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- Software > Aircraft scatter
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- Operating Modes > Aircraft scatter
- Propagation > MUF Indicators
- DX Resources > Beacons > 10 GHz Beacons
- DX Resources > DX Peditions > 2012 DXpeditions
- DX Resources > DX Peditions > 2015 DXpeditions
- DX Resources > DX Peditions > 2018 DXpeditions
- DX Resources > DX Peditions > 2019 DXpeditions
- DX Resources > DX Peditions > 2020 DXpeditions
- DX Resources > DX Peditions > 2021 DXpeditions
- DX Resources > DX Peditions > 2023 DXpeditions
- DX Resources > DX Peditions > 2025 DXpeditions
- Antennas > 6M > 6 meter Yagi Antennas
- Operating Modes > 70 MHz
- Radio Equipment > HF Amplifiers > Acom 1000
- Radio Equipment > HF Amplifiers > Acom 1010
- Radio Scanning > Aeronautical
- Shopping and Services > Aeronautical
- Ham Radio > Clubs > North America > USA > Alabama
- Operating Modes > Internet Linking > AllStarLink
- Radio Equipment > HF Amplifiers > Ameritron AL-811
- Radio Equipment > HF Amplifiers > Ameritron AL-811H
- Radio Equipment > HF Amplifiers > Ameritron ALS-600
- Technical Reference > Amplifiers
- Operating Modes > Satellites > Analog Satellites
- Software > Android
- Antennas > Antenna Books
- Manufacturers > Antenna Masts and Mounts
- Software > Antenna rotor control
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Picture and technical specifications of the Yaesu FT-8800R dual band transceiver
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The Digital Communications Interconnect (DCI) resource details the operational philosophy and technical implementation of an open _MotoTRBO_ IPSC network, emphasizing the use of _c-Bridge_ technology for interconnecting DMR repeaters and talkgroups. It outlines the group's mission to facilitate dynamic connections within the regional DMR amateur radio community by openly sharing network resources and talkgroups, promoting independent network growth and exploring the capabilities of c-Bridge linking. The site provides insights into the technical advantages of c-Bridges, such as breaking the finite peer slot limitation of simple IPSC networks and enabling more flexible talkgroup routing beyond two timeslots. This legacy asset, last updated in October 2022, also reflects on the group's history and challenges encountered in national DMR efforts, citing political divisiveness among major c-Bridge groups. It discusses the practical application of c-Bridges for emergency communications and nets, ensuring redundant talkgroup servers for smooth day-to-day operations and priority events. The resource encourages other c-Bridge operators to adopt international talkgroups like "_iCall Talkgroup_" and a nationwide "Emergency Talkgroup," while also offering guidance on affiliating repeaters or IPSC networks with DCI's open network.
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The Straits Area Amateur Radio Club (SAARC) operates a 146.68 MHz (-) repeater with a PL tone of 110.9, serving Northern Michigan for emergency communications and community support. A temporary cross-band repeater on 445.875 MHz is also available during specific hours, enhancing local coverage. The club actively supports disaster services through its repeater infrastructure and coordinates local community events. SAARC provides resources for prospective hams, including information on licensing classes and testing sessions, and promotes amateur radio education. Members and interested individuals can join the club's Groups.IO group for updates and participate in the Bill DeMay _K8GUG_ Memorial Net, held weekly on Monday evenings at 8:00 PM on the primary repeater frequency.
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Illustrates the fundamental principles of radio repeaters, detailing their role in extending communication range beyond line-of-sight limitations. It begins by defining _simplex communication_ as a direct radio-to-radio link, effective only when no obstructions impede the signal path. The resource then introduces the concept of a repeater (or base station) strategically positioned on elevated terrain, such as a mountain, to overcome geographical barriers. The article clarifies the repeater's operational mechanism: it receives a signal on one frequency and simultaneously re-transmits it on a different frequency, enabling users on opposite sides of an obstruction to communicate. This _duplex operation_ is likened to satellite communication for VHF propagation, but with a fixed terrestrial station. Specific examples of signal paths are provided, showing how a handheld radio transmits up to the repeater, which then relays the message down to another user, effectively bypassing obstacles like hills or large buildings.
