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The 144-430 portable j-pole antenna is designed for amateur radio operators seeking a lightweight and efficient solution for VHF and UHF communications. This antenna is particularly useful for portable operations, allowing hams to set up quickly in various locations while maintaining excellent performance. Constructed from readily available materials, it can be easily homebrewed, making it an ideal project for both beginners and experienced operators alike. The j-pole design offers a simple yet effective configuration that provides a good match across the 144 MHz and 430 MHz bands. Its vertical polarization and omnidirectional radiation pattern make it suitable for local communications and simplex operations. This antenna can be deployed in various environments, whether in the field or at home, and is well-suited for mobile applications. With proper construction techniques, operators can achieve optimal performance, enhancing their ability to make contacts during contests or casual QSOs.

Stuff for Homebrewer

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

Hear VLF audio from NASA online VLF radio receiver in Huntsville, Alabama.

The project details a DIY SWR/Wattmeter designed around an _Arduino Uno_ shield, providing capabilities to measure RF power from 2 to **200 watts** and Standing Wave Ratio (SWR) for HF amateur radio bands. This construction features a compact design, integrating the measurement circuitry directly onto a custom PCB that interfaces with the Arduino Uno microcontroller. Key components include a directional coupler for sensing forward and reflected power, precision rectifiers, and analog-to-digital conversion for processing RF signals. The Arduino firmware handles calibration, calculations, and displays the results on an integrated LCD, offering real-time feedback on antenna system performance. The design prioritizes simplicity for homebrewers. Performance specifications indicate accurate readings within the **2-200W** power range, suitable for typical QRP to medium-power HF operations. The project provides schematics and a basic overview of the software logic.

Graphic viewer for shortwave broadcasting and programming schedules. Supports viewing schedules in an expanding table and on a 24-hour Gantt chart using the local time and the UTC time display modes. Runs on multiple platforms.

The _59+ Log_ software, part of the 59+ collection, functions as a logging tool for Windows operating systems, specifically tested on Windows XP where its logbook feature operates smoothly. This collection also includes _59+ CW_, a module designed for Morse code operations, enabling keying of the COM port for transceiver control or simply listening to CW signals via the speaker. The software package, originally hosted on idealog.net, is now available for download as 59soft14.zip (3.4 MB) from IW5EDI's site. While the logbook application is functional, the _59+ CW_ application may encounter issues on newer Windows versions, as indicated by a failure to start on Windows XP during testing. The analyzer and convert modules within the 59+ suite require registration and do not operate in trial mode. Development and support for this software have been discontinued.

A 14 Mhz version of the vertical moxon antenna homebrewed.

Over 30 distinct shortwave (SW) receiver models are reviewed, offering insights into their performance, features, and user experiences. These evaluations, contributed by readers of the Usenet newsgroup **Rec.radio.shortwave**, cover a wide array of portable and tabletop radios, including popular units like the Grundig YB-400, Sony ICF-SW77, and various Realistic DX series models. Each review details aspects such as frequency range, tuning steps, SSB functionality, antenna performance, and construction quality, often comparing them to other receivers or ham transceivers like the Icom 725. For instance, the Grundig YB-400 review highlights its 144-30000 kHz AM/SSB coverage, direct keypad entry, and 40 station memories, noting its useful narrow bandwidth and tone switch for adjacent signal separation. It also discusses the **SSB mode** stability and the limitations of its 1 kHz frequency resolution for precise zero-beating. The review further details antenna performance, including the effectiveness of the built-in whip, the provided 7m reel antenna, and the potential for overload with larger outdoor antennas. Other reviews delve into specific issues, such as the Sony ICF-SW77's frequency display inaccuracies and timer malfunctions, or the Realistic DX-342's compact size and surprisingly good MW DXing capabilities despite its analog tuning. The collection provides practical, user-generated feedback on sensitivity, selectivity, audio quality, and ergonomic features, helping shortwave listeners understand the real-world performance and quirks of these receivers.

