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An Hentenna project for the six meters band. The standard size of standard hentenna is width 1/6 wavelength x height 1/2. The antenna build in this project is a full wavelenght antenna for the 50 MHz providing a 6.8 dbi gain.

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.

High Speed Multimedia (HSMM) radio, as introduced by John Champa, K8OCL, represents a significant advancement in amateur radio's digital capabilities, moving beyond traditional keyboard modes like packet radio. This initiative, driven by ARRL's Technology Task Force, focuses on developing high-speed digital radio networks capable of up to 20 megabits per second. HSMM primarily facilitates digital voice (DV) and digital video (ADV), enabling real-time video transmission from emergency scenes to an EOC without expensive ATV gear, often requiring only a laptop, a PCMCIA card, a digital camera, and a small antenna. The working group's initial efforts concentrate on cultivating microwave skills within the amateur community to build and support portable and fixed high-speed radio-based local networking, or **RLANs**. These networks prove invaluable for RACES and ARES organizations, as well as homeland security and other emergency communications. Field Day exercises and simulated emergency tests (SETs) are encouraged to hone skills in rapid site surveys and deploying broadband HSMM microwave radio networks, with examples like linking Field Day logging stations or antenna test results at the Midwest VHF-UHF Society Picnic 2003. Getting started with HSMM often involves adapting off-the-shelf **IEEE 802.11** (WiFi) equipment to comply with amateur radio regulations, typically operating in the 2.4 GHz ISM bands. While consumer WiFi gear has range limitations under Part 15 rules, proper setup under amateur regulations can extend coverage significantly, with test networks like the Hinternet achieving 5-15 mile ranges at 54 M bit/s using small mast-mounted dish antennas. Careful selection of equipment with external antenna ports, high transmit power, and low receive sensitivity is crucial, along with using low-loss coaxial cable like LMR-400 for optimal performance at these frequencies.

MARCA, Inc. operates approximately 24 repeaters across Arizona mountaintops and Phoenix-area rooftops, supporting modes like D-STAR and Fusion. The club, holding the **W7MOT** callsign, engages in diverse activities including ARRL Field Day events near Forest Lakes, AZ, ARRL FMT contests, and antenna experimentation. Members actively participate in HF operations such as voice, digital, CW, DXing, and various digital HF modes, alongside MESH and EOC operations within the valley. The club's interests span a broad technical spectrum, from SDR radio building to antique radio restoration, and include modern digital modes like WSPR, WSJT, FT8, and FT4. They also explore computer-based operations such as Echolink, fostering a dedicated Single Board Computer (SBC) and Raspberry Pi group. Monthly VE testing sessions for Technician, General, and Extra Class licenses are conducted by Ray Vasquez, K4RMV. Meetings are held on the third Tuesday of each month, typically lasting two hours, with a business segment followed by a technical presentation. These gatherings occur in-person at IHop in Mesa, AZ, and concurrently via Zoom, accommodating both local members and winter visitors. Informal chat groups often form post-meeting to discuss specialized topics like D-STAR, SDR, APRS, MESH, and Fusion.

The BikeLoop antenna project details the construction of a double magnetic loop antenna optimized for VLF frequencies, specifically around 136 kHz. This innovative design incorporates two orthogonal loops, which significantly enhance reception capabilities. Key construction hints include utilizing lightweight bicycle rims for the antenna structure, making it easy to transport and set up in various locations. The document provides valuable mathematical and electrical insights into the antenna's performance, alongside practical reception tests conducted in the Italian Alps, showcasing its effectiveness in capturing various VLF signals, including Sferics and FSK transmissions. Proper setup is crucial for optimal performance. The project emphasizes the importance of grounding and avoiding interference from nearby electrical sources. The reception tests revealed the antenna's ability to capture a range of signals, demonstrating its practical application for enthusiasts interested in VLF reception and antenna experimentation. Overall, the BikeLoop serves as an excellent starting point for those looking to explore the world of VLF frequencies and enhance their antenna-building skills.

You can upload your adif-file It then checks the qso for specified band and if a maidenhead locator is specified. It then builds an array and plot a graph.

This article include a circuit that allows a cheap 0-1mA meter to be used as a micro-ammeter or a milli-voltmeter

Wireless Society of Southern Maine Projects, instructions and photos for many ham radio projects and experiments, including antenna construction and modelling, kit building, station setup, restoration and more

This article demonstrate how to build and mount a 40 meter loaded dipole using basic materials. This antenna reduce the overall length of an HF dipole through the use of loading coils.

