End Fed Half Wave Antennas: Builds and Information
Find schematics, construction guides, and performance insights for various end-fed half-wave antenna configurations.
End-fed half-wave (EFHW) antennas are popular with hams for their simplicity and versatility, especially for portable operations and limited space installations. Unlike center-fed dipoles, EFHWs are fed at one end, which often simplifies deployment and reduces feedline clutter. These antennas are resonant on their fundamental half-wave frequency and can often be made to operate on harmonic bands with a suitable matching unit.
Many operators build their own EFHW antennas for various HF bands, from 80 meters down to 10 meters. Resources here cover designs for single-band operation, like a 20m EFHW, as well as multiband versions using matching networks. You will find projects for building matching units, often incorporating toroids like the FT140-43, and discussions on optimizing antenna length and counterpoise requirements for good SWR across the bands. These designs are frequently used for QRP transceivers and SOTA activities, allowing hams to make QSOs from remote locations.
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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. -
An end fed 20 meter half wave antenna -
20m end fed half wave vertical antenna -
A Half wave antenna has a high impedance feed point. This can be matched using a 1/4 wave stub matching section and converts the 40m vertical into an L-shaped 20m J-Pole antenna. The 300 ohm feeder used for this purpose must be kept away from the ground. -
This article is about a simple vertical end-fed-half-wave wire antenna for 10 meters that can be used in case of restricted space. -
In this experiment the autor is going to explore the use of a 1:64 matching network on the End Fed Long Wire Antenna. Experiment will consist in build a 80-40-20-15-10 meter End Fed Long Wire Antenna with a 1:64 matching network from the documentation available on the internet -
For my SOTA activities, i recently bought a QRP transceiver QRP SW-3B, which is a three-band QRP CW only for 40/30/20 m. So, i needed an antenna that would allow to use these 3 bands in SOTA portable activity. Already having some experience with the EFHW antenna, i decided to build one for 40/30/20m. -
Centre fed half wave dipoles make great, simple and effective antennas for the HF bands. Sometimes however, the centre feed is not ideal. This great project will improve the overall antenna performance. -
The end-fed halfwave antenna is a resonant half wavelength long antenna like a dipole antenna except for it is fed at its end rather then in the center. This antenna is as old as radio and is probably best known as the Zepp Antenna -
Schemaric diagram for a 80m, 40m, 30m, 20m EFHW Antenna Antenna Tuner. The tuner has been designed for an antenna length of 41m and the counterpoise 7.5m. -
A shortened multiband antenna, about 23m long, for 80m - 10m bands with a low SWR (<1.3) on 80m and 40m, and < 3 till 10m. Bandwith on 80m is 300kHz -
A monoband end-fed half wave for 10m, 20m or any other HF band, includes a PDF with detailed information to build your own monoband or multiband antenna -
The article describes the construction of a 1:49 impedance transformer designed to match the high impedance (around 2500Ω) of an end-fed half-wave (EFHW) dipole antenna to the 50Ω impedance of a typical transceiver. The EFHW is a popular portable antenna due to its simple construction, but feeding it can be challenging compared to a center-fed dipole. The transformer was built using an FT240-43 ferrite toroid core, with 2 primary and 14 secondary windings for a 1:49 impedance ratio. A capacitor was added in series with the primary winding to improve performance at higher frequencies. The author compared versions with one and two cores, and found that 100pF worked best for the single core design while 200pF was optimal for the dual core transformer. -
1:49 UNUN using two stacked FT240-43 cores for end fed halfwave antenna. To match the end fed half wave antenna to the coaxial feeder, it is necessary to have a matching network or transmission line transformer. -
An end-fed halfwave antenna for 20 meters band with balun pictures and description by PD7MAA -
A medium power End Fed Half Wave Antenna coupler, specifically tuned to the QRP frequency of 7030 kHz. Constructed from coil stock and capacitors, it achieves an impedance ratio of 64:1. The coupler has proven effective for power ranges from 2 to 100 Watts on the 40m band. -
This article presents a novel Top Loaded End-Fed Half-Wave (TLEFHW) antenna design for 20-meter ham radio operation. The antenna features a compact 14-foot vertical radiator with a capacitance hat configuration, eliminating the need for radials or ground systems. Using EZNEC modeling and field testing, the design achieves a 1.5:1 SWR across the 20m band with a 4.11 dBi gain. Key features include quick deployment, lightweight construction, and directional radiation pattern with 110-degree beamwidth. The design, while requiring a 45-foot footprint due to the top hat, offers an effective portable solution for amateur radio operators seeking a no-ground, no-tuner 20m antenna option. -
A detailed guide by PA2DKW and NQ1R on constructing an End-Fed Half-Wave (EFHW) antenna from an ARRL-partnered HF Kits package. Covers enclosure prep -
A DIY guide for constructing a multiband End-Fed Half-Wave (EFHW) antenna, detailing a transformer-based design for 40m, 20m, and 10m operation. -
