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A 40/80 inverted L antenna project by Myron WVØH

DX Propagation by DR2W! High resolution SNR maps in pseudo color. Propagation based on the actual sunspot number.

A loop antenna made with common RG-213 coax and rests on a cross made of 6 mm fibreglass rods anf a 6.5- 30MHz tune

A vertical antenna for 40 meters band by PA5MW

Homebrew a 2 meter square dipole antenna

Italian page about a home made a 1 to 40 balun with pictures and measurements on HF bands.

Demonstrates the construction of a 144 MHz turnstile antenna, detailing its design for omnidirectional, horizontally polarized VHF operation. The resource outlines the physical dimensions and materials required, including specific lengths for the radiating elements and the use of _RG-58_ coaxial cable for phasing. It covers the assembly process, emphasizing the critical spacing and connection points to achieve the desired radiation pattern and impedance matching for the _2-meter band_. The article presents measured _SWR_ performance across the 144-146 MHz segment, showing a low SWR of 1.2:1 at 144.5 MHz, which is suitable for general VHF use. It compares the turnstile's performance to a 9-element Yagi, noting the turnstile's advantage in providing consistent signal strength from all directions without requiring a rotator. Practical application for local FM simplex and repeater operations is implied, offering a simple yet effective antenna solution for fixed or portable stations.

DXPocketâ„¢ is a fast, stable, low-traffic, and easy-to-use DX Cluster program for Android-powered smartphones and devices. DXPocket monitors the DX Spots and Announcements available on the Internet at DX Summit web site and presents the information in a sortable grid format. With a few taps you can find a required station in the Cluster, obtain DXCC information of selected DX, send DX Spot or Announcement.

Cobalt Pet is a weblog focusing on shortwave radio. It features shortwave reception reports, product reviews, photos, listening tips, and links. International broadcasters and amateur / ham radio operators are monitored and discussed.

QRP and other projects from Honolulu, HI

Ham Radio Kits, including HF QRP SSB transceivers by EA3GCY

A homebrewed antenna for 2m handheld radios by TB1BIG

G0KYA Moxon antenna for 2 meters band

Amateur Radio operator interested in mobile & emergency operations, with some portable QRP operations.

KJ4WLH homemade dipole for 50 Mhz

EchoLink and IRLP Internet Radio Linking Project Node's, Hurricane Watch Audio Feed's and Info, Live Scanner/Other Feed's from the USA, Local Ham Frequencies, Online Receiver's, Shoutcast Live Audio Feed's from the USA, Southern California Frequencies and more

Live DX spots are presented through a _web cluster_ interface, utilizing both a world map and a Google Maps display for visualizing amateur radio propagation. The system provides real-time spotting data, enabling operators to track active stations globally. Users can observe current band conditions and station activity, which is crucial for optimizing contact strategies across various amateur bands. The platform's utility extends to contest operations and general DXing, offering a visual representation of where stations are being heard. While the primary function is DX spotting, the site also includes technical articles, such as instructions for interlocking two Flex Radios for single-transmitter compliance in contests, and a guide for constructing a simple **5KW** 1:1 balun for **160m/80m** dipoles using RG400 cable. This combination of live data and practical technical content supports both operational awareness and station improvement.

DX Spots web cluster interface with filtering features available to eham subscribers

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**.

G0KYA experience on hustler 5 BTV antenna

This modification will expand the tx frequency range of the Yaesu FT-991 from allowing just ham radio bands, to all bands 1.8 - 30MHz and 50-54 MHz.This information is solely for use by licensed members of MARS (Military Affiliate Radio System) or CAP (Civil Air Patrol)

Homemade hamstuf, mostly homebrew antennas in Dutch

Approximately 1,500 unique DX spots are typically visible on the _ODXC Web Monitor_ at any given time, providing real-time intelligence for amateur radio operators seeking DX contacts. This service aggregates spotting data from the _RW3XA-8 Obninsk DX Cluster_ node, presenting it through a straightforward web interface. Users can monitor current activity across various HF bands, identifying stations calling CQ DX or reporting rare entities. The platform supports both traditional telnet access for those using dedicated cluster clients and a Java-based web interface, catering to different operational preferences. It serves as a practical tool for contesters and DXers to track propagation, identify active stations, and plan their operating strategies. The cluster data includes callsigns, frequencies, modes, and spotter information, crucial for effective DX hunting. Integration with other spotting networks like _RBN_ and _PSK Reporter_ enhances its utility.

