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UHF 3 element portable antenna with gamma match by ON6MU

The ZS6BKW multiband HF antenna, a design by ZS6BKW (G0GSF), functions effectively on multiple HF bands without requiring an Antenna Tuning Unit (ATU) for 40, 20, 17, 12, 10, and 6 meters. This antenna, approximately **27.51 meters** (90 feet) long with a 12.2-meter (40-foot) open-wire feeder, is a direct descendant of the _G5RV_ but offers superior multi-band resonance. It can be deployed as a horizontal dipole or an inverted-vee, with the latter requiring only a single support and maintaining an apex angle of at least 90 degrees to prevent signal cancellation. Performance data, recorded with an MFJ Antenna Analyser, indicates SWR values of 1:1 on 7.00 MHz (40m) and 14.06 MHz (20m), with SWR below 1.3:1 on 17m, 10m, and 6m. While primarily designed for these bands, the antenna can be adapted for 80m, 30m, and 15m with an ATU, preferably at the balanced feeder's base. The use of 450-ohm twin-lead for the feeder is recommended over 300-ohm for improved strength and reduced losses, especially in adverse weather conditions. This design, originally published in _RadCom_ in 1993 and featured in Pat Hawker’s "Antenna Topics," provides a compact and efficient solution for HF operation, particularly for those with limited space or resources.

The G3TPW Cobwebb antenna covers five bands, 14 - 28 mhz, including the WARC bands

Freeware antenna software that lets you see what the polar diagram of your rotatable beam actually looks like where it is operating. With PolarPlot you can measure the polar diagram of the antenna and check for abnormalities - compare plots taken before and after changes to the design or location - check the -3dB beamwidth - look at the front to back ratio - see the size and position of the sidelobes.

The Adcock antenna has been used for a long time for RDF. It is basically an interferometer.

Using delta match with HF antennas design

Download the PDF with USA Amateur radio HF band plan and common country prefixes updated in 2008 by Icom

A project by DL5DBM for a VHF UHF antenna suitable for handheld transceivers

Infomration schematics and pictures about various hf and vhf QRO linear amplifiers

A rotary trapped-dipole for 17 and 20 meters, as described by IZ7ATH, presents a practical solution for multi-band HF operation. The author, Talino, recounts his experience building this antenna for IK7ZCQ, detailing the evolution from an initial concept involving a grounded-driven element and gamma-match to a direct-fed, non-grounded design. His pragmatic approach, adapting available materials, is evident throughout the construction narrative, particularly with the use of eight tapered aluminum pipes for the driven element. Construction specifics include precise measurements for the aluminum tubing, with diameters ranging from 30 mm down to 16 mm, and a critical note on reducing tip thickness for weight optimization. The _traps_, initially a concern, are fabricated using 8 turns of RG58 coax on a 27 mm support, tuned to resonate at 18.1 MHz using a dip-meter. Talino emphasizes sealing the traps with RF glue and PVC tape to prevent water ingress, a crucial step for longevity. Field test results, conducted on a 10-meter pole in a clear garden environment, showed an SWR of 1.2:1 on 17 meters and 1.5:1 at 14.200 MHz. While SWR varied slightly when installed at Mario's QTH due to nearby objects, the antenna's performance remained commendable. The final half-dipole length is 46 cm for the 18 MHz tips, and the total weight is under 6 kg, with potential for further reduction.

HF/6M antenna tuner preselector and antenna switcher project by ON6MU

US ham radio band plan in pdf available for download and print

AM/FM/CW QRP RF Power Amplifier for the HF 10 or 11 meterband (28MHz/27MHz)

Tarheel Antennas presents its product line of motorized **screwdriver antennas** and stainless steel mounting solutions, engineered for both amateur radio operators and commercial users. The resource details the manufacturing process, emphasizing in-house CNC machining and the use of quality materials for durability and performance. It highlights the company's commitment to U.S.-based manufacturing, with products built in St. Joseph, MO, since 2008. The site provides essential contact information for sales and technical support, including email addresses and phone numbers. It also includes a mailing address for physical correspondence. While noting a temporary absence from the Dayton Hamvention in 2024, the company expresses intent to return in 2026, indicating engagement with the amateur radio community.

English language International Shortwave broadcasts listed by search time.

1500 Watt HF power amplifier

If you have ever tried transmitting on HF from a tall block of apartments, where it's just not possible to erect a substantial aerial system, then this article is for you

Italian page including pictures schematics diagrams of an home made linear amplifier using four EL509 in parallel. Output power is about 700W.

These pages provide general propagation advice for HF communicators. Information available includes inferred global propagation conditions, real time HF fadeout coverage charts, regional ionospheric vertical MUF maps and Hourly Area Prediction charts for Astralia and Asia, Europe and North America

A pedestrian antenna is considered to be a lightweight antenna that can easily be carried to the shootout by one person in a backpack or bag.

This project is about a cheap way of building a colinear antenna for VHF 145MHz, and having about 10dB more gain than that little 1/4-wave magmount

Constructing a high-power solid-state amplifier for HF operations presents unique challenges, particularly when aiming for significant output like 600 watts. This project details an amplifier design employing **Motorola MRF150** FETs, a common choice for their robust performance in RF power applications. The design emphasizes achieving substantial power output, a critical factor for effective DXing and contesting, where every decibel can make a difference in signal propagation and readability. While specific circuit diagrams or construction details are not directly presented on the current page, the mention of MRF150 FETs points towards a design that would typically involve push-pull configurations, impedance matching networks, and robust power supply considerations to handle the high current demands. Such amplifiers are often built with an eye towards linearity and efficiency across the HF bands. Amateurs pursuing similar high-power solid-state projects often share insights on thermal management, intermodulation distortion, and component sourcing, all vital for a stable and reliable amplifier capable of delivering 600 watts into a proper antenna system.

