Brian Austin (G0GSF)_ using computer programs and Smith charts to achieve optimal dimensions. It provides specific guidance on calculating and adjusting the lengths of the radiators (L1) and the matching ladder line (L2), emphasizing the critical role of velocity factor (VF) in achieving resonance. The article includes a step-by-step procedure for empirically determining the VF of ladder line using an antenna analyzer, ensuring accurate physical lengths for the matching section. It details the tuning process for the radiators, offering practical tips for incremental adjustments to achieve the best SWR curve. The resource presents SWR measurement results obtained with an _AIM-4170C_ analyzer across multiple bands, alongside predicted SWR graphs from an AutoEZ model. It confirms successful contacts on 80, 40, 20, and 17 meters, including a **17-meter DX contact** to Italy. EZNEC and AutoEZ models for the ZS6BKW antenna, covering 80 through 6 meters, are provided for download, allowing further analysis and customization. The document specifies component details, such as the use of Wireman 554 ladder line and #14 AWG THHN copper wire, and discusses the antenna's performance characteristics, noting high SWR on 15 and 30 meters but successful tuning on 6 and 80 meters with an external tuner.

A short multi-band vertical antenna

Some basic antenna information for the newcomer

80 to 6 meters, 2 KW, designed to be used at heights of only 25 to 45 feet, includes a twenty foot long vertical radiator

How to build a phasing harness for stacking antennas

A VHF UHF handheld antenna suitable for satellite operation by LY3H include antenna plan with dimensions and pictures.

A 4-Band vertical antenna that needs NO tuner, NO traps. Implement an LC matched on 4 bands with relay switching.

DL7JV Christian report his direct experience on magnetic antennas

An interesting article on how to make copper cactus J-Pole antennas

Isolation vs antenna separation an interesting article by WA6ILQ

A three band short Vee antenna is feasible with two legs per side on a dipole. 10-15-20 meters by W8HDU

Dish antenna and its theory and design for high performance applications such as satellite transmission and reception as well as microwave links. Parabolic Reflector Antenna: Dish Antenna The parabolic reflector antenna which is often called the dish antenna provides an antenna solution applicable for VHF and above where high gain and directivity are needed for all type of radio communications and radio reception.

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

Dragoslav Dobricic, YU1AW antennex article on influence of Boom on frequency performance and how compensate it

The Double 5/8 is a natural extension of the Single 5/8 and uses a 5/8λ element for both the top and bottom radiators.

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

6 Meter 1/4 Wave Antenna by Mike Fedler N6TWW. A detailed article with pictures of construction details of this 50 Mhz antenna

A 144 Mhz Slim Jim Antenna, aluminum tubing version project by Mohammad 9W2WTF

Phased wire vertical antennas for 40 meters band

A spiral antenna experiment for RTL SDR usage.

An homebrew Lindenblad antenna designed specifically for LEOs reception.

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.

An experimental omni-directional antenna for 70cm which has both horizontal and vertical gain

A simple antenna analyser for the HF spectrum with a built-in signal generator with 3-digit LED frequency display.

Quarter wave omni-directional spider antenna for 2.4GHz 802.11b

Comments received from QRP-L members concerning their experiences with GAP antennas.

A compact 2 element W8JK beam antenna for 20M to 10M bands by AF6SA

The antenna described here is a direct-connect dual-rectangle beam for use on 70 cm between 440 and 450 MHz

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

A vertical antenna for Six Meters band

Extend the range of wireless network or connect to other wireless networks in neighborhood with your own wifi antenna.

An article at NFARL web site about differences in setting up a half-square antenna versus a Loop Skywire by W4QO

A K9AY loop antenna project done with Far Circuits pc boards for the antenna switch and bandpass filter and preamp by K7SFN

Article by VU2GT about VHF antennas, how to evaluate performances and models.

Mounting on Roof or at Ground Level? Why ground plane antenna works better at lower level.

