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The **HFRadioSales.au** resource provides a commercial outlet for amateur and commercial radio operators seeking HF SSB equipment and related services. It focuses on the Australian market, offering new and refurbished transceivers, antennas, tuners, and a wide array of spare parts for brands like Codan, Barrett, and Qmac. The site details its role as a licensed dealer for new Barrett Communications and Codan radio and antenna systems, including specific models such as the Barrett 4050, 2050, and 950, and Codan Envoy and NGT series. This platform supports various applications, including vehicle, 4WD, outback, marine, and base station setups, catering to networks like HF Radio Club, VKS737, and RFDS. It also features commercial-grade antennas from Bushcomm, such as the BBA100C and SWC100, available for fast shipping from their Queensland warehouse. The site includes an FAQ section with general information on mobile HF communications in Australia and timelines for specific transceiver models.

50 MHZ Moxon antenna based on the KG4JJH design with some slight modifications in the construction

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.

A mobile vertical antenna for 40 meters band by W4NFR

Antan is a homemade antenna analyzer project by F6BQU

Quad and loop antennas comparisons, evaluating the impedance and gain of both antennas and considerationso n horizontal loop antennas for low bands by PA0FRI

Demonstrates the design and construction of a compact, portable multi-band mini-delta loop antenna, specifically optimized for /P (portable) operations from remote locations like Scottish islands. The resource covers the theoretical underpinnings of half-wave loops, contrasting closed and open configurations, and then details the application of a folded dipole principle to achieve a 50-ohm match for direct coax feed. It presents empirical formulas for calculating element lengths, considering the velocity factor of common wire types, and provides a detailed example for a 20m (14.175 MHz) version. The article includes a comprehensive table of dimensions and allowances for a five-band (20m, 17m, 15m, 12m, 10m) mini-delta beam, along with construction hints for the central support and balun. It specifies a 1:1 trifilar balun wound on a ferrite rod and describes the antenna adjustment process using an _MFJ-259B Antenna Analyser_. Initial test results indicate an SWR of 1:1 at resonance and a bandwidth of approximately 240 kHz on 20m, even at a low height of five feet above ground. The distinctive utility lies in its focus on a practical, easily deployable beam antenna for portable DXing, offering a viable alternative to more complex or larger arrays.

Article on mobile ham radio antenna setup

Based on original G2BCX design this J-Pole antenna for the six meter band is made with a homemade ribbon cable. The antenna shown in this article includes a coaxial cable choke feed to remove RF currents from flowing on the outer of the cable.

Screwdriver Antennas by Ron Wilson

AA5TB homemade balun article

Small & practical DIY inverted U antenna. This design worked very well during the 2017 CQWW 160M SSB contest.

A Quagi antenna project with pictures and dimensions for a UHF Quagi antenna

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

Demonstrates the construction and measurement of a single-turn HF receiving loop antenna, built from common materials like electrical conduit and lamp cord. The resource details the physical dimensions, including a 4-meter circumference, and calculates the theoretical inductance at approximately _6.4 uH_. It outlines a method for determining resonant frequencies across the 4-17 MHz range using a _C Jig_ and a _VR-500 receiver_, coupling the loop with a ferrite ring. The article also discusses the impact of receiver coupling on the loop's Q factor, noting a degradation in sharpness due to the transformer's reflected impedance. Analyzes the observed resonant frequency patterns, highlighting an unexpected rise in the loop's effective inductance at higher frequencies, particularly above 13 MHz. While some increase is attributed to distributed capacitance, the rate of rise suggests further investigation. The experimental setup provides practical insights into the challenges of maintaining high Q in simple receiving loops and offers a comparative reference for other homebrew antenna projects, such as those by _VK2TPM_.

A simple TRAP-dipole project for 20 and 40m bands includes EZNec simulations

A discone antenna plan and pictures with renderings designe mainly for RTLSDR usage

A triband VHF Yagi antenna for 6 m, 4 m and 2 m with one feed-point by DK7ZB

A shortened 20m vertical antenna design made with 4Nec2

Electronically controlled HF antennas. General coverage. Top features on all ham bands. Very advanced materials and state of the art technology.

Christoph petermann's df9cy six element yagi antenna for six meter band

Halo antenna plan for the six meters band

The rhombic antenna is a diamond-shaped antenna, suspended between 4 masts.

A 100Ft wire antenna for the top meter band

One of the most useful antennas in the repertoire is the Marconi or quarter wave grounded vertical antenna. Its invention made it possible to halve the length of antennas, simplifying communications, especially at HF and below.

A simple antenna tuner for 4m by Tony Hawker G4CJZ

DK7ZB- Moxons with Aluminium Tubes, plans for moxon antenna for 6 10 12 15 meters

A dipole for 2m, 4m, 6m band an hamdwritten note for a homemade vhf antenna that can be tuned across the VHF 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.

Making your own 2 metre (146 MHz) 5/8th wave whip antenna

The Skeleton Slot Antenna Revisited by Bobby Brainwave, N3VGS PDF File.

A magnetic loop antenna using a 28\" bicycle rim for six meter band

Realization of the YU7EF 6m(6elm) and 4m(7elm) duo band antenna on a 6m boom by OZ1DJJ

A trifilar folded dipole antenna for 80 meters band

A vertical antenna that can cover HF bands using an UN UN and a fishing pole, usage of tuner is requested.

Near Vertical Incidence Skywave (NVIS) and the 40 meter Novice Sub-band.

W4KAZ article on antenna switches

The industry standard in all antenna products

Demonstrates the design principles and performance characteristics of **corner reflector antennas**, emphasizing their high gain and directional properties. It covers critical design factors such as the corner angle and the spacing between the radiating dipole and the reflector vertex. The resource explains how reducing the corner angle increases gain but lowers feed impedance, making matching more challenging. Practical angles of 90 degrees or 60 degrees are discussed, with 90 degrees offering easier impedance matching despite slightly lower gain. Details key design considerations, including reflector side length exceeding two wavelengths and reflector width greater than one wavelength for a half-wave radiator. It specifies reflector construction using wire netting, sheet metal, or parallel metal spines spaced less than 0.1 wavelength. The article provides a table with general dimensions for UHF and VHF bands, noting typical impedance values of 50 to 75 ohms and expected SWR of 1.7:1 on the lower band edge. Adjustable radiator-to-vertex spacing is highlighted as crucial for final tuning.

Calculate EH Antenna, 20m 40 80m. Fotos, Original eh antenna building.

N6RK receive 4 square antenna with transformer coupled antennas and true hibrid combiner

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

A moxon anetenna plan for 144 MHz

A dual band wire antenna project in Italian

Presents a commercial entity specializing in robust portable antenna mounting solutions for amateur radio field operations. The company's primary offering, the Tilt-N-Raise system, facilitates rapid deployment and secure elevation of various HF and VHF/UHF antennas in temporary setups. These mounts are engineered to withstand environmental stressors commonly encountered during DXpeditions, contests, and emergency communications exercises. The design emphasizes ease of assembly and transport, crucial for operators frequently deploying antennas away from fixed stations. The system typically accommodates mast sections, allowing for significant antenna height, and provides a stable base for directional arrays or wire antennas. Operators utilize such mounts to optimize signal propagation and minimize setup time in diverse outdoor environments.

DIY a sector antenna for de Wifi 2,4GHz ISM band.

How to build the Quickie Pneumatic Antenna Launcher

An interesting home made project of an L Network Antenna Tuner Project with pictures and schematics by K7SFN

Basic information on the folded dipole antenna