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Determining the actual need for an antenna tuner often hinges on the specific antenna and feed line configuration in use. While many hams believe a tuner is always essential, its primary role is to present a 50-ohm impedance to the transceiver, not to "tune" the antenna itself. For instance, a resonant dipole fed with _coaxial cable_ at its design frequency typically requires no tuner, as the feed line impedance closely matches the radio's output. However, operating a non-resonant antenna, or using a resonant antenna on multiple bands, frequently necessitates a tuner to manage high Standing Wave Ratio (SWR) on the feed line. The article clarifies that a tuner placed at the transceiver only matches the radio to the feed line, not the antenna to the feed line. For maximum efficiency with a non-resonant antenna, an _automatic antenna tuner_ (ATU) or a remote tuner placed at the antenna feed point is often more effective, minimizing losses in the feed line. The discussion also touches on the practical implications of SWR, noting that modern transceivers often fold back power at high SWR, making a tuner a practical necessity to achieve full output power, even if the antenna itself is not perfectly matched.

RemoteHams.com permit to display and control transceivers all around the world

The Q-signal **QRP** signifies a request to reduce power, and in amateur radio, it defines operating with 5 watts or less for CW and 10 watts or less for SSB. This article addresses common inquiries from new hams regarding the practice, its benefits, and implementation methods. It explains how a 5-watt QRP signal, compared to a 100-watt signal, typically results in only a 13dB drop in signal strength, equating to about two S-units, still providing solid copy under most conditions. Hams choose QRP for various reasons, including seeking a greater challenge in DXing or contesting, reducing band interference, or enabling portable field operations with lightweight, battery-efficient equipment. A modern single-band CW transceiver, key, and antenna can fit into a pocket, offering receiver performance comparable to commercial rigs and extended operation on a small battery. This portability facilitates operations in remote locations where higher-power setups are impractical. Operating QRP can involve simply reducing power on an existing commercial HF rig or building a dedicated QRP transceiver from a kit, such as the **Wilderness Radio SST** with its 2-watt output and 15mA receive current draw. While SSB is viable, CW remains the most popular and efficient mode for QRP due to its superior signal-to-noise ratio. The article lists common QRP calling frequencies across 160m through 10m bands for both CW and SSB, and highlights organizations like QRP ARCI and NorCal that support the QRP community.

The resource provides an interactive map interface for locating amateur radio license holders across the United States. Users can input a _callsign_, _gridsquare_, zip code, or street address to center the map, which then dynamically populates with station markers. This functionality allows for precise geographical searches, revealing the distribution of hams within specific areas. Upon initial search, the map renders with adjustable zoom and pan capabilities. A key feature is its automatic reload mechanism: after two seconds of inactivity, the map updates to display stations within the newly viewed area. This ensures that the displayed data remains relevant to the user's current focus, whether exploring a densely populated urban center or a more remote region. Further interactive elements include clickable gridsquare labels, which re-center the map, and a "Show gridsquares" checkbox for toggling grid line visibility. Clicking on individual station markers reveals a popup containing the licensee's name and address information, making it a practical tool for geographical station identification.

Monitoring extremely weak signals in the QRSS (Very Slow Morse) mode requires specialized receiving and processing capabilities to extract information below the typical noise floor. This project provides a software solution, _QrssPiG_, designed to run on a Raspberry Pi, enabling it to function as a dedicated QRSS grabber. It interfaces with various Software Defined Radio (SDR) devices, including the popular _rtl-sdr_ dongles and _HackRF_ units, to acquire raw I/Q data streams. The software then performs the necessary signal processing to visualize and decode these faint, long-duration CW transmissions, often operating with milliwatts of power. The system leverages the computational power of the Raspberry Pi for real-time signal analysis, allowing hams to participate in QRSS experiments and monitor distant beacons. It supports different SDR hardware, offering flexibility in setup and deployment for home stations or remote monitoring sites. The project includes detailed instructions for installation and configuration, making it accessible for those familiar with Linux environments. This grabber is particularly useful for tracking propagation on the LF and HF bands where QRSS activity is common, providing a visual representation of signal presence over extended periods.

Documents the _5W0M_ DXpedition to Samoa (IOTA OC-097) conducted by a German team from April 4th to 18th, 2013. The resource provides operational details and insights into activating this Pacific entity. It covers the planning, execution, and on-air activities of the multi-operator team, focusing on maximizing contacts across various HF bands. The expedition successfully logged over **30,000 QSOs**, providing DXCC credit for many operators worldwide. The site serves as a historical record, allowing hams to review the expedition's progress and understand the logistical challenges of operating from a remote island. It highlights the strategic band choices and operating techniques employed to achieve a high QSO rate and reach diverse geographical areas.