Constructing a compact, single-feed triband Moxon antenna for 20, 15, and 10 meters is detailed by DU1RZ, drawing from his personal experience with space-constrained antenna projects. Initially fascinated by cubical quads, the author transitioned to Moxon designs in 2005 after realizing his roof space was insufficient for a bulky quad. His first experimental monoband Moxon for 15 meters, built from repurposed materials, provided solid DX QSOs for seven years, despite being slightly below the 21 MHz band center. The project outlines the design process, including using the _MOXGEN Calculator_ for element dimensions and material selection, such as #14 AWG enamel copper wire and fishing poles for spreaders. DU1RZ shares insights from simulations with DL2GMS regarding insulated versus non-insulated wire performance, noting that insulated wire can shift resonant frequencies lower. The assembly instructions cover preparing wire elements, connecting feed points, and tuning the antenna, with initial SWR measurements taken at 10 feet and final readings on a mast showing excellent results: 1.0:1 on 14.225 MHz, 1.1:1 on 21.250 MHz, and 1.3:1 on 28.50 MHz. Transmission tests with 4F1BYN indicated a front-to-back ratio of approximately 2 S units with 10 watts output. The author emphasizes adaptability, encouraging builders to use readily available materials rather than strictly replicating his setup. Key observations from DU1RZ and DL2GMS highlight the antenna's strong performance across 20, 15, and 10 meters, good front-to-back ratio, full bandwidth on 20 and 15 meters, and its small turning radius of about 4.18 meters (13.54 feet), making it suitable for limited antenna space. Its lightweight construction and low wind load are also noted as significant advantages.

This site serves a community of volunteer and paid professionals in Search & Rescue and Civil Air Patrol who save lives and Amateur Radio enthusiasts who use DF skills as a hobby. We provide antennas and other resources for people in these fields.

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

An HexBeam antenna project, a 2 full elements on six bands

The electrical characteristics of an antenna that are of interest to obtain by direct measurement are the frequency at which the antenna is tuned, the gain and radiation pattern

A four elements quad antenna for 144 MHz made with PVC pipes

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

A step by step approach for a ham radio vertical antenna mount using only a hole, gravel and a piece of plumbing pipe

General article on Baluns at myantennas.com, what is a balun and when to use baluns

Demonstrates various practical amateur radio projects and technical discussions through video episodes. One episode details cutting and retuning a _1/4 wave shorted stub_ from 101.7 MHz to 107.5 MHz to safeguard a transmitter's driver stage, alongside insights into advanced _160-meter antenna systems_ like eight-circle arrays and beverage antennas. Another segment covers upgrading firmware on an _ATS-20+_ receiver using AverDudes for improved display and functionality, and a detailed guide on using D-Star DR mode on an _ICOM ID-52A_ for international repeater programming. Additional content includes a deep dive into _OpenHamClock_ as a potential replacement for the HamClock project, updates on _Raspberry Pi 5_ running Trixie OS, and a review of the Choyong LC90 Internet radio with AI integration. The series also features "Ham College" episodes, which meticulously prepare viewers for the Technician Exam by covering topics such as antenna and transmission line measurements, SWR interpretation, and the functions of basic electronic components like rectifiers, relays, and transistors. Practical advice on coaxial cable characteristics, dummy loads, and proper soldering techniques is also provided.

A page dedicated to the Quadrifilar Helical Antennas, with projects, pictures and antenna plans by OH2GVB

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.

This resource details the construction of a portable antenna tripod designed for supporting small vertical antennas, utilizing readily available electrical metal tubing (EMT) or conduit. It outlines the necessary components, including a custom-fabricated _EARC tripod plate_, standard hardware, and a 10-foot section of 1/2-inch EMT cut into specific lengths for legs and a center support. The instructions cover assembly of the tripod plate, leg construction, and integration with a fiberglass fishing pole like the _Kwik Stix_ or _Shakespeare Wonderpole_ to support a vertical wire HF antenna. The project also describes an adaptation for using the tripod with 3/8x24 threaded mobile antennas such as _Hamsticks_ or _Buddisticks_, where the tripod structure itself contributes to the antenna's counterpoise system. A complete parts list is provided, along with ordering information for the specialized EARC tripod plate, which serves as a fundraiser for the Honolulu Emergency Amateur Radio Club. The document includes photos illustrating the assembled tripod and its use with a fiberglass pole.

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.