Two types of home-brewed 12/20 Ampere 13,8volt power supplies, including detailed part lists by ON6MU

A home brewed rotary dipole antenna for 12 and 17 meters band with pictures and construction details

This homebrewed antenna tuning unit also incorporates a 50-ohm QRP dummy load, power meter (1 or 10 Watts full scale), and SWR meter

This project started as a result of renewed interest in 40 meters coupled with the desire for an antenna system that would be more effective than the simple dipole.

Facilitates efficient logging of amateur radio contacts, offering a robust solution for hams managing their station activities. The software integrates _CAT control_ capabilities, allowing direct interfacing with popular transceivers from manufacturers like Yaesu, Icom, and Kenwood. This feature streamlines the logging process by automatically capturing frequency, mode, and other QSO details directly from the radio, reducing manual entry errors and improving operational efficiency during contests or DXing. _HAM-LCT_ includes a comprehensive database, enabling users to store and retrieve contact information, QSL data, and other relevant details for each QSO. The program supports various operating modes and provides tools for searching and filtering log entries, which is beneficial for award tracking and station analysis. Its design focuses on providing a user-friendly interface for everyday logging tasks. While the original author, _HB9CQV_, has discontinued development of HAM-LCT in favor of a newer logging application, this version remains available as a functional freeware option for Windows users seeking a dedicated logbook with integrated rig control.

Argo, developed by I2PHD and IK2CZL, functions as a specialized freeware viewer for various weak signal modes, specifically MTHELL, Slow CW, QRSS, and DFCW. It processes audio input to visualize and decode these extremely low-speed transmissions, which are often imperceptible to the human ear. The software's capabilities extend to EME (Earth-Moon-Earth) operations, where its sensitivity to weak signals is particularly advantageous for detecting faint lunar reflections. The application provides a visual representation of the received signals, allowing operators to discern patterns and decode information from signals buried deep within the noise floor. Its design focuses on extracting data from signals with very narrow bandwidths and long integration times, characteristic of QRSS and similar modes. This tool is distinctively useful for experimenters and DXers engaged in challenging weak signal communication, offering a dedicated platform for modes not typically supported by general-purpose digital mode software. Its specialized focus on _Slow CW_ and _MTHELL_ makes it a niche but effective utility for specific operating scenarios.

Over 45 years of amateur radio experience inform the homebrew projects detailed on this personal website, with a particular focus on microwave frequencies. The site showcases a 24 GHz transverter and a more recent 47 GHz transverter, demonstrating practical construction techniques for extreme high-frequency operation. These projects often involve custom circuit design and careful component selection to achieve stable performance at millimeter-wave bands. Key projects include a _harmonic converter_ for frequency measurement and a tracking spectrum analyzer, essential tools for microwave experimenters. The site also documents a CW sidetone generator and a TX/RX sequencer, illustrating fundamental building blocks for radio equipment. Details on a digital frequency meter and an S-meter/dBm meter provide insights into test equipment construction. Specific achievements, such as a **24 GHz** tropo QSO with DK3SE in 2021, highlight the operational success of these homebrewed systems. The content reflects a long-standing dedication to self-sufficiency in amateur radio, providing practical examples for those interested in building their own gear.

adsbScope is a freeware Windows application designed for processing _ADS-B_ (Automatic Dependent Surveillance-Broadcast) frames received from a compatible decoder. It identifies aircraft, calculates their real-time positions, and presents flight parameters in both alphanumeric tables and a graphical display. The software interfaces via a virtual COM port, receiving raw frames to provide detailed situational awareness, including a global coordinate grid, continental coastlines, over 4,000 **airport** locations, and major cities. Users can overlay OpenStreetMap tiles and view world state boundaries, with each tracked aircraft rendered with labels showing altitude, speed, heading, squawk code, and flight identifiers. When paired with the adsbPIC-decoder, adsbScope enables advanced hardware control, allowing users to toggle data filters for specific frames like DF17/18/19, adjust analog signal thresholds for reception fine-tuning, and manage system resets or bootloader activation directly from the PC. This functionality provides a customizable toolkit for hobbyist radar listeners, offering a robust alternative to commercial tools for processing aircraft data. The software displays up to **1090 MHz** transponder data and can track aircraft up to 250 nautical miles.