The ARRL's End-Fed Half-Wave (EFHW) Antenna Kit is an easy-to-build four-band antenna designed for 10, 15, 20, and 40 meters. Ideal for portable operations, it includes a 49:1 impedance transformer for compatibility with most transceivers. This project, detailed with step-by-step assembly instructions, involves creating a weatherproof enclosure and impedance matching network. The kit simplifies HF operations and supports multiple configurations, making it a versatile tool for amateur radio opertors. -
This page discusses the CLEFHW (Coil Loaded End-Fed Half-Wave) antenna, a portable variation of the popular EFHW design for ham radio operators. The article explains how the CLEFHW allows for backpack portable operation without the need for trees or poles, making it ideal for POTA activations and rapid deployment scenarios. The author details the design, optimization for 20m band, and compares efficiency to full-length wire antennas. Suitable for hams interested in portable antenna solutions and quick setup options for amateur radio activities. -
PH0NO conducted field tests comparing a mobile antenna (DX-UHV) to an end-fed half-wave wire. Results on 20m showed the end-fed wire outperforming the mobile antenna, with a significant difference in signal strength. On 40m, the end-fed wire surpassed the mobile antenna in spots and reach. While the mobile antenna is more practical, the end-fed wire offers superior performance. Further testing is planned. -
This page provides guidance on designing an End-Fed Half-Wave (EFHW) or Random-Length antenna for amateur HF bands, such as 80 or 40 meters. The content explains how to optimize the antenna for multi-band use and match it to a 50-ohm system using an unun. Hams can generate radiation patterns, VSWR charts, and antenna current diagrams for their customized antenna designs. Understanding how antenna dimensions affect performance is essential for successful field operations. The page caters to ham radio operators looking to build efficient and effective HF antennas for their stations. -
Andrew Georgakopoulos, SV1DKD, modeled the End-Fed Half Wave (EFHW) antenna using MMANA-GAL software. He evaluated the EFHW-8010-2K from Myantennas.com for field operations, comparing it to random wires, OCFD, and dipole antennas. His results showed similar performance to OCFD, confirming EFHW's practical feeding advantage but with potential high-voltage risks at the feed point -
Two different ways to create autotransformer for end fed half wave wire antennas, by using ferrite or air core. -
End-Fed Half Wave matching unit project, based on a FT140-43 with SWR plot tests made using capacitor and without. -
An easy to deploy antenna, commonly considered the best solution for portable operations. Thir article includes a simple LC parallel circuit to match the impedance by IW7EHC -
A home made end-fed half-wave antenna coupler with antenna lenght calculator and counterpoise calculator based on center frequency. Includes pictures and drawings along to antenna homebrewing instructions with a home made on air wound transformer -
An interesting article on end fed half-wave wire antennas with a couple of original experiments. Author illustrate the role of the QRP matchbox, and a 40/20 meter antenna with a center stub making it a large bandwidth antenna for 40 and 20. Includes also an 80/40 end fed with the typical coil to make it available on 80 merts band. -
A workign example of a simple half-sized, end fed halfwave for 160 meter band by N0LX -
How to Design and Build a Field Expedient End-Fed Half-Wave Antenna for 20m, 40m and 80m. This Shorty 80m EFHW comprises a 49:1 autotransformer (to match the very high impedance at the end of a half-wave wire), a half-wavelength wire for 40m (also a quarter-wavelength for 80m), a loading coil and a short tail wire. The coil and the short tail wire (about 6 feet) make up the other quarter wave on 80m. -
An end-fed half wave antenna matching unit made of 3:24 turns ratio on a FT140-43 toroid with a 150pF capacitor across the input. -
The author reflects on expanding their antenna for 80m coverage during lockdown. They extend the End Fed Half Wave (EFHW) using a Spiderbeam pole and "cheating" by dog-legging across their garden. Despite challenges, they achieve coverage for multiple bands with minimal cost. Practical Wireless features EFHW antennas, including a pre-made 20m EFHW extended for 40m. -
An home made end fed half wave antenna with a tuner box by NG0R -
This page delves into the debate surrounding the End-Fed Half-Wave (EFHW) antenna, exploring whether it is truly a multiband antenna without the need for a tuner. The author investigates the claims and criticisms surrounding these popular antennas, discussing their resonance on various bands and their efficiency for DXCC achievements. The content is valuable for hams interested in understanding the capabilities of EFHW antennas and their performance across different HF bands, with a focus on practical usage and real-world results. -
KB6NU end-fed, half-wave antenna article and project -
Build a portable End-Fed Half-Wave (EFHW) antenna for 40, 20, 15, and 10m bands with detailed instructions on components and assembly techniques. -
Author experiments end fed half wave antennas using common two conductore speaker wire, this article features a couple of end-fed halfwave wires for the 40M and 20M bands. -
An efficient monoband end-fed half wave for 10m, 20m or any other HF band -
A very well done presentation about End-Fed Half-Wave antennas. This PDF document contains a summary of experiences in how to build custom EFHW antennas. Includes an interesting comparison table of UnUn configurations with recommended toroids, Wire size, turns and capacitors. An useful recap on common errors in building homebrew EFHW Ununs completes the document. -
A trapped multi band end-fed-half-wave antenna for 40/30/20/17/15m. -
An end-fed-half-wave antenna matcher project based on a FT-82-43 core with a 100 pF and 45 pF capacitor in parallel