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A project to implement a simple and efficient CW Keyer and a side tone generator with Arduino

Pc based test and measurement equipment and instrumentation: digital oscilloscope, logic analyzer and spectrum analyzer.

An interesting presentation of a real multiband Fan Dipole antenna, optimized for better DX operation performances, considering the terrain, position, DX destination path and other influencing factors

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

SkookumLogger is a free contest logging program for Mac OS X 10.7 or later, supporting CW and SSB events on the six HF contest bands plus 6m, 4m, 2m, and 70cm

The resource provides coaxial cable attenuation data, listing signal loss in dB per 100 feet for various cable types across a frequency range from 1 MHz to 5.8 GHz. The initial table details attenuation for cables such as _RG-58_, _RG-8X_, and RG-213, with impedance values of 50 ohm or 75 ohm, at frequencies up to 1 GHz. For example, _RG-58_ exhibits **0.4 dB** loss at 1 MHz and **21.5 dB** loss at 1 GHz per 100 feet. A subsequent table expands on this data, including LMR series cables like _LMR-400_ and LMR-600, along with other types such as 9913F7 and RG214. This section covers frequencies from 30 MHz to 1,500 MHz, also noting the outer diameter of each cable. For instance, _LMR-400_ (0.405" diameter) shows **0.7 dB** loss at 30 MHz and 5.1 dB loss at 1,500 MHz per 100 feet. The final section focuses on VHF/UHF/Microwave amateur and ISM bands, presenting attenuation in dB per 100 feet (and meters) for frequencies including 144 MHz, 450 MHz, and 2.4 GHz. This table includes larger diameter hardline options like 1/2" LDF and 7/8" LDF, in addition to flexible coaxial cables. For example, 1/2" LDF cable demonstrates **0.85 dB** loss at 144 MHz and 6.6 dB loss at 2.4 GHz per 100 feet. DXZone Focus: Coaxial cable attenuation | LMR-400 | RG-58 | 5.8 GHz

NT9K Personal Amateur Radio Website from Melbourne Florida

This is an Arduino-based rotator interface that interfaces a computer to a rotator or rotator controller, emulating the Yaesu GS-232A/B and Easycom protocols which are supported by a myriad of logging, contest, and control programs.

Leader in the development, design, manufacture, marketing and distribution of copper, aluminum and fiber optic wire and cable products for the energy, industrial, specialty and communications markets

Review of the Retevis RT95 also marketed as Anytone AT-778UV dual band VHF UHF FM mobile radio transceiver

SCARA is located in Siskiyou County, CA. Features information on club events, meetings, and membership.

US amateur radio antenna manufacturer. Produce baluns, delta loops, dipoles, ocf antennas and more

Convert any text in morse code mp3 file, you can choose speed from 5 to 50 wpm and tone frequency

Friis-It NF is the first iPhone OS based application that allows you to calculate noise figure, system sensitivity, and cascaded gain for an RF Receiver system

This online project guide details the construction of a homebrew boom microphone system. It details the assembly of a microphone shell from a 3/4" PVC pipe section and an end cap, requiring a drilled hole for a snug fit of the electret or condenser mic element. The internal wiring schematic specifies a **2.2 K** resistor and a **47 uF** polar capacitor for signal conditioning, with a circuit diagram provided for integration with IC-706 series transceivers. The guide outlines the use of CAT-5 cable for internal connections, incorporating strain relief at the rear of the mic shell, and an inline 3.5 mm jack to facilitate an external _PTT_ line, designed for a foot-mounted switch. Further construction involves fabricating a microphone shock mount from a 2-inch PVC connector, detailing the creation of four "fingers" and the insertion of screw-eyes for attaching elastic bands, which are twisted 180 degrees for tensioning and vibration isolation. A foam wind screen is also incorporated into the microphone assembly, secured with adhesive. The boom arm itself is repurposed from an articulated architect lamp, with the original lamp assembly converted into a **60 watt** resistive load for testing power sources. Microphone cabling is secured to the boom arm using wire ties, ensuring sufficient slack at hinge points to maintain articulation. The boom base is mounted to a bookshelf, requiring specific positioning to achieve proper microphone placement in front of the operator. Performance evaluation of the microphone system is conducted through on-air audio signal reports from other amateur radio operators. DXZone Focus: Online Project Guide | Boom Microphone Construction | Electret Mic Element | PTT Line

