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DX Engineering is a source for antennas and antenna parts for radio amateurs and professionals. The website offers a wide range of products and resources for antenna projects and radio operation.

Download this color US ham radio band-plan in PDF format edited by ARRL

A program to design and print QSL cards on your computer, as well as design QSL cards for printing by commercial printers. This program overcomes many of the limitations that are present in other QSL design and print programs and methods. Works on Windows 7 to 10.

The _Astron RS35m Power Supply Schematic_ provides a detailed circuit diagram for this popular linear power supply, focusing on the rectifier and pass transistor stages. It presents the AC input and DC output sections, illustrating the component layout and interconnections critical for understanding its operation. The schematic is enhanced with specific annotations derived from the December 2005 QST "Hands-On Radio, Experiment #35 Power Supply Analysis." These notes offer insights into the circuit's functionality and potential analysis points, making the diagram more instructive than a bare schematic. The resource serves as a practical reference for hams interested in the internal workings or maintenance of the _Astron RS35m_ unit. This document specifically highlights the key components responsible for voltage regulation and current delivery.

Concentric Open Loop Antenna Fed Off-Centre similar to the cobwebb antenna but resonating on 20-17-15-10 meters band

Moxon antenna for 50 MHz, The Moxon rectangle is a quite broad-band antenna, but it is not quite broad enough to cover the entire band.

EasyPal is a sophisticated digital Slow-Scan Television (SSTV) application that utilizes soundcard technology to encode and decode SSTV signals. Developed by the late Erik Sundstrup (VK4AES SK), this software has evolved into a versatile communication tool for amateur radio operators, extending beyond basic image transmission capabilities. EasyPal implements Digital Radio Mondiale (DRM) encoding technology, enabling efficient data transmission over narrow 2.5 KHz channels on both HF and VHF frequencies with remarkable speed. The application supports multiple file formats, including jpg, pdf, txt, doc, and xls, as well as specialized forms such as ICS-213 and ICS-213 (ARES). Additionally, EasyPal offers email functionality through designated repeater stations with internet access. Its responsive development history and robust feature set have established it as a premier digital SSTV solution in the amateur radio community, though users of Windows 11 should note specific configuration requirements to ensure optimal performance.

The PringlesCantenna is an ultracheap Yagi-type directional antenna that can be built for under $10. The original Pringles Yagi was designed by Andrew Clap.

Measuring SWR and things every CB'er should know

The Bruce array is a simple, often-forgotten wire antenna array that is advantageous for 80 and 160 meters, where typical gain antennas are very large. This bi-directional broadside vertical array is only 1\4 lambda high and does not require a ground system. It offers substantially greater SWR bandwidth than the half-square or bobtail curtain. A 4-element Bruce array used by N6LF showed a gain of about 4.6 dB compared to a 1\4 lambda vertical with 8 elevated radials, with a 2:1 SWR bandwidth greater than 400 kHz. The antenna is simple and its dimensions are flexible.

The NCDXF/IARU International Beacon Project schedule provides precise transmission start times for 18 beacons operating on 14.100 MHz, 18.110 MHz, 21.150 MHz, 24.930 MHz, and 28.200 MHz. Each beacon transmits every three minutes, cycling through its callsign at 22 WPM followed by four one-second dashes. The initial callsign and first dash are sent at 100 watts, with subsequent dashes at 10 watts, 1 watt, and 100 milliwatts, enabling **propagation analysis** across varying signal strengths. The schedule lists the minute and second within each hour for the first transmission of each beacon on its respective frequencies. This resource allows **DXers** and **contesters** to accurately predict beacon transmissions for real-time propagation assessment. For example, 4U1UN transmits first at 00:00 on 14.100 MHz, followed by VE8AT at 00:10, and W6WX at 00:20, continuing the sequence. The page also notes recent hardware upgrades, such as the installation of IBP 2.0 controllers with Icom 7200 radios at some sites, and provides status updates for beacons experiencing hardware failures or those not recently heard, aiding in troubleshooting and managing expectations for monitoring.

This project details three variants of a vertical half-wave antenna design for the 4-meter (70MHz) amateur radio band. The antennas use end-feeding with a parallel-tuned circuit for impedance matching to 50-ohm coaxial cable. The first variant uses suspended flexible wire for portable use, the second employs a fiberglass rod with internal wire for permanent outdoor installation, and the third utilizes aluminum tent poles for quick mobile deployment. Despite the narrow bandwidth of the matching circuit, this suits the narrow 4m FM allocation well. The design offers an effective omnidirectional radiation pattern and can be constructed with readily available materials.

10 meters band aluminum 2-Element Moxon rectangle

Helix antenna calculator, to design and make helix antenna plans

A 6 m 50MHz J-Pole antenna by VKADC

Making your own 2 metre (146 MHz) 5/8th wave whip antenna

This article describes the construction of a Moxon rectangle antenna for the 70MHz (4-meter) amateur radio band. This compact two-element beam design features folded element ends, reducing its width to approximately 75% of a half-wavelength. The antenna was built using enamelled copper wire stretched over a lightweight fiberglass kite spar frame, with a direct coaxial cable feed connection. Initial testing showed a VSWR of around 1.3 with distinct nulls at 90 degrees when horizontally mounted. The author later tested vertical polarization and suggested that the antenna's compact size might allow for indoor loft installation.

