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This project is for those ham amateurs who do not have a commercial one . It's easy to build with a soldering iron, a plastic case and a little knowledge of arduino. The controller is made with budget components you can find easily in Internet. The main component is a cnc shield that fits over an Arduino Uno. Both made a compact, small and cheap controller.

An homebrew HF Magnetic loop made with 2m length of 6mm diameter copper pipe formed into a near circle as the low loss inductor, a short length of coax as a capacitor,a short length of mains cable, again as a fixed tuned capacitor, a tunable 365pF air spaced capacitor, and a small Jackson C804 airspaced variable with a small 3-35pF trimmer in parallel

This project explores the construction and performance of an Alford Loop antenna as an alternative to a round loop. The Alford Loop, symmetrically fed at opposite corners, behaves like a small loop despite its larger size. Built using PVC pipes and secured with tire wraps, the antenna integrates an LZ1AQ active amplifier for optimal performance. With deep nulls in its horizontal radiation pattern and improved resonance characteristics, this design has significantly outperformed previous active antennas in reception quality.

The document details the construction and performance of a rotatable flag antenna designed for a small lot. The 7x14 feet flag, built with fiberglass poles and an aluminum hub, shows improved reception compared to the author's previous transmit antenna. Key components include a conventional transformer for impedance matching and a variable resistance termination system to optimize performance. Despite challenges like nearby objects affecting signal patterns, the antenna consistently provides better signal-to-noise ratios, making it a valuable addition for low-band listening in suburban areas.

Spotty leverages Philip Gladstone’s pskreporter.info data, delivered via an MQTT broker by Tom Fanning (M0LTE), to offer a responsive web application for visualizing propagation. The Map View presents a default visualization (grid AA00 / callsign MY8CALL) and distinguishes signal types: small spots for signals heard by a location, large spots for transmissions from a location, and teardrop markers for transmissions from the monitored callsign. Clicking a spot reveals detailed signal data in an overlay. The application includes a Log View for raw spot data and a Settings tab for customization. Users can filter tracking by specific Callsign or Grid, with preferences saved to the browser. A notable feature is the Time to Live (TTL) setting, adjustable from the default 60 seconds, which controls spot visibility duration to manage map clutter during high-traffic periods. The tool provides a clear, logic-driven interface for real-time signal monitoring.

The "Beginner’s Guide to Small-station EME" by Paul Bock, K4MSG, offers an insightful look into Earth-Moon-Earth communication, a fascinating aspect of VHF and above amateur radio. This presentation demystifies moonbounce, explaining how two-way radio contacts are made by reflecting signals off the Moon. K4MSG highlights the historical context of EME, noting the substantial investment and technical challenges that once characterized these operations, often requiring setups like the W5UN "Mighty Big Array" (MBA). Historically, path loss exceeding 250 dB, spatial polarization offset, Faraday rotation, and galactic noise made EME a formidable pursuit, with CW being the mode of choice for signals that had to be audibly detectable. Equipment limitations in noise figure and coax performance further compounded the difficulty for early moonbouncers. However, the landscape of amateur EME dramatically shifted around 2003 with the introduction of the JT65 software. This innovation, specifically designed for EME, allowed for signal decoding well below the noise floor, making small-station EME a practical reality for more hams using common transceivers and less complex antenna systems.

This PDF document provides detailed information on small loop antennas for hams. It covers the design, construction, and usage of small loop antennas for amateur radio operators. The guide includes practical tips and recommendations for optimizing the performance of small loop antennas in various operating conditions. Whether you are a beginner or an experienced ham radio operator looking to improve your antenna setup, this guide has valuable insights to offer.

With some fantasy the circuit can be easily assembled on a small scrap of pre-perf board,and then fitted in the DB9 serial connector shell. The interface requires two NPN transistors and few more passive components.

Removing disturbing RFI from the Behringer HA400 Headphone Amplifier, using ferrites and capacitors soldered in the main circuit board of the small amplifier.

