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An ham radio contest log sheet in a PDF US letter printable format, can be used for portable operations, free to print and download.

Throughput improvement for the FT726R - Tapr PSK modem

IARU Region 3 bandplan Revised 12 March 2019

Antennas and Accessories for Satellite Radio and AM FM HD Short Wave Radio, satellite antenna, shortwave magnetic loops.

Presents the construction of a 2-meter **Skeleton Slot Yagi** stack, detailing the design process and practical considerations for VHF operation. The author shares insights from building and testing this antenna, emphasizing its performance characteristics for local and extended range contacts. The project outlines the specific dimensions and materials used, providing a clear path for other radio amateurs to replicate or adapt the design for their own stations. The resource covers the unique aspects of the Skeleton Slot radiator, explaining how its geometry contributes to gain and pattern control. It includes discussions on impedance matching and feedline considerations crucial for optimizing power transfer and minimizing SWR. The article draws on real-world testing, offering practical results that validate the theoretical design. This project serves as a valuable reference for those interested in custom VHF antenna solutions.

The MRAC is one of the oldest amateur radio clubs in the world, having been incorporated in 1917 and affiliated with ARRL

Assembling the Butternut HF9v HF vertical antenna

A handy piece of test equipment useful for HF bands, can absorb a 200W modulated carrier for almost 2 minutes. It is housed in a tin and part filled with dry sand that helps in power dissipation

Operating a modern amateur radio station often involves integrating various software tools, and LogHX aims to provide a unified environment for Windows users. The software facilitates comprehensive QSO accounting, allowing operators to track contacts and manage both e-QSL and traditional paper QSL exchanges, including via QSL managers or direct methods. It also offers real-time QSO preview and integrates with popular callbook data for quick lookups. LogHX supports various logbook database searches and maintains statistics for numerous awards, a critical feature for serious DXers and contesters. The program handles logbook import and export in widely used formats such as _ADIF_ and _Cabrillo_, ensuring compatibility with other logging applications. Furthermore, it interoperates with Telnet clusters and third-party ham radio software, enhancing its utility in a networked shack environment. Key functionalities include antenna rotator control, editable macros for PSK, RTTY, CW, and SSB operations, and CAT control via _OmniRig_ or direct interfaces. Embedded modules like MMVari, MMTTY, and CWServer streamline digital mode operations, while its multi-window structure allows users to customize their screen layout, preserving valuable monitor space.

Building a Resonant Feed line Dipole for 2 Meters

Presents a detailed resource for DXers interested in Non-Directional Radiobeacons (NDBs), MF, HF, and VHF propagation beacons, and various other radiobeacon types. The site offers access to downloadable information files, including an Abbreviations List, NDB List Country List, and NDB Publications List, which serve as foundational materials for newcomers to the hobby of beacon monitoring and DXing. It covers specialized topics such as DGPS beacons, GMDSS DSC mode, and NAVTEX mode, with dedicated sections providing in-depth explanations. A Beacon Photo Gallery showcases diverse radiobeacon types from around the globe, offering visual context for different systems encountered in the field. The platform also facilitates participation in unique monthly Coordinated Listening Events (CLEs), providing guidelines and schedules for these activities. The resource outlines various associated Groups.io lists, including the primary NDB List for radiobeacons (NDBs, Propagation Beacons, VOR systems), the DGPS List for DGPS DXing, Time Signals, LORAN, and WeFAX modes, and specialist groups like NavtexDX and DSC List for GMDSS-DSC. It details how to join these communities for further engagement and information exchange.

An off-center-fed sleeve dipole, made of CPVC and aluminum foil tape by KV5R

50 MHz extended 6-7 element ZX-Yagi antenna. Dimensions for the 7 elements and information on performance of a 2 stacked antennas featuring a total max gain of 20.8 dBi

Clevaflex is a manufacturer of flexible wound tubing that can be used in a variety of applications. our unique manufacturing process allows tubes to be designed and built with a multi-ply convoluted wall contour that creates a permanently bonded tube.