A balun is a MUST for dipoles or similar antennas when they are feed with coaxial cable. From the RF point of view, the shield can be modeled as two conductors, the internal shield (the real shield, this is, ground) and the external shield, who is really far to be ground. In this way, your dipole has 3 arms, the two from the dipole and the coaxial cable shield (external face)

Building A Full-Wave Quad Loop Antenna for 6 Meters. This is an easy antenna to build and the materials cost about $15-20. It exhibits 1.8dB gain over a 1/2-wave dipole. Using an open-wire parallel feedline (commonly called ladder line) with an antenna tuner, it tunes up on the 10m band as a 5/8-wave loop as well

This article provides details on building a 6 Meter J-Pole antenna using PVC pipe for an enclosure. This antenna uses flat 450 ohm Window Line for the tuning stub.

The build was an experiment to see if a tube receiver could be stable enough to receive digital shortwave radio broadcasts. The tube acts as both an oscillator and mixer, so the receiver is a type of direct conversion receiver.

How to build a Simplified Arduino CW Trainer, this is a version that does not need a keyboard.

For my SOTA activities, i recently bought a QRP transceiver QRP SW-3B, which is a three-band QRP CW only for 40/30/20 m. So, i needed an antenna that would allow to use these 3 bands in SOTA portable activity. Already having some experience with the EFHW antenna, i decided to build one for 40/30/20m.

256 memories enable the _AT-AUTO_ to recall settings across multiple bands, making it efficient for operators who frequently change frequencies. The tuner is compatible with various antennas and amplifiers, such as the Mercury LUX, and integrates seamlessly with radios like the FLEX 6400 using an RS232-USB connection. This integration allows the tuner to follow frequency changes without additional input, enhancing operational efficiency. Despite being out of production, the _AT-AUTO_ remains supported by Kessler Engineering, which offers firmware updates and repair services. The tuner features a cross-needle SWR meter, providing quick visual feedback during tuning. It also includes a QRO keyline circuit to protect amplifiers during tuning. Users appreciate the tuner's ability to track radios via CAT control, avoiding automatic tuning during QSOs, a common issue with other models. The _AT-AUTO_ is praised for its durability and performance, with many users noting its reliability over years of use. Its ability to handle legal limit power and its balanced line output make it a versatile choice for serious operators. Although it lacks some features like multiple coax outputs found in other models, its robust build and continued support make it a valuable tool for HF enthusiasts.

I used a FT 240-43 for much more power, not needed but beter safe than sorry. 150 Watt continious, 300 Watt PEP SSB, 90 Watt Digimodes 10 Mhz, 18 Mhz, 24 Mhz Very easy to build design and a good antenna for people who don't have much space for big towers or long wires This design is from Hans - PE1RNU

But it is only a couple of dB, The Effect Of Insertion Loss On Transmitted Power (dB to percentual loss) Original Information Provided by Neil McKie WA6KLA

This type of antenna is a popular antenna design as the performance is very good across the HF bands and requires little or no tuning. It’s a dipole fed off center with a 4:1 balun at the offset feed point. The antenna shown covers 80, 40, 20 and 10 meters. The formula can also be used to adjust the overall length to cover more or fewer bands and the resulting overall length. 160-10m, 80-10m or 40-10 meters depending on your available space. Other bands will require a tuner.

A light portable 2 element Delta beam antenna for 14 MHz. It is basically a two element delta loop wire antenna made for portable usage providing good directivity and a 4.2 dBd gain

This page describes an update to a project for a Power and SWR Meter for ham radio operators. The update includes a more powerful microcontroller, increased sampling rate, and improved display options. It explains how to use the new components and provides detailed instructions for building the updated meter. The page also offers alternative display options and includes the full source code for the firmware. Overall, this update enhances the functionality and performance of the Power and SWR Meter project, making it more versatile and user-friendly for hams looking to measure RF power and SWR in their radio setups.

Schematic diagram circuit to build a RS232 serial interface for the Yaesu FT 1000D, works also as CW Keyer control with Log-EQF software. May be used with other Yaesu HF Transceivers.

A 3 band dipole antenna for 40-80-160 meter bands, It's made with easily available materials and is designed for inverted V mounting. The antenna is shortened for these bands, but still manages to make contacts in 80m and 160m with stations in Canada and the USA. The construction details are provided, including the dimensions of the antenna elements and the traps. The antenna is easy to build and provides good performance in all three bands. In Italian.