A small application for controlling the Elecraft K3

Learn how to build wire Yagi antennas for your ham radio setup. Discover how smaller wire elements can offer practical and portable options for temporary operations. Explore designs like the Hex Beam, Spider Beam, and Moxon that require less mechanical complexity and can be easily rotated or supported. Find out how to construct and hang wire Yagis from ropes, trees, or masts with inverted vees or horizontal elements. Get tips on element positioning, gain, and beamwidth considerations. Follow simple construction steps using a rope boom and marking element positions for efficient assembly. Enhance your ham radio experience with versatile wire Yagi antennas.

A 10-meter half-wave vertical antenna, designed by Thomas 4L/G8BAG, offers a practical solution for hams with limited space and materials. This "flower pot" design utilizes common hardware store items such as 60mm plastic drain pipes and 75 Ohm coax cable, demonstrating that effective HF operation doesn't require specialized components. The author details the coax preparation, including stripping the outer sleeve and braid at specific measurements like **2510 mm** and 2450 mm, and integrating it into the pipe structure. The construction emphasizes simplicity and low cost, providing an accessible path to getting on the air on the 10m band, especially when a horizontal beam is not feasible. The article notes an SWR of _1.5:1_ with 75 Ohm coax, managed by an MFJ 258 for impedance matching. This temporary solution proved robust, withstanding various weather conditions and achieving contacts across continents, including W, VK, BG, G, JA, and VR2, using 100W SSB from Georgia.

In his journey to improve Morse code skills, the author developed a straightforward device named the Tiny Keyer using Arduino. Tailored for Morse code enthusiasts and ham radio operators, this project utilized the budget-friendly Arduino ATTiny 85 Kickstarter board. With straightforward setup procedures in the Arduino IDE, the Tiny Keyer's small size and low cost make it accessible for beginners and hobbyist clubs interested in Morse code exploration.

The FT-991 is a nice small size and lightweight radio, it is perfect for portable operations. It can be carried along with a laptop computer as hand luggage in airplane. The weak point of this radio, is it does not have a separate RX antenna capability. Therefore i decided to add this feature. On the back side of the radio a BNC connector is added to connect the RX antenna and a switch is fitted to select between RX antenna or main antenna.

This article provides an in-depth review of the Ciro Mazzoni Baby Loop Ham Radio Antenna. The author, a ham radio operator, compares this magnetic loop antenna with his usual End Fed Half Wave antenna, discussing the performance and installation considerations. The post explains the concept of loop antennas, resonating frequencies, and the benefits of using a small loop antenna with a capacitor for optimal operation. If you are looking for information on magnetic loop antennas and their effectiveness in restricted spaces, this review offers valuable insights and practical experiences for ham radio operators.

CTR2-Mini is a small radio controller based on the Seeed Studios Wio Terminal. It can control many radios including FlexRadio 6000s. Multiple Minis can be used to control multiple slices on the Flex. It also has a special mode that allows two CTR2-Minis to control the Main and Sub VFOs on the FTdx101. An article on CTR2-Mini appears in the September 2022 issue of QST.

This article details the design and construction of a compact 20-meter QRP SSB transceiver by Pete Juliano, N6QW, measuring just 2 x 4 x 2 inches—small enough for a shirt pocket. Inspired by a 1963 QST design and refined from a prior version, it employs bilateral circuits, a 4.9152 MHz homebrew crystal filter, switched-crystal VXO for 60 kHz coverage (14.160-14.220 MHz), and standard components like ADE-1L mixers and IRF510 PA for 1W output. Key innovations include a double-sided PCB skeletal frame for shielding and isolation, Vectorboard sub-assemblies, and ultra-miniature relays. The bilateral receiver/transmitter shares stages, omitting AGC for simplicity, while a W3NQN LPF and optional 10W external amp enable DX contacts. Tune-up focuses on crystal matching and bias for linearity. Videos on YouTube demonstrate performance, confirming excellent stability and audio. Total cost nears $100, prioritizing portability over features like CW.