DK0WCY transmits 24 hours per day on 10144 kHz in the 30 meter amateur radio band. QTH in Scheggerott JO44VQ

Amateur Radio Sales from North Central Texas

An article (in Finnish) on LiPos in the FT-897 ad alternative to FNB-78 published in Radioamatoori 12/2011

The Lake Monroe Amateur Radio Society serves Seminole County and Central Florida, operating two 2 meter repeaters on 147.285 +600 and on 146.805 -600

Slow Scan TV History from 1957 till today

The supporting structure is a 15-m-glassfibre mast of DX-Wire. The antenna can be used on all bands from 10 to 40 m.

Restoration and sale of quality antique radios that work, backed by professional testing, restoration, and warranty. vintage hi-fi included.

VK Contest Log (VKCL) is a free contest log software specialising in Australasian contests but also covering some international ones too. Author is SK, you can donwnload the latest version 4.15.

Globe-S for RTL1090 is a light radar viewer for RTL1090. It communciates via a HTTP interface and can be interfaced over long distances.

Distributors of specialty metals, electricial wire & cable, and high capacity magnet mounts for government and business. Stainless steel bars and rods for nuclear applications.

75m Mobile Texas Bugcatcher Loading Coil Measurements

Air conditioning soft copper tubes are perfect for loop construction. If you want to try a loop you must have an air variable capacitor or a vacuum variable capacitor. Article by PY1AHD

Pictures and description of a SteppIr vertical antenna setup in a small backyard using DX Engineering radial plates.

A 200 kHz bandwidth digital transmission system for image transfer in the Amateur Service is under development, specifically targeting VHF allocations. John B. Stephensen, KD6OZH, leads this project under an FCC Special Temporary Authority (STA) valid until September 10, 2006, authorizing emissions up to 200 kHz bandwidth in the 50.3-50.8 MHz segment. Current regulations typically limit bandwidths to 20 kHz on VHF amateur bands, making this STA crucial for testing wideband digital modes. The modem, a modified **OFDM** (Orthogonal Frequency Division Multiplexed) unit, was initially tested on the 70-cm band. It splits a high-rate data stream into multiple low-rate subcarriers to mitigate multipath echoes. The system uses a DCP-1 card with a Xilinx XC3S400 FPGA and Oki Semiconductor ML67Q5003 microcontroller. The transmitter, located at 36d 46m 30s N, 119d 46m 22s W, generates 150 WPEP into an 8 dBi gain vertical antenna, while the mobile receiver uses a Ham-stick. Three data formats for 50, 100, and 200 kHz channels are being tested, with encoded data rates of 96, 192, and 384 kbps. Verilog code for the VHF OFDM modem is 95% simulated, with modifications from the UHF version including increased filter coefficient precision and a change from Ungerboeck **TCM** to BICM for improved performance over fading paths. Final tests will involve one-way over-the-air measurements of bit error rates and coverage area.

PDF File of the Kenwood TM-710A user manual

The club was established in 1975 with the purpose to further the exchange of information and cooperation between members, to promote knowledge, to prepare for service in the community in time of disaster or need for emergency communications,

HB9BZA's LoTW users list, originally compiled since 2005 from DX-Cluster and user submissions, now primarily leverages the official ARRL full users list released on July 29th, 2017. This resource details 228,012 calls across 340 current DXCC entities, with the latest update noted on March 2, 2026. It offers various formats, including a full list, text versions, and breakdowns by country, providing valuable insights into LoTW participation for DXers. While the ARRL's official list with "last upload" dates diminished the original list's unique utility, HB9BZA's site continues to offer statistics and user counts by country, which remain of interest. The author, HB9BZA, expresses gratitude to contributors who helped maintain the list's accuracy over many years, achieving an impressive 96.4% match with the ARRL's data before the official release. Knowing which stations are LoTW active encourages more hams to join the system, demonstrating that even rare DXCC entities like Ducie Island or Heard Island can be confirmed quickly. For instance, HB9BZA recounts a 36-minute QSL confirmation for a 3A2MW contact. The list also integrates with the RXCLUS packet radio/telnet client, enhancing DXCC award tracking by identifying LoTW participants and utilizing upload dates for alarms.

