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A DIY cantenna can extend your WiFi range by building a 2.4 GHz high-gain antenna using accessible materials. The design, based on waveguide principles, uses a cylindrical tube to capture WiFi signals and can even connect to access points half a mile away in ideal conditions. While the ideal tube diameter was hard to find, a 4-inch aluminum dryer vent was chosen despite theoretical limitations. The cantenna offers a cost-effective, functional boost for your wireless network.

The earliest known historical record of the name Uzice is found in a document in the Ragusan archives, dated October 9th, 1329. In memory of this date, October 9th is now Uzice City Day. Earlier settlements in the vicinity date back to the Neolithic times. Throughout history, this area has been at a crossroads connecting economies and cultures North-South and East-West. To this day, Uzice is an important economic, industrial and cultural center. Award is active from October 1st to October 16th each year. To win you have to collect enough points making contacts (QSOs) with amateur radio stations which base locations are in the Uzice City Area.

This blog post by VE3VN discusses the design and performance of a 40-meter reversible Moxon antenna. The antenna provides coverage between southeast to west by default, with the ability to reverse for coverage from east to northwest. The post explains how the antenna performs well in various directions, focusing on the Caribbean, South/Central America, the US, and Europe. Detailed measurements and design considerations are shared, highlighting the accuracy of the model and the critical importance of coil inductance. The post also mentions the use of NEC5 for accurate modeling. Overall, this detailed discussion provides valuable insights for ham radio operators looking to optimize their antenna setup.

Installation of Female N-Type Connector on 1-5/8 RFS Cellflex Cable

SatNOGS DB is an effort to create an hollistic, unified, global database for all artificial objects in space (satellites and spacecrafts). You can view and export the data, contribute to it, or even connect your application using API.

The Dipole Bazooka Antenna for 40 meters is a popular choice among amateur radio operators. Its design allows for easy construction using materials like RG58 coaxial cable and PVC. Measurements are calculated using specific formulas; for instance, at a frequency of 7,100 MHz, the total length is approximately 19.74 meters. This antenna offers a performance range of 97% to 99%, with an impedance of 49 to 52 ohms. Additionally, it can handle up to 1 kW of power and requires no modifications for connection.

The most basic form of repeater receives communication on one frequency and re-transmits it on a different frequency, a process known as duplex communication. This capability significantly extends the range of handheld and mobile radios, as repeaters are typically situated at elevated locations with high-gain antennas and greater transmit power. Repeaters commonly operate with FM modulation on the VHF (30 MHz – 300 MHz) and UHF (300 MHz – 3 GHz) amateur bands, which are ideal for portable and mobile devices. Access to repeaters is often controlled by a CTCSS or PL tone, an inaudible signal that prevents the repeater from retransmitting background noise. This mechanism ensures efficient use of the frequency and prevents illegal continuous transmission. Canadian regulations, for instance, require an Advanced amateur radio license and an available frequency within the band to set up a repeater, each assigned a unique call sign and transmit frequency. Configuring a radio for repeater use involves knowing the repeater's transmit frequency, its receive frequency offset (e.g., -600 KHz for VHF or +5 MHz for UHF), and the necessary CTCSS tone. The article references resources like Repeater Book for locating repeaters and provides practical examples for initiating and concluding a basic repeater session, emphasizing clear identification and concise communication.

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.

Well, firstly the 12 Volt source will typically vary anywhere from 11 Volt to 15 Volt, and then a battery needs a controlled charge current and voltage, which cannot result from connecting it directly to a voltage source.

A C-Pole Antenna for QRPxpeditions describes a DIY C-Pole antenna designed for QRP (low-power) expeditions, inspired by KF2YN’s ground-independent vertical model. After adjustments, it achieved a 1:1 SWR at 14.060 MHz, rising to 2.5:1 at 14.35 MHz. A choke balun, comprising 15 turns of RG8X around a 4” can, was essential for optimal performance. Compact and self-supporting, the antenna enables reliable communication with minimal setup. Contacts included stations across the U.S., and even a 4,600-mile connection to Spain using only 5 watts.

This DIY Yagi costs less than 20 Dollars, and let you increase the performance of your connection. With this project you can build a better Yagi beam antenna resonant on 850MHz, a 8 element yagi directional antenna

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 HamAlert Cluster Client is a Windows program developed by OE3IDE to connect to the HamAlert system created by Manuel Kasper (HB9DQM). This system notifies users of new spots using various criteria through app notifications, SMS, Threema, and Telnet. The HamAlert Cluster Client enhances this functionality by providing taskbar notifications on Windows 10 and 11 PCs. The program is easy to use, requiring no installation—just download, unpack, and start. It includes features like a logfile for tracking activities.

