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The Maria Maluca HF multiband antenna as designed in 1957 by PY2BBP is a directive antenna for 15 meter and a passive element that works as director and reflector in different bands

An experimental prototype of an asymmetrical hatted vertical dipole antenna that can work on HF bands 20 to 10 meters band. The AHVD Vertical dipole is an upside-down T design

Article on propagation basics. The ground wave used for radio communications signal propagation on the long, and medium wave bands for local radio communications

The purpose of this article is to provide radio amateurs with enough background information to understand the technical challenges involved in small-station digital EME on the 144 and 432 MHz bands.

HamGear.eu page about the FT-100, 160 to 6 meter bands plus the 144 MHz and 430 MHz bands transceiver from Yaesu.

The Barrow Amateur Radio Emergency Service Club (BARES) serves as a local hub for amateur radio operators in Barrow County, Georgia, focusing on community engagement and emergency preparedness. Established in 2007, the club provides a platform for hams to connect, share knowledge, and participate in various radio activities. Members often engage in public service events, offering communications support, and conduct regular meetings to discuss technical topics and operational procedures. BARES emphasizes the importance of emergency communications, with members frequently training for and participating in simulated emergency tests (SETs) and real-world disaster response scenarios. The club maintains a focus on local area coverage, ensuring reliable communication infrastructure is available when traditional systems fail. Their activities often involve operating on _VHF_ and _UHF_ bands for local nets and _HF_ for longer-distance emergency coordination. Key activities include field day operations, technical workshops, and supporting local events with radio communications.

Before the advent of digital transmission modes, several analog schemes were developed to transmit images or image-like information on the Amateur Radio bands.

Signal marker for the microwave bands

Summit Prowler 6 is a pocket-sized SSB/CW transceiver for 80, 40, 30 and 20m

This project details the construction and testing of a M0PLK Delta Loop antenna for the 20-10m ham radio bands. Inspired by positive reviews highlighting its reduced local QRM compared to Cobweb antennas, the author built the antenna using aluminum tubes, DX-Wire FS2 wire, and a 1:4 balun. A mix of custom 3D-printed parts and careful assembly ensured stability and performance. Initial VSWR measurements met expectations, and test QSOs demonstrated success across multiple bands. Future enhancements include adding a lightweight, remote-controlled rotator for directional capabilities.

Presents the full owner's manual for the _Drake R-4C_ communications receiver, specifically a late version edition. This resource outlines the comprehensive operational instructions, covering everything from initial setup and tuning to advanced features and controls. Hams can reference detailed diagrams and explanations for proper signal reception across various amateur bands. The manual includes critical information for alignment procedures, ensuring the receiver performs to its optimal specifications. It details the steps required for calibrating the internal circuitry, which is essential for maintaining sensitivity and selectivity over time. My experience with vintage Drake gear confirms the value of these original documents for accurate adjustments. Furthermore, the document provides insights into troubleshooting common issues and performing routine maintenance. It serves as an authoritative guide for anyone operating or servicing this classic piece of amateur radio equipment, helping to preserve its functionality for years of DXing and ragchewing.

Amateur Television (ATV) operations involve transmitting and receiving live or recorded video and audio signals over amateur radio frequencies. Unlike narrow-band modes, ATV utilizes a wider bandwidth to convey video information, often requiring specialized transceivers, antennas, and signal processing equipment. This mode allows hams to share visual content, demonstrate projects, or conduct video conferences, typically on VHF, UHF, and microwave bands due to the bandwidth requirements. The SwissATV resource focuses on the technical aspects and community engagement surrounding ATV within Switzerland. It covers topics relevant to setting up ATV stations, understanding signal propagation at higher frequencies, and participating in local ATV activities. The site serves as a central point for Swiss ATV operators to exchange knowledge and coordinate transmissions, fostering the growth of this specialized amateur radio mode.

