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Just a simple signal generator based on ADF4351 module from fleebay allows you to generate one single frequency that can go up or down in 100Khz steps via two push buttons.

The program serves to assist in a ham-radio activities secretarial with his hobby , such as Printing QSL cards or print labels directly from the program , printing envelopes and mailing envelopes for the feedback you send direct QSL cards, download address for sending cards direct from QRZ.COM or for any station. Checking whether for the QSO and his country is present QSL bureau.

July 2017 DXpedition to Miquelon SSB, CW, RTTY - 80M - 10M

This stacking offers a well known simple phasing technique. All elements can be fed in parallel by open wires provided that they are fed in phase. This can be achieved by twisting the open wire phasing-lines at 180 degrees.

How to use AI (Artificial Intelligence) to identify Radio signals using a RTL SDR dongle and Linux (Ubuntu). This solution implement a framework using Keras and TensorFlow to learn and recognize the RF signals.

World Flora and Fauna in Latvia

A list of announced DX operations compiled by VA3RJ

Vertical Base Replacement Coil. Wolf River Coil build quality antenna coils that are easy to tune and easy to install.

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

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

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.

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

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

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

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

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

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.

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

This web page is part of a self-help program for licensed amateur radio operators and radio pirates.

The TARPN NinoTNC is a USB 1200/2400/4800/9600 baud KISS-TNC project

This is a simple 2.4 GHz SWR meter which is based around surplus microwave hardware which can be easily found. The main component is a MECA -20/-20 dB Directional Coupler which has a frequency range of approximately 700 MHz to 2.5 GHz.

A list of links on Crystal Radio projects and related reources

DXFile is a Windows shareware application designed for amateur radio operators, providing comprehensive log management capabilities. The software, developed in Pascal, facilitates real-time and deferred QSO entry, automatically populating fields like frequency, mode, and DXCC country based on user input and system time. It includes features for searching, modifying, and deleting QSO records, with options to sort logs by date, callsign, or entry order. The program offers various printing functions, including QSL card labels in multiple formats, and can generate standard logbook printouts. Beyond basic logging, DXFile integrates modules for tracking progress towards major operating awards such as DXCC, _IOTA_, WAZ, WAS, DDFM, and DIFM. It provides detailed summaries of contacts by band and mode, including graphical representations of HF traffic. A dedicated QSL Manager module assists in processing received QSLs, allowing users to mark confirmations and print multi-line QSL labels. The application also incorporates a DXCC list viewer, which can be updated to ensure accurate country and zone data for logging and award tracking. A distinctive feature is its HF propagation prediction module, which calculates optimal frequencies and signal levels for paths between **250 km** and **6000 km**, considering both E and F layer ionospheric conditions. This module helps operators determine the best times for long-distance contacts. Additionally, DXFile includes a _Web-Cluster_ interface, enabling connection to various DX cluster servers like DXLITE, DXSCAPE, and NC7J for real-time spot information.

The author has build the Hermes-Lite SDR v1 and v2 versions describing with a very accurated text and picture the process. Additionally has documented measurements for each component

Tips and tricks on programming the Yaesu FT-991A, from software installation and connecting to the PC via the USB Port, to properly programming memories.

Modification to an old cellular phone base station modules, with a fairly reduced output power (10 watts or so), the stock power amplifier modules will cover the 2.3 GHz and 2.4 GHz amateur radio bands.

This air-core solenoid style RF inductor calculator calculates the inductance, wire size, number of turns, and other parameters for an air-core solenoid inductor used in radio frequency (RF) circuits, based on user input of frequency, desired inductance value, and physical dimensions.

Creating a 2m Fm Repeater with a Raspberry Pi (B) and a RTL dongle.

Review of Yaesu VX-3R 2 m/70 cm FM transceiver. Receives 0.5-999Mhz AM/FMN/FMW, Transmits 144-148 and 430-450Mhz VHF/UHF FM.