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.

Easy to setup dipole antenna for 4 meters band by Tony Hawker G4CJZ

Interesting article on mobile antennas by Cebik. . The article offers advice for setting up and operating mobile antennas for ham radio use. It emphasizes the lossy nature of mobile-in-motion antennas but encourages users to rise to the challenge. Steps include safeguarding car electronics, choosing proper cabling, and carefully selecting and mounting antennas. It highlights potential issues like roof mounting, trunk lip grounding, and side-mounting for trucks. For stationary operation, options like dipoles or beams are explored, with safety tips for masts and guying systems. Lastly, it stresses safety, suggesting stopping the vehicle to operate whenever possible

This project shows how to build a 50-ohm dummy load using non-inductive resistors, oil for heat dissipation, and a simple assembly process. It enables accurate transmitter tuning, testing, and power measurement across LF to UHF bands. The setup allows meter calibration by measuring peak voltage, applying diode drop correction, and calculating RMS voltage and power precisely. Parts are inexpensive and widely available. With proper assembly, this dummy load offers extended service life, accurate readings within 2%, and a reliable alternative to costly commercial wattmeters for amateur radio applications.

Comprehensive list of beacons in the 50MHz band maintained since 2013 by G3USF.

Notes on building a basic wire vertical or horizontal antenna for 160 meters band by L. B. Cebik, W4RNL

This is a picture of a schematic diagram of a multifunctional interface for Yaesu FT-8x7 Series Transceivers. It will work for Yaesu radios like FT-897 FT-857 FT-817

A **90-foot tall** top-loaded vertical antenna for the 160-meter band is detailed, constructed from aluminum irrigation tubing. The design incorporates four sets of four guy wires for structural stability, essential for an antenna of this physical size. This _monoband_ vertical is optimized for low-band operation, providing a robust solution for DXing and contesting on 1.8 MHz. The document includes specific construction methods for assembling the aluminum irrigation tubing sections and securing the guy wires. While a full NEC model is not explicitly provided, the physical dimensions and construction materials are sufficient for replication by experienced builders. The antenna's height and top-loading configuration are critical for achieving efficient radiation on 160 meters, particularly in minimizing ground losses.

A free to download and print, amateur radio station log sheet in a paper US letter format

Download the PDF with USA Amateur radio HF band plan and common country prefixes updated in 2008 by Icom

KaWin is a Windows software that supports multiple Kantronics TNCs and multiple radio transceivers with an intuitive, graphical interface, setting a new standard of performance for digital radio communications. Software is not supported anymore.

A project by DL5DBM for a VHF UHF antenna suitable for handheld transceivers

WinTone v2.02 is a windows DTMF Decoder, run on old windows versions only.

The W8JK is a famous and effective DX antenna, first built by John Kraus, W8JK, in 1937. A Beam antenna with two parallel dipoles driven with opposite phase, with a close spacing of an eighth of a wavelength.

This program descrambles band inverted encrypted transmissions, usually found on VHF/UHF. It uses a NCO (numerical controlled oscillator) to re-produce the originally inverted audio band.

Microphone wiring for HTX-100

Ham Radio applications with the Arduino micro-controller presentation

The ITU and CQ Zones Map is a printable two-page PDF provided by Icom, displaying the world divided into ITU and CQ Zones. The purpose is to assist radio amateurs in identifying and understanding these zones for communication purposes.

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.

Monitoring Times, SWL, BCL, montly reports, Broadcast band, satellite television, long-wave coverage, Reviews of new products and radio-related software.

An illustrated and complete guide to soldering PL-256 coax plugs

NuMorse 2.20.0.0 for Win 7/Win 8/XP/Vista/Win 10 A complete rewrite of the original NuMorse used by thousands of radio amateurs to gain and upgrade their licenses. NuMorse offers an intermediate feature set that is somewhere between the lean and mean NuCode program and the vast array of features supported by NuMorse Professional. But NuMorse is no cut-down program. It has several unique features not found in other Nu-Ware products as well as a compact and intuitive set of controls that you will be able to learn quickly.Product is no more developed and out of support.

Freeware Hellschreiber decoding program for windows by Nino Porcino

Download ex1726 a 32-bit DOS radio control program for the ICOM M700PRO, M710 and M710-R NMEA computer interface.

Radio Incident Command Kit project is described in this article loaded with many pictures and go-kit composition.

A free to download and print, log sheet in A4 paper format for amateur radio stations

CWCom is a free morse code chat progam for Windows operating systems you can download free. Has been tested with windows 10. You can use CWCom to transmit and receive morse code and text messages over a LAN or even across the internet. CWCom can translate and decode morse code to text and encode text into morse code or flashing light, so you don't have to know morse code to use it.

The varieties of twinlead J-Poles and some performance standards, L. B. Cebik, W4RNL

46ft multi-band antenna for small gardens. Works well on 80m. An excellent DX performer and is an ideal replacement for your half size G5RV

Designing quagi and yagi antennas on 2 Meters, some preliminary notes by Cebik, W4RNL

A Primer for the new Packet Radio operator

Equipment and procedures to monitor ACARS

Great first time J-pole project. Covers most of the basics. This small and thin design also makes it good for several stealth applications.