Presents _Beam Quest_, the official Japanese distributor for _SteppIR_ antennas, detailing their product lineup and services. The site showcases various _SteppIR_ Yagi models, including the _Dream Beam_ series (DB42, DB36, DB18E, DB11) with configurations from two to four elements, alongside the _Big IR_ and _Small IR_ vertical antennas. It also lists accessories such as TX/RX and PC interfaces, essential for integrating these advanced antenna systems into a ham shack. Operators often seek out _SteppIR_ antennas for their dynamically adjustable element lengths, which allow for optimization across multiple bands, a significant advantage for DXing and contesting. This adaptability contrasts sharply with fixed-element Yagis, providing a distinct edge in varying band conditions. The resource provides contact information, including email and phone numbers, for inquiries and support regarding _SteppIR_ products within Japan, serving as a direct point of contact for sales and technical assistance.

This simple antenna was installed on the attic. Antenna was matched with help an Automatic ATU in 40, 30, 20, 17, 15, 12 and 10 meter amateur Bands. The Antenna worked satisfactory on the above mentioned bands.

A review of the HF ham radio bands, considere by far the most popular bands in the amateur service. HF bands offer local QSOs and world-wide propagation are all possible at almost anytime with careful selection of the right frequency for the time of day, time of year, and current state of the sunspot cycle.

Sixty-meter repeaters typically use a 1 MHz frequency separation between input and output, while 2-meter repeaters commonly employ a **600 kHz** split and 70-centimeter repeaters use a **5 MHz** offset. This article details the fundamental technical principles of amateur voice repeaters, explaining how they extend VHF/UHF communication range by receiving on one frequency and simultaneously retransmitting on another. It covers essential components such as receivers, transmitters, filters, and antennas, often situated on elevated locations for optimal coverage. The resource delves into the critical challenge of _desensing_—where the repeater's strong transmit signal overpowers its own receiver—and the engineering solutions employed, including antenna separation and the use of high-Q cavity filters. It also explores various control and timing systems, from basic squelch activation to more sophisticated microcontroller-based boards that manage functions like voice identification, time-out timers, and fault protection. Different access methods are discussed, including open access, toneburst, CTCSS subtone, and DTMF, each offering distinct advantages for managing repeater usage and mitigating interference. Furthermore, the article examines repeater linking, both conventional RF methods and modern internet-based solutions, highlighting how linking expands coverage and promotes activity across multiple repeaters or bands. It introduces less common repeater types such as 'parrot' repeaters, which use a single frequency and digital voice recording, and linear translators, capable of relaying multiple signals and modes simultaneously across different bands, often found in amateur satellites.

AmTOR may be considered as the next development from RTTY. AmTOR was introduced to overcome the problems with RTTY. As a result of its performance, it has become popular on the HF bands because it gives more reliable communication, especially when interference is present. It achieves this by using a coding system that allows errors to be detected and corrected.

A trap antenna dipole covering two differen bands made reusing an old 160/80m inverted vee antenna.

My LoTW is a free viewer app for Logbook of the World by ARRL. Features include, View all the QSOs you have submitted to LoTW, Add multiple callsigns under your LoTW account, View all your QSLs, Share digital QSL image which is created by the app for QSLs. Either save it on your device or share it on facebook, View statistics for your worked stations/DXCC/bands etc

A home made portable vertical antenna, that with a single 1/4 wave counterpoise wire is possible to achieve less than 1.5:1 SWR on 40, 30, and 20 meter bands. It is basically a center load, shortened ground plain vertical antenna.

Diamond W8010 Multiband Dipole Modifications

The Southeastern VHF Society (SVHFS) is a not-for-profit organization incorporated to promote amateur radio operation on the bands above 50 MHz in the southeastern United States.

Software for Aircraft Scatter Prediction. Extend your capabilities on VHF-/UHF-SHF bands even when you live in an unprivileged location and Calculate a propagation path between two stations and follow the aircrafts in real time

Showcasing innovative RF solutions, Hofi Hochfrequenztechnik manufactures high-quality _antennas_ and RF switches. Their products, including the **versatower** and **fritzel** brands, cater to both casual operators and serious DXers. With a commitment to performance, Hofi's offerings enable operators to achieve optimal signal gain and reliability in various conditions. The company's expertise in antenna design ensures that users can effectively communicate across _HF_ bands, enhancing their overall operating experience. Whether setting up a new station or upgrading existing equipment, Hofi provides essential tools for successful ham radio operations.