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Enables operators to search the XR0ZRC DXpedition log online, a service facilitated by **Club Log**. This tool allows for rapid **QSO verification**, confirming contacts made with the XR0ZRC entity. Users can input their callsign and other contact details to ascertain if their signal report and time match the DXpedition's records, a critical step for award applications like DXCC. The platform offers a straightforward interface for checking log entries, which is particularly useful for those chasing new entities or band slots. It integrates seamlessly with the broader Club Log ecosystem, providing a reliable method for operators worldwide to confirm their DX contacts without requiring a login, reflecting the utility of real-time log updates in the amateur radio community.
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Aircraft scatter is easily seen on the spectrogram window of digital communication apps, when you know what to look for. Examples of real aircraft scatter usage on six meters band
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I have RFI, now what– Locating it. This article is the first of a three parts article, that covers the problem of locating the RFI source. Author make use of an SDR receiver to locate RFI emissions. Ai interesting RFI location process diagrams helps on following the various phases, permitting the discovery of almost 75% of the RFI issues.
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Modifying the Collins KWM-2 for Serious CW Operation, Make this old SSB workhorse perform like it should on CW.
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The Hurricane Watch Net (HWN) is an amateur radio organization dedicated to serving the National Hurricane Center and the public since 1965. It plays a crucial role in disseminating real-time tropical weather information for the Atlantic and Eastern Pacific regions. The HWN operates during hurricane events, providing updates and facilitating communication among amateur radio operators and emergency services. This network is essential for ensuring that communities are informed and prepared for severe weather conditions. In addition to its operational role, the HWN offers educational resources and outreach programs aimed at enhancing public awareness about hurricane preparedness. This includes providing access to tracking maps, storm surge information, and safety guidelines. The HWN encourages amateur radio operators to participate in its activities, fostering a spirit of community and collaboration in the face of natural disasters. By subscribing to their email updates, individuals can stay informed about active storms and receive vital safety information.
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The Dickson County Amateur Radio Club (DCARC) operates as a local organization for amateur radio enthusiasts in Middle Tennessee, providing a focal point for hams in the area. The club's activities typically encompass local nets, technical discussions, and support for emergency communications, aligning with the public service aspects of amateur radio. Members often engage in various operating modes and bands, sharing knowledge and experience to enhance their collective skills. Club members participate in field days, local contests, and community events, demonstrating the practical applications of amateur radio. These gatherings offer opportunities for new hams to gain practical experience and for seasoned operators to mentor others, strengthening the local amateur radio community. The DCARC serves as a hub for camaraderie and mutual support among its members, contributing to the vibrant ham radio scene in Tennessee.
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Online HF Communication prediction system provided by the Australian Governament Buerau of Metereology allow to predict usable frequency rage for radiocommunications between two stations allowing to specify frequency and date range. This tool allow calculation with different methods and algorithms
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Results or performance test using an harpin antenna for the 7 MHz
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This page provides a fully customizable band plan. You can easily customize the frequency limits, scale, define custom windows for modes and activities, adding or removing bands. You can tehn Export to PDF or print the bandplan to distribute the document to help hams operating within the designated spectrum efficiently. Useful for both new and experienced hams looking to produce their custom bandplan.
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Over 100 FCC districts are analyzed by this resource, providing a predictive database for amateur radio vanity callsign assignments. The system simulates the FCC's application process, calculating the probability of assignment for specific callsigns, such as KD3Q at 94% or N9QC at 97.8%. Data is meticulously organized by FCC district, detailing available, pending, and upcoming callsigns, alongside those currently blocked by renewal or other FCC administrative actions. This allows hams to gauge their chances of securing a desired callsign. The database presents specific application entries, including the date entered, receipt date, process date, the applicant's current callsign, and the vanity callsigns they have applied for. Each entry facilitates examination of predicted outcomes, which categorize potential assignments as assigned, competitive, non-assigned, unneeded, curable, or unknown status. For instance, an application for K7DM clearly shows multiple applicants, indicating a highly competitive assignment scenario. This tool is particularly useful for those seeking a **short callsign** or a **1x2, 2x1, 2x2, 1x3, 2x3, 3x1, 3x2, or 3x3 callsign** that aligns with personal preferences or contest aspirations. It provides a clear, data-driven perspective on the likelihood of obtaining a specific vanity callsign.