Icom PCR 1000 at NASA Marshall Space Flight Center monitoring meteor signals on 67.3 mhz.live.

The Elecraft K3, a popular HF transceiver, is often benchmarked against new market entrants. This article critically compares the Kenwood TS-590S to the K3, focusing on key technical specifications and operational aspects relevant to serious amateur radio operators. The author proposes three distinct evaluation methods: a circuit diagram comparison, an independent review analysis (referencing Peter Hart, G3SJX, in RadCom), and a real-world "ear test" by experienced contest operators on 40 and 80 meters. The analysis delves into specific receiver components, including the first mixer design, RF and IF amplifier performance, and the presence of an image noise filter. It highlights the K3's switched mixer and the potential for the TS-590S to utilize similar or improved designs, such as a classic filter with enhanced selectivity. The article also scrutinizes the second mixer stage, noting the K3's SA612 chip and its associated IP3 limitations, suggesting Kenwood might achieve benefits with a different mixer architecture. Further points of comparison include DSP capabilities, where the K3's high-performing DSP with KK7P's involvement is noted against the TS-590S's potential reliance on newer IC technology but possibly less refined software. The discussion extends to DDS and PLL implementations for phase noise and spurious emissions, and the utility of a second receiver for DX chasing and contesting, acknowledging its importance for some operators while being less critical for others. The article concludes by emphasizing personal preference in equipment selection.

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

Mirko Pelcl's extensive radio collection features numerous historical transceivers and receivers, with a significant focus on military communications gear. The collection includes notable examples such as the Wireless Set No. 19, various Cold War-era military radios, and even a rare WWII spy radio utilizing a Loewe 3NF tube. Visitors can explore detailed sections dedicated to sets manufactured before 1945, including those used for military exchange, and a separate category for post-1945 radios, particularly those from the former Yugoslavia. The site also delves into specific modifications, like a digital head conversion for the RU-20, and showcases a frequency counter built with a microcontroller. This personal archive provides a unique glimpse into the evolution of radio technology, from early vacuum tube designs to more modern solid-state military transceivers like the PRC-515. The content reflects Mirko's dedication to preserving and documenting these pieces of radio history.

The total length of the inverted L is 240 feet, which is 7/16th of a wave length long. It has a 92 foot horizontal linear load section 1 foot above ground that terminates into a home-brewed parallel network tuner by KN4LF

A really simple receiving antenna for 80 and 160 meter dxing by WA2WVL

Build a Low Power 4:1 Balun , by Charles Greene, W1CG with full-color, full-resolution graphics from the pages of QRP Homebrewer

The EF0604S is a compact 4 elements yagi antenna plan for six meters band featuring 8.77 dBi gain and a front back gain of 17.89 dB. Article includes elements dimensions and spacing, along to pictures of some homebrewed examples.

CallBook is an Amateur Radio application that allows you to look up call signs via the free WM7D server, the QRZ Online subscription service or the HamCall subscription server and track active APRS stations on www.aprs.fi. Lookup results can be emailed and the QTH can be instantly viewed in the Maps application

The **Black Cat CW Keyer** is a macOS application designed for amateur radio operators to transmit Morse code directly from their computer. It provides functionality for typing text to be sent, either immediately or buffered, and allows for the creation and transmission of pre-defined messages via single-key shortcuts. This software addresses the need for a flexible and accessible CW keying solution, particularly for Mac users who might find fewer dedicated ham radio applications compared to other operating systems. It integrates basic text-to-CW conversion, offering a straightforward interface for generating Morse code signals. Operators can utilize the Black Cat CW Keyer for various CW activities, including casual QSOs, contesting, or beacon operation. Its ability to buffer text allows for smoother transmission, while the single-key macro feature streamlines repetitive message sending, such as CQ calls or contest exchanges. While specific comparisons to other CW keying software are not detailed, its macOS focus provides a niche solution for Apple users. The program's utility lies in its direct approach to computer-based CW transmission, making it a practical tool for those seeking a dedicated **CW keyer** on the Macintosh platform.

