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A multiband dipole antenna that can work on 15 20 and 40 meters band made with common materials

A project for a homemade multiband Hexbeam antenna for 10, 12, 15, 17 and 20 meters

A five element quad antenna for 144 MHz DIY Project. This 2 Meter 5 Element Quad antenna was modeled using EZNEC, with a boom from a UHF TV antenna and CPVC pipe for spreaders. Constructed for 146MHz, it exhibits a gain of 10.7dB and an impedance of 75 ohms. Real-world results surpass the HT antenna, reaching over 20 repeaters up to 75 miles away. The design, costing around $10, employs simple tools for assembly.

A simple 7 bands off-center dipole wire antenna designed to work on 80 meters band and that can cover also 40m 30m 20m 15m 12m 10m with acceptable SWR

This HALO design is not ground dependent and can be mounted atop a section of PVC.

Presents a construction project for a linear-loaded 40-meter rotatable dipole, detailing the design evolution from mid-element coils to 300-ohm twinlead loading. It covers material selection, including repurposed fishing poles and EMT conduit, and outlines the assembly process for the antenna elements and mounting plate. The resource provides specific measurements for element lengths and linear loading sections, along with SWR plots demonstrating the antenna's resonance at 7.035 MHz with a 1.1:1 SWR, and bandwidth up to 7.120 MHz below 2:1 SWR. The article documents the antenna's performance during various RTTY and CW contests, including the SARTG RTTY and SCC RTTY contests in August 2006, and the ARRL DX CW and CQWW WPX RTTY contests in February 2007. It reports successful operation at 500-1000W, noting improved performance after replacing a faulty coax cable. Specific DX contacts from British Columbia, including stations in Europe and South Africa, are listed, illustrating the antenna's capability despite its shortened length and relatively low height of 55 feet. The content highlights practical considerations such as weatherproofing the connections and supporting the fiberglass elements to prevent sagging. It also includes a brief comparison to an inverted-V at similar height and a ground-mounted vertical, noting the rotatable dipole's quieter reception. The author shares insights into the iterative design process and tuning adjustments made to achieve optimal resonance.

A 10 meters band Slim Jim antenna project, made with a 450 Ohm slotted ribbon cable and secured on a 8 m fishing pole, by Steve G0KYA

Tuning the Solarcon Antron A-99 antenna for 20 meters band

A vertical portable antenna system by W0SJS that will work on 40, 30, 20, 17 and 15 meters

Compact and efficient magnetic loop antenna that cover from 40 to 10 meters project by G8ODE published by RSARS

The G5RV JR cover 10-40 meters band a project by PU2OKE

A club project experiment about a vertical Moxon antenna for 20 meter band

A 7MHz Full wave loop antenna in diamond shape for field day operations made with three 31 foot Jackite poles

Presents the design and performance of a 4-element wire Yagi antenna for the 40-meter band, building upon VE3VN's earlier 3-element switchable wire Yagi. The resource details the antenna's evolution, highlighting the transition from a 3-element to a 4-element configuration and the resulting improvements in gain and front-to-back ratio. It provides specific insights into the antenna's construction and expected operational characteristics. VE3VN shares insights from field results, noting the antenna's performance on 40 meters. The discussion includes the antenna's pattern and matching characteristics, crucial for any DXer or contester looking to optimize their signal on this popular HF band. The author's experience with the previous 3-element design informs the enhancements made to this 4-element iteration. The article includes a visual representation of the antenna's current view, offering a practical perspective on its physical layout. It serves as a valuable reference for hams considering a directional wire antenna for 7 MHz operations, demonstrating a practical approach to achieving enhanced directivity and gain.

The ZS6BKW antenna, a popular multiband wire antenna, offers improved band matching compared to the traditional G5RV. This construction guide details the process, beginning with specific dimensions: 13.11 meters (43 feet) for the 450-ohm ladder line and initial dipole arm lengths of approximately 14.8 meters each. It emphasizes the critical role of an _antenna analyzer_ for accurate tuning, particularly for determining the velocity factor of the ladder line and achieving a 1:1 impedance match. The article outlines the materials required, including a 1:1 current balun, 450-ohm window line, wire for the dipole arms, and a 50-ohm non-inductive resistor for testing. It provides a step-by-step procedure for cutting the ladder line to its electrical half-wavelength, explaining how to calculate the velocity factor using measured and free-space frequencies. For instance, a measured 50-ohm impedance at 12.54 MHz with a calculated free-space half-wavelength frequency of 11.44 MHz yields a velocity factor of 0.91. Final adjustments involve hoisting the antenna to its operational height and fine-tuning the dipole arm lengths to achieve optimal SWR, specifically targeting 14.200 MHz. The _ZS6BKW_ design is noted for its performance on 80m, 40m, 20m, 10m, and 6m, though it is not optimized for 15m operation. The author, _VK4MDX_, shares practical tips for durable construction using stainless steel wire and cable clamps.