Sita is a small tool that permanently records an input of the sound card into the working memory and repeats the last 10 seconds if needed. This is ideal for connecting the radio to the Line In of the sound card and, if you have not understood something, to have the last 10 seconds repeated.

Attach a small right angle lug to the ground screw located in the rear of the FT-817 in order to make a more robust and stable power connection

The 1/4 wavelength vertical antenna project, initially designed for 20 meters, has evolved into a versatile portable solution covering 10 through 60 meters. K0BXB details its construction, emphasizing a bottom-loaded design with a tapped loading coil and four 10-foot counterpoise wires. The author shares personal experiences and field results, including **18 QSOs** during a park activation on 17m and 30m with 10 watts, and a **2,435-mile** contact with a contest station in Bonaire on 20m using 5 watts. Comparisons are drawn to commercial offerings like the _Wolf River Coils TIA_ and _QRPGuys Triband Vertical_, highlighting the DIY antenna's small footprint, light weight, and ease of tuning for POTA activations. The resource includes insights into using test equipment such as the _NanoVNA_ for SWR optimization and discusses various radiator lengths, from 17-foot wire to a 102-inch whip, demonstrating adaptability for different portable setups. Construction tips cover coil winding, tap placement, and connecting feedlines and radials using common components.

Chavdar Levkov, LZ1AQ, presents an experimental comparison of small wideband magnetic loops, building on his previous work on wideband active small magnetic loop antennas. His research focuses on increasing loop sensitivity by maximizing the short-circuit current, which is directly tied to the "loop factor" M = A/L, where A is the equivalent loop area and L is its inductance. Levkov's methodology involves reducing inductance and increasing area through parallel or coplanar crossed (CC) configurations, comparing these designs against a reference single quad loop of 1 m2 area. Experimental verification included testing three distinct loop types: a simple quad loop, two coplanar crossed (CC) loops, and eight parallel loops, all designed to have a total geometric area of 1 m2. Measurements were conducted at 1.8, 3.5, 7, and 10 MHz using a small transmitter 270 meters away, with a Perseus direct sampling receiver for precise signal level assessment. The results consistently showed that CC loops, particularly Loop 5 (two CC circular loops with 1.44 m2 total area), yielded significantly higher currents, up to 9.1 dB over the reference loop at 3.5 MHz, validating M as a reliable predictor of loop sensitivity. Numerical simulations using MMANA further corroborated the experimental findings, demonstrating an almost perfect correlation between the calculated M factor and the induced loop current for 15 different loop models. Levkov concludes that CC loops offer superior sensitivity for a given loop area, while parallel loops are advantageous for minimizing physical volume. Practical recommendations suggest using loops with an M factor greater than 0.5 uA/pT for quiet rural environments, and he provides a spreadsheet tool, WLoop_calc.xls, to aid in optimizing loop configurations for specific operational needs.

WB5NHL describes setting up a 160-meter antenna on a small suburban lot, where standard options like Beverage antennas and 1/4 wavelength verticals require extensive space and ground systems. Instead, Guy Olinger's Folded Counterpoise (FCP) provides a solution. The FCP minimizes ground losses by using a folded wire design, allowing effective antenna placement in limited space. The FCP, fed with an isolation transformer, enabled WB5NHL's first 160-meter antenna installation, offering improved performance despite space constraints.

