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Learn to recognize Morse code at 25 WPM and not memorize DITs and DAHs at 5 WPM. This app will train you to hear and send Morse code at 25 WPM using an approach very similar to the Koch method.

An homemade 50 Ohm 140 W dummy load based on an idea and project by ON5DB Renaud.

This article is about two excellent small helical antennas for the two meters band. With performance close to that of full sized antennas, these small helical antennas are low in profile but high in efficiency.

This EXCEL Program Worksheet calculates the safe operating conditons for a toroidal transformer operating between 1 and 50 MHz. Manufacturer data for complex permeability, magnetic dimensions, and saturation flux density must be available. Some core types which are commonly used in amateur transmission are included. The program produces limiting winding voltages for linear operation and temperature rise over the range of frequencies and power specified.

An Android based CW practice program based on simulated QSOs. The app will generate Morse code sounds from 5-50 words per minute.

The page provides information on a simple 50MHz J-Pole Antenna project based on the DK7ZB design. It explains the principle of the Wireman-J-Pole, the feeding process, practical mounting, and simulation results using MMANA GAL. The content aims to guide amateur radio operators in building their own J-Pole antennas for the 6-meter band.

If you thought you knew everything about balun performance characteristics, there is an important figure of merit you may have neglected

Internal Bluetooth interface for miniVNA, Bluetooth connection to the PC allow Full cordless operation with ao external components

A Combination CW Keyboard and Paddle Keyer. It uses a single Atmel microprocessor, the ATmega328P from the AVR family, and a 4 row by 20 column LCD display module.

Malaysia World JOTA

This project describes a DIY all band HF SDR transceiver. Built around a Softrock 6.3 kit, it boasts a 20W homebrew amplifier and ATmega168 microcontroller for USB control. An LCD displays frequency, power, and SWR. Automatic LPF selection and SWR protection enhance functionality. Compatible with Rocky and PowerSDR software, this project provides a cost-effective and powerful HF SDR transceiver for hobbyists.

Northern Michigian Amateur Radio Club Inc. was founded on the principles of providing services to the local area Amateur Radio Service Groups and to public.This group of license amateur radio operator provide Emergency Communication during the time of weather related,disasters and man made emergencies.

Yea Cabrillo2Adif is a free software for converting the radio logs from Cabrillo to Adif log format for MacOSX

Receive and decode SSTV amateur radio SSTV signals with this small and powerfull SSTV decoder app for Android devices. Requires access to microphone.

This is a synopsis of a talk presented to the Sydney VHF DX GROUP by VK2ZAB on how, when and why is convenient to build a Yagi antenna stack.

This article aims to help promote the proper configuration for having a clean signal on the waterfall to avoid interference to other users and also to vastly increase the effectiveness of your signal.

Article on operating aids and band usage during solar minimun periods. Author tries to explain what can we expect on the HF bands during a solar minimum period and which approach to be used to understand band openings.

Guide to the Yaseu VX5r, Modes, Memory Banks, Buttons, SET commands, How to save a memory, Tricks and Memory Channel Listing

A 18 elements Yagi antenna for 432/435 MHz as published on 2011 CQ VHF magazine

Schematic drawing and instructions for the construction of a simple portable dipole for use in low power and portable operations

A rotary dipole antenna for 30 meters band. Each arm is about 12.5 ft and is constructed from telescoping fibreglass flag/fishing poles and short lengths of aluminium tubing. Two short lengths of glass-fibre rod were used to insulate the arms from the supporting hardware.

W3FF, N7UN, WD9CMD, N7BF, WF2S, K9CJM,AA4OC, WU1B December 2011

Adapting a common PC earphone with microphone to connect to a transceiver via a homemade pre-amplifier, using a simple chip with aprox 10 db gain. Includes a schematic diagram

Complete plan for making a 2-meter J-Pole antenna. This drawing in PDF File includes a detailed list of the parts needed to assemble the Jpole antenna for 144 MHz.

The project in this article illustrates how to do this in a simple and low cost way so that you can easily access the microwave bands using the existing HF or HF/VHF transceiver as IF.

Have you been looking for an easy way to measure power or SWR at 1296 MHz? One thing is certain, it is not easy - simply because the normal range of SWR meters that most of us have is not up to 1300 MHz.

This resource provides a historical analysis of amateur radio call sign assignment policies in the United States, detailing regulatory shifts from the Department of Commerce to the Federal Radio Commission (FRC) and subsequently the Federal Communications Commission (FCC). It documents the evolution of call sign issuance, from early reissuance practices in the 1920s to the implementation of the Group Call Sign Assignment System on March 24, 1978. This system categorized call signs (e.g., 1x2, 2x1, 1x3, 2x3 formats) into groups A, B, C, and D, correlating with license classes such as Extra, Advanced, General, and Novice, and specifying prefixes for contiguous U.S. and territorial areas (e.g., _AH_, _KP_, _KL_). The document further details the legislative process leading to the modern Vanity Call Sign program, initiated by a petition in June 1990 and formalized by the Omnibus Budget Reconciliation Act of August 10, 1993. It outlines the FCC's adoption of final rules on December 23, 1994, and the subsequent fee structure, with the first vanity call sign issued on May 31, 1996, at a cost of **$30.00** for a ten-year term. The ARRL's proposed "starting gates" implementation strategy is also described, which phased in eligibility for vanity call signs based on license class and prior holder status. DXZone Focus: Historical Document | Regulatory Analysis | Call Sign Formats | Fee Structure

PSK Reporter,is a powerful tool for monitoring your FT8, JT65 or PSK signals around the world. But, even if you are not transmitting on any of these modes it can still be a great propagation tool for determining which bands are open and to where in the world signals from your area are being heard.