GW4ALG's _136 kHz Pages_ document the evolution of vertical antennas for the 2200m band, starting with a prototype mounted on a house wall. This initial design, despite achieving the first **395 km** GM-GW QSO, suffered from significant insulation breakdown, high RF losses due to proximity to the house, and difficult tuning adjustments. The author details the challenges of maintaining resonance and matching with a variometer in the loft, noting that adding three earth spikes offered no measurable improvement over a simple water tap connection. The subsequent experimental 12m vertical, relocated away from the house, significantly reduced dielectric losses and proved far more effective. This antenna enabled GW4ALG to set a world DX record on 136 kHz with a **1916 km** QSO to OH1TN, and an intra-UK record of **703 km** to GM3YXM/P. The resource further explores the use of helium-filled balloons to extend the vertical radiator, achieving heights up to 27m, typically 20m, for enhanced low-band performance. Practical advice on balloon types, inflation, and critical insulation between the wire and balloon is provided, emphasizing safety and avoiding arcing.

An home made SWR meter for 2.4 GHz. A DIY SWR meter that allow precise measurements and calibration of any WiFi antenna. This is test equipment everyone who build wifi antennas should have in their shack. Article is in french and include some videos.

An easily transportable vertical antenna for 20 meters collapsible to 4 feet

The Vee Beam antenna project presents a versatile solution for hams, enabling operation across all eight High Frequency bands (80m to 10m) with significant gain on 20m to 10m. This easy-to-construct antenna utilizes two long wires at an angle, enhancing directional performance and minimizing ground losses. With a low visual profile, it is discreet and effective for various applications. The design allows for optimal leg lengths and included angles, ensuring robust performance while maintaining simplicity in construction and operation. The V Beam antenna is an aerial that you can use on all eight High Frequency amateur bands (80, 40, 30, 20, 17, 15, 12 and 10m) with an antenna tuner, and which gives significant gain on the five bands from 20 to 10 meters band.

The document provides a detailed guide on modifying an inverted-L antenna to include the 160 meters band. This enhancement allows amateur radio operators to utilize the lower frequency effectively, which is crucial for long-distance communication, especially during the night. The inverted-L design is popular due to its compact size and ease of installation, making it suitable for various environments. By adding top band capabilities, operators can engage in DXing and contesting on 160m, expanding their operational range and opportunities. The guide includes practical tips and considerations for construction, ensuring that the antenna maintains its performance across the extended frequency range. It discusses the necessary adjustments and materials required for the modification, along with potential challenges and solutions. Whether you are a seasoned operator or a beginner, this project can enhance your station's capabilities, allowing for more versatile operations and improved signal quality on the 160m band.

A 500-watt mobile antenna project details the conversion of an old 10m hamstick into a highly efficient, multiband "bugstick" for HF operation. The core modification involves replacing the original coil with 25 turns of 6 turns-per-inch, 1.5-inch diameter coil stock, fabricated from #14 wire. This design, intended for a 3-magnet mount on a vehicle cab, achieves resonance on multiple bands by shorting out specific turns on the coil, similar to a **bugcatcher** antenna. Measurements taken with an MFJ-259 analyzer on a GMC pickup show 0 turns shorted for 20 meters (14.2 MHz), 10 turns for 17 meters, 16 turns for 15 meters, 19 turns for 12 meters, and 23 turns for 10 meters. The construction emphasizes using UV-resistant tie-wraps and #14 solid wire with crimp lugs for robust RF connections, bypassing the fiberglass rod for current flow. A bonus section details a 40-meter version, utilizing 48 turns of 8 TPI, 2-inch diameter coil stock.

An end-fed halfwave antenna for 20 meters band with balun pictures and description by PD7MAA

January 1955 QST article by W5DQV about constructing a Cubical Quad antenna for 14MHz PDF File

Over 1,000 stations in approximately 60 countries were worked using this modified twin-lead folded dipole, demonstrating its effectiveness with just 4 watts on 20 meters. This design, adapted from an ARRL Handbook concept, eliminates the shorting strap found in traditional folded dipoles, simplifying construction while maintaining performance. It utilizes readily available 300-ohm TV antenna feeder ribbon, making it a cost-effective solution for radio amateurs. The antenna's robust construction allows it to handle up to 100 watts without issues, even without a **balun**. The inclusion of a variable trimmer capacitor at the stub provides flexibility for tuning across different frequencies within a band, a practical feature for operators using transceivers like the Icom 735. Formulas are provided to calculate the precise dimensions for any desired operating frequency, enabling customization for various **HF bands**.