G0KYA review of the EH antenna for 20 meters band

Experiments with an 80 meter Inverted L Quarter wave antenna

As the sunspots return and DX propagation conditions to improve, the age old problem with QRM begins to show up on the amateur bands. Thif filter help you on improving reception

ARRL video review of the Yaesu FTDX-5000

An home made slim jim antenna for 2 meters band by VU2TQC

This tutorial provides step-by-step instructions for setting up the ICOM IC-7300 to work with WinLink and WinMor. The process begins with downloading the necessary USB driver from ICOM Japan, followed by configuring the radio settings through the menu. Key settings include selecting the correct output and data modes, as well as ensuring the USB serial function is properly set. Once the radio is connected to the PC via USB, the drivers will install automatically, allowing for seamless communication. After confirming the installation of the USB Audio CODEC and COM port, users are guided to download the RMS Client Software for WinLink. The tutorial emphasizes the importance of understanding the WinLink system and provides links to additional resources for setup. Finally, it details how to configure the WinMor modem settings, ensuring the ICOM IC-7300 is ready for effective digital communication. This guide is essential for operators looking to enhance their digital capabilities using the IC-7300.

This circuit stores a single morse code message as bits in an EPROM chip, the message is sent to a relay which can key a CW transmitter.

This is the schematic of asolid-state 7 MHz QRP CW transmitter by VU2NAN

Decoding NOAA APT weather satellite images is achieved with a homebrew receiver and a Turnstile Cross Dipole antenna, feeding data to a Pentium-3 500MHz PC running Windows XP and the WXTOIMG program. This setup, operated by VU2IIA in Mumbai, India, focuses on capturing and processing signals from NOAA satellites to generate visual weather data. The blog documents the technical aspects of constructing the receiving station, including antenna design and receiver integration. It provides insights into the practical challenges and successes of amateur satellite reception, specifically for Automatic Picture Transmission (APT) signals. Operational details cover the software configuration and image processing workflow necessary to transform raw satellite data into usable weather imagery. The content serves as a practical guide for radio amateurs interested in satellite meteorology.

An home made magnetic loop antenna project using a military surplus 150pf capacitor by KF5CZO

An efficient monoband end-fed half wave for 10m, 20m or any other HF band

An homebrew project for a 3 element coil-loaded Yagi beam antenna for 40 Meter band

Personal review of the Yaesu VX-6R handheld transceiver

Definition of smoothed sunspot number and R12 index

A very interesting blog article on a real world comparison on the popular multiband wire antenna, the G5RV, by Bob Raynor N4JTE

Demonstrates the _SQUIRL Field Day Logger_, a specialized software tool designed for efficient contact logging during the annual ARRL Field Day event. The resource details its core functionality, which includes real-time logging to easily readable text files, with filenames structured by callsign, band, and mode (e.g., K8DAA-20M-SSB.txt). It highlights features such as a real-time history grid of previous contacts, a dynamic USA and Canada map displaying contact locations, and a duplicate checker that provides audio notifications and pre-fills class/section data for previously worked stations. The software also includes an ADIF export function, enabling users to transfer logs to other general-purpose logging programs. The software's design emphasizes simplicity and ease of use, allowing for rapid on-the-spot training, as noted by users like W4CMB. It supports various operating systems, including Windows 98 through 8, and has been successfully run on Linux via _Wine_. Key usability enhancements include a "double-size" feature for improved readability and a "Space Mode" for quick field navigation. The version history indicates continuous development from 2001 to 2013, with significant additions like the real-time Field Day Map in 2003 and ADIF export in 2004, which allows for seamless integration with other logging platforms.

Building Eggbeater II Omni low Earth orbit satellite Antennas for 70cm by ZR6AIC

Ham radio blog dedicated to military radio equipment by EA3FOW

CommCat Mobile is a free integrated spot management, remote radio control, and logging app for the iPhone. CommCat is required for remote control.

A home made dipole antenna for 10m, 6m, 4m bands made with two sections of 450 and 300 Ohm ladder lines, cut to achieve acceptable SWRs on all bands

A 2 element Narrow Diamond Loop Array for 40 Meters by VE3VN

A mini balun 1:1 4:1 project by WV0H

Personal Blog devoted to ham radio topics,homebrew,antenna,satellite and other projects

Expeimenting with DSP digital signal processing on Arduino

An homebrew Lindenblad antenna designed specifically for LEOs reception.

Repairing and restoring a Yaesu FL-2100Z amplifier

Repairt a Heathkit SB-220 Linear Amplifier with a bad Plate Voltage meter