This page details my building of a 100 Watt Power Amplifier for the 432 MHz Band based on two Motorola MRF646 transistors taking inspiration by Carlo Gnaccarini VK3PY, formerly VK3BRZ

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.

The MiniPA Linear Amplifier for HF page discusses the popularity of QRP for HF among ham radio operators, such as those using the Yaesu FT818 or low power SDR transceivers. It explores the use of cheap kits from eBay or Chinese suppliers to build a 70-100W SSB amplifier using IRF530 MOSFET transistors. The article provides a review of the MiniPA design, including its features, components, and assembly process. It also highlights the importance of using a heatsink and forced air cooling for optimal performance. This page is useful for hams looking to enhance their HF rig with a budget-friendly amplifier.

Jeri Ellsworthhas started a video series devoted to building a magnetic loop antenna for the 160- and 80-meter bands. The first video, included after the break, is an overview of the rationale behind a magnetic loop

DL7JV shares his practical experience building and testing capacitive antennas, initially skeptical of their performance compared to magnetic loops and mono-band dipoles. His interest was piqued after hearing a Spanish station running 100 Watts on 80 meters with a 1-meter Micro Vert, making DX contacts into PY and UA0, despite the antenna being only 4 meters high in a garden. This prompted DL7JV to investigate further, consulting resources from DL7PE and DL7AHW, the latter providing DOS programs like "Mitspule.exe" and "Spulenprg.zip" for calculating antenna dimensions and coil conversions. The article outlines the construction of two prototype antennas: one for 7.050 MHz using a 75mm PVC pipe and another for 3.550 MHz with a 110mm PVC pipe. Both designs feature aluminum foil condensers and coils wound from 1mm² H07V-K wire. DL7JV provides specific measurements for the condenser capacitance, surface area, diameter, height, coil inductance, turns, and wire length for both 40m and 80m versions, along with RG58 feedline lengths. Initial reception tests for the 7 MHz antenna, placed indoors, yielded impressive S9+5 signals from a German station compared to an S8 from a 42-meter roof-mounted loop, even hearing a Japanese station. Transmission attempts on April 4, 2004, despite moderate solar storm conditions, resulted in successful QSOs on 7 MHz with EA5OT (579/559) and on 3.5 MHz with YT1NT (579/559) and G4KKI (579/559) using 100 Watts. DL7JV notes the antenna's sensitivity to coordination and feedline layout, suggesting a modification from DL7AXO involving a 500pF fixed capacitor and coil tap for improved SWR stability. He concludes that while the capacitive antenna is space-saving and performs well for reception and 100W transmission indoors, its transmit performance doesn't yet match larger antennas, with further outdoor field tests planned. DL7JV also intends to build a 1.8 MHz version.

This PDF guide provides step-by-step instructions on how to build a Bunnings Balun for your ham radio antenna. A balun is essential for matching the impedance between your antenna and radio, improving signal transmission. The guide is perfect for hams looking to enhance their radio setup on a budget. Follow the detailed instructions to create your own balun using easily accessible materials from Bunnings or any hardware store.

If you want to build your own common mode choke, this article explains how to measure the efficiecy of your choke before using it. In the examples has been used Amidon FT240-31 toroids.

Demonstrates the activities and mission of ARMIC, the Association of Visually Impaired and Disabled Radio Amateurs of Catalonia, operating under the callsign EA3RKR. The organization focuses on making amateur radio accessible to all, particularly those with visual impairments, by providing resources and fostering a supportive community. It highlights their commitment to inclusive radio operation within the amateur radio service. ARMIC's initiatives include an accessible radio school, emphasizing practical construction projects and operational techniques tailored for members. The association actively promotes participation in various amateur radio activities, ensuring that visually impaired operators can engage fully with the hobby. Their work underscores the importance of adaptive technologies and methods to overcome physical barriers in radio communication. This resource reflects ARMIC's dedication to building an accessible radio environment, aligning with the broader goals of the Grupo Social ONCE, a Spanish organization supporting blind and visually impaired individuals.

