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International postage stamps by K3FN

Have you ever thought of setting up a portable HF station for an activity like the Field Day ?

A detailed review of the Icom IC-7700 by VA7OJ/AB4OJ

eHam reviews of the Icom IC R7100 VHF UHF receiver

The official club site of K7UAZ.

A document that will guide you on Coaxial-Cable trap optimization process to gain on global antenna performance and on increasing effective bandwidth.

PRO-LINK specializes in the manufacturing and distribution of high-quality cabling solutions, including a wide array of fiber optic cables and various coaxial cable types. Their product line encompasses 50-ohm and 75-ohm coaxial cables, essential for diverse RF applications, alongside specialized RF cables and 10Base-T networking cables. The company also provides a selection of connectors and custom cable harnesses, catering to specific installation requirements. Since 1988, PRO-LINK has offered a 5-year warranty on its products, underscoring a commitment to durability and performance. The product catalog details specifications for different cable constructions, such as _RG-58_, _RG-213_, and _LMR-400_ equivalents, which are commonly used in amateur radio installations for antenna feedlines and inter-component connections. Their offerings support both commercial and amateur radio operators seeking reliable signal transmission. The company's focus on robust cable and connector solutions addresses the critical need for low-loss transmission lines in radio communication systems, ensuring signal integrity across various frequency bands.

A project about reversible unidirectional Beverage antennas plus a remote switching system conveniently controlled by the operator

Turning an RV marine battery into a massive 12-volt emergency power source

A 60-foot available space, for example, might necessitate a shortened multiband dipole array to cover 80, 40, and 15 meters effectively. This resource details the construction of such an antenna, combining full-size and coil-loaded dipoles on a single feedline. It addresses the common challenge of fitting multiple HF bands into restricted physical footprints, providing practical guidance for hams with smaller backyards or portable operations. The core of the offering is an interactive calculator that determines required loading coil inductance and dipole lengths for various amateur bands from 160m to 10m. Users input their available space, and the tool provides dimensions, coil turns, and an efficiency rating (Good or Fair) based on the antenna's electrical length relative to a quarter-wavelength. It also suggests suitable _PVC_ pipe diameters for coil forms. The article further illustrates a center feed-point assembly using an 18-inch section of 2-inch _PVC_ pipe, detailing eye-bolt spacing and coaxial connector installation. It emphasizes the importance of adequate spacing between parallel dipoles and offers customization options for the feed-point, including the addition of a _Balun_ for improved feedline isolation.

Frequency agile 80 metre CW QRP transmitter. Ceramic resonators vary in the frequency shift obtainable. The one in the prototype of this article gave 3.525 to 3.558 MHz coverage.

Fractional Wave Loops antennas are a sort of magnetic loop antennas that differs in several aspects from the standard ones. Author is now SK however in his page he posted several examples and interesting links

Amateur radio news, events and other electronic stuff by KE2YK

Ham radio blog by KU7PDX Chris Arnesen

Custom cases and stock cases

E51LYC DXPedition to Pukapuka atoll OC-098 North Cook Isl 2017

Tips on QSLing. Once you work that DX station, you have won the battle, but the war may just be beginning. I am talking about getting the QSL card. There are several ways to go about this.

Collection of several topics on antenna tuners and their performance. Why use an antenna tuner? How does an antenna tuner…tune Does an antenna tuner fool the radio? Will an antenna tuner waste power? Can an antenna tuner help get more power to the antenna?

A multiple page article about assembling the antenna system, this section includes informations on constructing of the concrete tower base, starting from setting up correctly the foundations in relation to the antenna height.

A review of the SteppIR UrbanBeam antenna a two element Yagi antenna working 40-6 meters. The UrbanBeam is a good choice for those thare are limited by lot size, regulations, city regulations.

Mali DX Pedition by Italian DXPedition Team 2012

This article discusses how volume reduction can help in the reception of weak signals by reducing the noise level. It is commonly known that reducing the volume also reduces the background noise, and especially in the reception of weak digital signals it can be beneficial

This project enhances Arjan te Marvelde's uSDR-pico by integrating a waterfall display feature. By adding an ILI9341 240x320 2.4" TFT display and modifying the software, the goal is to provide a panadapter to the existing transceiver. Initially developed with Visual Studio, the code was later migrated to Arduino IDE for Raspberry Pi Pico compatibility. The focus remains on preserving the original software, primarily enhancing the dsp.c file for waterfall implementation.

F5NPV introduces a variant of the W8JK antenna design, employing the MOXON principle. With extended monopoles, it outperforms the Open-Folded W8JK, yielding a 1dbd gain improvement, enhanced performance on 30m and 10m bands, bi-directionality, and lower side attenuation. The design's focus on higher radiation impedance results in increased antenna efficiency and reduced losses. Despite these improvements, the bill of materials remains unchanged.

A weekly net for new and returning hams, runs every Saturday from 00:00 - 01:00 UTC and can be heard across the world. During the weekly F-troop there are mentions of software, websites and solutions that are worth taking note of. This website attempts to document them.