Working from a small apartment-balcony on all bands with a small antenna

Monitoring extremely weak signals in the QRSS (Very Slow Morse) mode requires specialized receiving and processing capabilities to extract information below the typical noise floor. This project provides a software solution, _QrssPiG_, designed to run on a Raspberry Pi, enabling it to function as a dedicated QRSS grabber. It interfaces with various Software Defined Radio (SDR) devices, including the popular _rtl-sdr_ dongles and _HackRF_ units, to acquire raw I/Q data streams. The software then performs the necessary signal processing to visualize and decode these faint, long-duration CW transmissions, often operating with milliwatts of power. The system leverages the computational power of the Raspberry Pi for real-time signal analysis, allowing hams to participate in QRSS experiments and monitor distant beacons. It supports different SDR hardware, offering flexibility in setup and deployment for home stations or remote monitoring sites. The project includes detailed instructions for installation and configuration, making it accessible for those familiar with Linux environments. This grabber is particularly useful for tracking propagation on the LF and HF bands where QRSS activity is common, providing a visual representation of signal presence over extended periods.

To gain Tonga DXpedition Award it is necessary to have QSL confirmed contacts with two amateur radio expeditions from Tonga (A35), on two bands, with two diffrent modes. Available also to SWLs

The antenna described in this article is for 50 MHz, but the design can be scaled for any band, including VHF, UHF, or even the higher HF bands. The antenna is nothing more than a square loop of wire, approximately 30" (or ~76cm) per side. The loop is fed in the middle of one side, and the opposite side to the feed point has a gap in it.

KiwiSDR Software-defined receiver at Bjargtangar Iceland covering HF Bands

A home made magnetic loop for HF Bands. This small and compact loop is designed to support small power transmissions on HF bands, from 7 MHz to 21 MHz

Designing and constructing a two-element receiving loop antenna array for HF operation involves specific considerations for achieving high directivity and noise reduction. This resource details a homebrew system comprising two 30-inch diamond-shaped loops, spaced 20 feet apart, which are fed through mast-mounted preamplifiers and passive signal combiners. The operational principle relies on adjusting phase delays between elements via precise _Belden 8241_ coaxial cable lengths, optimized for specific bands from 160m to 20m. Performance data, derived from _EZ-NEC_ modeling, illustrates consistent 90° azimuth-plane beamwidth and low take-off angles across the target bands, with _Receiving Directivity Factor_ (RDF) values comparable to a 300-foot Beverage antenna. The article presents detailed elevation and azimuth plots for 20m, 30m, 40m, 80m, and 160m, demonstrating the array's ability to provide strong response at low DX angles while also supporting _NVIS_ signals. Key components like the _DX Engineering RPA-1_ preamplifier and _DXE RSC-2_ signal combiner are discussed, alongside the importance of impedance matching to preserve antenna patterns. The construction emphasizes self-contained elements that do not require ground radials, offering a compact solution suitable for suburban environments and stealth installations, with a focus on optimizing receive performance independently from transmit antennas.

The RBN S-Meter visualizes real-time HF propagation data from the Reverse Beacon Network (RBN). It processes thousands of automated spots per hour, providing a real-time picture of active RF paths on HF bands. Users can set their vantage point using _Region Mode_ or _Grid Square Mode_. Region Mode allows selection from broad geographic areas like E. North America or Europe, while Grid Square Mode uses a Maidenhead grid square and radius for more precise data. The app displays eight region panels, each with horizontal bars for bands 160m through 6m, indicating signal strength with a color ramp from green to red. A dimmer trail shows peak hold values, and an S-unit readout provides additional detail. The app is a free web application accessible on any device, offering a practical tool for ham radio operators interested in CW, RTTY, and FT8 signals. It features a Progressive Web App installation option for enhanced usability on mobile and desktop platforms. Users can install it on Android, iOS, and Windows devices, providing a native app-like experience. The app replaces the previous Windows standalone executable, incorporating user feedback to improve features like grid square mode and automatic location detection.

A complete guide on using the HF amateur radio bands, and the differences with VHF, using filters, influence of solar weather, the split mode and phonetic alphabets.