The PicoFox is a versatile fox transmitter for 2-meter ham radio operators, built around the RP2040 microcontroller. With open-source hardware and software, it can be customized to suit your needs, from APRS to other digital modes. This fully assembled transmitter comes with a rechargeable battery and antenna, ready for use. The design allows for easy addition of features like sensors or interactivity. Modulation is handled in software for smooth FM output, with ample CPU, flash, and GPIO available. Configure your PicoFox by connecting it to a computer via USB and adjusting settings in a text file. Explore the possibilities of this innovative transmitter for your amateur radio projects.

Hamlog is online cloud platform for active amateur radio operators. It supports various on the air activities of various clubs, associations and national amateur radio organizations, allows them to create award programs and deliver awards to those who earned them. Hamlog also has a built-in real-time logger, which allows operators to enter QSO in the system as they make them. It supports multiple callsigns, multiple locations, multi-station activities, etc. Soon it will allow to connect transceivers and other ham radio devices right to the browser, allowing easy online logging virtually anywhere.

Home made freeware utility that allows to power on or shutdown the Yaesu FT rig. It has been tested on the FT-5000. It works also on FT 450 950 1200 2000 3000 5000 9000. It does NOT require any installation, just the exe files. Available in client server mode for remote connections

AutoEZ, Automated use of EZNEC, is an Excel workbook that works alongside EZNEC antenna modeling software version 5.0 or later. With AutoEZ, you can control different aspects of your model using variables and run multiple EZNEC test cases automatically. Formulas in Excel allow you to modify any part of the model. AutoEZ's interface resembles EZNEC's. Enabling macros in Excel might be necessary before using AutoEZ. The program opens various model file formats including EZNEC (.ez), NEC (.nec or .inp), AO and NEC/Wires (.ant), and MMANA-GAL (.maa). You can set the frequency and/or variable values for the test cases to be run through EZNEC. AutoEZ allows you to create animations showcasing how the pattern changes as the model configuration is modified. You can download a fully working, but limited demo copy from this site.

This document outlines the construction of a homebrew Buddipole antenna variant, designed for portable use and emergency services. The antenna utilizes telescoping whips and loading coils, enhancing its versatility across various HF bands. Key components include fiberglass rods, brass fittings, and Anderson Power Pole connectors, ensuring robust electrical connections. The design emphasizes non-inductive materials to minimize interference, while practical assembly techniques, such as epoxy and heat shrink tubing, are employed for durability. This variant aims to improve upon traditional Buddipole designs, offering greater strength and functionality.

Ferrite E-cores offer a practical solution for constructing baluns, especially when connectors are already mounted on cables. These cores, commonly used in mass-produced pulse transformers, allow for multiple turns without dismounting connectors, making them ideal for control and power supply cables. The material of E-cores is generally suitable for common mode baluns up to 15 MHz, providing a cost-effective option for amateur radio operators. E-cores can often be sourced from old switch-mode power supplies, adding to their appeal for those looking to utilize existing resources. A notable example involves a balun on a USB cable using a Ferroxcube E 32x16x9, 3F3 core with four turns, secured by three cable ties. This setup demonstrates the ease of construction and stability achievable with E-cores. Another example features a balun with eight turns of shielded cable with RCA connectors on the same core, achieving 140 uH inductance at low frequencies. The impedance plot for this configuration is measured between the shield ends, illustrating the effectiveness of E-cores in practical applications. The article includes detailed figures and descriptions, providing valuable insights into the construction and application of baluns using ferrite E-cores. These examples serve as a guide for amateur radio enthusiasts looking to enhance their setups with cost-effective and efficient solutions.

Learn how to construct a balanced Antenna Tuning Unit (ATU) for your ham radio equipment. Follow the instructions provided by Bengt, SM6APQ, to create a variable capacitor insulated from the ground for additional safety. Discover how to set up the ATU for the 20 to 10m band with proper spacing between coils. Use low power when adjusting the ATU for lowest SWR. Avoid using switches and opt for banana plugs for flexible connections. Visit the Creative Science Centre website for more information and resources on ATU construction.

