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Design for a dual-band CW transceiver using the AD9834 Direct Digital Synthesizer

The Pecker is a software application that emulates an existing hardware amplifier tuning aid operated in SSB mode as apposed to CW or AM. As such no carrier is used by G7EIX

HSMM Experiments on the 6M Amateur radio Band

Topband and DX recordings and sound files on 160 meters band

The fan dipole antenna as an alternative to the paralled dipole antenna, to achieve a larger bandwidth and a better tuning by decreasing elenment influences.A project based on the W6HDG original concept.

A new, simple way to build the Eggbeater Antenna. This document introduces a new, simpler way to build the Eggbeater antenna. It also introduces a technically proper way to construct the Eggbeater antenna in order to achieve the best result.

This online WebSDR is located near Corinne, Utah, has coverage on all U.S. amateur HF, MF and LF bands, 2 meters, the bottom 1 MHz of 6 meters, and several shortwave broadcast bands.

An interesting article on guanella baluns that cover several aspects of homebrewing 1:1 and 4:1 current baluns by KN9B

Concentrating on VHF DX, Aurora, Meteorscatter, TEP, Sporadic E, EME, VHF DXpeditions. Daily updates.

The Northern Alberta Radio Club serves Edmonton, Alberta and area.

Supplying over 2000 different vacuum tube types, valves, grid caps, sockets and capacitors. It is easy for Antique collectors, Ham radio operators, audio enthusiasts, broadcast enthusiasts and amateur radio hobbyists to buy, sell and trade vacuum tubes, electron tubes, audio tubes, valves, grid caps, sockets and capacitors

A led electroluminescent radio receiver

Xenia, Ohio Ham radio club, formed because of the Tornado of 1974.

**LDG Z100** automatic tuner repair focuses on toroid replacement and troubleshooting. The guide provides detailed steps for diagnosing and fixing common issues with the toroid, which is crucial for the tuner's performance. It includes specific instructions on disassembling the unit, identifying faulty components, and sourcing replacements. The document is technical, requiring familiarity with electronic components and soldering techniques. It emphasizes the importance of using the correct toroid specifications to ensure optimal functionality. Successful repair of the **LDG Z100** ATU restores its ability to match a wide range of antennas, enhancing transmission efficiency. The guide compares the performance before and after the repair, highlighting improvements in SWR readings and overall reliability. Practical application of this repair extends the life of the tuner, making it a cost-effective solution for amateur radio operators. The document serves as a reference for similar repairs on other models, providing insights into common issues and solutions. It is a valuable resource for those looking to maintain their equipment without resorting to professional services.

Radio astronomy research at the University of Calgary

A Portable 100 watt radio station setup composed by a 706MKII transceiver, Z-100 antenna tuner and power supply by N1GY

Manufacturer of fiberglass parts for kites

Stop common-mode current when transmitting with an end-fed antenna. Unbalanced antennas are very prone to currents on the outside of the coax.

Notes on using the QST propagation charts to determine propagation conditions

A NEC Model Comparative Analysis of Physical Orientation and Performance. The small magnetic loop is a useful compromise antenna for limited space and portability. For this reason, the magnetic loop antenna is a practical high frequency antenna solution for the restricted space of apartment dwellers

A great resource for new Hams, those who want to become new Hams, or those who just need a refresher. The site offers some good video courses to help prepare for the exams.

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.

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.

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.

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

kv5r 2 meter antenna

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.

Alexander The Great AWARD from Northern Greece Contest Team

The IC-756, a Step Forward for HF and six metre DX by Frank van Dijk, PA3BFM

The latest info on the world of radio including:world,shortwave,pirate,digital,mw,lw news,links.

Yaesu VX-150, VX-170 BATTERY questions

A website dedicated to 70 MHz Band

W4TI Rotator Installation

A wire antenna feeded with an unsymmetrical feed and a 1:4 balun can be tuned from 6 to 80 meters band but can be noisier than a dipole and cause RF in the shack

22 Different Wire Antennas for the 160 Meter Band, Random Length Radiator Wire, delta loop, loop antennas, off-centered antennas, sloper, dipoles, Z antenna, Zepp and Clothesline Antennas

Presents the Holy Cluster, a contemporary DX cluster service offering real-time amateur radio spot data. This platform integrates a dynamic graphical map to visualize current contacts, enhancing situational awareness for DXers and contesters. Developed by an Israeli group of developers and supported by the Israeli Association of Radio Communication (IARC), the Holy Cluster aggregates DX spots from various sources, including traditional telnet clusters, the Reverse Beacon Network (RBN), and PSK Reporter, providing a comprehensive view of band activity. The cluster's design emphasizes a user-friendly interface for monitoring DX activity across multiple bands, including dedicated support for JOTA (Jamboree On The Air) operations. Its aggregation capabilities allow operators to quickly identify propagation openings and active stations, streamlining the process of making two-way radio contacts. The integration of RBN and PSK Reporter data offers insights into propagation conditions and station reception reports, which can be invaluable for optimizing antenna direction and operating strategies.

WeatherExperts.Com, the premier online store for weather stations, instruments, anemometers, barometers, accesories, and satellite pictures. Excellent prices!

Sensitivity of multi turn receiving loops William E. Payne, N4YWK

Study of the Coaxial Dipole: Just how does this thing work.

WA0SXV article on the ICOM IC 756PRO based on his own experience

Pacific Division of the American Radio Relay League

tk7 is open source software designed for the ICOM IC-Q7 walkie-talkie. Though tk7 is intended chiefly for Linux, MacOS X, and BSD users, it will work on Microsoft Windows too.

Interface APRS to a weather station

A Few facts concerning GMT, UT, and the RGO

Layman level explanations of "seemingly" mysterious LF MF and HF propagation occurrences.

KD8KSB realization of the CJU satellite antenna that allow similar performance to the arrow antennas.

WR1B review of the Kenwood TS-570D on QST Jan 1997

Used in the Kenwood TM-241, TM-741 2m module by W3KKC