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Modify an Analogue Sky TV Offset Fed Dish for AO-40 S-Band

This article presents a technical investigation into spurious emissions from the Yaesu FT-847 transceiver when operating on the 70MHz (4-meter) band. The author discovered significant problems with both factory "UK spec" and modified units. Spectrum analysis revealed that when transmitting at 70.2MHz, the radio produces numerous spurious signals, with the most prominent emission at 45.6MHz measuring only 3dB below the fundamental frequency. The study also documents poor power efficiency on 4m (10.3% at 30W output) compared to 6m operation (23.5% at 30W). Tests verified that jumper configurations had no effect on filter selection. The author warns that using these radios on 4m may violate license conditions due to excessive spurious emissions.

Thierry LOMBRY, ON4SKY, develops in several technical articles the way to select a transceiver. His website includes also some in-depth reviews

Official, and updated CQ Magazine Countries and Zone List available in various formats, text, word and excel formats.

Halo antenna plan for the six meters band

A 3 element yagi antenna project for the 144 MHz band by PY5ALZ in portuguese

On this page is the design for Dual Band 2M / 70cm antenna with 3.2mm elements. The antenna has a 50 ohm designed driver. This Yagi has a unique element called a Open Sleeve

VFO Stabilizer for Kenwood 120, 520, 820, 530, 830 Yaesu FT-101, 901,2 TenTec 580, 540, Triton, Corsair, Omni series, Swan 350, 500cx, Collins KWM 2 and 2A, Drake TR4, T4, R4, Heathkit HW101, SB 104a....and many others

Step by step instructions for setting up N1MM Logger to communicate with the TS-590S using the USB connection

HAMIC, is a program designed to simplify a number of calculations commonly used by HAMs. It is designed for the HAM radio hobbyist, but may be useful to others as well. HAMIC has a simple to use, but powerful graphical interface that allows solving simple circuits such as resistors in series or parallel, or more complex circuits such as L networks or T networks. As well, other calculations such as SWR and reactance conversions are supported. Windows shareware.

Converting A PC Power supply for Amateur Equipment

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.

United States and Canadian call sign/scanner frequency databases, Worldwide airport frequencies, FIPS codes, Mass Media searches for DXing and more!

To save a little time from calculating and experime nting when winding toroid cores here a chart of the most commonly used cores

A simple antenna tuner for 4m by Tony Hawker G4CJZ

How to Operate Ham Radio on a Linux Workstation

Comparing the TH-F7E with the Icom IC-E90

Amateur Radio Station owned by Matt Strelow. The station is designed for competition in the multi-operator multi-transmitter category of high-frequency DX contests. Running with 7 towers 6 rotators, 8 beverage listening antennas, and 4 spotting verticals

Sporadic-E clouds location and estimated MUF real time map by DXMAPS

A small antenna for limited space / lanai use.

Official website of the ICF group

The Old Tube Radio Network is dedicated to those real, American-Made, Old Tube CB Radios

Palm interface for the FT100D by Andre, HB9FBD

Premium quality, full color, custom QSL cards produced in America's Heartland, competetive rates. Produced by Hams for Hams!

One of the most useful antennas in the repertoire is the Marconi or quarter wave grounded vertical antenna. Its invention made it possible to halve the length of antennas, simplifying communications, especially at HF and below.

A dipole for 2m, 4m, 6m band an hamdwritten note for a homemade vhf antenna that can be tuned across the VHF band

Solutions to attach antennas to TH-D7 radio using a SMA to BNC adapter that can be used with any Kenwood hand-held radio shipped with SMA connectors.

This article documents the modification of 2 types of Hewlett Packard switching power supplies to enable their use as power sources for ham radio equipment

List of north america beacons transmitting on vhf and uhf bands compiled by WZ1V

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

German antenna manufacturer for VHF UHF antennas, Quad-antennas, yagi-Antenna, LPDA-Antenna, W-Lan Antennas.

Presents a dynamic, searchable database of shortwave broadcast schedules from around the world, enabling users to locate active stations or plan listening sessions based on scheduled transmission periods and frequencies. The resource details specific station names, such as _Radio Habana Cuba_, _Deutsche Welle_, and _All India Radio_, alongside their operational times and assigned kilohertz frequencies. It also incorporates a distance calculator, which leverages geographical coordinates to estimate propagation paths, though it notes occasional data inaccuracies leading to transmitters appearing in oceanic locations. The platform's development log highlights continuous updates, including the integration of new seasonal schedules like "A24 frequencies" and "B23 schedule," reflecting the fluid nature of shortwave broadcasting. It documents challenges with geolocation services, particularly concerning Google API changes that impacted distance calculations and required user-side browser configuration adjustments for optimal functionality. The site owner, VAXXi, frequently communicates these technical adjustments and database updates, often acknowledging user contributions and donations. Distinctively, the resource provides a historical perspective through its update archives, illustrating the evolution of shortwave listening over more than a decade since its inception in 2011. It also mentions specific events, such as the BBC adding shortwave broadcasts for Ukraine on 5875 kHz and 15735 kHz, demonstrating its responsiveness to global events impacting broadcast schedules. The site's commitment to user feedback is evident in its bug reporting and feature request mechanisms, contributing to its ongoing refinement.

news and views from the UK about the course of CB in the U.K. and Europe.

This program demodulates the telemetry data signal transmitted by the AO-40 satellite (aka Phase III-D) using the PC sound card

A quick and simple reference to various communications signals, such 10/11 Codes, Morse Code, Phonetic Alphabet, Police Color/Penal Codes, Q-Signals.

Description of the 80m antenna used at CN2WW in the ARRL-DX CW 2007

ARRL Laboratory Expanded Test-Result Report ICOM IC-746 Pro

10 Meter Easy to build wire dipole antenna

Leading supplier of low and high frequency electronic filter design products for the design of wireless telecommunications equipment, semiconductors and more

Free software tests for the Technician, General and Extra class licenses by Shenandoah

March Paddle by K4QU

A moxon antenna project for the 145 MHz

A vertical antenna that can cover HF bands using an UN UN and a fishing pole, usage of tuner is requested.

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.

Welcome to Mike's radio collection, I collect and restore radio sets from the 1930's to the 1960's. I have built up quite a Collection of radios over the years, including Some rare Dutch and German sets.

QRP and Electronic Kits manufacturer

This is a packet radio software developed for amateur radio operators to provide IP communications. You can chat, send/receive e-mail, surf the web and so on via radio depending on your bandwidth. You don't need a TNC. You might have all of TNC features via SoundCard using SoundModem.

Data Management for the RadioShack PRO-93/2053 Trunking Scanner

WV7U's YC156 and 3CPX800 amplifier projects. Everything you wanted to know about using the YC156 or 3CPX800 in a ham radio linear amplifier. See pictures, schematics, test data, links, and more!

Expert Electronics LLC is a manufacturer of modern and compact SDR transceivers. EE develops and produces modern radio-electronic devices based on SDR (Software Defined Radio) for radioamateurs and professional applications. Makers of popular SunSDR models and SunSDR-MB1 transceivers