This article provides an overview of setup Direwolf and QtTermTCP for HF packet radio operations. It covers important tasks such as setting up a Direwolf TNC, connecting with stations, and engaging in packet-based chat (K2K). It also looks at how to use nodes as relays and access basic BBS services. The paper also includes HF packet network etiquette recommendations and a description of how to handle common packet transmission issues, making it a useful resource for amateur radio enthusiasts.

This article published on QEX details measurements of tree conductivity and permittivity at HF frequencies, addressing a long-debated topic in amateur radio. N6LF conducted experimental impedance measurements on Douglas fir and maple trees using a vector network analyzer with rings of nails inserted into tree trunks. Results showed that tree conductivity increases with frequency while relative permittivity decreases, similar to soil characteristics. Measured conductivity ranged from 0.06 to 0.4 S/m at 10 MHz, aligning with values used in previous research. These findings validate that NEC modeling can reliably estimate trees' substantial impact on HF antenna performance.

Boondock Echo offers a revolutionary communication experience with an internet-backed recording and playback device for two-way radios. It ensures clear, reliable communication in remote or challenging conditions. Key features include real-time recording, internet connectivity, seamless integration, playback flexibility, rugged design, and a user-friendly interface. Services include product training, hardware maintenance and repair, customization, and regular firmware updates for optimal performance.

BktTimeSyncPhone synchronizes the PC time using the smartphone GPS connected via Bluetooth. Great for use with digital modes like FT8, JT65, JT9, JS8Call and others, especially when you do not have internet connections. To run this program, you need to install BktTimeSyncServer on your PC and the BktTimeSyncAndroid app on your smartphone. The program works with all versions of Windows 32 or 64 bit and requires Java version 8 or higher. The app requires an Android smartphone version 4.4 or higher.

Paul McMahon details the design and construction of a four-element Yagi antenna for the 50-52.5 MHz range, published in Amateur Radio Magazine (Dec 2011). The antenna, featuring a raised driven element and a capacitive/DC connection using copper strips, maintains consistent VSWR and performance despite two years of weather exposure. The design utilizes inexpensive plumbing conduit for the boom and provides detailed construction guidelines, parts lists, and performance analysis through 4NEC2 simulations.

The guide outlines necessary components, including a 2m FM analog radio, USB audio adapter, and Raspberry Pi. Building a cable to connect these elements is assumed, as is knowledge of Raspberry Pi OS installation.

The resource details the construction of a 433 MHz LoRa APRS iGate and a tracker, both built around _TTGO T-Beam v1.1_ microcontroller boards. Each board integrates an OLED screen, WiFi, GPS, and an SMA antenna connector, powered by an 18650 3.7 V lithium-ion battery or microUSB. The iGate operates on 433.775 MHz, with its status verifiable on aprs.fi, demonstrating practical implementation of LoRa-based APRS solutions. The methodology involves programming the modules using Visual Studio Code with the PlatformIO plugin. This process loads the necessary firmware and a JSON configuration file, which includes the operator's callsign and WiFi credentials for the iGate. The guide emphasizes the ease of programming and provides specific steps for configuration. Initial testing of the iGate and tracker, including smart beaconing configuration, is documented. The low power output of approximately 200 mW from the LoRa board's transmitter is noted, with suggestions for range extension through improved antennas or RF amplification. The author, N4MI, plans to deploy a higher-gain 70cm antenna for the iGate.

NetFinder is the ultimate directory for Ham Radio and SWL enthusiasts, designed to connect Amateur Radio operators through organized nets. Nets are scheduled gatherings on specific frequencies, ranging from formal emergency communication training to casual chats among Hams. Offering a platform for camaraderie and skill-building, NetFinder simplifies the process of discovering nets, fostering deeper engagement in the hobby. With a vision of cataloging every net worldwide, NetFinder aims to make these vital connections accessible to all operators, enriching the Amateur Radio community.

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.

**APRS TX I-Gate with APRX and the Universal Radio Controller** This project explores the creation of an APRS TX I-Gate to improve message delivery in amateur radio communications. Initial experiments involved configuring a picoAPRS v4 and later a G1LRO Universal Radio Controller (URC) with a Quansheng UV-K5 as digipeaters. While both setups successfully retransmitted signals, they failed to receive incoming APRS messages. To address this, a Raspberry Pi Zero running Debian and APRX-2.9 was repurposed to provide network connectivity, transforming the URC into an effective TX I-Gate for seamless APRS message handling.

