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US amateur radio antenna manufacturer. Produce baluns, delta loops, dipoles, ocf antennas and more

KB6NU end-fed, half-wave antenna article and project

Investigates the legal framework surrounding **pneumatic antenna launchers** in Victoria, Australia, specifically their classification under the Firearms Act 1996. The author, VK3KBC, details how these devices, designed to discharge a projectile by compressed air, are defined as 'firearms' and subsequently categorized as **Category E Longarms**. This classification carries significant penalties for unregistered possession or use, with the author noting the lack of provisions for amateur radio operators to legally possess and use such devices for antenna deployment. The author shares personal experiences needing such devices for portable HF radio operations, contrasting them with previously legal slingshots and current alternatives like kites or bow and arrow. VK3KBC outlines efforts to advocate for legislative change, including submissions to the Wireless Institute of Australia (WIA) and the Victorian Department of Justice, proposing an amendment to Section 3(i) of the Firearms Act 1996 to include amateur radio field operations as an exempted use. The resource also reviews the original intent of the Category E firearm classification, suggesting that pneumatic antenna launchers may have been assigned this category in the absence of a more suitable alternative.

How to make proper maintenance of your antenna. Fighting Antenna Corrosion is a QST article published in 1993 that helps on antenna maintenance works

The 160-meter amateur radio band, spanning 1.8 to 2 MHz, was historically the lowest frequency amateur allocation until the introduction of the 630-meter and 2200-meter bands. ITU Region 1 allocates 1.81–2 MHz, while other regions use 1.8–2 MHz. This band, often called "Top Band" or "Gentleman's Band," was established by the International Radiotelegraph Conference in Washington, D.C., on October 4, 1927, with an initial allocation of 1.715–2 MHz. Effective operation on 160 meters presents significant challenges due to the large antenna sizes required; a quarter-wavelength monopole is over 130 feet, and horizontal dipoles need similar heights. Propagation is typically local during the day, but long-distance contacts are common at night, especially around sunrise and sunset, and during solar minimums. The band experienced a resurgence after the LORAN-A system was phased out in North America in December 1980, leading to the removal of power restrictions.

A Simple Delta Loop Antenna for Smaller Vessels

A shielded broadband (~200 MHz) active loop antenna offers more quiet and relatively less interference reception.

Constructing a compact directional antenna for the 17-meter band, this resource details the build process for a Moxon rectangle, a two-element Yagi variant with folded-back elements. It covers the antenna's evolution from the _VK2ABQ beam_ and provides specific dimensions for a version built using fishing pole whips. The content includes a discussion of the antenna's radiation pattern, feedpoint impedance, and its inherent front-to-back ratio, which is often superior to a standard two-element Yagi. Practical considerations for element spacing and material choices are also addressed, alongside a visual representation of the antenna's physical layout. Performance data presented includes a comparison showing the Moxon rectangle's **2.5 dB gain** over a half-wave dipole and a front-to-back ratio of **20 dB**. The resource also touches upon the antenna's relatively wide bandwidth for a two-element beam and its suitability for portable operations due to its compact footprint. It offers insights into optimizing the design for specific operating conditions and discusses the advantages of its lower take-off angle compared to omnidirectional wire antennas, making it effective for DX contacts on the 17-meter band.

How do we make an HF station work more effectively? Antennas are the key!

A study on 20m antennas by Kenny Silverman, K2KW

The Superantennas MP-1 portable HF antenna is analyzed for its design and field performance, particularly its high-Q loading coil and 3/8-inch mounting. The review details the antenna's construction, including an 8-inch vertical section, a large-diameter loading coil tuned by a sleeve, and a 4-foot whip that disassembles into six rods for transport. Initial testing with the supplied 10-foot ribbon cable "ground plane" yielded poor SWR and RF hot conditions, indicating an inadequate ground system. Further experimentation with longer radials and resonant counterpoises for each band improved matching and eliminated RF hot issues, but introduced significant operational complexity. The author notes the difficulty in optimizing both counterpoise length and coil setting without an antenna analyzer, and the sensitivity of the MP-1 to counterpoise deployment. The review also discusses the recommendation to tune for maximum received signals rather than minimum SWR, often necessitating an external ATU due to the antenna's typical low impedance. The **MP-1**'s critical dependence on resonant counterpoises for effective operation, especially when elevated, is highlighted as a major drawback for portable use. The author ultimately sold the antenna, concluding that despite its sound technical design, its fussy nature and the need for extensive counterpoise management or an ATU detract from its portability and convenience compared to simpler, less expensive dipole solutions. The **Superantennas MP-1** is deemed a flawed portable antenna, requiring considerable effort to achieve its claimed performance.

This article deal with various means to covertly operate radio systems while going unobserved.

A 70cm ground plane antenna made with a 90cm of 1mm silver steel rod

A considerably shortened Magnetic Loop antenna with performance of a single conductor text book magnetic loop.

