Search results

A 50 MHz stable and small power amplifier, suitable for portable and domestic use. This RF Power amplifier delivers 900W with used pair of tubes primary installed into amplifier.

In this article we share a useful and simple project to convert an unneeded car power cable to an Anderson PowerPole adapter.

This article documents the author's journey in building, modifying, and testing a DIY short vertical antenna for 40, 30, and 20 meters, with potential 80m capability. Initially inspired by Parks On The Air (POTA), the author explores pedestrian mobile operation and details various experiments to enhance antenna performance. The piece highlights challenges, SWR tuning, portability, and practical results, emphasizing a balance between efficiency and size. Ultimately, it showcases the adaptability of DIY antennas for portable ham radio applications.

By F2JD as HR5/F2JD from Copan Ruinas Honduras

Notes on installing the miniVNA PRO software, making a calibration standard, a trap tuning loop.

An International Educational and Scientific Organization Founded in August of 1952

The video showcases the setup of a 300 MHz oscillator, a 100W radiofrequency amplifier, and a dipole antenna for transmitting radio waves, leading to the fluorescence of a nearby light bulb. It demonstrates the presence of standing waves on the dipole antenna and how intensity varies along its length. Additionally, the usage of a copper pipe as a receiving antenna is explored, showing changes in intensity depending on alignment and proximity to the transmitter. Finally, a B field antenna sensitive to magnetic fields is introduced, revealing brightness variations in different orientations. The video offers insightful observations on radio wave transmission and reception phenomena.

An original amateur radio blog in Esperanto lenguage, all about ham radio, DX, antenna.

Risca and District Amateur Radio Society Tredegar Terrace Risca Nr Newport

A comparison among a traditional J-Pole Antenna and 2BCX Slim Jim Antenna

DX Pedition to Togo 2013

Representing the interests of Amateur Radio in Berkshire & the Thames Valley since 1934

An event to promote HF operation from the unique Hawaii destination in the Pacific.

This page by Keith Greiner describes a magnetic loop antenna project, providing step-by-step instructions to create two versions of a system with one large loop and one small loop. It includes details on how to construct the loops using different materials, along with the necessary equipment like antenna analyzers, tuners, and software. The page is divided into five sections covering project discussion, design summary, an improved small loop, construction steps, and radiation pattern analysis. Aimed at hams interested in building their own magnetic loop antennas, the page offers practical guidance and insights into impedance matching for improved performance.

New and information for the UK Radio Scout

A simple and cheap solution to monitor temperature of your repeater implementing a Raspberry Pi device with a set of popular tools made in python a database and RRD tool

Livingston amateur radio club site

Vanuatu YJ0X, DX pedition 3-14 October 2014

Explains the fundamental purpose of a repeater, detailing how these automated relay stations overcome distance and terrain limitations for VHF/UHF communications. It traces the historical development from early Bell Telephone Labs "relay" stations in 1922 to Art Gentry, W6MEP's, pioneering K6MYK amateur radio repeater in the mid-1950s, which remains active today. The resource clarifies the distinction between simplex and duplex operation, including the unique function of a "parrot repeater" for single-frequency recording and playback. Delving into the internal workings, the guide breaks down a repeater into its core components: the antenna system, feedline (often _Heliax_ or hardline for minimal loss), duplexer, receiver, transmitter, and controller. It emphasizes the critical role of the duplexer in preventing receiver desensitization by isolating transmit and receive signals, even with distinct frequencies. The discussion highlights the importance of high-performance, durable antennas and low-loss feedlines, citing examples of equipment installed in the 1960s and 1970s that are still in perfect working order. Operating a repeater is also covered, with an explanation of frequency offset (e.g., the 600 kHz standard for 2 meters) and the function of _CTCSS_ (PL tone) for access. It outlines standard input/output offsets for various bands, from 6 meters to 23 centimeters, while noting regional variations. The guide also touches on features like autopatch and Digital Voice Recorders (DVRs), providing a solid foundation for understanding repeater technology and usage.

This page provides a fully customizable band plan. You can easily customize the frequency limits, scale, define custom windows for modes and activities, adding or removing bands. You can tehn Export to PDF or print the bandplan to distribute the document to help hams operating within the designated spectrum efficiently. Useful for both new and experienced hams looking to produce their custom bandplan.

RDF Equipment Ideas for VHF Foxhunting and Radio-Orienteering. This information is primarily for the Amateur Radio two-meter band

If your multiple transceiver station is suffering of intrastation interference, this handy and inexpensive band pass filters and help you. QST article Sept 1988

BktRemote Suite is a package of programs that allow you to control the transceiver with different devices via a LAN connection or WiFi. The whole suite is composed by BktRemoteServer and BktRemoteClient

The Swiss army knife for Digital Voice, the DVMEGA radio is basically a complete D-Star and DMR compatible hotspot

These frequencies have been adopted into the bandplans of each IARU region to be a focus for emergency communications in their areas. They are not absolute frequencies but instead are centres of activity and emergency communications may be found around 20kHz from these centres. Some countries may maintain other emergency frequencies in their own bandplans due to local requirements, QRM etc

GB3SO GB3FR Official Fenland Repeater Group website

Mounting on roof at the right ground level can greately impact on antenna performances because will affect the radiated angle of energy.