This document provides comprehensive guidance on modeling and constructing multiband dipole antennas using traps. It addresses common segmentation issues in EZNEC modeling software, recommends optimal segment lengths for trap models, and compares trapped dipoles with paralleled multiband dipoles. While trap dipoles are significantly shorter, they exhibit lower gain and narrower bandwidth. Detailed instructions for building weatherproof coaxial traps include material lists, construction steps, and tuning methods. The guide notes that properly constructed coaxial traps introduce only minimal signal loss (0.6 dB) while offering practical multiband performance in a compact design.

Explore the process of creating a custom adapter for the Yaesu FT-8900 radio with a non-standard mic port. The article guides users through understanding the reversed pin-out of the RJ-12 connector on the 8900, providing a detailed circuit for adapting the voltage for electret-based mics. With a list of required parts and construction tips, this DIY project ensures seamless compatibility with standard electric headset mics.

A 13-foot total radiating element length is achieved by combining a Buddipole Long Telescopic Whip with 4 feet of modified tripod tubes, forming a low-profile, multiband antenna for **POTA** operations. The resource details the transformation of an Amazon Basics Aluminum Light Photography Tripod Stand, focusing on electrically isolating the top two radiating sections from the bottom support. John, VA3KOT, outlines component sourcing, including the 9-foot 4-inch fully extended whip, and emphasizes using adhesive copper tape for reliable electrical contact and conductive grease to prevent oxidation at tube connections. The construction process, while not requiring specialized tools, highlights careful assembly to ensure proper electrical conductivity and mechanical stability. The author's experience with this setup suggests its effectiveness for portable activations, offering a discreet profile compared to larger antenna systems. The design prioritizes ease of deployment and transport, making it a practical solution for operators seeking a compact yet versatile antenna for field use.

SvxLink is an advanced software suite for the ham radio community, initially launched in 2003 as an EchoLink application for Linux. Now a comprehensive voice services system, the SvxLink Server functions as an advanced repeater controller and can operate on simplex and duplex channels. It acts as an intermediary between transceiver hardware and applications, offering essential system services. The modular architecture of SvxLink supports customization, with modules in C++ or TCL. Key modules include a help system, parrot mode, EchoLink connectivity, DTMF repeater, voice mail, propagation warnings, and selective calling sequences. SvxLink's development and source code are available on GitHub, promoting open-source collaboration in the ham radio community.

Digital modes troubleshooting can be complex, even with devices like Digirig, which are designed for ease of use. This guide provides solutions for common setup issues in ham radio digital modes, applicable to Digirig and similar interfaces. Key troubleshooting tips include isolating problems, restoring previous configurations, ensuring correct USB and audio connections, and configuring software and hardware settings properly. Community forums offer additional support for specific issues.

An **Arduino LC Meter** provides an accessible solution for precisely measuring inductance and capacitance values, crucial for RF circuit design, filter tuning, and troubleshooting in amateur radio applications. This project details the construction of a low-cost, accurate instrument using readily available components, making it an attractive alternative to commercial units for hams and electronics enthusiasts. The build process involves assembling a resonant circuit, integrating an Arduino microcontroller for frequency measurement, and displaying results on an LCD. Key components include an Arduino Uno, a 16x2 LCD, a 74HC14 Schmitt trigger inverter, and a few passive components. The design leverages the Arduino's processing power to calculate L and C values from resonant frequency shifts. Calibration procedures are outlined to ensure measurement accuracy, which is vital for critical RF work. The project includes schematics, a parts list, and the necessary Arduino code, enabling hams to construct a functional LC meter for their workbench.

Demonstrates the construction of an **ATU-100 (N7DDC)** automatic antenna tuner, detailing the assembly process from component arrival to final enclosure. The resource covers winding the tandem match transformer, connecting the OLED display, and integrating optional control buttons. Specific attention is given to modifying the EEPROM settings for **QRP operation**, reducing the minimum tuning power to 1 Watt, and addressing potential RF interference with CPU by adding capacitors to button connections. The build log includes practical tips such as adapting RG58 coaxial cable strands for PCB mounting and utilizing a repurposed Macbook Pro cover for the custom enclosure. The author references external GitHub pages for comprehensive information, R0AEK's resources for additional details, and a video by MW0SAW for EEPROM configuration across different ATU-100 variants. Future plans involve field testing the completed tuner during SOTA or other portable activations.

The article explains how to adapt the YAESU FT817 transceiver so that it can be used to control Kuhne electronic transverters by transmitting at +12V via the coaxial wire. Different FT817 versions imply that some of the modification proposals that have been made so far don't apply to everyone. This tutorial provides a workaround that works with all FT817 models. It makes use of the external ACC socket, connecting an interior tiny circuit board to two thin wires. Follow ON7WP's instructions for using the rear antenna socket.