Worked other amateur stations in each of the six continental areas of the world using Collins equipment two-way

Republic of Niger 2017 5U5R DXpedition web site 2017 Mar 9 - 2017 Mar 2 Will operate 160 to 10m, also 5.360 MHz; SSB CW RTTY; QSL via EA5RM

Radioaficion,satelites,APRS,DX,scanner,radioaficionado,PSK31,by EA1URO Union de radioaficionados de Ourense Espana

The Icom IC-7300 is a popular SDR transceiver known for its excellent performance in ham bands. However, users have reported issues with reception reliability outside these bands due to ADC aliasing. This phenomenon occurs when the sampling rate of the radio interacts with frequencies outside the intended range, leading to unwanted signals being received. For instance, when tuned between 30 to 36 MHz, users may inadvertently pick up WFM broadcast signals or PMR communications due to aliasing effects. This guide outlines modifications to improve the IC-7300's performance by addressing the low-pass filter design, which is crucial for reducing interference from these unwanted signals. The proposed modifications involve adjusting the low-pass filter on the PA unit to better attenuate frequencies that cause aliasing. Measurements indicate that the original filter design allows significant signal leakage, leading to false receptions. By implementing the suggested changes, users can achieve a notable reduction in unwanted signals, enhancing the overall functionality of the IC-7300. While the modification requires careful soldering, the benefits in performance make it a worthwhile endeavor for serious operators looking to optimize their SDR experience.

Yaesu FT-8800R programming with FTB8800 by G4HFG

Sponsored by The Columbia Amateur Radio Club

A review of the dual band FT-8800R transceiver by the jeep expedition group

A pocket-sized homebrew 40m CW QRPp/QRP transceiver

Microwaves101 provides an extensive repository of information covering fundamental principles of microwave design, targeting engineers and radio amateurs interested in the higher frequency spectrum. The site features a detailed _encyclopedia_ of microwave terms and concepts, alongside practical design considerations for various components and systems. It serves as a foundational reference for understanding RF propagation, transmission lines, and active/passive microwave circuits. The resource includes numerous calculators for impedance matching, filter design, and other critical RF parameters, facilitating hands-on project development. Discussions on **10 GHz** equipment and **24 GHz** projects highlight practical amateur radio applications, extending to operations up to 134 GHz. Content spans from basic theory to advanced topics like MMIC design and antenna characteristics, supporting both educational and practical endeavors in microwave technology.

OY/DL3UB , Faroe Islands (29. July - 09. August) verticals + PA (max 500w) WARC bands cw

If your club holds only two-meter ARDF events, you are missing half the fun. There is another international foxhunting band, too.

Testing a Bencher YA-1 low-pass TVI filter with a spectrum analyzer with tracking generator.

GREENSTONE USA leader in the Vacuum Industry manufacturing products such as Vacuum Tubes, Vacuum Capacitor, Vacuum Relays, Vacuum Contactors and Vacuum Interrupters.

Experimental Methods in DSP design. The author explains how a software defined radio works to help other amateurs with their learning. This set of tutorials takes you from how to write a single component to a fully working SDR.

Design and manufacture antennas for mobile devices, wireless data including WiMAX, WiFi, and WISP (Wireless Internet), two-way radio and RFID (Radio Frequency Identification).

Malcom Technical Support Radio Electronics Repair, ICOM Authorized Service Center, also service 1988 and newer Kenwood HF/VHF/UHF transceivers based in Toledo, WA USA

South east africa indian ocean Amateur Radio adventure Seychelles 2010 m July 17 th until July 31th by ct1bww

YT9X Serbja contest team

A vertical antenna for 160 meters band based on the K6MM vertical with some enhancements and modifications on the main capacitance hat

The Salvation Army Team Emergency Radio Network (SATERN) is a vital resource for amateur radio operators involved in emergency communications. This network facilitates the coordination of communication during disasters, ensuring that vital information can be relayed effectively. SATERN operates through a series of nets that connect operators across various regions, allowing for real-time updates and support during emergencies. Participation in SATERN not only enhances your skills as an amateur radio operator but also contributes to community resilience. Operators are trained to handle emergency traffic and provide assistance to those in need. By joining SATERN, you become part of a dedicated team that prioritizes safety and communication in times of crisis. The network encourages regular participation in drills and training sessions to ensure readiness when real emergencies arise.

T31A Kanton Island 2011 DXpedition official website

The Texas Slow Net (TSN) operates daily at 7:45 PM local time on 3570 KHz, serving as a dedicated traffic handling training net within the National Traffic System. It specifically caters to operators aiming to enhance their **International Morse Code** skills and learn proper CW traffic net procedures. Each session incorporates a traffic handling lesson delivered as a radiogram to all participants, reinforcing practical application. The resource provides guidance on effective Morse Code learning, emphasizing sound recognition over visual dot/dash counting, suggesting characters be sent at 15 words per minute with adjusted spacing. It recommends listening to W1AW code practice transmissions, setting goals with ARRL's Code Proficiency Program qualifying runs, and regular participation in NTS traffic nets. The content also references the ARRL's Public Service Communications Manual, particularly Section 2, which details the **National Traffic System**.

Time Mapper UHD is a versatile mapping and time visualization program offering multi-satellite viewing with frequency display and unique country-pairs for PskReporter data. It features live feeds from logging programs and can plot ADIF files. Ideal for schools, offices, or amateur radio stations, it provides customizable 4K or HD world clock displays with over 60 map layers, including ham radio zones and natural features. The program supports various time functions and can import logs for detailed analysis. It runs on Windows 10 or 11 and offers a 30-day free trial.

Useful Function for the Drake TR-7(A) \"Store\" Switch Add A Transmit Key Function

TRS RenTelco provides new or used electronic test equipment for rent, lease or purchase. Solutions are provided for various type of equipment such as spectrum analyzers, network analyzers, oscilloscopes etc from leading manufacturers. Our products are widely used in communications, R&D, semiconductor, and wireless industries.