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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.

10GHz Rainscatter audio files

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

The Voice of America (VOA) website serves as a primary digital platform for its international news and information services, broadcasting in 44 languages. The resource presents a wide array of current events, geopolitical analyses, and cultural reports, reflecting a global perspective on news originating from the United States. Content spans various regions, including Africa, Asia, the Middle East, and specific country-focused reports from VOA's language services, such as VOA Uzbek, VOA Kurdish, and VOA Russian. The site features top stories, special reports, and sections like "All About America" and "VOA Explains," providing in-depth context on US-related topics and global issues. The VOA platform offers a continuous stream of updated news articles, covering political developments like government shutdowns, diplomatic relations, and international conflicts, alongside social and economic issues. It also includes sections for "Worth Watching" videos and "From VOA's Language Services," highlighting the breadth of its multimedia output. The content is designed to inform a worldwide audience, often presenting multiple perspectives on complex international events and US foreign policy, making it a significant reference for those monitoring global news and shortwave broadcast content.

Presents a dynamic, searchable database of shortwave broadcast schedules from around the world, enabling users to locate active stations or plan listening sessions based on scheduled transmission periods and frequencies. The resource details specific station names, such as _Radio Habana Cuba_, _Deutsche Welle_, and _All India Radio_, alongside their operational times and assigned kilohertz frequencies. It also incorporates a distance calculator, which leverages geographical coordinates to estimate propagation paths, though it notes occasional data inaccuracies leading to transmitters appearing in oceanic locations. The platform's development log highlights continuous updates, including the integration of new seasonal schedules like "A24 frequencies" and "B23 schedule," reflecting the fluid nature of shortwave broadcasting. It documents challenges with geolocation services, particularly concerning Google API changes that impacted distance calculations and required user-side browser configuration adjustments for optimal functionality. The site owner, VAXXi, frequently communicates these technical adjustments and database updates, often acknowledging user contributions and donations. Distinctively, the resource provides a historical perspective through its update archives, illustrating the evolution of shortwave listening over more than a decade since its inception in 2011. It also mentions specific events, such as the BBC adding shortwave broadcasts for Ukraine on 5875 kHz and 15735 kHz, demonstrating its responsiveness to global events impacting broadcast schedules. The site's commitment to user feedback is evident in its bug reporting and feature request mechanisms, contributing to its ongoing refinement.

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.

Shortwave Radio Schedules from Eibi/AOKI combined lists. Includes Google maps showing beam directions and long paths.

A ground plane antenna for 80 meters band

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

Address and links of many broadcasting stations

Article using a full wave delta loop antenna at low height, feeding methods, performance reports on 1984 QST article by W1FB and W1SE

This article document a 2 element half wave collinear J-Pole antenna by KC9EOT and KB8OJH

Useful pages of longwave operations, includes a lot of reference files, beacons list, sounds and pictures

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.

How to make a half l or quarter l coax cable for a specific frequency

Basic of shortwave antennas

a methodology for connecting multiple LF/MF/HF receivers to a single antenna via readily available and inexpensive 75-ohm TV cable.

Demonstrates the construction of a _3MA triband mobile antenna_ designed by IZ7DJR, emphasizing a full-size quarter-wave whip for 10 meters. The design incorporates a rapid tilt-down mechanism to facilitate quick changes of loading coils for operation on 15 and 20 meters. This approach aims to minimize losses and enhance efficiency compared to conventional base-loaded mobile antennas. The resource provides specific coil winding data: 22 turns for 15 meters and **37 turns** for 20 meters, both using 1mm wire over an 80mm coil length. The 10-meter band operates without a loading coil, leveraging its full-size design. The author's design prioritizes ease of band switching and improved performance for mobile HF operations, offering a practical alternative to more lossy commercial options.

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

Shortwave frequency list and swl links

Provider of point-to-point microwave radio system sales, service, and integration, employing refurbished name brand digital (DS1/E1, DS3/E3) and analog video radios. Specializing in Microwave Associates (M/A-COM) , Digital Microwave Corp. (DMC/Stratex) and Alcatel/Rockwell microwave radios.

A blog with loggings and information relating to shortwave pirate radio in Europe.

Shortwave Monitoring Station in Berlin: DX news, HF propagation, greyline, DRM news, QSL gallery, audio recordings and more

Cobalt Pet is a weblog focusing on shortwave radio. It features shortwave reception reports, product reviews, photos, listening tips, and links. International broadcasters and amateur / ham radio operators are monitored and discussed.

A guide on writing reports to broadcasting stations and obtaining QSL cards

All antennas that are situated close to the ground are affected by that ground to some extent. This article explain effects and benefits of counterpoise.

