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Simple 6 Metre DX Antenna based on an article by LB Cebick in QST May 2002 on a Quad Turnstile antenna. This antenna is basically two full wave loops mounted at right angles fed 90 degrees out of phase to produce an omni-directional horizontally polarized pattern

A collection of drawings of most popular wire antennas for hf ham radio bands

Taking the Raspberry Pi 2 for a Test Drive with GNU Radio. Installing GNU Radio and receiving aircraft radar with a USB TV tuner

Projects you can build, an amplified shaped sine-wave oscillator

This method of construction can be used on most UHF through \"low\" microwave Yagis, and is especially useful for the 33, 23 and 13 cm bands

Digital voice on Amateur Radio - devoted to the discussion of digitized voice and data over analog emission modes.

21 28 and 50MHz three bands whip antenna by JA1HWO

Free radio nova on Shortwave

The antenna is comprised of three lengths of 12 foot aluminum which telescope together.

An home made transmitter for 40m CW

HFpack provides an information exchange about transceivers, antennas, systems, HF packs, propagation, new developments and techniques in HF portable operation. Radio Amateurs are invited to participate in egroup and on-the-air nets around the world.

SDRplay limited is a UK company and consists of a small group of engineers with strong connections to the UK Wireless semiconductor industry. SDRplay announced its first product, the RSP1 in August 2014

Constructing a high-power 70cm solid-state amplifier presents unique challenges, particularly when aiming for 500 watts output using modern LDMOS devices. This resource details the author's experience building a 70cm amplifier based on a _Freescale MRFE6VP5600H_ transistor, initially from an RFHAM kit. It meticulously outlines the necessary modifications to achieve advertised performance, including optimizing input and output matching, correcting bias circuitry, and ensuring proper output balun connections for stability. The author shares specific adjustments, such as trimming the prototyping board for better transistor fit, drilling additional mounting holes for improved heat sinking, and replacing original matching capacitors with a single _20pf MIN02 metal mica_ for superior output. A critical fix involved jumpering gate decoupling pads to balance the push-pull transistor halves, which increased output to 580W and improved IMD. The resource also highlights a crucial correction to the output balun connection, initially reversed in the _Dubus_ article schematic, which resolved intermittent stability issues. Test results are provided, showing input power, output power, and drain current at 50V, demonstrating the amplifier's performance after modifications. This practical account offers valuable insights for hams undertaking similar high-power UHF amplifier projects, especially those working with LDMOS devices and kit-based constructions.

Picture and specifications of the Yaesu VX-2R at RigPix

An home made FETer QRP transceiver for the 80 meters band

The Icom AH-4 autotuner operates efficiently across multiple HF bands, providing seamless automatic tuning for antennas from 3.5 MHz to 54 MHz. Its robust design allows for outdoor installation, making it suitable for field operations and fixed stations. The unit interfaces with Icom transceivers via a control cable, enabling automatic band switching and tuning. The AH-4 is capable of handling up to 120 watts of RF power, ensuring compatibility with most amateur radio setups. Its weather-resistant casing and compact form factor make it a versatile choice for operators requiring reliable performance in diverse environments. Field tests demonstrate the AH-4's ability to maintain low SWR across its operational range, enhancing signal quality and transmission efficiency. Compared to manual tuners, the AH-4 offers significant time savings and ease of use, particularly in rapidly changing band conditions. Its integration with Icom radios simplifies operation, eliminating the need for manual adjustments. The autotuner's performance is consistent with other high-end models, providing a cost-effective solution for amateur operators seeking dependable tuning capabilities without sacrificing performance.

A DIY Automatic Band Decoder (ABD) project, designed for dual-radio operation, addresses the common challenge of integrating band data with older transceivers lacking dedicated outputs. This particular build utilizes an AVR AT90S8515 microcontroller and a 16x2 Liquid Crystal Display (LCD) to provide band information, specifically targeting Kenwood rigs via a computer's LPT port. The design aims for cost-effectiveness while maintaining functionality, offering a solution for hams seeking to add automatic band switching capabilities to their station without significant expense. The project outlines the core components required, including the microcontroller, LCD, and an enclosure, noting that the Printed Circuit Board (PCB) fabrication and AVR programming might present challenges for some builders. It details the input requirements, such as a four-pin input and PTT for each radio, along with a 13.8V DC power supply. The decoder provides 2x6 outputs capable of sinking 500mA, suitable for controlling external devices like antenna switches or filters. Despite the original unit being damaged by a lightning strike in 2004, the author confirms its successful operation prior to the incident and mentions plans for a revised version. The resource includes a schematic in PDF format and images of the finished PCB and assembled unit, demonstrating the practical implementation of the design.

Ea2id demonstration video of the Ameritron AL-811H in spanish

Design and build a 6 meter 2-element Moxon antenna mostly from available aluminum tubing and angle stock.

Log Online for FT4JA Juan de Nova DX Pedition

Examines JPS Communications' product offerings, focusing on their contributions to Radio over IP (RoIP) and Push-to-Talk over Cellular (PoC) technologies. The resource details how JPS solutions enhance Land Mobile Radio (LMR) capabilities by providing secure and cost-effective methods for communication expansion and interoperability. It highlights the company's 30-year history in developing infrastructure to make communication systems more versatile, secure, and robust, addressing critical needs in various operational environments. The content specifically outlines JPS gateways that bridge traditional radio systems with PoC solutions, facilitating seamless communication across disparate technologies. It also describes multiple approaches for expanding LMR coverage beyond conventional system limitations. The information presented underscores the practical application of these technologies in achieving communications interoperability, irrespective of the underlying systems or protocols, aiming to improve operational efficiency and safety.

