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A Versatile Innovative Portable Multi-band Tunable Antenna can work HF VHF and UHF ideal as portable or balcony antenna

The Emtech ZM-2 Antenna Tuner is a nifty little portable transmatch for QRP (low power). It utilizes the well-known Z-match circuit, which is especially useful for balanced antennas (like dipoles and loops).

An experimental antenna, similar to the _TAK spiral antenna_, was evaluated for SWR response over the 7.0 to 7.3 MHz frequency range. The analysis presents specific results: beam length significantly affects SWR, with increased distance between spirals raising the resonant frequency; the combined length of antenna and hookup wire lowers the resonant frequency as it increases; and spiral diameter impacts bandwidth, with larger diameters yielding greater bandwidth. The design addresses the fixed beam length limitation of the commercial TAK antenna by introducing an adjustable version constructed primarily from PVC electrical conduit and water pipe, using 14-gauge aluminum wire. The resource includes a detailed mechanical design, construction steps, and a parts list. It also features a spiral antenna spreadsheet model for calculating design parameters like start point, pitch, safe edge, spoke length, and arm length, which aids in determining wire length and kerf cutting tables. Model verification involved constructing an antenna to specific parameters, with SWR tests conducted using an _MFJ Model 269_ antenna analyzer at 13 feet above ground with 60 feet of RG8 mini coax. Measurements showed that adjusting beam length from 27 to 37 inches shifted the resonant frequency by approximately 0.18 MHz. Further data compares 32-inch versus 48-inch diameter spirals, demonstrating increased bandwidth for the larger diameter. The model accurately predicted revolutions for given antenna lengths, pitch, and starting distances. The final design achieved a resonant frequency of 7.17 MHz, favoring the voice portion of the 40-meter band after adjustments.

Project of a windom multiband antenna for 10 to 80 meters in portuguese

ON6MU optimized 6/9 element vhf yagui antenna with antenna schematic plan and pictures of homebrewed samples.

6m to 40m EndFed Half Wave Antenna project produces an inexpensive, multiband, end fed HF antenna matchbox that is quick and easy to setup and use.

The document details the optimization and construction of the _Maria Maluca_ antenna, a compact 6-band (20m-6m) directional beam. It presents a comparative analysis of shortwave antenna principles, highlighting the efficiency gains achieved by using an open feeder line and tuner as a resonant unit, contrasting this with the losses associated with traps or capacitive loads in multiband antennas. The resource specifically revisits an older South American 2-element design for 10, 15, and 20 meters, applying modern NEC-based software to develop a six-band version. Performance data is meticulously tabulated, showing impedance, free space gain, gain at 12m height, elevation angle, and front-to-back (F/B) ratio for each band from 20m through 6m. For instance, on 15m, the antenna achieves 5.1 dBd free space gain and 13.72 dB F/B ratio. The construction section provides practical guidance on element assembly using aluminum pipes and hose clamps, detailing the use of a heavy-duty glass fiber reinforced polyamide rod for electrical separation and bending strength. It also specifies the use of 450-ohm _Wireman_ line CQ 552 for the transmission line. The document includes diagrams for rod fixing, an air-wound balun, and a vertical elevation diagram for the 15m band, illustrating its DX qualification. It also discusses the antenna's suitability for portable and expedition operations, noting its compact transport dimensions (max 1.50m length, 12 lb weight) and quick assembly time (under 15 minutes). The author, Dipl.Ing. Helmut Oeller, DC6NY, is identified as a source for material kits.

The alternative multi-band solution, covers more bands than a G5RV, light weight, won't damage your trees.

PA1G loop antenna for 80 meters band, in dutch

2 meter & 70 centimeter mobile halo antenna project, by N6TWW Mike Fedler

Ideal for QRP operations on 10 meters band in french

Various tests and designs, with photos of home made EH Antennas,simple and networked, and also sone CAN Antennas.

