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HamCalc is a free collection of calculators for radio amateurs include Antenna ERP calculations, Attenuators, Audio Filter design, Coil Winding, Decibels, Great Circles map and calculator, HF Filters, HF Traps, Metric conversions OP Amps QRA Locator to Latitude/Longitude, Radio Horizon calculator, Resonance Satellite orbit calculator Timer calculations (555 timer)Zener Diode calculations Download zip By G4VWL

Contest Log Converter it's a Windows program that allow to convert data file between the most used Contest Log. The program allow you to convert 12 different type of contest, selected from the common contest managed from the Contest Log program. The follow program ,CT by K1EA, TR by N6TR and NA by K8CC are full supported with the conversion of the most famous world contests.

Also known as G5RV junior the half size G5RV feature reduced dimension and multiband coverage

Frequency Filer is database program designed for people who use a great many different radio frequencies. It is primarily intended for amateur radio operators, short-wave listening enthusiasts and scanner users. The program makes it easy to keep all of your important frequency information in one place, displayed in a logical format to facilitate easy retrieval. Frequency information can be displayed as a list and can be viewed on a world globe. Other features include easy data backup and custom field names. Included is database import utility that can be used as a general file conversion utility. The globe display can also be used as general geographic aid for countries, cities, states, rivers, and lakes. You may even find your home town. Windows Shareware

Demonstrates the construction of a **homebrew spectrum analyzer** designed by Wes Hayward, W7ZOI, and Terry White, K7TAU, enabling radio amateurs to build a capable test instrument without significant expense. The resource details a _double-conversion superheterodyne_ circuit, employing intermediate frequencies of 110 MHz and 10 MHz, and covers essential blocks such as the time base, logarithmic amplifier, resolution filters, and local oscillators. It highlights the use of hybrid and monolithic ICs, including mixers, amplifiers, and VCOs, to simplify construction while maintaining performance. The design supports useful measurements in the 50 kHz to 70 MHz range, with methods outlined for extending capabilities into VHF and UHF. The authors emphasize that this analyzer, while simple to build, is intended for serious measurements, requiring careful control of signal levels to avoid spurious responses. It uses an oscilloscope for display, with specific instructions for calibration and adjustment of various stages, including the log amplifier and IF gain. The guide provides detailed schematics and component lists for each section, such as the 110 MHz triple-tuned band-pass filter, which achieved **90 dB** image rejection, a significant improvement over double-tuned circuits. Practical advice on alignment and troubleshooting is included, drawing on the authors' extensive experience in RF circuit design.

RSCW demonstrates a Linux/Unix command-line utility engineered for **Morse code** decoding via a computer's sound card. It specifically targets the extraction of weak CW signals from noise, operating on 8-bit, 8000 samples/second audio input, typically from `/dev/dsp`. The program outputs decoded characters to `stdout`, supporting user-specified speeds in words per minute (WPM) and carrier frequencies. While effective for machine-sent signals, it exhibits a 2-second decoding lag and requires manual speed input, making it less suitable for general-purpose, real-time contest operation. The resource details the program's components, including `rscw` (the main decoder), `rscwx` (an X11 graphical auxiliary for spectrum and internal signal visualization), `rs12tlmdec` (a specialized decoder for RS-12 amateur radio satellite telemetry), and `noisycw` (a utility for generating noisy Morse signals for testing). Installation instructions involve downloading a `.tgz` file, compiling with `Make`, and requiring the FFTW library (and GTK 2.0 for `rscwx`). Performance is illustrated with a .wav file example of a 12 WPM, 800 Hz CW signal at 12 dB Eb/N0, showcasing RSCW's near-error-free decoding of a test message. The site provides command-line examples utilizing `sox` for audio conversion and `noisycw` for signal generation, inviting comparisons with other decoding software and human operators, particularly for weak signal conditions.

The RigPix database entry provides a comprehensive technical overview of the Icom IC-746 amateur HF/VHF transceiver, detailing its operational parameters and physical characteristics. It specifies the transmit frequency ranges across 10-160 meters plus WARC bands, 50-54 MHz, and 144-146/148 MHz, alongside receive coverage from 0.03-60 MHz and 108-174 MHz. The resource outlines supported modes including AM, FM, SSB, CW, and RTTY, noting a tuning step resolution down to 1 Hz and a frequency stability of ±5 ppm. Key electrical specifications are presented, such as a 13.8 VDC power supply requirement, current drain figures for RX (1.8-2 A) and TX (Max 20 A), and RF output power ranging from 5-40 W for AM and 5-100 W for FM, SSB (PEP), and CW. The entry details the triple conversion superheterodyne receiver system, listing IF frequencies at 69.01 MHz, 9.01 MHz, and 455 KHz, along with sensitivity ratings for various modes and bands. Transmitter section specifics include modulation systems and spurious emission levels. Additional features like a built-in auto ATU, electronic keyer, simple spectrum scope, DSP, and CI-V computer control are noted. The page also lists related documents, modifications, and an extensive array of optional accessories, including various filters, microphones, and external tuners, providing a complete profile of the IC-746.