An Off-center-feed antenna that covers 80, 40, 20, 17, 15, 12, 10, and 6 meters

A project for a home made 5 element yagi-uda antenna for 2 meters, covering 144-148 MHz band by N1BMX

3 Element reversable quad antenna for 40 meters band

If you have space constraint at your QTH for a HF antenna, you can try contructing this HF magnetic loop antenna for 40-20 meters bands

The G5RV multiband HF antenna, designed by Louis Varney (G5RV) in 1946, is a popular compromise antenna offering good overall performance on most HF bands when paired with an external antenna tuner. The basic full-size G5RV measures 102 feet across the top for 80 through 10 meter operation and is fed at the center via a 34-foot low-loss feed-stub. This interaction between the radiating section and the feed-stub facilitates matching across 80-10 meters with a standard tuner, often eliminating the need for ladder line directly to the shack. The antenna's design center frequency is 14.150 MHz, configured as a 3/2-wave dipole on 20 meters, with its 102-foot length derived from long-wire antenna formulas. Construction details emphasize the matching section, which can be open wire, ladder line (window-type), or TV twin lead. Each type has a specific velocity factor (VF) affecting its physical length for an electrical half-wave on 14 MHz; for instance, open wire requires 33.7 feet (VF 0.97), ladder line 31.3 feet (VF 0.90), and TV twin lead 28.5 feet (VF 0.82). The article provides formulas for calculating these lengths and discusses the antenna's behavior on individual bands, from 3.5 MHz where it acts as a shortened dipole, to 28 MHz where it functions as two three-half-wave long-wire antennas fed in-phase. Practical construction notes include recommendations for vertical descent of the matching section, sealing the coax junction, providing strain relief, and winding a coaxial choke coil to mitigate common mode current. The resource also presents dimensions for double-size (204 ft) and half-size (51 ft) G5RV versions, along with their corresponding matching section lengths for various line types, making it a versatile reference for hams considering this classic wire antenna.

A trapped dipole antenna based on the orignal W3DZZ antenna design resonating on 80 40 20 15 10 meters

An homemade portable trapped dipole antenna for 40 and 80 meters band with an optional extension for the 20 meters.

Extension to an existing fan dipole originally modeled for 40 20 and 6 meters. This modification will add 80 15 and 10 meter bands.

An end fed 20 meter half wave antenna

2 Meter Indoor Slim Jim Antennas for Cyclone Season and Other Uses by VK4MDX

A 5 band two element quad antenna working from 20 to 10 meters using hardware-store parts or modifying an existing commercial triband quad by KC6T

A vertical antenna for 40 meters band by PA5MW

Optimizing a G5RV or ZS6BKW multiband wire antenna for HF operation often involves addressing common SWR issues and understanding feedline characteristics. This resource chronicles the construction and performance evaluation of a G5RV, initially built for 80m, 40m, 15m, and 10m bands, by a newly licensed Foundation operator. The author details the selection of materials, including 3.5 mm stainless steel wire for the doublet arms and enameled copper wire for the open-wire feeder, and the initial decision to omit a balun based on common online information. The narrative highlights the initial disappointing performance, characterized by high receive noise and poor signal reports on 80 meters, despite the transceiver's internal ATU achieving a 1:1 match. This led to experimentation with a coax current balun and further research into G5RV myths, such as SWR claims and the necessity of a balun. The author then describes modifying the antenna to the ZS6BKW configuration, which involves specific changes to the doublet and feedline lengths, and integrating a 1:1 current balun wound on a ferrite toroid. The modifications resulted in improved reception and transmit performance across the bands.

Homebrew a 2 meter square dipole antenna

Demonstrates the construction of a 144 MHz turnstile antenna, detailing its design for omnidirectional, horizontally polarized VHF operation. The resource outlines the physical dimensions and materials required, including specific lengths for the radiating elements and the use of _RG-58_ coaxial cable for phasing. It covers the assembly process, emphasizing the critical spacing and connection points to achieve the desired radiation pattern and impedance matching for the _2-meter band_. The article presents measured _SWR_ performance across the 144-146 MHz segment, showing a low SWR of 1.2:1 at 144.5 MHz, which is suitable for general VHF use. It compares the turnstile's performance to a 9-element Yagi, noting the turnstile's advantage in providing consistent signal strength from all directions without requiring a rotator. Practical application for local FM simplex and repeater operations is implied, offering a simple yet effective antenna solution for fixed or portable stations.