DL1OFC, operating from Hankensbüttel, Germany, shares insights into the fascinating hobby of amateur radio. While the station has been on hiatus since 2016, the site provides a valuable archive of activities and technical information. DL1OFC was active across various bands and modes, including 145.225 MHz FM, 430.225 MHz FM, 29.600 MHz FM, and DMR via DB0AGM on TS-1 TG-262 DL. Shortwave operations included SSB on the 40m through 10m bands, as well as 6m. The site details regional amateur radio activities in and around Hankensbüttel, offering a glimpse into local field days and community involvement. A notable feature is Die Isetalrunde, a regional amateur radio net covering the area from the Harz mountains to the sea. The site also includes general information on radio technology, tips for obtaining an amateur radio license, and discussions on VHF/HF propagation, including specifics on the 70 MHz band.

A multi-band off centre fed dipole, designed to operate on all bands from 40m (7MHz) to 6m (50MHz). Author claims it will operate on 40, 30, 20, 17, 15, 12 and 10m without an ATU (SWR <3:1) plus 6m with an ATU.

The San Bernardino Microwave Society, operating under the callsign _W6IFE_, serves as a significant technical hub for amateur radio operators specializing in frequencies above 1 GHz. This organization's influence extends across Southern California, providing a centralized resource for advanced RF experimentation and **regional frequency management** within the microwave spectrum. Its permanent value lies in its extensive archive of technical papers and project documentation, which are critical for operators engaged in high-frequency design and deployment. The society's infrastructure is primarily intellectual, focusing on the dissemination of specialized knowledge rather than a conventional repeater network. It offers a robust collection of technical papers from prominent members like K6PIP, K6BLG, and WA6EXV, covering topics such as Rubidium oscillator data, logging software, and filter design. This resource facilitates advanced amateur radio operations, including participation in microwave contests and the development of custom transverters for bands like 24 GHz. The site also details various member projects, such as the Owens Valley Radio Observatory Project, showcasing practical applications of **RF propagation analysis** and system integration. DXZone Focus: Microwave | Technical Papers | RF Propagation | Contest Results

Constructing an End-Fed Half-Wave (EFHW) antenna offers a practical solution for HF operators seeking a multiband wire antenna without the need for extensive radial systems. This design typically employs a high-impedance transformer at the feed point, matching the antenna's inherent high impedance to a 50-ohm coaxial feedline. The article specifically details a 2012 approach, focusing on a transformer with a 49:1 turns ratio, which is a common configuration for EFHW antennas. The resource outlines the construction of a wire element cut for a half-wavelength on the lowest desired band, with specific coil arrangements enabling operation on harmonically related bands such as 40m, 20m, and 10m. It discusses the physical dimensions and winding details for the matching transformer, often utilizing a ferrite toroid core to achieve the necessary impedance transformation. The content provides insights into the operational principles and practical considerations for deploying such an antenna, including methods for tuning and optimizing performance across multiple amateur radio bands. While acknowledging that the presented information from 2012 may be superseded by newer insights, it serves as a foundational reference for understanding EFHW antenna theory and construction.

The ZS1J/B beacon operates on 28.2025 MHz with 5 Watts output to a half-wave, end-fed vertical antenna, initially installed in 1977 as ZS5VHF near Durban. The 10-meter transmitter is a modified 23-channel CB radio, and the identification keyer uses a diode matrix unit with TTL ICs from the same era. After relocation to Plettenberg Bay in 1993, the beacon has been in continuous service, with additional QRP transmitters later installed for other bands. In 1994, a single-transistor, 80-meter, 0.5-watt QRP transmitter with a half-wave dipole was added on 3586 kHz, followed by a 160-meter, 0.5-watt unit on 1817 kHz. A 30-meter, 0.5-watt transmitter was installed in 1996, operating on 10.124 MHz. In 2002, a 40-meter QRRP beacon on 7029 kHz, with an output of 100 microwatts, achieved DX reports up to 1100 km from ZS6UT in Pretoria. Best DX reports for the 80m and 160m beacons came from 9J2BO.