Homebrewing special insulators with PVC and copper corona rings

The Dilawri Cardiovascular Institute (DCI) is a prominent Canadian organization dedicated to advancing cardiovascular health through cutting-edge research, equitable patient care, and medical innovation. It integrates 16 core centers, including specialized units like the Centre for AI, Data Science, and Imaging, and the Centre for Heart Rhythm, to bridge research findings directly into clinical practice. Their mission emphasizes providing world-class cardiac care accessible to all patients, regardless of their geographic location, by employing disruptive innovation and creative strategies to reach individuals faster. The institute focuses on a team-based approach, ensuring patients receive the correct therapy at the optimal time for long-term well-being. DCI's commitment extends to continuous growth through education, pushing boundaries beyond standard care, and fostering a respectful, inclusive environment for both staff and patients. They lead industry collaborations to shape the detection, treatment, and management of heart disease.

Constructing a compact directional antenna for the 17-meter band, this resource details the build process for a Moxon rectangle, a two-element Yagi variant with folded-back elements. It covers the antenna's evolution from the _VK2ABQ beam_ and provides specific dimensions for a version built using fishing pole whips. The content includes a discussion of the antenna's radiation pattern, feedpoint impedance, and its inherent front-to-back ratio, which is often superior to a standard two-element Yagi. Practical considerations for element spacing and material choices are also addressed, alongside a visual representation of the antenna's physical layout. Performance data presented includes a comparison showing the Moxon rectangle's **2.5 dB gain** over a half-wave dipole and a front-to-back ratio of **20 dB**. The resource also touches upon the antenna's relatively wide bandwidth for a two-element beam and its suitability for portable operations due to its compact footprint. It offers insights into optimizing the design for specific operating conditions and discusses the advantages of its lower take-off angle compared to omnidirectional wire antennas, making it effective for DX contacts on the 17-meter band.

A mini Dxepidition to Piel Island on 24th/25th of May 2008 by the CQ CQ Portable group and the call sign will be GB0PIA.

Latchways are the world leaders in fall protection and the manufacturers of the mansafe range of products for working at height.

New Zealand Radio DX League

Rigpix page on the YAesu VX-6R include link to Yaesu VX-6R Manual

A 70 MHz QRP transverter project

About SSB Audio by N4KC

Whether you're teaching a ham radio class or studying for your license on your own I hope you find this website useful.

30 meters beacon from UK. QRSS is a method of sending very slow morse code.

This article deal with various means to covertly operate radio systems while going unobserved.

West Georgia Amateur Radio Society, Inc

KK5DR review of the IC-7700 HF ICOM Transceiver

Operating the AO-51 amateur radio satellite with a handheld transceiver (HT) presents a practical entry point for newcomers to satellite communications. This resource details the necessary steps and considerations for making basic contacts, focusing on accessible equipment. It covers fundamental concepts such as _Keplerian elements_ for satellite tracking and the importance of understanding Doppler shift effects on both uplink and downlink frequencies. The tutorial outlines a straightforward approach to satellite passes, emphasizing the use of readily available gear. It provides insights into antenna orientation and timing for successful two-way communication. The content aims to demystify satellite operation, enabling operators to achieve their first **AO-51** contacts with minimal specialized equipment. Key aspects include frequency management and basic operational techniques.