Conversion of Zetagi HP201 SWR wattmeter for HF Amateur Bands by G8ODE

PA is a JAVA software package containing several programs, SW/VHF/UHF Logbook (imports format from RADIOMAN, VMT), Log conversion to HTML format, Import and export functions for RADIOMAN, CT RES files, BV QSL Labels, CSV etc. Internet DX-Cluster support, Keeps track of your worked Callsigns, Checks your worked Grid Squares per band, Databases for worked Grids and Callsigns Uses K1EA CQWW.CTY country file, Easy command line version for terminal operation Moontracking as clock, Pathloss calculation

A 500-watt mobile antenna project details the conversion of an old 10m hamstick into a highly efficient, multiband "bugstick" for HF operation. The core modification involves replacing the original coil with 25 turns of 6 turns-per-inch, 1.5-inch diameter coil stock, fabricated from #14 wire. This design, intended for a 3-magnet mount on a vehicle cab, achieves resonance on multiple bands by shorting out specific turns on the coil, similar to a **bugcatcher** antenna. Measurements taken with an MFJ-259 analyzer on a GMC pickup show 0 turns shorted for 20 meters (14.2 MHz), 10 turns for 17 meters, 16 turns for 15 meters, 19 turns for 12 meters, and 23 turns for 10 meters. The construction emphasizes using UV-resistant tie-wraps and #14 solid wire with crimp lugs for robust RF connections, bypassing the fiberglass rod for current flow. A bonus section details a 40-meter version, utilizing 48 turns of 8 TPI, 2-inch diameter coil stock.

Free Logbook conversion program that allows the conversion of some old DBF log files (DXLog, EasyLog, LogPlus, TopLog, TurboLog TotalHAM92) to the ADIF Format, 3.8Mb ZipFile

Freeware , 3.8 MB executable that allows the conversion of some old DBF log files (DXLog, EasyLog, LogPlus, TopLog, TurboLog TotalHAM92) to the ADIF Format by TRX-Manager authors

One hundred and fifty words per minute (WPM) is a configurable speed setting in this online Morse code translator, which facilitates bidirectional conversion between plain text and **Continuous Wave (CW)**. Users can input text to generate corresponding Morse code, or enter Morse code using dots and dashes to receive a text translation. The tool supports various alphabets, including Latin, Cyrillic, Ukrainian, Hebrew, and Arabic, broadening its utility for international communication. The platform offers multiple output methods for the generated Morse code, including audible playback, visual flashing, and device vibration. Advanced configuration options allow for precise control over the sound's pitch (frequency), volume, and overall speed, including a **Farnsworth speed** setting. This flexibility enables users to customize the learning or communication experience to their specific needs. Additional features include the ability to save the generated Morse code audio as a WAV file and to create shareable links for messages, which can be sent with or without the accompanying text. The interface is entirely web-based, built with HTML5 and JavaScript, ensuring broad compatibility across modern browsers.

The Hermes-Lite is a low-cost direct down/up conversion software defined amateur radio HF transceiver based on a broadband modem chip and the Hermes SDR project. It is entirely open source and open hardware, including the tools used for design and fabrication files. Over 300 Hermes-Lite 2.0 units have been successfully built.

This page details (in brief) the component changes to modify a Cybernet series 27MHz CB transceiver to 50MHz.

The Weather Fax plugin for OpenCPN allows you to directly open image files or decode audio faxes into images. With easy calibration, these images can be overlaid on charts. It supports image conversion in Mercator, polar, conic, and uniform coordinates and can transform any image into a raster chart. Additionally, it includes a built-in database for HF radio fax stations via SSB and another for retrieving data from meteorological websites.

This article explores the powerful features of AutoEZ as an Excel application working with EZNEC antenna modeling software. The article demonstrates how variables, equations, and formulas enable versatile antenna design and automatic optimization. Through practical examples including dipoles, inverted vees, delta loops, and monopoles, the author shows techniques for achieving resonance, implementing transmission line resonators for broadbanding, and optimizing antennas across frequency ranges. The step-by-step demonstrations cover unit conversion, coordinate calculations, segmentation considerations, and SWR optimization. This practical guide illustrates how AutoEZ extends EZNEC's capabilities, making complex antenna modeling more efficient and accessible.