Search results

The Alcorn County ARES group provides crucial **emergency communications** support within Alcorn County, Mississippi, operating under the Amateur Radio Emergency Service framework. This organization mobilizes licensed amateur radio operators to assist public safety agencies during emergencies, natural disasters, and other critical events when conventional communication infrastructure fails or becomes overloaded. Their activities include regular training exercises, participation in local drills, and maintaining readiness to deploy communication assets. Members engage in various aspects of amateur radio, including voice, digital modes, and message handling, ensuring a robust and redundant communication network. The group's focus on preparedness and community service aligns with the core principles of ARES, emphasizing rapid response and effective information relay during crises. They often collaborate with local emergency management agencies, such as the Alcorn County Emergency Management Agency, to integrate amateur radio capabilities into broader disaster response plans. Dustin Brumfield, KD5LAP, serves as the Public Information Officer, facilitating outreach and coordination. The club's operational area is specifically Alcorn County, Mississippi, contributing to local resilience.

Elk Antennas to give the Ham log periodic antennas with the best gain, directivity, and front to back ratio possible for the size and price.

PhaseFree, Inc. Surge Suppression. Provide customers with the safest and highest quality surge suppression on the market. Providing surge suppression for the Navy's MARS stations protecting their investment.

Presents field test results for an **elevated SuperAntenna MP-1** portable antenna, configured on a tripod for HF operations. The resource details the antenna's setup and performance during a portable activation, focusing on its use across the 40-meter, 20-meter, and 17-meter amateur bands. It includes observations on signal reports and operational considerations for this specific portable antenna configuration. The content provides practical insights into deploying the MP-1 antenna in a non-ground-mounted setup, which is often a point of interest for portable and QRP operators. It documents the author's experience with the antenna's tuning and effectiveness for making contacts under real-world conditions, offering a user-perspective review of its capabilities. The article also features photographic evidence of the antenna's deployment, illustrating the tripod mounting and the overall portable station setup.

Observing how fractal antennas might exhibit characteristics that are correlated to their form by kb7qhc

A public service amateur radio club. Haverhill, Massachusetts

LA3ZA on magnetospheric ducting as an explanation for delayed signals on 3.5 MHz

OpenHamClock is a modern, open-source dashboard for amateur radio operators, designed as a web-based successor to the original HamClock. Deployable locally on a Raspberry Pi or via the cloud, it centralizes essential DX operations into a single, intuitive interface. At its core is an interactive world map that visualizes real-time DX spots, signal paths, satellite tracking, and POTA activators. The software seamlessly integrates critical tools like WSJT-X, DX Cluster, and PSKReporter for monitoring digital traffic. Additionally, it provides vital environmental data, including real-time space weather indices, solar activity, and personalized HF propagation predictions. With customizable themes and a modular architecture, OpenHamClock offers modern operators comprehensive, at-a-glance situational awareness of global radio conditions

The Waterville Area Wireless Association was founded in 1957

The correct procedure for measuring SSB PEP (Peak Envelope Power), using an oscilloscope with a vertical bandwidth of at least 20 MHz, or a monitor scope.

Amateur radio antenna maker with online shop based in Brazil

Listen to online police scanner from Douglas County in Oregon USA

The N1HFX thermal cooling fan controller project details a practical circuit designed to manage cooling fan operation based on temperature, a common requirement for high-power amateur radio equipment. This build utilizes a **LM34** temperature sensor, providing a linear voltage output directly proportional to Fahrenheit degrees, simplifying the control logic. The circuit's core functionality involves a comparator that activates the fan when a preset temperature threshold is exceeded, ensuring efficient cooling and reducing unnecessary fan noise. This controller is particularly useful for amplifiers, power supplies, or transceivers that generate significant heat during operation. The design incorporates a _TIP120 Darlington transistor_ to drive the fan, capable of handling up to 5 amps, making it suitable for a range of fan sizes and current requirements. Field results indicate stable temperature regulation, preventing thermal runaway in enclosed environments. Construction involves readily available components, making it an accessible project for hams looking to optimize their station's thermal management.

The KI7CX 2.4 GHz Cheap & Easy antenna/feed

Ham and Amateur Radio Swap - Buy, Sell, Trade, Swap, radios, amplifiers, antennas and more. Classified ads for Canada, Ontario, Quebec, Maritimes, Prairies, British Columbia and USA

Free ads for UK Hams

The MFJ-971 portable antenna tuner, as stock, lacks a bypass switch and sufficient inductance for efficient 1.8 MHz operation. This modification addresses these limitations by integrating a DPDT switch for direct signal bypass, enhancing operational flexibility. Furthermore, the guide details the addition of a T130-2 iron powder toroid, wound with **29 turns** of enamelled copper wire, to augment the tuner's internal inductance. This increases the maximum inductance from approximately 17µH to around **27µH**, enabling effective impedance matching on the _160-meter band_. The modification involves cutting the wire after the 'L' tap on the original inductor and inserting the additional toroid, ensuring the entire original coil plus the new inductance is engaged when 'L' is selected. This preserves the functionality of other inductance settings while extending low-band performance. The article also highlights a potential RF burn hazard from the variable capacitor nuts on the MFJ-971, even at QRP power levels.