W1ZY's 40-meter **Moxon** antenna project details nine months of experimentation, culminating in a reversible array built from No. 12 insulated wire. The design incorporates two RF current baluns and a unique two-wire element construction, where each element consists of two parallel wires spaced 3 inches apart. The resource provides specific dimensions for the first prototype, including A=50.98', B=7.87', C=1.25', D=9.3', and E=18.42', optimized for 7.050 MHz CW operation. It thoroughly explains the construction of custom two-wire insulators from Plexiglas semi-rods and the critical pre-tensioning process required to maintain wire separation and array integrity. The author, Bill, emphasizes the antenna's exceptional receive performance, noting a 30-35 dB front-to-back ratio, which allows for significant signal rejection from the rear. While the Moxon offers 5-6 dB gain on transmit, its primary advantage lies in its ability to radically reduce rear-facing signals on receive, a characteristic Bill believes is often overlooked in transmit-focused comparisons. The guide details a flexible tuning method using removable tail-end jumpers, enabling adjustments to both tail-end and parallel dimensions without re-soldering the feed point, a technique refined over three prototypes.

A Compact size 80-10 m field day antenna offering a Low angle of radiation and very easy to build and set up

Theory, Modeling, and Practical Applications By W5JCK, presentation in PDF File. This presentation focuses on Near-Vertical Incidence Skywave (NVIS) antennas, which are crucial for short-range radio communications, particularly in military and emergency contexts. It explores NVIS theory, antenna models, and installation criteria while debunking common myths about reflectors. Key topics include usable frequency bands, optimal installation heights, and the impact of soil quality on performance. The presentation outlines the best bands for daytime and nighttime use, emphasizing the importance of understanding propagation characteristics to enhance communication effectiveness within 200 to 300 miles.

OZ1BXM 70 MHz horizontal dipole antenna

A 144 MHz six element yagi beam antenna plan

Constructing a compact UHF Moxon antenna for portable radio or TV applications demands a small, easily transportable aerial. This project focuses on a straightforward build method rather than a specific frequency design, leveraging _MoxGen_ software by AC6LA to derive precise dimensions. The author's approach utilizes an epoxy printed circuit board as the support, with traces drawn by a special felt-tip pen for soldering the antenna elements after an etching bath. For high-frequency work, particularly in the GHz range, the choice of insulating material is critical; the article emphasizes the necessity of quality UHF or SHF-grade insulation. A standard SMA connector is integrated, with one element making electrical contact via the nut and the other soldered to the central pin. This ensures a robust feedpoint for the coaxial cable. The coaxial cable, fitted with its connector, is threaded through a 12mm PVC tube that functions as a mini-mast. This tube also defines the antenna's forward direction, which should be aimed at the target signal. A sanitary clamp at the base of the tube secures it to a photographic tripod via its 7mm thread, providing a stable and portable mounting solution.

Comparison chart between Cushcraft R8, Hy-Gain AV640 , Butternut HF6V, Gap Titan and Eco 7+

For radio amateurs seeking compact, directional antenna solutions, the Moxon Rectangle offers an attractive alternative to traditional two-element Yagis. This resource compiles several articles by L. B. Cebik, W4RNL, exploring the **Moxon Rectangle** design, which provides gain comparable to a full-size two-element array but with a significantly improved **front-to-back ratio** and a direct 50-Ohm feedpoint match. The collection covers both wire arrays, particularly for lower HF bands, and rotatable aluminum beam constructions, addressing various aspects of this popular antenna configuration. The articles delve into specific band applications, including designs for 10 meters, 40 meters, and 2 meters, alongside discussions on multi-banding techniques and pattern characteristics. Comparisons are drawn between the Moxon and other antenna types, such as VK2ABQ Squares, highlighting the Moxon's advantages in terms of size and performance. Practical construction notes are provided for both wire and aluminum versions, offering insights into building these antennas for different operating environments.