ON6MU optimized 6/9 element vhf yagui antenna with antenna schematic plan and pictures of homebrewed samples.

Homebrewed jpole antenna for 50 mhz by IW0BZD, include pictures and schematics, in italian.

An homebrewed dipole antenna for 14MHz

Flexnet and AGW packet engine tested and reviewed by IZ7ATH

Report of solar & geophysical activity

Website for all Chesterfield Gateways on 446, using eQso.

Portable magnetic loop antennas - G4TPH Mag-loop antennas Reviewed in PW and RadCOM, Both QRP and QRO, Portable. The only Magloop on the market that is fully portable

Homebrewed SWR meters projects by G3TXQ

HF and VHF amplifiers homebrewed by GM3WOJ

QRPPAL, developed by WB2QAP, functions as a freeware QRP logging application for Windows 3.1 and Windows 95, initially introduced at the 1996 Dayton Hamvention FDIM QRP symposium. The software integrates the original "Logger" program, which was specifically designed for ARCI contest dupe checking and logging, alongside versions tailored for NW-QRP, MI-QRP Club, and Colorado QRP Club contests. It is distributed as a self-extracting archive, _qrppal!.exe_, approximately 1.2 MB in size, which unpacks _qrppal.exe_ and _setup.exe_ for installation. The program's modular design incorporates extensive QRP-centric databases, covering ARCI awards, QRP club listings, QRP periodicals, kit/vendor directories, and detailed rig reviews, often with photos. Noted reviewer Bob Gobrick, _VO1DRB_, described it as a "QRP Internet Web Site in a box" due to its comprehensive data modules, which are also user-modifiable. Installation involves running _setup.exe_ to create batch files like _setup95.bat_, which then establish a c:\qrppal directory and deploy the program files. Users initiate the application by typing "qrp pal.tkn" after setup. The Colorado QRP Club contest version should be avoided due to specific first name exchange requirements not supported by that module.

VHF UHF Amateur radio antenna and antenna parts, accessories for homebrewers, antenna kits, tubes, antenna masts, antenna tripores, insulators, power amplifier mosfet, power splitters by I0JXX

An home-brewed morse code CW filter with a central frequency of 800hz and a variable bandwidth from 230hz to 26hz by F5RDH in french.

An interesting homebrewed gamma match feed for a Halo Antenna

Small and inexpensive homebrew HF radio 5W Output, CW SSB AM FM, DSP, Speech Processor, Sprectrum Scope, Watefall Display. mcHF is a small, home-brewed amateur radio project. Firmware is released as open source.

EWE Antenna plan with a 9:1 balun

There is not a personal design on this page, just I've transfered useful notes from PHILIPS RF Bipolar Transistors - Data HandBook about BLY89C VHF Power transistor, which is very popular among Amateur Radio homebrewers

Amateur Radio Projects & Kits for homebrewers, includes DDS,sound card interface,programmers, hamcom, frequency counter, RF Power Meter, modems and more.

Homebrewed handheld RF powermeters for various sensors by DL5NEG

Elongated Terminated Loops, usage and details by K9AY Lewallen

A homebrewed antenna for 2m handheld radios by TB1BIG

Home brewed spider beam by VA7ST

Pirate radio recordings, addresses, links and QSLs

Operating on the 2200m band (135.7-137.8 kHz) often presents challenges for amateur radio transceivers, which typically exhibit poor receiver performance at these very low frequencies. This project addresses the issue by providing a design for a dedicated 137 kHz antenna preamplifier, specifically tailored to improve signal reception for radios such as the _Yaesu FT-817_. The preamplifier circuit utilizes a low-noise FET input stage, crucial for minimizing self-generated noise and maximizing the signal-to-noise ratio from weak LF signals. The design includes a detailed schematic, component values, and construction notes, enabling homebrewers to build a functional unit. The goal is to achieve significant gain, making the faint signals on 2200m more discernible and improving overall band usability. Key design considerations include impedance matching to typical antenna systems and ensuring stable operation across the narrow LF segment. The circuit aims for a **low noise figure** and sufficient amplification to overcome the inherent limitations of general-purpose HF transceivers when operating below **200 kHz**.