In his POTA activation, WK4DS experimented with radials for hamstick antennas. Despite sun and RF noise challenges, successful connections were made. Surprisingly, tuned radials proved unnecessary, simplifying setup. Hamsticks demonstrated versatility across frequencies. Increased power improved signal quality, sparking his curiosity for further exploration in radio technology.

This loop antenna is intended to be connected as an antenna for receivers that do not have a built-in antenna such as an HF set or an old tube radio. This square barrel is wound on a wooden frame. It consists of two windings that are galvanically isolated from each other, a main and a coupling winding. The diameter is about 40 cm.

This article presents a novel Top Loaded End-Fed Half-Wave (TLEFHW) antenna design for 20-meter ham radio operation. The antenna features a compact 14-foot vertical radiator with a capacitance hat configuration, eliminating the need for radials or ground systems. Using EZNEC modeling and field testing, the design achieves a 1.5:1 SWR across the 20m band with a 4.11 dBi gain. Key features include quick deployment, lightweight construction, and directional radiation pattern with 110-degree beamwidth. The design, while requiring a 45-foot footprint due to the top hat, offers an effective portable solution for amateur radio operators seeking a no-ground, no-tuner 20m antenna option.

The history of the radio is a fascinating one that changed how the world connected and communicated from distances both far and near. History of the Radio from Inception to Modern Day

open890 is a web-based UI for the Kenwood TS-890S amateur radio, and features good usability, clean design, and high-speed bandscope/audio scope displays, among other features not available either on the radio itself, or in the ARCP remote control software. It is currently only designed to interface with the TS-890 via a LAN (or wifi) connection, and not a USB/serial connection. It may work with the TS-990, as the command set is very similar, but is currently untested.

Antenna modeling is an essential technique for both amateur and professional engineers, enabling precise analysis of antenna performance. This guide, published on 4 different QST articles by L. B. Cebik, introduces NEC-2, a widely used public domain software for modeling antennas, focusing on its capabilities and practical applications. The series aims to demystify the modeling process, providing foundational knowledge and techniques for effective antenna design. Key concepts include understanding the method of moments and the importance of segmenting antenna elements. By mastering these principles, users can enhance their comprehension of antenna behavior and optimize their designs for improved performance.

Learn how LoRa mode can be used for APRS and connected mode packet radio, offering low power and long-range communication. Discover the growing popularity of LoRa-only APRS devices and the use of LoRa boards from manufacturers like Lilygo, Heltec, and RAK. Find out about firmware options like Ricardo Guzman's CA2RXU firmware, which incorporates previous work and offers KISS for external APRS clients. Explore LoRa APRS frequency and modulation settings in the UK, and consider adding CA2RXU firmware to lora-aprs.live for more radio-specific information. Dive into the world of LoRa technology for ham radio operators and experiment with different firmware options.

If you need a non-standard resistor value you could probably realize a close match using two resistor. If you use two resistor in series it is quite easy to figure out which values give the best match; on the other hand, using a parallel connection it is not so easy (at least for me) to find a good combination. This resistor calculation tool shows which combinations of two resistors (series or parallel) gives a match better than the closest standard value, for the E12 (10%), E24 (5%) and E96 (1%) series.

Compare the efficiency of two HF (or VHF) antennas by simultaneously transmitting FT8 on nearly the same frequency and analyzing PSKReporter SNR data. Determine the effectiveness of your new antenna compared to the old one in dB, to several decimal places. Run FT8 on two transmitters with different call signs and equal power, connected to each antenna. AntennaCompare analyzes global signal reports, isolating antenna performance.

Cloverleaf antenna is a circular polarized antenna which is way better than the cheap dipole antenna that comes with video transmitters and receivers. The Cloverleaf is a closed loop antenna which the signal and ground wires are connected. The cloverleaf antenna has 3 loops at 120 degree apart, and they are titled at 45 degree to horizontal plane.

Learn how to build a VHF 144MHz transverter connected to an LMR SDR radio using easily accessible components. The transverter works by mixing the 144Mhz input frequency with a 116 MHz local oscillator frequency. Explore the challenges of finding a 116 MHz crystal and the solution of using a programmable Si5351A oscillator. Follow the provided schematic for the RX and TX sections. The transverter design is still a work in progress, with ongoing trials to achieve optimal results.

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.