Horn Antennas theory and principles

Antennas are influenced by the effect of the ground and by the type of conductors from which they are constructed. Effects of various types of grounds on a 1.825 MHz horizontal 0.5 wave dipole

T2FD is a 600-900 ohms folded dipole, terminated with resistor. Feed impedance is coupled with 50/600 ohms voltage balun. It is a wide band antenna with rather low SWR over the full designed frequency range: antenna tuner is seldom needed.

An easy to build and extremely high performance antenna, works perfectly on all HF bands 3.5-28 MHz with some compromises, it is basically an half wave dipole for 40-80 meters, an LC circuit or trap 40 meters allows you to use a single radiating element.

How to build Fan-Dipoles by DK7ZB. Experiences with various band combinations. Not all combinations are working properly. If the frequencies are to close together the impedances will lead to a very bad SWR. This happens with the bands 10-12-15m or 15-17-20m.

Comment on W5DXP 2011 coil measurement experiment

Converting a little Radio Shack CB mobile magnet mount antenna to a VHF ham radio antenna

A review of all possible receiving antennas for top band 160 meters

Some notes on double-shielded coaxial cable

A project for a ground mounted 4 square antenna by DM9EE

A different implementation of the G7FEK HF multiband antenna with some adjustments and modifications

How manage and quantify ground loss in vertically-polarized antennas by VE3VN

Homebrewing portable antennas for field day operations

N5KGL interesting article on portable antennas. Greg report his experience on using several types of portable antennas.

Ultra portable and lightweight folding beam antennas based on G3TXQ design

WA1ION article on beverage and ewe antennas

A helically wound vertical antenna experiment. 14 meter of wire wounded on a 8 meter fishing pole with 4 elevated radials

A simple, cheap and easy to build 26 feet long vertical antenna that works DX on 20 - 10 meters including WARC Bands, it is designed for portability for field days, camping, or permanent installation, cost, and to achieve at least 1/2 wavelength on the WARC bands.

HF VHF UHF antenna ideas to be used for field days. All antennas are quick to set up and take down and offer proven performance and flexibility. Presentation offered by Mahoning Country ARES

In this article you can find solutions to the problem of keeping your ham radio antennas hidden from the CCR Police

Essentially, a choke balun is designed to 'divorce' your antenna from the feed line. if your feed line is coaxial cable then you don't want it to be part of your antenna. you want to be able to deliver all your power to the radiator itself, i.e. 'the antenna'. a choke balun does this admirably

The ZR6YY Antenna for 6m by Maurius ZR6YY revisited by YT1VP

G0KYA MMANA-GAL presentation and samples

A Microvert antenna by KD5RVX based on the original microvert concept by DL7PE. PDF includes a 20 foot portable PVC tower project

W3HH wide-band wire antenna Article in French. The W3HH antenna, also known as the Terminated Folded Dipole (T2FD), is a compact, broadband antenna for amateur radio. It operates at an angle of 20 to 40 degrees and covers frequencies from 3 to 30 MHz. The antenna features a total length of one-third of the wavelength at its lowest frequency and is fed using a 1:4 BALUN transformer for impedance matching. A termination resistor around 390 Ω optimizes performance, making it suitable for various amateur radio applications while being easy to construct and install.

Design for a quarter wave vertical antenna, for the top band in use at V31YN

SPIDERBEAM.US is the exclusive distributor of Spiderbeam antennas, and online shop for USA & CANADA

This article is about a 4 element yagi VHF antenna designed to be easy to be assembled and suited for portable operations

Design a 50MHz long-yagi antenna by PA3FGA

Understanding Amateur Radio NVIS Antennas and Propagation

NRSC AM bandwidth measurements with the loop antenna

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.

A 7 dB directional gain is reported for this portable VHF Yagi antenna design, which utilizes cut metal tape measure sections for its elements. The resource details the construction process for a 2-meter band antenna, emphasizing its ease of build and portability. It specifically mentions the design's suitability for radio direction finding (RDF), fox hunting, and communication with satellites and the International Space Station (ISS), highlighting its practical applications for amateur radio operators. The construction cost is estimated at under $20, with potential for even lower expense if salvaged materials like old tape measures and PVC pipes are used. The article references _Joe Leggio's_ (WB2HOL) original design, noting specific alterations made by the author. It also compares this design to other DIY Yagi antennas, including _FN64's_ 2-meter band and _manuka's_ 70-cm band tape measure Yagis, underscoring its unique combination of simplicity, portability, and effective performance with a 1:1 SWR achievable on the 2-meter band.

A moxon antenna for the 50 MHz build with 19 feet of 14 AWG copper wire, and based on a set of PVC pipes. This is an easy to build project that will give you an efficient directional antenna on 6 meters band with low SWR on more than 1 MHz bandwidth.

4 Square K9AY Array project for 80 and 40 meters band

Article about an end-fed anntenna for the 17 and 12 WARC Bands. 30 meters is not included in this project. This antenna includes a 14 windings unun impedance transformer using a FT-140-43 ferrite toroid, that should be enought for a 100W PEP.