Documents the XR0ZR DXpedition to Juan Fernandez Island (SA-005) in November 2013, providing insights into activating a highly sought-after DXCC entity. The team's efforts focused on maximizing QSO opportunities across various bands and modes, a critical aspect for stations aiming to complete their DXCC or IOTA awards. Operating from a remote location like Juan Fernandez presents unique logistical and technical challenges, which the expedition successfully navigated to put this entity on the air for thousands of eager DXers worldwide. The resource outlines the operational period, the callsign XR0ZR, and the specific island group activated. Such DXpeditions are vital for the global amateur radio community, enabling hams in less accessible regions to achieve their award goals and fostering international communication. The detailed account serves as a historical record of a significant activation.

Remote viewing can be useful for Hams, in example remotely viewing antennas during a storm.

Monitoring radio communications through web-accessible Software Defined Radios (SDRs) has become a popular facet of the hobby, and Receiverbook serves as a centralized directory for locating these remote assets. The platform aggregates listings for both **OpenWebRX+** and **KiwiSDR** installations, providing a gateway to a diverse array of frequencies and operating modes. My own experience with similar directories highlights their utility for casual listening, DXing, and even troubleshooting local RFI by comparing signals across different geographic locations. The directory details specific receiver locations, from Bedford, England, to Marahau, New Zealand, and Berlin, Germany. Each entry often specifies the supported frequency ranges, which can span LF, MF, HF, VHF, and UHF bands, including dedicated segments like 80m, 40m, 2m, and 70cm. Many listings explicitly note support for HAM radio, broadcast services, and public two-way radio, making it a versatile tool for various listening interests. Beyond general frequency coverage, some entries provide granular details about the underlying hardware, such as the **SDRPlay RSP1A** or RTL-SDR Blog V3, and even the antenna types employed, like the Sirio Gain-Master. This level of detail is invaluable for serious SWLs and hams looking to understand the capabilities and limitations of a particular remote receiver before tuning in.

This page explores the world of Software Defined Radios (SDRs) in the context of amateur radio. It discusses how SDRs have revolutionized the hobby by reducing costs and enabling remote operation. The article provides ideas for projects and experiments that hams can undertake with SDR technology, highlighting the educational and experimental opportunities it offers. It also mentions specific examples of SDR projects like the Stoke on Trent SDR and SDR.HU. The content is aimed at amateur radio operators looking to explore and harness the potential of SDRs in their stations.

Receiving Digital Amateur Television (DATV) signals requires specialized software to interface with hardware tuners and decode the video stream. The _MiniTioune_ software, developed by F6DZP, serves this purpose, providing a Windows-based application for DVB-S and DVB-S2 reception and analysis. It is designed to work in conjunction with _MiniTiouner_ hardware, enabling hams to monitor DATV transmissions, including those from the QO-100 geostationary satellite. The resource outlines the initial setup process, including connecting the MiniTiouner hardware via a high-quality USB2 mini cable and running diagnostic test software. It details how to configure essential parameters such as symbol rate (SR), FEC rate, and DVB mode for various signal sources, from domestic satellite dishes to local DATV transmitters. Troubleshooting steps for common issues like "no video displayed" are also provided, often pointing to corrupted software filters or incorrect _Auto PID_ settings. Advanced features like the Web monitor for remote signal reporting and integration with _VLC_ media player for more tolerant decoding of non-DVB compliant signals are covered. The document also references a comprehensive user guide by W6HHC for the _MiniTiouner-Express_ system, which utilizes the same software, offering further in-depth assistance for operators.

Demonstrates firmware for microcontrollers like the _ESP32_ to implement a LoRa APRS iGate and Digipeater. This project leverages LoRa for packet radio communication, allowing amateur radio operators to bridge the gap between LoRa-enabled APRS stations and the global APRS-IS network via WiFi. It details the setup for both iGate and Digipeater modes, including features like transmitting APRS-IS packets over LoRa to local stations and a 30-second buffer in digipeater mode to prevent packet storms. This firmware offers an Ultra Eco Mode, achieving current consumption between **7mA** and **13mA**, making it suitable for remote, battery-powered deployments. The integrated WebUI simplifies configuration and management, providing an accessible interface for hams to deploy and maintain their LoRa APRS infrastructure. It supports sending weather telemetry packets and adheres to APRS protocols, released under the GPL-3.0 license.