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A complete guide to undestand and know how electret condensor microphone elements works by K3DAV

Six elements yagi antenna for 6 meters band. This antenna design is based on the QuickYagi 4 software by WA7RAI, uses a 6.5 m boom, feature 12.0 dBi gain and 35dB front/back

winding coils for construction project

BFRA includes LZ callsign search

An home made low pass filter for 70 MHz by IK0VAQ

VHF channel usage, making a mayday call, and related informations

Comparing the ICOM IC-7600 and the Yaesu FTDX-3000

There are many designs for building preamps each with their own advantages and disvantages. In this PDF Article author reviews several different types.

Presents the **BayCom** packet radio system, detailing both its hardware and software components specifically designed for amateur radio use. The resource offers insights into the technical specifications and operational aspects of the BayCom modem, which has been a staple for many German packet radio enthusiasts. It covers the integration of these components within a typical amateur radio station setup, enabling reliable digital communication. Further, the site provides a broader context by including general information about the German packet radio network. This encompasses network topology, operational protocols, and historical developments relevant to packet radio in the region. Users can find details on how to connect to and utilize the existing infrastructure, fostering participation in the local digital amateur radio community.

German contest club

Complete guide to receive weather satelite images with a RTL SDR dongle and free software

1.2 to 30 Volts 1.5 Amps Power Supply

A 160W linear amplifier for 4 meters band based on GI0GDP

The Araucaria DX Group, based in Brazil, functions as an amateur radio club specializing in **DXpeditions**, **contesting**, and organizing various related events. The group actively sponsors contests and provides resources for DX enthusiasts. Its primary focus is on facilitating and participating in long-distance radio contacts and competitive operating events, contributing to the global amateur radio community. The group's activities include coordinating expeditions to rare DX entities, participating in major international contests, and fostering skill development among its members. By sponsoring events, the Araucaria DX Group supports the growth of amateur radio in South America, encouraging participation in competitive operating and promoting the pursuit of DX. The group's initiatives aim to enhance operational proficiency and expand the reach of amateur radio communications.

Popular italian amateur radio forum by ARI Fidenza include a section dedicated to swap and sell

Cushcraft XM240 transformation into a Moxon antenna by W6NL

Kennedy Safaris, cheap,well organized and ham radio friendly

Have you ever thought of setting up a portable HF station for an activity ?

Marshall G. Emm, N1FN, meticulously examines iambic keying, dissecting its historical introduction in the late 1950s with transistorized electronic keyers and its purported advantages. The resource defines keying systems, electronic keyers, and various paddle types, including single-lever and dual-lever paddles, clarifying the distinction between iambic keyers and the iambic sending technique itself. It details the two main types of squeeze keying: true squeeze for alternating dot-dash strings and character insertion for specific elements within a character. N1FN critically evaluates the actual efficiency gains of iambic keying, referencing Chuck Adams, K7QO's, keystroke analysis. While a straight key to bug transition yields a 34.1% reduction and a bug to non-iambic keyer offers 16.1%, iambic keying provides only an 11% theoretical improvement. However, considering typical QSO text and Morse code's inherent optimization for common letters, the practical efficiency gain is estimated at a modest 4-6%. The article also highlights how iambic keying's reliance on precise timing gates can impose a speed limit, making it less effective above 40 WPM, where many operators revert to non-iambic methods or single-lever paddles.

Technical supplement manual of the Yaesu FT-8800R in english

Non-profit public foundation dedicated to providing research and educational access to optical and radio astronomy. Located in Rosman, North Carolina.

Chart that present results of impedance measurements made on a variety of common-mode choke implementations across the frequency range 1MHz to 30MHz by G3TXQ

PDF manual of the TW4040 The Adventurer MonobanderTM TransWorld Antennas

Modification leaves nearly all of the existing Omni agc circuitry intact, simply add an audio detector which modifies the delay characteristics of the original system by G3IXQ

Comparison of all the oscilloscopes available for hobbyists, digital oscilloscopes that you can get for under $500, or oscilloscopes that you can build yourself.

A dual band portable inverted V antenna for 80 and 40 meters band with dimensions for other bands and several assembling instruction

Manual of the BD-35 Dual Band VHF UHF RF power amplifier by Mirage Amp

A presentation of the Yagi Antennas, and other interesting tid-bits by Brian Mileshosky. The document provides an in-depth exploration of the Yagi-Uda antenna, detailing its historical development, design principles, and performance characteristics. Originally described in the 1920s, the Yagi antenna features a driven element and parasitic elements, including reflectors and directors, which collectively determine its behavior. The document highlights how element lengths, diameters, and spacing influence gain, impedance, and directivity. It also discusses the antenna's reciprocal nature and presents data on typical gain values for various element configurations. Additionally, the text covers practical considerations, such as the construction of a "Tape Measure Yagi" for amateur use, and touches on related antenna types like dipoles and their application in Near Vertical Incident Skywave (NVIS) communication.

Arizona near space research - promoting science and education by exploring frontiers in amateur radio and high altitude balloons.

A homemade band pass filter for the 30 meter band based on the original VE7BPO design

Elecraft K3 vs. ICOM IC-781 vs. Kenwood TS-850: comparative Measurements and Experience

Keyclicks and NB modifications for the Yaesu FT-1000MP Mark-V HF transceiver

The Central Arizona DX Association is an ARRL-affiliated club.

How manage and quantify ground loss in vertically-polarized antennas by VE3VN

A custom manual for the Yaesu FT 450 owners, tha includes system controls, factory reset procedure, procedural uses, memory management, programming and many more

Homebrewing portable antennas for field day operations

Activities, legal infos, technical articles, photos, vendors, software, and links

A Personal Museum of Military Radios - Spy Radios - Tubes by Antonio Fucci

Calculate how to set call signs

Home page della Sezione ARI di Gorizia

The Associazione Radioamatori Italiani (ARI) Bergamo section provides a local hub for amateur radio operators in the Lombardy region of Italy. This resource details upcoming events such as the annual _Panettonata di Natale_ and important administrative updates like the 2026 membership renewal process. It also highlights special operating activities, including a commemorative radio activation for the 101st anniversary of the Gleno Dam disaster, which involved operators from both the Bergamo and Vallecamonica ARI sections. The site serves as a central point for local hams to stay informed about club activities and operational opportunities. Members can find information regarding payment methods for annual dues and event schedules. The Gleno Dam activation, for instance, is a significant event, demonstrating the club's engagement in historical remembrance through amateur radio. Such activities foster community spirit and provide opportunities for members to participate in public service and special event operations, often generating **hundreds of QSOs** and promoting the hobby.

Webpage of union de radioaficionados de zaragoza. EA2URE & ED2URE. URZ.

Ari Lecce official web site

Icom IC-51A out of the Box Programming Instructions PDF file by dstarinfo.com

Two different ways to create autotransformer for end fed half wave wire antennas, by using ferrite or air core.

AudioXplorer is a sound analyzer software designed for Mac OSX, provide a real-time analysis window where you can visualize the sound spectrum and sonogram

ARI Macerata Official Web Site

Amateur Radio on the International Space Station european web site

DXpedition by Rene/DL2JRM, Bodo/DL3OCH, Dan/DL5SE, Daniel/DL5YWM & Anett/DO6XX

Maritime Mobile Service Net for disaster help on high seas on foreign lands