G0KYA Moxon antenna for 2 meters band

Experiments with spiral dipole antennas. Includes two spiral antenna designs for 20 and 40 meters band by KN9B

The ZS6BKW multiband antenna, an optimized variant of the classic G5RV, features a 102-foot (31.1 m) horizontal span and a 39.1-foot ladder line matching section. This design, derived by G0GSF (formerly ZS6BKW) in the early 1980s using computer programs and _Smith charts_, aims for improved SWR across multiple HF bands compared to its predecessor. Construction details specify Wireman 554 ladder line and #14 AWG THHN copper wire for the radiators, with precise instructions for determining the velocity factor (VF) of the ladder line using an antenna analyzer or dip meter, ensuring accurate physical length for the matching section. The radiator length is electrically 1.35 wavelengths for the 20-meter band, requiring careful trimming during tuning. Field measurements with an _AIM-4170C_ analyzer by KI4PMI and NC4FB demonstrated good SWR curves and bandwidth on 6, 10, 12, 17, 20, and 40 meters. The antenna was deemed unusable on 15 and 30 meters due to very high SWR, but an LDG AT-100PRO autotuner successfully brought 6 and 80 meters into tune. Contacts were made on 80, 40, 20, and 17 meters, including a **17-meter** contact to Spain. EZNEC models for 80-6 meters are provided, along with an AutoEZ model by AC6LA, which predicted good SWR for 80-10 meters. W5DXP's modifications for an all-band HF ZS6BKW are also referenced.

40/20/10 Meter Fan Dipole attic antenna article by KD2GOE

Exagonal Beam antenna cover 20-17-15-10 meters By KE4NU

An homemade fan dipole antenna for 20 30 40 meter bands, setup in a 15 meter wide garden. The longest leg for 40 meter is folded to fit in the 7.5 m

Demonstrates the construction and implementation of a **two-element phased vertical array** for 40 meters, utilizing _Christman phasing_ techniques. The author, W4NFR, details the process from building individual 1/4-wave aluminum verticals to integrating them into a phased system. The resource covers antenna spacing of 32 feet, elevated radial design, and the critical steps for tuning each vertical to achieve a 1.1:1 SWR before combining them. It also provides insights into calculating precise coax lengths for feedlines and the phasing delay line, emphasizing the use of an MFJ-269 Antenna Analyzer for verification. The finished system exhibits good front-to-back nulls, with an overall SWR ranging from 1.6:1 to 2.2:1, which is managed by an antenna tuner. The project includes detailed photos of the relay box, showing 12 VDC relays capable of handling 5KV, and the control box in the shack for switching between three different antenna pattern configurations. Static bleed-off chokes are incorporated for protection, and the construction emphasizes robust weatherproofing for outdoor elements.

This project details the construction of a **full-sized 40-meter vertical antenna**, born from a renewed interest in 7 MHz operation and a desire for improved effectiveness over simple dipoles. The author, K5DKZ, initially focused on VHF experimentation, which provided an inventory of aluminum tubing and fiberglass spreaders for this endeavor. Before this vertical, K5DKZ utilized an 80/40 meter inverted-vee trap dipole and a 40-meter broadband dipole, but now primarily uses a pair of full-sized, phased, quarter-wave verticals spaced 35 feet apart for serious 40-meter work. The construction involves a base-heavy design for stability, using a 44.5-inch section of 1-1/4 inch steel TV mast driven into 1-3/8 inch aluminum tubing, insulated by a 105-inch section of Schedule 40 PVC pipe. The assembly reaches 31 feet, close to the 32 feet required for a quarter-wavelength on 40 meters, with fine-tuning achieved by winding wire onto a fiberglass spreader. The design is explicitly presented as a foundation for a two-element 40-meter Yagi beam, outlining modifications like substituting aluminum for steel in the base and using an inductive hairpin match for the driven element. The article also discusses tuning considerations for a large 40-meter beam, noting the 100 to 200 kHz upward frequency shift when raised, and suggesting methods for installation on a tower. The author emphasizes the cost-effectiveness and good performance of the monopole approach, especially when multiple verticals are needed.

G0KYA review of the EH antenna for 20 meters band

Experiments with an 80 meter Inverted L Quarter wave antenna

An home made slim jim antenna for 2 meters band by VU2TQC