NuMorse 2.20.0.0 for Win 7/Win 8/XP/Vista/Win 10 A complete rewrite of the original NuMorse used by thousands of radio amateurs to gain and upgrade their licenses. NuMorse offers an intermediate feature set that is somewhere between the lean and mean NuCode program and the vast array of features supported by NuMorse Professional. But NuMorse is no cut-down program. It has several unique features not found in other Nu-Ware products as well as a compact and intuitive set of controls that you will be able to learn quickly.Product is no more developed and out of support.

KF4SCI picture of a project for a VHF UHF jpole antenna working on 220 and 440 MHz.

W5ALT Indoor Vertical Antenna is a base loaded vertical antenna that can be tuned on almost all HF bands by adjusting a big coil. Operating a ham radio station from an apartment in Maracaibo, Venezuela, the author demonstrates effective communication with over 100 countries using a custom-built indoor vertical antenna. Addressing common misconceptions, the design uses a balanced approach with radials and a base-loaded vertical element made from affordable materials. The antenna fits discreetly indoors, covers 6 to 40 meter bands, and achieves acceptable SWR with an MFJ tuner. Despite limited space and typical apartment challenges, the setup enables reliable DX contacts, confirmed by numerous QSL cards, proving indoor antennas can perform well in constrained environments.

HF QRP Linear Amplifier with 2x 2SC2166 + 2x 2SC1969 Push Pull Transistors (13.8V)

A vhf moxon antenna plan

The Elecraft K3, a popular HF transceiver, is often benchmarked against new market entrants. This article critically compares the Kenwood TS-590S to the K3, focusing on key technical specifications and operational aspects relevant to serious amateur radio operators. The author proposes three distinct evaluation methods: a circuit diagram comparison, an independent review analysis (referencing Peter Hart, G3SJX, in RadCom), and a real-world "ear test" by experienced contest operators on 40 and 80 meters. The analysis delves into specific receiver components, including the first mixer design, RF and IF amplifier performance, and the presence of an image noise filter. It highlights the K3's switched mixer and the potential for the TS-590S to utilize similar or improved designs, such as a classic filter with enhanced selectivity. The article also scrutinizes the second mixer stage, noting the K3's SA612 chip and its associated IP3 limitations, suggesting Kenwood might achieve benefits with a different mixer architecture. Further points of comparison include DSP capabilities, where the K3's high-performing DSP with KK7P's involvement is noted against the TS-590S's potential reliance on newer IC technology but possibly less refined software. The discussion extends to DDS and PLL implementations for phase noise and spurious emissions, and the utility of a second receiver for DX chasing and contesting, acknowledging its importance for some operators while being less critical for others. The article concludes by emphasizing personal preference in equipment selection.

Do your multiple-transmitter field day or contest efforts suffer from intrastation interference ?

VHF Antenna in a lunchbox. The magnetic loop on two metres band Lloyd Butler VK5BR

Yaesu FT 101 unofficial web site managed by NW2M

Memory management (cloning) software for the Yaesu FT-8900R quad band FM mobile transceiver

10 to 20 meters band log-periodic antenna project with SWR Plots, boom lenght and element spacing.

Memory management programming software for the Yaesu VR-5000 receiver

An air cored 1:1 balun for 3.5 to 30.0 MHz

Amateur Radio bandplan in a large PDF A3 format valid for Serbia and Region 2. This band plan can be donwloaded and printed on a color laser printer for optimal quality.

A homemade Magnetic Loop antenna from a spare 3m length of RG213 working from 30m to 15m with a 130pF tuning capacitor

A simple and low cost multiband vertical hf antenna covering 5 bands (20m-10m) from an old CB antenna

A large worldwide map of aeronautical service Frequencies allocation on HF bands dated 2002

Gi7b is tube designed for microwaves but working good as HF amplifier. Idea is to build cheap, reliable HF amplifier covering 160 meters band.

This is a base-loaded vertical antenna that mounts on the car's roof. The loading coil is designed as a variable inductor, with a three-legged chariot that travels up and down inside the coil, with grooved brass wheels running on the coil turns, and driven by a slotted rotor tube.

G3YCC article pn the W3EDP end-fed antenna for 80 to 20 meters bands

A standard 6 elements design scaled for UHF application. All material used in this project are easily obtainable tubes and rods which is limited within a total budget of $18.

Reccomendations and tips for VHF-UHF operation

Elelement yagi beam antenna for 2 meters band by ON6MU

How to build a high gain vertical antenna for the UHF amateur or CB Bands, by radio experimenters handbook

Looking for Hams that want to experiment on VHF/UHF PSK/digital modes

A multiband end-fed antenna that cover 3.5 to 30 Mhz using a 1:64 Balun based on a FT240-43 core

Features and specifications for discontinued yaesu ft-100d radio

3 to 30 Mhz antenna analyzer schematic by YO3DAC / VA3IUL