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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.

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

March Paddle by K4QU

A moxon antenna project for the 145 MHz

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.

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

Shortwave Radio Schedules from Eibi/AOKI combined lists. Includes Google maps showing beam directions and long paths.

This article will help to unravel some of the mysteries as well as giving useful operating tips to maximize your chances of working that rare station

A Working analysis of the gamma match problem that gives useful practical results in a article dated April 1969.

An Off-center-feed antenna that covers 80, 40, 20, 17, 15, 12, 10, and 6 meters

RCKLog is a windows freeware program for logging and administration of SSB and CW-Contest with simultaneous control of transceiver and real-time operation of Packet-Radio.

Cheap Antennas for the AMSAT LEO Kent Britain WA5VJB

Every ham needs an RF power meter. Here is a high performance unit to build at home.

A free to download and print, paper log sheet useful for portable amateur radio operations, in a PDF file.

Design guidelines for Op Amp audio preamplifier circuits by Mike Martell N1HFX

Notes on Axial-Mode Helical Antennas in Amateur Service. Helix Basics, Modeling Issues, and Short Helical Antennas Over Perfect Ground

Transistor and its history and lot of related infos

How to operate on 10 and 20 meters in limited space with this trapped dipole.

N1HFX article on adjustable voltage regulator

A PDF presentation of a home made moxon antenna for 50 MHz 70 MHz and 144 Mhz. The project is mainly out of surplus plastic Plumbing pipes and clips etc, and also details of how the dimensions were calculated.

This document details the design and construction of a Vinecom 6N4 dual-band Yagi antenna for the 50MHz (6-meter) and 70MHz (4-meter) amateur radio bands. The antenna features 9 total elements (4 elements for 50MHz, 5 elements for 70MHz) on a 4.236-meter aluminum boom. Computer simulations using MMANA software predict 7.21 dBd gain on both bands with front-to-back ratios of 16.01dB (6m) and 15.37dB (4m). The design uses 12.7mm diameter elements mounted on a 32mm square boom, weighing 5.7kg total. Practical measurements with an MFJ-269 analyzer confirmed good SWR performance across both bands after element length adjustments.

The document provides a comprehensive overview of baluns, which are devices used to connect balanced loads, like dipole antennas, to unbalanced inputs, such as coaxial cables. It covers various types of baluns, including voltage and current baluns, and their design, construction, and testing. The text discusses the importance of baluns in preventing RF currents on coax shields and their applications in Ham radio setups. It also includes practical advice on selecting and using baluns based on antenna impedance and power ratings, along with detailed performance evaluations and construction tips for different balun configurations.

A 2W 80 meters transceiver assembled into a toaster case.

5 elements Yagi antenna with an 8.7 db gain

If you have space constraint at your QTH for a HF antenna, you can try contructing this HF magnetic loop antenna for 40-20 meters bands

This is a design for a stealthy HF multi-band vertical wire antenna using a tree as a supportby G7AQK

A bowtie antenna is a type of antenna that reputedly provides higher gain at lower radiation angles than a center-fed dipole antenna at heights considerably less than 1/2 wavelength above ground.

2,6 and 10 meters beacon located at Lake White, Ohio

An active receiving antenna for 10 KHz to 20 MHz, a very small sized antenna with excellent performances in noise to signal ratio.

This document contains the detailed instructions to build a homemade lindenblad antenna using a twin-lead as dipole elements. This document contains 9 pages and includes a detailed construction sequence and some drawings to build this antenna for UHF and VHF ham radio bands

Homebrew a compact yagi antenna for 14 Mhz suitable for those with small plots based on a design by AB4GX

A home made yagi antenna featuring 6db forward gain and 22 Db front back

A sourge arrestor for PL 259 connectors. A voltage surge arrestor to limit the voltage that may come back down the wire or coax after there has been static build up

A solutiom for the Ameritron AL-811(H) RF power amplifier, burnt panel meter lights. A common failure with the Ameritron AL-811 and similar amplifiers is that the panel meter lights burn out prematurely. These bulbs are usually integrated into the actual panel meter. The solution for this is to provide the meter backlighting with LEDs.

A 21 MHz Four Square Beam Antenna This popular antenna for the lower bands, can also work well on 15 meters, QST Article

Adding extra directivity to the Moxon Rectangle for 6m, 4, and 2m

Improper grounding or earthing system can cause several unwanted RF interferences (RFI) to television sets, broadcast receivers, hi-fi sets and telephone sets. In this Article the author explain how to setup a proper radio shack grounding using coaxial cable and ceramic disc capacitor

Build this cheap and easy satellite downlink antenna

Service manual in PDF Format for the Yaesu FT-7800 transceiver

An end fed 20 meter half wave antenna

VHF UHF diplexer by G8MNY

A moxon rectangle for 50 Mhz band

Key your transmitter from the tone output of a Morse Code generator program

An 80 meter band vertical loop antenna setup

A Useful Horizontally Polarised Omni-directional Antenna with Gain for 144 MHz

Part 2 You're now much closer to saying goodbye to your unwanted signal problems!

A 2-metre Quad antenna project by K6WXA in PDF file

A PDF presentation about Amateur Radio and Linux by By: Dave Mamanakis. A beginners guide to Linux for radio amateurs, this presentation cover basic concepts of the open source operative system, from the basic installation to the setup of ham radio programs.

A compact antenna for 160 meters, suitable for hams tha want operate top band buh have a limited space

An home made vertical dipole antenna made with simple material. The antenna has a total length of aproximately 16 feet. In this article appeared on June QST 2019, the author explain how he reached the optimal confirugation changing and adjusting the lower part of the antenna, trimming and spacing correctly the copper wire. PDF File to downloas