Operating within the low-frequency spectrum, transformers serve critical roles in antenna systems, particularly for 160m applications. The resource details the construction and performance of 1:1 transformers built on BN-73-202 cores, emphasizing their use as hybrid combiners or phase inverters for RX antenna arrays. Measurements reveal that these transformers exhibit minimal losses, around 0.12 dB at 1.8 MHz, with variations based on wire type and number of turns. The analysis includes comparative data on transformer performance, highlighting the impact of different winding techniques on frequency response. Notably, the use of coaxial cable for winding improves bandwidth while maintaining low-frequency efficiency. The resource also discusses braid breaker transformers, which minimize inter-winding capacitance, achieving low losses around 0.21 dB at 1.8 MHz. These insights are crucial for optimizing low-band antenna systems, allowing operators to make informed decisions regarding transformer design and implementation.

Reflected power and VSWR Metering on Yaesu FT-817, and proper interpretation of real values. The power output meter it is a relative indicator of the antenna match that the radio is experiencing. Reference table and how correctly read the values of the Yaesu internal meter.

The Steampunk-styled air cannon sending tennis balls flying at 500 mph!

Common-mode chokes are useful solutions for RFI reduction. Winding a few turns of coaxial cable on the FT 240-31 toroid can reduced the noise below the received noise floor. In this article author measure different chokes

This project revisits a minimalist software-defined radio (SDR) receiver built using a Raspberry Pi Pico, now optimized for simplicity and affordability. Designed for breadboard assembly with through-hole components, the receiver covers 0–30MHz, supporting CW, SSB, AM, and FM modes with an OLED display and spectrum scope. Key improvements include enhanced frequency accuracy, reduced op-amp saturation, and lower-cost components. Powered by three AAA batteries, it delivers standalone operation for global signal reception. Ideal for hobbyists, the design fosters experimentation and is documented with firmware and schematics available online.

Signal to Noise Ratio, definition and application to Radio Communications. Signal to Noise Ratio (SNR) is a figure of merit that compares the level of a desired signal to the level of background noise.

This multiband transverter project features power output at 13,8V 50MHz 15W, 70MHz 10W, second harmonic < 65dBc. Single N connector of antenna, suitable for a dual band Yagi. Article include Block Diagram for Dual Transverter and low pass filters

Mad your own simple FS meter. It is the simplest thing to make and is good enough to see if the antenna under test is radiating more power than your old ground plane, old mobile vertical or just radiating at all in a particular direction or in all directions.

This project taps into the NMEA stream and provides both a visual display with an LCD and also LED indicators and a sounder. The LCD outputs include 3D Lock, 2D Lock and NO Lock while the UTC time is also displayed to screen.

Kantronics Pinouts with information on Icom, Kenwood Motorola, Yaesu and Vertex radio connections.

Home made 40 meter transceiver project. The receiver is a Progressive Receiver with a few modifications. The Transmitter is a modified MFJ Cub circuit. Includes schematic and circuit diagrams for Receive Input Filter, 3-Pole 500 Hz Cohn Filter and 7 MHz Double Tuned Bandpass Filter

Review of the excellent ICOM IC-R8600 Wide Band SDR communications receiver. Featuring Direct Sampling SDR below 30 MHz Hybrid Superhet / SDR above 30 MHz.

A simple superheterodyne receiver (3.5–30 MHz) for amateur radio achieves stable SSB-CW reception using modern BJTs, an AD831 mixer, a 6-pole quartz filter, and Seiler oscillators. Designed with high IF (4.5 MHz), compact AM-FM variable capacitors, and modular resonant circuits, it ensures selectivity, image rejection, and stable tuning. Built in a copper-lined wooden case, it features practical assembly techniques but lacks advanced features like AGC or S-meter. Effective on basic antennas, it achieves global reception.

A collection of ham radio clip art royalty free. Additional amateur radio clip art can be found changing the search terms.

A Different way to construct a tried and true antenna out of PVC, especially for the 10 meter and higher frequencies.

An technical page on coaxial cables that describes what coax cables are, how do coax cables works, what are RG cables and difference with several coax cable types, what they are used for, connector types and cable sizes