The _Icom IC-7300_ transceiver, a popular SDR rig, can be readily configured for digital modes like FT8 using _WSJT-X_ software. This guide details the necessary steps, from downloading the correct version of WSJT-X to configuring the radio's USB audio and CAT control settings. It emphasizes a straightforward approach, aiming to simplify the often complex initial setup for new digital mode operators. K0PIR shares his practical experience, outlining the specific menu settings on the IC-7300, such as USB SEND/DPT and USB MOD LEVEL, which are crucial for proper signal modulation and transmission. The resource also covers the integration of WSJT-X's built-in logging capabilities, streamlining the process of recording digital contacts without needing external logging software immediately. This setup allows for efficient operation on various HF bands. Two embedded videos further illustrate the configuration process, providing visual aids for each step, from initial software installation to making the first FT8 contact. The author's method focuses on minimizing common setup hurdles.

This is a antenna tuner with wide range tuning for antennas with a Z of + 50 Ohms on all the HF bands.

These pages containing informations about contesting on 144MHz and higher bands. All informations are only in Czech language.

Article on operating aids and band usage during solar minimun periods. Author tries to explain what can we expect on the HF bands during a solar minimum period and which approach to be used to understand band openings.

DX Pedition to St Helena 10-80 meters bands SSB RTTY FT8 CW by G0VDE

This is a project aboout compact and portable a QRP antenna tuner for use in the HF ham radio bands from 3-30 MHz, even if it's a compact and efficient project this small antenna tuner will not match any possible load.

The Baofeng UV-5R handheld transceiver, introduced around 2012, operates across the 2-meter (144-148 MHz) and 70-centimeter (420-450 MHz) amateur bands, offering dual-band receive and transmit capabilities. This review provides an early assessment of the radio's form factor, user interface, and general performance, noting its compact size and the inclusion of a **VFO/Memory mode** button for frequency management. The device supports both FM and narrow FM modes, with a reported power output of 4 watts on VHF and 3 watts on UHF, making it suitable for local simplex and repeater operations. Key features discussed include its 128-channel memory capacity, a built-in VOX function, and a **DTMF keypad** for tone dialing and repeater access. The review highlights the radio's ability to scan frequencies and memories, along with a dual-watch function allowing simultaneous monitoring of two frequencies. Battery life is addressed, with the standard 1800 mAh Li-ion pack providing several hours of operation depending on transmit usage. Initial impressions cover the radio's construction and the clarity of its LCD display, which shows both A and B band frequencies.

The Buddistick antenna, as demonstrated by KP4MD, effectively handles up to **250 watts** and provides coverage from 40 through 10 meters, with an optional coil extending operation to 80 and 60 meters. KP4MD's video presentation meticulously describes the antenna setup, emphasizing the critical role of the _shunting coil_ for achieving resonance on lower bands like 40 and 80 meters. This practical approach highlights how a compact antenna can deliver solid performance from a constrained location. SWR curve diagrams are included, clearly illustrating the impact of the shunting coil on the antenna's resonating frequency. These visual aids provide concrete evidence of the adjustments needed for optimal operation across different bands, particularly when space is at a premium. KP4MD's insights are particularly valuable for hams operating from apartments or other limited spaces, showcasing real-world results from a balcony installation.

Thsi article describes a microcontroller driven semi-automatic antenna tuner capable of handling power levels up to 150 watts. The device is a low pass filter tuner manually tuned by setting the optimized L/C combination by hand and then storing the values into the EEPROM of the mictrocontroller to recall them later (seperately for each band from 80 to 10 meters including WARC bands)

Gimme Five reloaded, a compact 5 band QRP SSB transceiver in SMD technology. This unit covers 5 bands within the amateur radio spectrum (3.5, 7, 14, 21 and 28 MHz). Receiver is a single conversion unit with an interfrequency of 9 MHz. Transmitter uses 5 stages and has got a power level of 10 watts PEP output.

IARU HF Contest, goal is to contact as many other amateurs, especially IARU member society HQ stations, around the world as possible using the 160, 80, 40, 20, 15 and 10 meter bands.

A not-for-profit organization incorporated to promote ham radio operation on the bands above 50 MHz in the southeastern United States.