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Alpha 87A Amplifier Fault 1 and the downlevel amplifier
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These frequencies have been adopted into the bandplans of each IARU region to be a focus for emergency communications in their areas. They are not absolute frequencies but instead are centres of activity and emergency communications may be found around 20kHz from these centres. Some countries may maintain other emergency frequencies in their own bandplans due to local requirements, QRM etc
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Procedure for foreign ham radio licensees to establish a station in Japan
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Reflected power and VSWR Metering on Yaesu FT-817, and proper interpretation of real values. The power output meter it is a relative indicator of the antenna match that the radio is experiencing. Reference table and how correctly read the values of the Yaesu internal meter.
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The weather station described here uses a TTGO v3 1.6.2 module and various sensors. It displays the data on an OLED screen and transmits them among a choice of protocols to the APRS, APRS-IS, Wunderground servers or via an MQTT broker. APRS data is transmitted on 433.775 MHz (can be changed) using the LoRa protocol. APRS beacons picked up by iGate gateways are then transmitted to APRS servers.
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Showing aircraft scatter reception in action.
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Presents two distinct hardware modifications for the Icom IC-7300 transceiver, detailing the necessary steps for each. The first modification, a _MARS_ transmit expansion, involves the physical removal of specific surface-mount diodes (D422) from the main board, enabling transmit capabilities across a broader frequency range, including out-of-band frequencies. It specifies the diode location on US versions of the IC-7300 and suggests using small diagonal cutters if a soldering iron is not preferred or available. The second modification focuses on the internal antenna tuner, aiming to provide wider impedance matching capabilities. This involves adding a **100k ohm** resistor to a designated point within the tuner circuit. The resource also briefly mentions a microphone modification for the _HM219_ and a general power increase, though without specific instructions for the latter two. It emphasizes safety precautions, such as disconnecting power and inspecting the work area.
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QSO Procedure for Airplane Reflections, Reporting system and procedure, confirmation procedure and requirements for a complete QSO
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Aircraft can also be used to increase communications range, by using Aircraft Scatter
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Presents an interactive **Ham Bands Explorer** web application, offering a live view of all amateur radio bands overlaid on a world map. This resource displays **CQ zones** and **ITU zones**, with geographical data sourced from HB9HIL/hamradio-zones-geojson under an MIT license. The interface provides a dynamic visualization of global band conditions, enabling operators to observe activity patterns across different regions. Users can select individual countries to retrieve and display their specific band plans, with frequency coverage details loaded from CountryData.json. The tool indicates 100% frequency coverage, ensuring comprehensive data presentation for selected regions. This functionality supports detailed analysis of national regulatory variations within the amateur spectrum. The application integrates both a map view and a live view, facilitating real-time monitoring and geographical context for band usage. It serves as a practical reference for understanding international amateur radio regulations and visualizing propagation characteristics across various frequency allocations.
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You can use this tool to calculate the maidenhead square by entering the longitude and latitude.