Dedicated to Promoting Activity, the State of the Art in Equipment Design, and the Exchange of Ideas and Technology for the Amateur Bands Above 902 MHz

Experiments with Balloon and Kite Lifted Antennas bby G4VGO

Home made LF converter, listen to signals below 300 KHz

A classic document originally presented in Proceedings of the Institute of Radio Engineers in 1937 and is, still today, the standard referenced by the FCC, text books and many amateur radio publications.

Lockheed martin recreation association amateur radio club

Official web site of the Alaska QRP Club The AK/QRP Club is dedicated to the enjoyment of low power Amateur Radio operations.

This is a new club serving the Henry County area.

This air-powered Tennis Ball launcher is designed to launch tennis balls over trees towing fishing line.

Picture gallery of VR2IO morse keys

About antenna or aerial resonance and bandwidth and the impact of RF antenna resonance and bandwidth on radio communications systems.

AP Sprint Contest

Switching Regulator Basics By Mike Martell N1HFX

Utility-Driven Tradeoff Analysis, if you want to geto on the microwave bands , you will have to choose the proper antenna for your operating conditions. How to decide is not always easy, and you may also decide to build your own antenna.

Article on antenna feed impedance and the importance of matching RF andtennas to feeders, including notes on Radiation resistance, loss resistance, and efficiency are also detailed.

Ham radio for people with disabilities. A weekly podcast from the Courage Handiham System

Constructing a high-performance RF spectrum analyzer up to 1000 MHz requires careful attention to component selection, shielding, and circuit isolation. This resource details a project that improves upon the _Spectrum Analyzer for the Radio Amateur_ design by Wes Hayward (W7ZOI) and Terry White (K7TAU), incorporating ideas from Scotty Sprowls' project, particularly his 1013.3 MHz IF bandpass cavity filter. The analyzer utilizes a Mini-Circuits SRA-11 mixer with a sweeping local oscillator from 1013 to 2013 MHz, feeding into a 4-pole copper pipe cavity filter. The design employs a second SRA-11 mixer with a fixed 1024 MHz LO to produce a 10.7 MHz final IF. This signal then passes through narrowband resolution filters and is processed by Analog Devices AD603 and AD8307 ICs for IF amplification and logarithmic detection, driving an oscilloscope in X/Y mode. The project emphasizes modular construction, using salvaged components and double-sided FR4 material for PCBs, with critical notes on minimizing spurious images through effective shielding and proper voltage regulation for each module. Key components include a Z-Communications V585ME48 VCO for the first LO and a Z-Comm V583ME01 VCO controlled by a Motorola MC145151 PLL for the second LO. An optional Hittite HMC307 step attenuator and K&L 5L121-1000/T5000-O/O low-pass filter manage RF input. Tuning procedures for the 10.7 MHz IF resolution filter are also detailed, showing before-and-after spectrum views.

The No-Nonsense Extra Class License Study Guide (for tests given between July 2016 and June 2020) This is the study guide you want if you want to pass the Extra Class exam

Features an immense gallery of color photos, facts, newsletters, articles and links for those interested in collecting or restoring antique radios

The Triangle ATV Association is an organization of hams in the Raleigh-Durham-Chapel Hill NC area who communicate by means of our own personal TV transmitters and receivers.

The YASME Foundation is a not-for-profit corporation organized to conduct scientific and educational projects related to Amateur Radio, including DXing and the introduction and promotion of Amateur Radio in underdeveloped countries.

The short history of the SSN Smoothed Sunspot Number at Luxorion

Circuit designs for IC audio amplifiers by N1HFX

Radioing Collins Radio collection

A Scientific endeavor aimed at studying the properties and behavior of the ionosphere.

Operating where independent media is suppressed, _Radio Free Europe/Radio Liberty_ (RFE/RL) delivers news and information in 27 languages to audiences in 23 countries. This resource primarily functions as a news portal, focusing on geopolitical events, regional conflicts, and human rights issues, particularly in areas like Ukraine, Russia, Iran, Afghanistan, and Central Asia. It features articles, videos, podcasts, and photo galleries, covering topics such as international relations, energy politics, and the impact of conflict on civilian populations, often highlighting the perspectives of local journalists and freelancers in challenging environments. The content frequently addresses the operational context of shortwave broadcasting, though the site itself is a digital news platform. For example, it details the implications of long-distance strikes and regional military capabilities, which are relevant to understanding the strategic importance of various communication methods. The resource also provides insights into the challenges faced by populations in areas with limited access to uncensored information, underscoring the role of independent news organizations in providing alternative narratives.

An antenna system is electrically small if it's enclosing sphere is <&#955;/2&#960;. So a 10m band antenna of under 1.6m long qualifies.

The Rockwall County Amateur Radio Club is a made up of a group of Amateur Radio operators in and around the Rockwall, Texas area.

Showcasing a diverse portfolio, RF Industries specializes in interconnect solutions crucial for modern communication infrastructure. Their product line encompasses a wide array of RF connectors, precision-engineered coaxial cables, and robust data cables, all designed to meet the rigorous demands of wireless and wireline telecom, data communications, and industrial applications. The company emphasizes its role in "Connecting the Next Generation" by providing foundational components for evolving network technologies. Their offerings extend beyond basic components to include comprehensive installation and test kits, alongside various adapters and wire harnesses. This focus ensures that their products not only perform reliably in the field but also integrate seamlessly into complex systems, supporting critical infrastructure. RF Industries' commitment to quality and innovation positions them as a key supplier for those building and maintaining advanced communication networks, from _5G deployments_ to industrial control systems, ensuring signal integrity and robust connectivity.