Constructing a double bazooka antenna for the UHF band, specifically tuned for 435 MHz, involves a straightforward process detailed with step-by-step imagery. The design leverages readily available _RG213 coaxial cable_, cut to precise lengths derived from formulas: 140.208 / F (MHz) for the radiating element and 99.06 / F (MHz) for the coaxial section. This approach yields a highly effective vertical polarization antenna, suitable for local ragchewing or repeater access. My own field experience with similar coaxial designs confirms their robustness and ease of deployment. The article emphasizes critical steps like short-circuiting cable extremities, interrupting the braid at the center, and securing an insulating support. It also covers preparing the definitive mounting with a quality feedline, noting that RG58 is acceptable for temporary use but better options exist for permanent installations. Weatherproofing is crucial for longevity, achieved through PVC electrician's tube, glue, and heat-shrink tubing. The final assembly is designed for mounting on a small aluminum mast, with the feedline routed internally. The reported SWR measurement is very satisfactory, showing approximately **+/- 3%** HF return, indicating excellent impedance matching at the target frequency.

How to use a small USB DJ controller to remote control the Kenwood TS-590s

The small receiving loop (SRL) is a versatile and efficient antenna that can be simply built from common materials. It is designed for reception on the MF and HF bands and may be put in a variety of shapes and sizes. Despite its unusual installation, the porch loop in this case operated admirably, producing several DX spots on the 40m band. The SRL can be a great option for people looking to boost their reception on the MF and LF bands.

The article by Guy Olinger, K2AV, published in the May/June 2012 National Contest Journal, introduces the Folded Counterpoise (FCP), a compact 516-foot single-wire counterpoise elevated at 8 feet, designed for 160-meter operations on small lots like 100x150-foot backyards. Originating from efforts to revive Top Band for W0UCE on a postage-stamp property, the FCP uses strategic folds to cancel ground fields within 33 feet of center, minimizing losses to 0.13-0.53 dB—outperforming sparse or on-ground radials by up to 15 dB in poor soil—while mimicking opposed radials for efficient feedpoint impedance. Paired with a critical 1:1 or 4:1 isolation transformer (e.g., trifilar on T300-2 toroid) to block common-mode currents on coax feeds, it delivers proven results: K2AV's #8 North America low-power contest score, 7+ dB gains at W4KAZ and K5AF, and over 10,000 global web hits for DIY instructions using bare 12 AWG wire and weatherproof enclosures. Ideal for acreage-challenged hams, the FCP also excels on 80 meters with scaled dimensions, offering a low-loss alternative where full radials are impractical

Stampfl ham electronics produces SDR Receiver kits and Morse Keys in small batches and in the usual Swiss Quality

Noise-canceling electret condenser microphones (ECMs) are ideal for compact, battery-powered devices due to their small size, low power consumption, and high sensitivity. These microphones, used in conjunction with active noise cancellation circuitry, significantly reduce ambient noise, creating a more peaceful listening experience by combining and processing signals from multiple microphones.

A small windows utility to control VFO of the Yaesu FT-5000. It is capable to set frequencies for both VFOA abd VFOB. Tested with latest windows versions.

Learn how to easily convert between different units like dBu, dBm, W, mW, V, and uV with the dBCalc application. This small windows program allows ham radio operators to quickly check conversions using input and output resistance. It's a useful tool for anyone dealing with electronic measurements and calculations. Best of all, dBCalc is free to use, making it a convenient solution for amateur radio enthusiasts. This tool simplifies complex conversions and helps hams optimize their equipment setup.

AllScan is a free and open-source web app for AllStar nodes that provides Favorites Management features, AllStarLink Stats integration, and connection monitoring and control functions. Shows your favorites in a Dashboard summary table with Keyed status, Connected Node count and other statistics. Continually scans the status of each favorite using ASL's Stats API data showing which favorites are active and have recently been active. Allows favorites to be connected with a single click (optionally automatically disconnecting any currently connected nodes first). Allows the Favorites Table to be sorted by Node#, Name, Description, Location, etc. Favorites can be added/deleted simply by entering the node# and clicking a button. These features finally give AllStar nodes similar memory management and scan capabilities that analog radios have had for decades. AllScan is mobile-friendly and optimized for ease of use on both small and large screens. AllScan follows the latest web development standards, with PHP, JavaScript, HTML, and CSS cleanly partitioned, runs on both ASL and HamVOIP, and is very easy to install, configure, and update.