Link page to all kinds of packet radio related sites

Investigates the legal framework surrounding **pneumatic antenna launchers** in Victoria, Australia, specifically their classification under the Firearms Act 1996. The author, VK3KBC, details how these devices, designed to discharge a projectile by compressed air, are defined as 'firearms' and subsequently categorized as **Category E Longarms**. This classification carries significant penalties for unregistered possession or use, with the author noting the lack of provisions for amateur radio operators to legally possess and use such devices for antenna deployment. The author shares personal experiences needing such devices for portable HF radio operations, contrasting them with previously legal slingshots and current alternatives like kites or bow and arrow. VK3KBC outlines efforts to advocate for legislative change, including submissions to the Wireless Institute of Australia (WIA) and the Victorian Department of Justice, proposing an amendment to Section 3(i) of the Firearms Act 1996 to include amateur radio field operations as an exempted use. The resource also reviews the original intent of the Category E firearm classification, suggesting that pneumatic antenna launchers may have been assigned this category in the absence of a more suitable alternative.

Microwave antennas, cables, connectors, accessories

Demonstrates the _RoMac Automatic CW Identifier 2012_ software, a Windows application designed to automate station identification and provide a tuning pulser. It can send CW identification via a sound card's audio output or by keying a radio's manual CW jack using a serial port's DTR line. The software also supports CAT commands for various Kenwood, Yaesu, Flex, and Elecraft radios, enabling automatic mode and frequency changes for ID transmission. It integrates with USB audio-capable radios like the Icom 7300 and Yaesu FT-991, simplifying connectivity with a single USB cable. The application features a fully programmable interface, adjustable CW speed from **5 to 35 WPM**, and ID intervals from **5 to 30 minutes**. The integrated "Pulse Tuner" function allows for safe amplifier and antenna tuner adjustments by sending short audio tones or rapid CW keying, with an adjustable duty cycle from 1% to 100%. It offers compatibility with a wide range of transceivers and amplifiers, and a schematic for a basic sound card interface is included for users without existing setups.

When I tell friends that I enjoy amateur radio contesting, their reaction is usually a quizzical stare. "What's that?" It is hard to explain in the span of a cocktail conversation, so here is the answer.

Ten-Tec groups at Yahoo!

A review of the chinese QRP HF transceiver X1M SSB/CW RTX

This code practice oscillator project uses a 555 timer IC. Includes a Schematic Diagram of the morse code oscillator

Charlie Papa India RhAne-Alpes & Bourgogne HQ

Forget about spending expensive time and big money for QSL cards printing, filling out, sorting and sending. Exchange QSL information system.

Amateur radio repeater scanner at Pomona California

The 7-minute, 52-second video, published on December 31, 2016, by TheStingyHam, details several methods for optimizing receive audio on the **Elecraft KX2** QRP transceiver. It specifically addresses challenges encountered on the 40-meter band, a common haunt for QRP operators, while also noting that 15m and 20m operations might benefit from different settings, such as combining the preamp with receive EQ and RF gain adjustments. Key moments highlighted in the video include specific adjustments for noise reduction, filter settings, signal attenuation, and receive equalization. These techniques are demonstrated to help operators extract clearer signals from a noisy band, a critical skill for successful portable operations and DXing with low power. The author, drawing from field experience, suggests that while the tips are primarily aimed at 40m, the underlying principles of careful audio and RF gain management are broadly applicable across the HF spectrum, enhancing the overall QRP operating experience.

An open design exercise in interface archaeology, that decodes the input from a classic Morse key to send twitter messages

Zeus Radio program is designed specifically for the ZS-1 transceiver and supports all the basic functions (RIT, XIT, SPLIT, Noise Reduction, Auto Notch Filter, etc.) in order to work in the broadcast brought only pleasure. Zeus Radio works also with Hermes, Anan, Afedri, Red Pitaya, HiQSDR, Odyssey, Extio, RTL-SDR, Peaberry, Winradio, SDR-IQ, Afedri

The dipole shown in this document is installed in an inverted Vee configuration, with two leg elements on each side held parallel to each other by 21cm spacers. The upper leg is for 40m and the lower leg for 20m. The spacers are made of 7mm plastic garden hose support for garden sprayers cut to 21cm.

Search the online log for 9X0T 9X0Y DX Peditions 2018

Digital multimeters, power supplies, frequency counters, RF analyzers, signal generators

Javascript filter design page with introduction to low pass filters by k7mem

Some modifications for the Tigertronics Signalink USB sound card radio interface

Build a Power Source for Portable Ops that will last a while by n1gy