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The Shiawassee Amateur Radio Association (SARA), operating under the call sign W8QQQ, serves as a non-profit amateur radio organization in lower central Michigan's Shiawassee County. Its primary objectives include public service, emergency communications, and advancing amateur radio through education and technical excellence. The club maintains a weekly _Skywarn_ 2m net on the N8VDH repeater at 147.02 MHz (+.6 MHz, 100 Hz tone) every Monday at 7:00 PM, actively seeking more local hams to participate. SARA also facilitates VE testing, with upcoming sessions like the one scheduled for April 23, 2026, at 6:30 P.M., requiring pre-registration by April 20. SARA holds monthly meetings at the James P. Capitan Building in Corunna, typically on the second Tuesday of each month at 7:00 PM local time, excluding December's social event. They offer Zoom meeting options for members unable to attend in person. Annual dues are $15.00, with a reduced rate for new licensees, making it a very low-cost club. The organization actively seeks more EMCOMM assistance from all Shiawassee County hams, not just club members, to bolster their ARPSC (ARES/RACES) capabilities, noting that only about **10** out of **200+** county hams are currently active in ARES. They also maintain a Google Group, "W8QQQ," for electronic notifications and club communications.
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The U01 emergency communications antenna is a versatile, multiband antenna designed for 80/60/40/20/17/15/10m bands, known for its reliability and compact size. It features a broadband transformer wound on various core options like FT82-43, FT114-43, or FT140-43, with the latter capable of handling up to 100W. The antenna incorporates a PCB with options for SMA and BNC connectors, and a weather-proofed design for durability. The lightweight construction, using materials like DX Wire UL and Polyester rope, makes it highly portable. The antenna's design has been tested and proven within the DARC Chapter U01, with multiple build options and detailed documentation available for DIY enthusiasts.
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ICOM IC756 PRO II III, PS125 Fan Modifications, install an external cooling fan on the ICOM IC756 PROIII to minimize the heat on the chassis, then will perform a fan modification on the ICOM PS125 power supply to minimize the fan noise.
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IOTA DXpedition will happen from 9th till 18th of April 2018 OC-265
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The mini Radio Solutions miniVNA PRO is the only affordable vector network analyser (VNA) I know of that offers remote wireless operation. This is very interesting because it allows to measure the input impedance of HF antennas installed at height without having to deal with coax cable lengths, baluns nor common mode suppression chokes. However, to render the miniVNA PRO truly field proof, it requires a number of significant modifications.
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Since 1988, Royal Communications International has been supplying communications equipment designed for the military, professional, and amateur market. We specialize in the sale and service of High Frequency, Single Sideband transceivers that are dependable and easy to use.
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How to install INRAD filters on the FT 847
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This interface includes both the CAT and the PTT circuits,and it can be controlled from a single COM port for the Yaesu FT-817 transceiver
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CW Morse Nano QRP and Micro Keys. CW Morse PCB Keys. Morse Keyers
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This page contains draft of USB CAT interface for Yaesu 8x7 (817, 847, 897). Tested with FT857 by OK1USW.
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Homemade custom CAT interface cable for the Yaesu FT-817 this article include schematics diagram for the interface and some pictures
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Serial CAT interface to control a Yaesu FT-817 transceiver. Inspired in the James Buck (VE3BUX) FT-857D library and crafted to Andy Webster FT-817_Buddy project, but usable by anyone to control a FT-817 radio.
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Collection of modifications for the Retevis RT3, a monoband handheld transceiver for DMR (digital voice) and analog FM. It is almost identical to the Tytera MD-380.
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In this post, we describe how to make a pigtail cable to connect the Kenwood TH-F6A triband HT to a 12Vdc power source via an Anderson PowerPole connector.
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Open source code to add CQ Zone, ITU Zone and Maidenhead Locator to your leaflet maps.
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The article enlightens radio amateurs on utilizing real-time space weather data to optimize HF communication. Navigating through Hp30 index, MUF, f0F2, and eSFI metrics, it explains their significance in band selection and propagation forecasting. With essential links and practical insights, enthusiasts learn to discern optimal conditions for high-band DX, low-band DX, and NVIS operations. The author's observations and antenna optimization tips enrich understanding for effective HF operations.
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N6CTA provides a comprehensive tutorial on manually configuring NTP synchronization for Debian Linux, ensuring accurate system time for FT8 and other amateur radio modes. The guide covers updating the system, installing and enabling NTP, verifying the timezone, and using the iputils-clockdiff tool for precise time comparison. A script is included to check and sync system time, enhancing the performance of synchronous modes like FT8.