W1JR-style common mode chokes are versatile tools for antenna experimentation. Three variants were constructed using RK4 ferrite cores and RG303 Teflon coax, differing only in output terminals: banana connectors for dipoles, N-connectors for antennas with existing terminals, and bolts with washers for vertical antennas. Materials included junction boxes, terminals, and small hardware. Assembly involves maximizing windings on the core, securing with ties, and gluing components. Improvements included switching to multi-stranded wire for durability. These chokes provide efficient, customizable solutions for various antenna setups.

The Aziloop DF-72 antenna system provides 72 K9AY headings and 36 loop axes, allowing for rapid switching in 60 ms. It integrates a switchable 18 dB preamp, a 4-step attenuator (0-18 dB), and four 7-pole preselection filters to optimize receiver performance. The K9AY load is adjustable from 250 Ohm to 950 Ohm in 50 Ohm increments, offering flexibility for various receiving conditions. Control is managed via an intuitive Windows UI, supporting Local, Client, or Server modes, with headless remote operation possible through the built-in Ethernet Server. _Omni-Rig_ support facilitates auto-filter selection, PTT muting, and Rig-Sync functionality, enhancing integration with existing station setups. Designed by _GW4GTE_, the system utilizes a low visual impact, small-footprint antenna with orthogonal loops and an earth connection. It is suitable for general monitoring, co-channel station resolution, basic direction finding, and interference reduction across the VLF to HF spectrum.

If your FT-817 has stopped powering up from the internal battery but works from external power, then maybe the internal battery fuse has blown. There is a small PCB mounted fuse to protect the battery and radio. This fuse can blow, if it does your radio will not work from battery power. This page will describe how to test the fuse and describe how to make a repair.

The POCKET TUNER V1.1 is a highly compact HF T-Match antenna tuner designed for QRPp and QRP portable operations. With a credit card-sized form factor, it is tailored for low-power setups, supporting HF bands from 10m to 40m. The tuner features a unique design using rotary switches for precise capacitor adjustments, allowing tuning in small increments. Its inductance selection is optimized for various bands, ensuring efficient performance. Equipped with a resistive tuning indicator, it protects the transmitter by reducing SWR during adjustments. This versatile and portable tuner is ideal for field operations, enabling efficient antenna matching for low-power rigs.

Learn how an experienced ham radio operator designed and built a compact shack in their motor home. Discover the considerations, challenges, and solutions involved in setting up a radio station in a small space without damaging the vehicle. Find out which radios were chosen for VHF/UHF scanning, HF communications, and QRP operations. Get insights on cabinet design, speaker placement, and radio cabling for a functional and portable ham radio setup on the road.

A small Yagi antenna for camper van. It is made of aluminum tubing, breaks down for storage, and works well for communicating with others. He built it in an afternoon and it gets good signal. The antenna is lightweight and can be packed up to fit inside his van while traveling

The CW keyer with memories, inspired by SOTA activities, features three on-the-fly programmable memories for hands-free operation during logging or specific calls. Designed for low power consumption, it uses AAA batteries and an Arduino Mini, optimized for minimal energy use with a sleep function. The compact design fits in a small TEKO box, with a printed circuit board for easy assembly. The keyer includes customizable software for various CW modes and settings, programmable via paddles and command mode. It's an efficient, portable solution for amateur radio enthusiasts seeking enhanced CW functionality.

In this project by building a W2IMU feed horn, the author successfully optimized their 10GHz Small Dish EME project. To position and solder the components together, they used a jig and a conical section made of copper sheet. Stability was ensured by fitting the XLNA to the WG switch. The WG components were shod into a waterproof plastic container, and the feed horn and WG were surrounded by a collar and skirt that were 3D printed. With an average Moon noise of 0.5dB, the Sun and Moon noise readings were better than their previous configuration.