St. Louis Repeater runs four repeaters in the St. Louis Metro Area, including two with autopatch capability.

Chesterfield Islands DXpedition 2000

The W3EDP is a 85 foot long wire and a 17 foot counterpoise. At N4KGL

The **136kHz Vertical Antenna** at G3YMC employs a Butternut HF2V structure, standing 10m tall. It integrates a 6.5mH loading coil to achieve resonance, with a matching transformer for impedance adjustment. The antenna's configuration includes top loading via a 12m horizontal wire, enhancing capacitive impedance. Initial measurements indicated a high impedance of around 300 ohms, necessitating a transformer for a 50-ohm match. Despite challenges with ground losses, the vertical antenna has shown improved performance in specific directions, filling nulls present in the previous loop antenna setup. The tuning remains broad, with variations due to environmental factors affecting the matching. Ongoing adjustments and comparisons with the loop antenna will continue to refine its effectiveness.

An easy to build with a cheap HEMT FET Transistor Low noise preamplifier with FHX35LG based on JH0WJF design

This is a concept paper, not a constuction article. There are too many variables to propose a one size fits all design. However, this paper should give you the basic idea how to do it

The goal of detuning is not to avoid resonance, but rather to minimize re-radiation and/or current in the interfering structure.

colombian ham radio stations,radioaficionados colombianos,dx,qsl,photos,fotos

An SSB radio for the HF bands will be presented. Featuring 12 to 20 Watts of output power (depending on DC supply), full DDS frequency generation, covering 6 major frequency bands (1.8, 3.5, 7, 14, 21 and 28 MHz) within the short wave amateur radio spectrum. The rig also features colored LCD and front panel backlight.

RigPix Database: Kenwood TS-50, pic and specifications, link to user manual

kv5r 2 meter antenna

Contesting resource pages by OH1NOA

Welcome to SW2A special contest station, with photos, logs and results

This resource provides a unique historical audio archive of 50 MHz DX contacts, documenting significant F2 and Es propagation events experienced by PA2S (formerly PA2HJS) since 1978. The collection includes recordings of beacons and two-way QSOs with stations across North America, South America, Asia, Australia, Europe, and Africa. Specific entries detail contacts with rare DX entities such as ZS6PW, VE1AVX, C5AEH, J52US, TR8CA, LU8MBL, VK8ZLX, and various Japanese stations, often noting the mode (SSB or CW) and propagation type. The archive also highlights challenging pile-up situations and frustrating near-misses during major openings. The recordings, initially in RealAudio format for solar cycles 21 and 22 and later in MP3 for cycle 23, offer a practical illustration of 6-meter band conditions over several solar cycles. The content allows hams to listen to actual signals from different continents, observing signal characteristics like typical TEP fading from 5H3RA or strong F2 backscatter from OZ1BVW. It provides a comparative perspective on propagation effectiveness between solar cycles, noting that cycle 23, while not as robust as previous cycles, still yielded interesting openings. The archive serves as a valuable educational tool for understanding real-world 50 MHz DXing and propagation phenomena.

Indiana's fastest growing hamfest! Saturday, November 29, 2003

Article explaining electronic network of low pass filters

TSC International produces soft magnetic sheet steel, custom-stamped and heat-treated to achieve optimal electrical characteristics for applications such as motors, generators, linear power supplies, and ballasts. The company's manufacturing process focuses on precise material engineering to meet specific performance requirements in various electrical systems. They also specialize in soft magnetic core materials essential for transformers, chokes, and inductors. These core materials are utilized in power supplies, lighting ballasts, signal conditioning circuits, inverters, and battery chargers, providing critical magnetic properties for efficient energy conversion and signal integrity. Located at 39105 Magnetics Blvd, Wadsworth, IL 60083-0399, TSC International provides contact via sales@tscinternational.com or phone at +1 (0) 847 249 4900, facilitating direct inquiries regarding their magnetic component offerings.

A 13 CM signal source project by W6PQL