Manufacturer of Fibreglass Whip Antennas, Low and mediun Frequency, HF and VHF Antennas Specialized in the design and manufacturing of a full range of Beacon (MF), AM Broadcasting 540 - 1700 KHz, HF 1.7 to 30 MHz, VHF 30 to 156 MHz and UHF 200 to 500 MHz antennas.

How to create a simple but effective half wave dipole, illustrated instrucions on how to build wire antennas

Electronic circuit and components layout fot this VHF Preamp

A compact antenna contender for 160 meters.

For two purposes a Cross-Yagi can be useful Satellite work or if you need both vertical and horizontal polarization for terrestrial contacts

160m T Antenna broadcast design by Guglielmo Marconi has been built and is used by Jim NN4AA on 160m. Article by G7LRR

Homebrewed jpole antenna for 50 mhz by IW0BZD, include pictures and schematics, in italian.

Simple DIY stealth apartment antenna for 20m and 40m. It is basically a ZigZag quarter wave dipole antenna

A simple drawing of a shortened antenna for 40 meters by using a PVC tube

pictures of a 80 mt band EH antenna by YC5NBX

Horizontal HF 6-Band turning arranging emitter with 2 elements Maria Maluca

A 40m through 20m QRO End Fed Half Wave Antenna Coupler by Steve Yates - AA5TB

An easy to build antenna for ground reception of NOAA weather or amateur satellite signals. Double cross antenna by Gerald Martes

An experimental fractal Quad antenna for 10 meter band project by AG1LE

The Chameleon V1 HF Multiband Antenna is a mobile antenna that can also be used as portable. Lightweight mil whip antenna system with 10 BANDS capability 6m, 10m, 12m, 15m, 17m, 20m, 30m, 40m, 60m & 80m.

Adalet wireless document on antenna basics in a four pages pdf file

How to extend your Wireless Network by building a 2.4 gHz wifi cantenna

Video construction of a multiband HF trapped dipole antenna based on a variation of the classic W3DZZ design

Homebrew with CF300 DGMF with about .24 dBD gain

Animated quad and yagi comparison. You can see antennas' characteristics behavior in a vertical plane with changing of the height.

Learn basic theory on antennas, and notes on homebrewing efficient shortwave antennas

This 2 meter 3 element cubical quad antenna is small, light weight and portable. A backpack antenna that is easy to put together in just minutes and parts store inside the boom making it ready for travel or storage.

Notes on homebrewing antennas by Chris G4CYA, from gamma matching, to phasing antennas, splitters and combiners, baluns and measuring techniques.

Nagara Japanese ham radio antenna manufacturer

The Double Bazooka Dipole is a half wave dipole with an attempt at compensation of the reactance change that occurs around resonance for a half wave dipole.

A quarter-wave vertical antenna design for HF operation offers a practical solution for radio amateurs seeking a compact and efficient multi-band radiator. This project details the construction of a 5-band HF vertical, drawing inspiration from established commercial products such as the _DX COMMANDER_ and the MV6. The design emphasizes ease of assembly and disassembly, making it suitable for portable operations or installations with limited space. The article provides insights into various construction methods and offers practical tips for building a robust yet lightweight antenna. It highlights the benefits of a vertical configuration for DX contacts, particularly on the lower HF bands, and discusses real-world performance observations. The antenna is designed to cover multiple HF bands, providing versatility for various operating scenarios. Operators can achieve significant DX results with this type of antenna, often comparable to more complex arrays, especially when deployed with an effective ground system. The project aims to empower hams to build a capable antenna without significant financial outlay.

21 mhz half wave ant -very low radiation angle - full size and light weight- all coax matching system - decoupling care to prevent low angle radiation degrade

A base station antenna you can easily build for 146,220 or 440 MHz, with performance similar to a J-pole but smaller and less obstrusive

An easy to build single wire antenna for 160 and 80 meters with a better than 2 to 1 swr across the 80 meter band by K5GP

This isn’t a set of step-by-step instructions, but my info might give you some ideas for building your own antenna support.