This page provides a detailed review and installation experience of a new 6 and 2 meter dual band Yagi antenna. The author shares insights on the purchase process, shipping, assembly, and performance of the antenna in their backyard setup. The content is useful for hams looking for information on dual band Yagi antennas, especially those interested in improving their contest operations or backyard installations. The author's personal experience and challenges with mounting the antenna on a small push-up mast are also discussed.

This article examines how geomagnetic activity influences 160-meter radio propagation. K9LA analyzes observations of enhanced signals preceding K-index increases. Modeling shows that as ionospheric electric fields rise from 0 to 75 mV/meter during early geomagnetic storms, they create an electron density valley above the E region, enabling signal "ducting" between the E and F regions. This effect vanishes at higher field strengths (100 mV/meter). The phenomenon may explain both exceptional 160m openings preceding 6m propagation and possibly Marconi's contested 1901 transatlantic reception, which occurred during a small geomagnetic disturbance.

Manually programming a Yaesu FTM-100 with hundreds of channels can be very fustrating. In this article the author highlights the difficulty of entering data with small buttons and the need to look up information for each channel. To avoid this tedious process author used RT Systems software as a solution. This program simplifies programming by allowing selection based on the radio model, download of frequencies from resources like RFinder, and quick loading onto the radio. While paid unlike the free CHIRP software used previously, the author emphasizes the time saved compared to manual entry, making the cost worthwhile.

The project details the construction of a small, portable **CW decoder** built around an Arduino Nano and an LM567 tone decoder circuit. It integrates an OLED display for output and is powered by a 1200 mAh Li-Po battery. The Arduino Nano is programmed with a modified version of the OST Morse Box firmware, originally based on Budd, WB7FHC's work, provided as a HEX file for flashing. The LM567 output connects to Arduino pin D2, while pins A6 and A7 are grounded due to the absence of potentiometers, simplifying the circuit. Standard I2C connections are used for the OLED: SDA to A4 and SCL to A5. The entire assembly, including the Arduino, OLED, and decoder circuit, is mounted on a perfboard to fit precisely within an old cassette tape box. This design emphasizes portability and compact form factor. Parameters for the decoder can be adjusted using a dedicated Windows Control program, offering flexibility in operation. The resource provides practical insights into adapting existing firmware for specific hardware constraints and achieving a self-contained, battery-powered **Morse code** decoding solution.

This page provides information on how amateur radio, or 'Ham' radio, is used by the yachting and small boat community for communication and weather information. It explains the global operation of amateur radio, regulations within the U.S., and the role of the American Radio Relay League (ARRL) in licensing and training. The page also highlights maritime 'nets' where Hams exchange weather reports, using voice and digital modes. It encourages establishing webpages for nets and mentions the MAROB and SKYWARN Programs for marine observation and severe weather reporting. The content is useful for hams interested in maritime communications and weather reporting.

The **CubeSat** standard, developed by California Polytechnic State University (Cal Poly) and Stanford University, facilitates frequent and affordable access to space for small satellites. This resource serves as a central hub for the CubeSat community, offering a comprehensive directory of active and past CubeSat projects, technical specifications, and educational materials. It details the standardized dimensions and mass constraints for these pico-satellites, which typically range from 1U (10x10x10 cm, 1.33 kg) to 12U configurations, enabling their deployment as secondary payloads on various launch vehicles. The site also provides insights into mission planning, component selection, and regulatory considerations for amateur radio satellite operations. Operators and developers can utilize the project directory to research existing CubeSat missions, understand their communication protocols, and identify potential collaboration opportunities. The platform's forum section allows for direct engagement with other enthusiasts and experts, fostering knowledge exchange on topics such as **AMSAT** frequency coordination, telemetry decoding, and ground station setup. This collaborative environment supports the development of new CubeSat projects, promoting innovation in amateur radio satellite communication and space exploration.