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The *SPACE* Amateur Radio over Internet Protocol (RoIP) system offers public audio transmissions from NASA Mission Control and astronauts, primarily for educational purposes. This service streams NASA public media sources, including *Artemis II* and the ISS public audio channel 2 feed, which predominantly features English communications. Astronaut activities on the ISS typically occur between 0700 UTC and 19:00 UTC, with transmissions most common during early mornings USA time, alongside special events such as launches or spacewalks. Users can connect to the live stream via EchoLink to the *SPACE* conference, via IRLP to the 0100 experimental reflector, or via Allstar to node 516221. EchoLink connections utilize the GSM CODEC, while IRLP and other connections default to uncompressed or u-law CODEC. The service notes that long periods of silence are common, and NASA audio sources can be periodically unavailable or noisy. Daily recordings of these transmissions are published at space.rfnet.link/recordings/, available as .ogg audio files for direct playback or .m3u8 playlist files for network streaming in applications like VLC. Each playlist file provides a list of timestamped audio transmissions, allowing users to review specific segments of interest.
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GridViewer is an interactive and lightweight open source web-based tool designed for ham radio operators to visualize and analyze their worked grid squares from ADIF-log files. GridViewer was developed to address a real-world challenge faced by many ham radio operators using lightweight or single-board computers like the Rock 4 SE (in my case) or Raspberry Pi.
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Ferrite E-cores offer a practical solution for constructing baluns, especially when connectors are already mounted on cables. These cores, commonly used in mass-produced pulse transformers, allow for multiple turns without dismounting connectors, making them ideal for control and power supply cables. The material of E-cores is generally suitable for common mode baluns up to 15 MHz, providing a cost-effective option for amateur radio operators. E-cores can often be sourced from old switch-mode power supplies, adding to their appeal for those looking to utilize existing resources. A notable example involves a balun on a USB cable using a Ferroxcube E 32x16x9, 3F3 core with four turns, secured by three cable ties. This setup demonstrates the ease of construction and stability achievable with E-cores. Another example features a balun with eight turns of shielded cable with RCA connectors on the same core, achieving 140 uH inductance at low frequencies. The impedance plot for this configuration is measured between the shield ends, illustrating the effectiveness of E-cores in practical applications. The article includes detailed figures and descriptions, providing valuable insights into the construction and application of baluns using ferrite E-cores. These examples serve as a guide for amateur radio enthusiasts looking to enhance their setups with cost-effective and efficient solutions.
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The **qrh-OS** application functions as a dedicated ham radio operating environment within Windows 10 and 11 systems, providing a consolidated platform for various amateur radio activities. It does not alter core system settings but instead presents a virtual desktop populated with specialized utilities and an integrated CAT radio system. This design aims to streamline the operator's workflow by centralizing tools often used for DXing, contesting, and general operating. Key features include a Telnet terminal for DX Cluster connections, real-time APRS tracking, and **CAT control** for transceivers, enabling one-click tuning from various integrated modules like Cluster, POTA, SOTA, WWFF, and Visual DX. The software also incorporates a worldwide Amateur Radio contest calendar, tools for Flora & Fauna activations, and displays for HF Low Bands Beacons and HF propagation conditions. Further utilities encompass a MeshCom Map, POTA Tunable, Reverse Beacons for WSPR network monitoring, SOTA Tunable, and a Timezone display. Visual DX offers an interactive globe showing DX stations and frequencies, while WebSDR/KiwiSDR access extends listening capabilities. An integrated IPTV player and real-time weather maps round out the comprehensive suite, all accessible within a single-window interface.
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Antennas for low-power operation resemble those for 100W use. Minor adjustments, like capacitor voltage ratings, may apply, but basic principles persist. Portable antennas, notably Backpack Antennas for weight-conscious setups, hold relevance beyond QRP. While some antennas function acceptably at higher power, efficiency issues arise at QRP levels. Testing antennas at 100W exposes weaknesses, particularly in tuners, crucial for efficient QRP operation.