The 20-10 meter fan dipole antenna described here offers broadside East/West coverage, a characteristic I've found particularly useful for working DX across the Atlantic and Pacific from my QTH. This design connects multiple dipoles of varying lengths in parallel at a single feedpoint, enabling operation across 20, 17, 15, 12, and 10 meters without the need for an external antenna tuner or switching. The guide specifies element lengths for each band, constructed using 1/2 inch PVC pipe for the elements and a 2-inch PVC pipe for the 8-inch long feedpoint connector, ensuring a robust build. Key advantages highlighted include its multi-band coverage, simplified installation, cost-effectiveness, and improved efficiency compared to single-band alternatives. The antenna is horizontally polarized when deployed at a height of 50 feet, providing a favorable radiation pattern for long-haul contacts. Materials required are readily available, including PVC pipes, _RG-8X_ feedline, antenna wire, and guying rope, making it an accessible project for most hams. This _fan dipole_ project provides practical considerations for construction and tuning, aiming for optimal SWR performance across the target bands. The detailed instructions, coupled with the specified components, allow for a straightforward build, even for those with limited antenna building experience, yielding a capable HF antenna for the upper bands.

The goal of this interesting project is to monitor a particular set of frequencies for a set period of time. In this article your will find instructions to build and operate an all-band WSPR node using cheap hardware and free software. At the end of this you'll have a Raspberry Pi, connected to an RTL-SDR dongle that monitors all of the WSPR frequencies rotating randomly every 15 minutes.

An L-Match tuner is a device that can add either inductance (L) or capacitance (C) to the antenna, bridging that gap between 5000 ohms and 50 ohms, thus matching it to the radio. The L-Match tuner is an extremely useful device that every QRP operator will want to have.

The QMX+ Transceiver Kit from QRP Labs is a high-performance, feature-packed 160-6m 5W transceiver designed for hams. This multi-mode kit includes embedded SDR, USB sound card, CAT control, synthesized VFO, RTC, and optional internal GPS. It can be used in CW, digital, and SSB modes, with standalone CW operation, digi mode via USB to PC, or SSB operation. The kit offers standalone beacon functionality and shares firmware with the QMX model. With an optional enclosure, battery-backed RTC, and GPS, the QMX+ is versatile and easy to build, making it ideal for ham radio operators looking for a customizable transceiver kit.

This article shares the author's experience with building antennas. After putting a large magnetic loop project on hold, they decided to try a base-loaded vertical antenna. The author explains how they chose to design a new antenna from scratch, aiming for a frequency of 7 MHz. They describe the calculations needed to find the right coil inductance and how they used 3D-printed parts for the construction. The article wraps up with results from their initial tests, showing good communication on different bands and highlighting the success of their design.

A 3.5–24 MHz regenerative receiver for amateur bands was recently constructed, inspired by a 1934 design. The project was both challenging and rewarding, requiring precise tuning and high-quality components. The receiver successfully captured QSOs from across the globe, such as New Zealand communicating with Panama. The simplicity of the design and the satisfaction of building a functional, compact wooden box with handmade resonant circuits were highlights. This project demonstrates a meaningful way to reconnect with the roots of amateur radio.

This article describes a multi-band antenna design for amateur radio enthusiasts by G3FEW. The antenna is designed to cover at least five HF bands with low SWR and without the need for an ATU. It is also designed to be easy to construct and adaptable for different locations. The antenna is a full-wave dipole with traps at the quarter-wave points. The traps are used to tune the antenna to different bands. The antenna can be fed with a 4:1 balun. The article includes instructions for building the antenna, as well as information on the theory behind its operation. The author also discusses the results of his tests with the antenna. This multi-band antenna is a well-designed and versatile antenna that can be used by amateur radio enthusiasts on a variety of bands. It is relatively easy to construct and can be adapted for different locations.

This page offers an online antenna designer tool for Hams to calculate the dimensions needed to construct a coaxial collinear antenna for a specific frequency. It provides guidance on the required frequency input, coax velocity factor, and element measurements for optimal performance. The tool is recommended for experienced antenna builders due to its complexity and technical requirements. Users can input the frequency in MHz and the tool will generate the necessary dimensions based on the chosen parameters. The page emphasizes the importance of accurate measurements and connections for successful antenna construction.

This article provides a step-by-step guide for assembling a Raspberry Pi-based Satellite Tracker Interface, designed to work with Green Heron Engineering's RT-21 controllers and MacDoppler software. The guide covers hardware assembly, SD card image installation, and system configuration for satellite tracking.