This is a compact three transistor regenerative general coverage receiver with fixed feedback. The sensitivity and selectivity is relative good, especially on the LF and MW bands, as can be expected with this simple design.

Presentation of the QO-100 the first geostationary OSCAR from Qatar by AMSAT-DL

Mini-Operating Guide includes useful hints on Using the HM-133 Microphone, Basic Operation, Operating through a Repeater, Programming a Memory Channel and Assigning a Memory Channel to a Memory Bank

This magnetic loop DIY site is ment to be an introduction into making DX high quality magnetic loop antennas that will beat any dipole

CERT Communications Team Procedures Alinco DJ-191 quick reference in a four pages PDF file

Free Windows program intended to be used as a training aid for sending CW using an iambic Winkeyer from K1EL Systems. Iambic Master operates as a game. The objective of the game is to send the text in the Target box as accurately as possible.

Complete microphone wiring handbook for most popular radio transceivers provided by Astatic Microphones.

A collection of 450 MHz Cheap Yagis that have proven great portable operations, back-packing and transmitter hunts, and are something inexpensive you can throw up in the attic for that weak repeater

Although most Preselectors are designed with an internal T/R relay, theoretically enabling direct insertion between the transceiver and the antenna, there is a problem when running CW, especially when running full QSK. The switching time of the internal relay is too slow to follow full QSK. The best way to avoid this problem altogether is to insert the Preselector directly into the transceiver’s RX antenna line, thus avoiding entirely the need to switch the Preselector in and out.

All available frequencies & offsets configurations for repeaters can be downloaded as database for Kenwood MCP-2A memory channel programming software for TM-D710 & TM-V71. Zip file is no more available from the author, but the full table of frequencies is still online

This free app encode pictures in Slow Scan TV SSTV signals. Support the most popular modes Martin 1, Martin 2, Scottie Modes, Robot and Wraase modes. Image editing is even possible with som text overlaying features

An inductance and capacitance meter, measuring range is from 0 to >0.1uF for capacitance and 0 to >10mH for inductance. A project by Phil Rice, VK3BHR

A homemade morse code decoder project, providing a detailed schematic and pictures

Have you ever thought of setting up a portable HF station for an activity like the Field Day ?

Operating on Airplane scattering. Scattering of radio signals by airplanes. An introduction to operating ariplane scattering, using aircraft to redirect RF that would otherwise be lost in space. Antenna Pointing, Doppler Shift/Digital Modes, using digital modes to operate airscatter.

The Icom IC-7300 is a popular SDR transceiver known for its excellent performance in ham bands. However, users have reported issues with reception reliability outside these bands due to ADC aliasing. This phenomenon occurs when the sampling rate of the radio interacts with frequencies outside the intended range, leading to unwanted signals being received. For instance, when tuned between 30 to 36 MHz, users may inadvertently pick up WFM broadcast signals or PMR communications due to aliasing effects. This guide outlines modifications to improve the IC-7300's performance by addressing the low-pass filter design, which is crucial for reducing interference from these unwanted signals. The proposed modifications involve adjusting the low-pass filter on the PA unit to better attenuate frequencies that cause aliasing. Measurements indicate that the original filter design allows significant signal leakage, leading to false receptions. By implementing the suggested changes, users can achieve a notable reduction in unwanted signals, enhancing the overall functionality of the IC-7300. While the modification requires careful soldering, the benefits in performance make it a worthwhile endeavor for serious operators looking to optimize their SDR experience.

This presentation applies to HF / VHF / UHF antennas and is about 14 different type of antennas suitable for indoor od apartament installations

An explanation of the different procedures and definitions that are commonly used for blocking dynamic range (BDR) measurements. Dynamic range in general is the ratio between the weakest signal a system can handle and the strongest signal the same system can handle simultaneously without an operator switching attenuators or turning volume potentiometers

This is a very small vertical 160m antenna that fits in the loft of even my small house. It was built as a way of getting a signal out on 160m for local AM contacts, but the local noise level was far too high to allow it to be used at night for this purpose. However, on WSPR it did a pretty good job with WSPR spots from a very long way across Europe being received when running 2.5W out.

This morse key and buzzer design only requires parts that one may already have or are easy to find on the web. There is nothing critical except that the contacts must meet when the key is depressed.

A document that will guide you on Coaxial-Cable trap optimization process to gain on global antenna performance and on increasing effective bandwidth.

Experimenting with capacitive antennas for 40 and 80 meters band. A very space-saving antenna with good receivings caracteristics