NearSys (Near Space Systems) is a multifaceted organization, with interests in near space exploration, microcontrollers, robotics, space, and astronomy. Includes a section dedicsated to Amateur Radio High Altitude Ballooning

The parallel lines contest group - g4lip/p

This is an uncommon loop antenna, hombrewed without the small feeding loop. With small spare parts is possible to build a loop antenna tuner for portable usage tha can ben used with common HF QRP transceivers

This page presents an online calculator tool for determining the dimensions of various HF wire antennas operating between 1.8-30 MHz. Users input their desired resonant frequency to obtain precise measurements for four popular antenna types: standard flat-top dipole, inverted Vee, quad loop, and equilateral delta loop. The calculator provides comprehensive measurements including leg lengths, minimum heights, horizontal spreads, and feedpoint distances. Accompanying the calculator are detailed technical explanations, construction notes, and installation guidelines for each antenna type, making it a practical resource for amateur radio operators building their own antennas.

A homebrew 13 elements yagi antenna for two meters band. These project includes two model of the same antenna with a 6 and 7 meter boom length. Detailed pictures and nec files are available for download

This article introduces an Arduino-based QRP CW Transceiver designed for lower HF bands. The journey begins with the Wotduino, evolving from a keyer to a multi-mode beacon. The development includes a QRP transmitter and culminates in a receiver inspired by Roy Lewallen design. The transceiver, controlled through a control bus features a signal path, modulation, filtering, and adjustable frequency settings. Despite initial testing intentions, successful QSOs on 80 and 40 meters showcase its functional capabilities.

A project for a 5-over-5 stack on 10 meters

This blog post details the construction and usage of a 4:1 current balun, using two FT240-31 ferrite cores and 12 bifilar turns. It clarifies common misconceptions about using 4:1 baluns with G5RV antennas and ladder-line to coaxial cable connections. M0PZT emphasizes the importance of proper measurements and the limitations of internal baluns in manual antenna tuners. Detailed instructions and considerations for winding and deploying the balun are provided, along with advice on choosing suitable cores and wire for various power levels and frequency ranges.

H44MS is call of DL2GAC during DX vacations in Solomon Islands 1.Febr. to 30.April 2015

A gallery of home made capacitors made with ALU clamping plates and teflon insultators

This review of progress and future Prospects provides a practical guide for effective use of VHF sporadic-E propagation.

The Washington County Amateur Radio Club (WCARC) was formally established on June 26, 2014, serving amateur radio operators and enthusiasts in Washington County, Texas. The club provides a local community for hams to gather, share knowledge, and participate in various radio activities. Its formation date indicates a relatively recent establishment within the amateur radio landscape. The WCARC aims to foster interest in amateur radio, offering a welcoming environment for both licensed operators and individuals new to the hobby. Membership is open to anyone with an interest in amateur radio, promoting engagement across different experience levels. The club's activities likely include regular meetings, field operations, and support for emergency communications within the local area.

2E0RDj Amateur Radio Station in Beachley, Nr Chepstow. IO81QP. Projects, Radio & Weather.

A polarity checker is a very useful item to have around the shack and in a go-kit. This project, inspired by a QST article on powerpole connector protection illustrate how to build a polarity checker.

Large collection of 1900's antique Radios for sale,Floor model, Cathedral, table top, Novelty, Battery, police and broadcast band image gallery

Associacao de Radioamadores da Vila de Moscavide Portugal

Learn how to build a simple 12vdc azimuth and elevation motor unit for the Arrow Satellite Antenna to improve your FM satellite communication experience. This DIY project involves using a camera tripod and basic materials like aluminum tube and standoffs. Get detailed instructions, including the gearhead motor product number for optimal performance. Discover where to purchase the necessary components and stay updated on alternative motor options. Enhance your ham radio operations with this homemade rotator setup, designed for easy satellite tracking and communication. Share feedback and connect with other radio enthusiasts for more tips and ideas.

A website with a large collection of world flags pictures in GIF format divided per continent. Includes flags of US and Canada states

Three cell Lipo batteries for the FT-817 work really well, although not really sure about taking them on aircraft. The Lipos intended for use on RC Electric airplanes generally have a very low internal resistance and no internal protection against short circuit.

A complete set of pages about the Yaesu FTDX3000 Yaesu transceiver, including USB Driver informations, voice keyer details, complete menu group informations, remote control and CAT control program, SDR Play and FTDX3000 configuration, firmware links and manuals

SPARC The Saltlake Peaks Amateur Radio Club, founded by employees of L-3 Communications located in Salt Lake City, Utah at the Communications Systems West Division.

The Eagle Radio Group Mablethorpe England United Kingdom

MRRC is a club of amateur radio operators who are interested in on-the-air radio competition