Presents a curated collection of newsletters dedicated to _Earth-Moon-Earth_ (EME) communications, primarily focusing on the 432 MHz band and higher microwave frequencies. The resource details various EME DX experiences and news contributions from operators like K2UYH (W6/PA0ZN), offering insights into successful moonbounce contacts and operational strategies. It serves as an archive of specialized content for those engaged in or interested in extreme weak-signal propagation via the moon. The newsletters provide practical information on achieving EME contacts, often including details on station setups, antenna arrays, and signal reports from challenging DX. For instance, operators might report achieving contacts over **750,000 km** round trip, demonstrating the feasibility of long-distance communication on UHF and microwave bands. The content differentiates itself by concentrating on the unique technical and operational aspects of EME, which contrasts significantly with terrestrial DXing, providing a specialized knowledge base for advanced amateur radio operators.

Exploring ULF-ELF and VLF radio band

A practical approach to microwave signal analysis for the home experimenter

Pirate radio recordings, addresses, links and QSLs

Kurzwelle, shortwave, Radio , DX, broadcasting, QRG, SWL, receiver, Empfnger, BCDX, DX-Clubs, hobby, QSL, schedules, Frequenzen

A workign example of a simple half-sized, end fed halfwave for 160 meter band by N0LX

A ferrite antenna for Low Freqencies

The Icom PCR1000 review by GW0KIG

What is an EWE Antenna, comparisons, performance and homebrew plan

Repair and sales of refurbished, point-to-point, digital microwave radios manufactured by Alcatel and Digital Microwave Corporation (DMC).

This page allows you to calculate in the most accurate way high-Q inductor coils.

Showcasing a specialized product line, Advanced Receiver Research presents a comprehensive catalog of **low noise preamplifiers** and microwave **Gunnplexers**. The offerings span a broad spectrum of radio frequencies, from VLF, LF, MF, and HF bands up through VHF, UHF, and microwave, catering to diverse applications including amateur radio, commercial installations, and military systems. Their product range includes mast-mount preamplifiers, inline attenuators, power dividers, and various coaxial components. My own experience with similar low-noise front ends for weak-signal work on 2 meters and 70 centimeters underscores the critical role such components play in maximizing receiver sensitivity, especially when chasing distant DX or engaging in EME. The detailed product descriptions and technical specifications provided on the site allow operators to select the optimal preamplifier for their specific band and noise figure requirements, essential for improving signal-to-noise ratio. The site also lists specialized products for unique applications like Nuclear Magnetic Resonance (NMR) and Studio Transmitter Links (STL), demonstrating a depth of engineering capability beyond typical amateur radio fare. This breadth of offerings, coupled with clear ordering and warranty information, positions Advanced Receiver Research as a key supplier for high-performance RF components.

Measurements for building a full wave loop using wire

Microwaves articles, The Technology Voice of the Wireless World , need registration to access

An efficient monoband end-fed half wave for 10m, 20m or any other HF band

End fed half wave tuner a handy tool for field day and portable operations

This article contains the measurements for building a full wave loop using wire and length of 1/4 Wave Coax Matching Transformer

"The DSWCI was founded 1956 and has members in 36 countries all over the world. The member bulletin ""Shortwavenews"" is published regularly in english."

Exaustive shortwave dx and tech resources for BCLs.

6 Meter 1/4 Wave Antenna by Mike Fedler N6TWW. A detailed article with pictures of construction details of this 50 Mhz antenna

A 50-ohm generator feeding a 50-ohm line connected to a _quarter-wave transformer_ (150 ohms) terminated in a 450-ohm load is analyzed to understand transient behavior. The paper meticulously tracks voltage and current waves, reflection coefficients, and power levels through a sequence of events, starting from quiescent conditions. It details how incident and reflected waves combine and interact at impedance discontinuities, illustrating the dynamic changes in impedance and SWR at various points in the system. The analysis reveals that the impedance at the interface between the 50-ohm line and the 150-ohm transformer changes from 150 ohms to **64.3 ohms** after the first reflected wave arrives. Subsequent reflections cause the impedance to asymptotically approach 50 ohms, reaching **53.22 ohms** after five wave terms. The study also examines the generator's reaction to transient SWR changes, noting that a 3:1 SWR can temporarily reduce generator output to 0.75 watts, but these effects are temporary and diminish as the system approaches steady-state conditions.

Founded in 1946 in the UK, the ISWL is Global. We cater for Licensed Amateurs and all types of Shortwave Listeners. Offer a comprehensive awards programme and run a very efficient QSL Bureau.

Use this online calculator to determine the length of a quarter-wave antenna from the frequency. Both metric and English units of measurement are supported.

Use this online calculator to determine the length of a full-wave loop antenna from the frequency. Both metric and English units of measurement are supported. Quarter-wave matching section lengths are also calculated.