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OH7UG QSO blog from Finland

Personal Page UR4IOR from Ukraine, with some nice personal photos.

Inventor of the Beverage antenna

An interesting review of the Icom 2720H VHF UHF amateur radio mobile transceiver with pros and cons

List of countries that have been worked from the Czech Republic on 50 MHz band since January 1, 1993

Description of an HF beacon keyer with telemetry. What makes the keyer rather different is its versatility - it is a multi-mode unit, with ASK and FSK modulation, sending Feld-Hell and Morse on command

The Laurel Highlands VHF Society, Inc. owns and operates the Acme repeater, located on the Chestnut Ridge in southwestern Pennsylvania.

Big Rapids is located in central Michigan and is home to about 11,000. Big Rapids is also home to Ferris State University and the Big Rapids Area Amateur Radio Club

This software loads WPX type ADIF files with the <PFX:xxx> tag and calculates the different callsign prefixes. The software will load and capture the totals for big files. ADIF files must have the .adi file extension.

This freeware application for Linux and windows, allows you to convert an ADIF file to a KML file so you can map your QSOs easily and open it with google maps, or google earth or any application supporting the KML format

Hamradio, Webcams, Radio and TV-Links by DF3SP Walter

Launch of a hybrid rocket from high altitude by untsville Alabama L5 Society

Plymouth Historical Museum radio station

The Triple H Net Association Net

OK2ZC ex ok2bee homepage with log search and photos

Ham radio club in west Los Angeles

A small, easy to build, copper tube magnetic loop antenna for the 2 meters band. In Italian

DX resources by SV1CNS

Official web site of the yt9x contest team Radio Club "Sevojno" - YT9X Contest Team

28,227.5 MHz, from JN55VF first "IW" prefix beacon "ON THE AIR" activated from Italy

Using RadioMobile to evaluate Meteor Scatter DX-pedition sites

Personal blog dedicated to mobile amateur radio operations

Provide communication service primarily to the public safety organizations

The Tri-pole antenna, a clever modification of a standard dipole, allows for dual-band operation by integrating a third element. This design effectively shortens the overall dipole length by 10 to 20 percent, simplifying antenna rotation and offering a compact footprint. KK4OBI's article delves into the operational principles, using a 6 and 10-meter Tri-pole as a primary example, and provides comprehensive instructions for constructing any Tri-pole antenna within the 6 to 15-meter range. Key to the Tri-pole's performance is its off-center feed, necessitating a common mode choke at the feed point for optimal tuning and reduced noise. The author outlines a methodical approach to determining element dimensions, starting with a vertical element frequency calculated as 0.47 times the sum of the desired upper and lower band frequencies. This calculation, along with K-values derived from trend lines, guides the initial lengths for the horizontal arms, demonstrating how a 10m-6m Tri-pole can achieve a total horizontal length 78% shorter than a conventional 10-meter dipole. Tuning and balancing are critical, with the article detailing adjustments to arm lengths and the vertical element to achieve balanced SWR values, as validated through 4NEC2 simulations. Radiation patterns are analyzed at various elevations, showing gains around 5.7 dBi and favorable take-off angles for DX contacts. Construction details specify aluminum tubing dimensions, U-bolts, and an SO-239 connector, emphasizing the importance of a ferrite-based choke for wideband operation.

On-line shop for coax cables, RF connectors, Lightning protectors, Create antenna rotators, antenna masts and mounts, amateur antennas by FlexaYagi, Tonna F9FT, ANjo-Antennen and M2 Antennas based in Eggolsheim Germany

Northern Tasmania Amateur Radio Club

TX on 28.289MHz since 1992

Network Analyzer on an Arduino Shield which covers from 0-72MHz using an Analog Devices AD9851 DDS chip

Stacking yagi antennas for 50 Mhz band article by by Zaba, OH1ZAA/NN0Y

An article by CT1BOH about recording amateur radio contests. Recording contests is a great tool to detect problems and improve operating efficiency

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 **Luis Trenker Award** is an amateur radio operating award established by the Amateur Radio Club Ladinia to honor the director and author Luis Trenker from Val Gardena, South Tyrol, Italy. To qualify for the award, HF stations must achieve five confirmed QSOs with each of five specific Alpine countries: Italy (with specific prefixes like I1, IK1, I2, I3, IN3, IW3, IV3), France, Germany (with DOKs A, C, T, U), Switzerland or Liechtenstein, and Austria (with prefixes OE2, OE3, OE6, OE7, OE8, OE9). A single QSO with a member of the Amateur Radio Club Ladinia can substitute for the five required Italian QSOs, with members' QSL cards bearing a special rubber stamp. VHF/UHF stations have a simpler requirement, needing only one confirmed QSO with each of the five Alpine countries. SWL stations are eligible under the same conditions as transmitting stations. All contacts must be valid after April 12, 1990. Applicants must submit a list of contacts, certified by two OMs or a club, to the Amateur Radio Club Ladinia in Ortisei, South Tyrol, Italy. The award manager is IN3PGS Karlheinz, and the club official is IW3AQL Luca.

Project by N9SSA

TX on 28.265 from Pimento, IN

Demonstrates the practical application of APRS (Automatic Packet Reporting System) through the lens of HB9PVI's activities in Switzerland. It covers the system's core function of reporting geographical positions and telemetry data from various objects, including mobile stations, aircraft, and the ISS, distributed via packet radio and internet gateways. The resource highlights the routing paradigm shift introduced in April 2005, specifically the recommendation to use _WIDE1-1_ instead of RELAY and WIDE for digipeating to reduce duplicate packets. The page presents real-time maps displaying the positions of amateur radio stations in Switzerland and around Bern, updated every few minutes. It details specific callsigns like _HB9BA-2_ (HB9PVI's home QTH), _HB9BA-8_ (a weather station), and _HB9BA-4_ (a WIDE digipeater on Weissenstein mountain), providing context for their roles within the local APRS network. Links to track HB9PVI's mobile operations (_HB9PVI-9_) and handheld devices (_HB9PVI-15_, _HB9PVI-7_) are also provided. Furthermore, the resource curates a list of APRS software options for various operating systems, including _JavAPRS_ for Europe, _UI-view_, and _X-Astir_ for Linux, alongside digipeater/IGATE software like _DiXPRS_. It also offers downloadable APRS information, including a PDF article by HB9PVI and HE9ZGN, and a PowerPoint presentation in German, making it a repository of practical and historical APRS data.

Basic magnetic loop antenna examples and loop aerials theory explained. This article inclued some interesting tricks on building magnetic loop antennas and an usefull excell sheet to help compute magneti loop antennas calculating power efficiency from 10 to 40 meters band

The Chelsea Amateur Radio Club is based on service to the community and the advancement of Amateur Radio in Southeast Michigan.

Serving Hardin County Since 1969

Special Service Club

This resistor calculation tool shows which combinations of two resistors, series or parallel, gives a match better than the closest standard value.

SV1GRB's Homepage, photos from dx-peditions and useful links

Where abilities and disabilities become possibilities

Homepage of the belgian hamstation ON1DRS

A page with several testing and measurement resources usefull for those ham radio operators who needs to align or repair their own radio equipment.

Dxpedition to gabo island, australia, sept 2001 OC-196, ARLHS# aus-078, WLH No: 1031

The North Shore Amateur Radio Club, Branch 29 of the New Zealand Association of Radio Transmitters (NZART) is an incorporated society for Radio Amateurs and interested persons.