Learn how to easily build a 10-meter vertical antenna, perfect for DX contacts on the amateur radio bands. This flowerpot or T2LT design is portable, efficient, and ideal for ham radio operators looking to improve their DX performance. With just a few basic tools and materials, you can construct this antenna for portable operations or as a home station setup. Discover how to set up the antenna, improve its performance by raising it higher, and start making contacts with stations around the world. Watch a step-by-step guide on YouTube for building and testing this DIY ham radio antenna.

Constructing a directional antenna for VHF operations, particularly for 2-meter band contests or local communication, often involves balancing performance with ease of build. The Moxon rectangle, a compact two-element beam, offers a good front-to-back ratio and gain in a smaller footprint compared to a Yagi, making it suitable for portable or temporary setups where space is limited. This design typically uses a driven element and a single reflector, bent into a rectangular shape to achieve its unique radiation pattern. The article details the construction of a 2-meter Moxon antenna, specifically for 144 MHz, utilizing readily available materials like PVC pipe for the frame and copper wire for the elements. It outlines the dimensions for the driven element at 970mm and the reflector at 910mm, with a spacing of 140mm between them, and a 50mm gap at the element ends. The feedpoint is a direct 50-ohm connection, simplifying matching requirements. The project includes a parts list, a basic diagram illustrating the element layout and dimensions, and photographs of the completed antenna. The author notes the antenna's performance during a QRP contest, achieving contacts up to 100km with 5 watts, demonstrating its effectiveness for low-power VHF work.

Two easy to build microcontroller projects for machine recognition of hand-sent morse code

This page describes a couple of parts box medicine bottle antennas that you can build. The ground side of the capacitor is soldered to the ground of the BNC connector. The positive side of the capacitor takes 5 turns around the toroid and is soldered back to itself. The center pin of the BNC connector takes 5 turns around the toroid and then continues on to the wire wound inductor. From there the antenna continues with an attached piece of wire.

Illustrates the fundamental principles of radio repeaters, detailing their role in extending communication range beyond line-of-sight limitations. It begins by defining _simplex communication_ as a direct radio-to-radio link, effective only when no obstructions impede the signal path. The resource then introduces the concept of a repeater (or base station) strategically positioned on elevated terrain, such as a mountain, to overcome geographical barriers. The article clarifies the repeater's operational mechanism: it receives a signal on one frequency and simultaneously re-transmits it on a different frequency, enabling users on opposite sides of an obstruction to communicate. This _duplex operation_ is likened to satellite communication for VHF propagation, but with a fixed terrestrial station. Specific examples of signal paths are provided, showing how a handheld radio transmits up to the repeater, which then relays the message down to another user, effectively bypassing obstacles like hills or large buildings.

Analysis, design and construction of a simple & useful SWR meter from yesteryear! Schematic diagram, pictures and instructions to build a Monimatch style SWR Meter

The PAC-12 Antenna, a multi-band portable vertical, is meticulously detailed in this construction article by James Bennett, _KA5DVS_. The design emphasizes ease of homebrewing using readily available components from local hardware stores, including replaceable loading coils. It outlines the preparation of the 72-inch telescoping whip (originally from Radio Shack, with an alternate source now provided by _Pacific Antenna_), the construction of the loading coils from PVC risers, and the fabrication of the aluminum rod base sections. Specific instructions cover threading aluminum rod with a _1/4-20 threading die_ and assembling the feedpoint insulator with a BNC connector, along with recommendations for radial deployment. KA5DVS, an avid traveler and QRP enthusiast, developed the PAC-12 to address the bulkiness of random wire setups and the limitations of commercial portable antennas like the Outbacker or SuperAntennas MP1. His goal was a lightweight, packable antenna that disassembles into 12-inch sections, achieving an assembled length of approximately 8 feet. The design strategically places the loading coil away from the base for improved efficiency. The PAC-12 notably placed first in efficiency compared to a quarter-wavelength wire vertical at the HFPack antenna shootout during the Pacificon conference in October 2001, demonstrating its practical performance for field operations. Appendix C showcases various _NJQRP Club_ members' PAC-12 constructions, including a 20m beam made with multiple PAC-12 elements.

An optocoupled audio interface between PC and Transceiver for digital modes. The article includes full schematic of complete board and build instructions.

Homebrewing a UHF antenna to be used on a bicycle. This simple project gives you the right hints on how to build and setup and install a 70cm antenna on a bicycle.

Send and receive wireless messages adding a small 433MHz radio to your Raspberry Pi, without the need of a WiFi connection and operate remote-control main sockets