Radio New Zealand International is a Shortwave Broadcaster. Our broadcasts are beamed to the island nations of the Pacific but can also be heard in other parts of the world.

Online Log and dx info for Southern Line Islands DXpedition 2010

A simple free running oscillator oscillating at the receiver\'s IF (intermediate frequency) beats with the incoming signals in either CW or SSB and the resultant audio frequency goes to the AF amplifier.

There are many designs for building preamps each with their own advantages and disvantages. In this PDF Article author reviews several different types.

ozQRP offer a range of kits to build a complete QRP SSB transceiver

Pictures and design plan of a 28 MHz - 70 MHz transverter 3Watts in - 8Watts out by 9A2SB

SWL DX bulletins in spanish

Presents Eagle Stainless Tube & Fabrication as a certified distributor specializing in various tubing products essential for antenna construction and other amateur radio projects. It details their offerings, which include aluminum tubes in fractional, metric, and heavy wall specifications, alongside stainless steel bar stock in round, square, and flat profiles. The resource highlights the availability of a diameter sizing chart and direct contact options for specialists, indicating a focus on providing specific material dimensions and expert support for custom fabrication needs. The company emphasizes its role as a supplier of raw materials, crucial for hams engaged in DIY antenna builds or structural components for their shacks. Their inventory supports the precise mechanical requirements often encountered in radio frequency engineering, where material strength, weight, and corrosion resistance are critical design factors for outdoor installations. The site primarily serves as a product catalog and contact point for sourcing specialized metal tubing and bar stock, providing technical specifications and material grades relevant to robust amateur radio infrastructure.

Yaesu vx-8r prototype quad-bander on display at the 2008 dayton hamvention. Youtube video

The author who works successfully via EME on this band wants to describe his own yagi design and give some of hints for the construction. by Heinrich F. Reckemeyer, DJ9YW

A well documented PDF document containing picture sequence taked during the repair of an Icom IC-7700 HF transceiver power amplifier module

Unaffiliated amateur radio group based in New Castle, Pennsylvania dedicated to having fun on the HF bands

Learn quadrature modulation through interactive flash programs. These programs will allow you to learn about quadrature modulation and quadrature demodulation without getting overwhelmed by math.

Solar panels, solar and wind home power systems, pre-wired power panels. Wholesale prices for everybody. Free solar design.

Optimizing weak signal reception on the HF bands, particularly in the presence of strong local QRM, often necessitates specialized receiving antenna systems. This resource details the _HI-Z Antennas_ product line, focusing on phased vertical arrays designed for superior noise rejection and directivity. It covers components such as the 4-Square and 8-Element array controllers, which allow for rapid switching of receive patterns, and dedicated low-noise preamplifiers to improve system sensitivity. The site also presents various bandpass filters, crucial for mitigating out-of-band interference and enhancing the dynamic range of the receiver. The HI-Z systems are engineered to provide significant front-to-back and side rejection, often yielding **20-30 dB** of attenuation to unwanted signals, which is critical for DXing and contesting. Users can achieve a notable reduction in local noise, allowing for the discernment of signals that would otherwise be buried. The array controllers facilitate quick pattern changes, enabling operators to null out interference or peak weak signals from distant stations, effectively extending the reach of their receive capabilities by improving the signal-to-noise ratio.

T32 DX peditions logs, T32CI T32MI T32SI T32VI

Techni-Tool is a distributor of electronic production tools, oscilloscopes, multimeters, power supplies, cases, tool kits, cutters, wrenches, crimpers, solder desolder stations, BGA, microscopes, lamps, static control, workstations, chairs, torque screwdrivers, tweezers, dusters, chemicals.

Excellent article and guide to choose the best RF power amplifier that fit your needs by ON4SKY

W9dc north america amateur radio checkpoint for iota islands on the air and wlh world lighthouse award applications and award instructions

Online Log 9U4U

Offering transient voltage surge suppressor, TVSS, patch cables, surge arresters, surge protectors for lightning and power surge protection for electrical equipment, IT networks, communication systems, data lines, relay systems and solid state controllers.

Video on Baofeng uv-3r menus

Presents the **BayCom** packet radio system, detailing both its hardware and software components specifically designed for amateur radio use. The resource offers insights into the technical specifications and operational aspects of the BayCom modem, which has been a staple for many German packet radio enthusiasts. It covers the integration of these components within a typical amateur radio station setup, enabling reliable digital communication. Further, the site provides a broader context by including general information about the German packet radio network. This encompasses network topology, operational protocols, and historical developments relevant to packet radio in the region. Users can find details on how to connect to and utilize the existing infrastructure, fostering participation in the local digital amateur radio community.

Amateur, scanner, wi-fi and land mobile antennas and accessories online store

York Region Amateur Radio Club, one of Canada's largest

Ham radio wire antennas are the most common form of antenna used by ham radio operators. Here you can find hints and tips on diy wire antennas

Welcome to the home page for the Lake Area Amateur Radio Klub (K5LRK) located in southern Denton county, Texas