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Book on CW paddles, history of keyers, keyboards, oscillators, and all things related to automatic Morse code.
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This is a small collection of K9YC info and my experiences. Problems by feed lines of 1/2 lambda length. CMCs in transmitting and receiving systems. Antenna unbalance, Maximal allowed power, Choke winding tips.
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This article provides details on building a 6 Meter J-Pole antenna using PVC pipe for an enclosure.
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QSO Recorder Indexing service. This site allows radio amateurs to share their contest and DXpedition audio recordings, usually made with the N1MM Logger+ and the Qsorder plugin
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Spy Numbers Stations are shortwave radio stations that are speculated to have been broadcasting since World War I. The true origin and purpose of them are unknown. A popular theory is that these stations are intended for spies in the field using a One Time Pad. Another theory is that they are used in drug smuggling operations.
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The program serves to assist in a ham-radio activities secretarial with his hobby , such as Printing QSL cards or print labels directly from the program , printing envelopes and mailing envelopes for the feedback you send direct QSL cards, download address for sending cards direct from QRZ.COM or for any station. Checking whether for the QSO and his country is present QSL bureau.
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This stacking offers a well known simple phasing technique. All elements can be fed in parallel by open wires provided that they are fed in phase. This can be achieved by twisting the open wire phasing-lines at 180 degrees.
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Risca and District Amateur Radio Society Tredegar Terrace Risca Nr Newport
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Mounting on roof at the right ground level can greately impact on antenna performances because will affect the radiated angle of energy.
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This is a simple 2.4 GHz SWR meter which is based around surplus microwave hardware which can be easily found. The main component is a MECA -20/-20 dB Directional Coupler which has a frequency range of approximately 700 MHz to 2.5 GHz.
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Modification to an old cellular phone base station modules, with a fairly reduced output power (10 watts or so), the stock power amplifier modules will cover the 2.3 GHz and 2.4 GHz amateur radio bands.
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Undertanding the velocity factor in coax cable feed lines. Meaning of the veolcity factor index related to the RF speed of a signal inside the coax cable.
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A unique, easy-to-use Amateur Radio program for creating County, State, Section and Grid Locator outline maps of North America that can be filled by Hand, from a Contest Logger UDP Feed, or from Imported ADIF or Cabrillo Logs.
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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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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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PI-RX is a beacon monitoring program capable of decoding PI4 and showing the performance of the decoded signal
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DL7AFS, Babs and DJ7ZG 5-19 November 2012
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KlaTrack is a Windows-based software application designed to assist amateur radio operators with satellite communication by predicting spacecraft visibility. It provides a simple interface to determine when specific satellites will be above the local horizon, a critical factor for successful two-way contacts via amateur radio satellites. The program processes _Two-Line Element_ (TLE) data to calculate orbital mechanics, offering a practical tool for satellite operators to plan their operating windows. It supports real-time tracking and displays essential pass information. This utility simplifies the complex task of satellite tracking, allowing operators to focus on making contacts rather than manual orbital calculations. While specific gain figures or distances are not quantified, the software's core function directly supports achieving successful satellite QSOs by providing precise pass predictions. It is particularly useful for operators engaging in activities like working the International Space Station (ISS) or other low-Earth orbit (LEO) satellites, where short pass times and precise timing are crucial for maximizing contact opportunities.
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On this page, you will find one of my designs; An Audio Selection Panel (ASP). The Audio Selection Panel allows you to control 4 Transceivers and hear the audio through the built-in loudspeaker and on an external boomset (combination Microphone/ headset). On or more transceivers can be selected at a time to transmit and/ or receiv
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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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A comprehensive morse code auduio guide with several youtube movies classified by skill level, characters and numbers, sentences, speed level and more. All movies are linked by an interactive interface that let you select the speed and the excercise type. The page contains an downloadable set of morse code exercises and several other resources
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Free PDF book to start learning morse code and to improve your proficiency, freely available in four languages english, german french and italian.
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Data Decoder Utility is designed to enhance the operating experience for Flex Radio users by providing advanced connectivity to Peripheral equipment and radio control programs (RCPs) otherwise not available.
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When building antennas for the Wifi band (Like the 8dBi omni), a need for an easy way to check the antennas arose. A Voltage Standing Wave Ratio (VSWR) meter useable at the 2.4GHz band is however, hard to find.
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A CW contest running every Monday, from 1630 UTC to 1729 UTC on 40 and 80 meters band
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TN5R will be active from March 9th to March 19th, from 10 to 160 meter on CW, SSB and RTTY
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The article describes the construction of a 1:49 impedance transformer designed to match the high impedance (around 2500Ω) of an end-fed half-wave (EFHW) dipole antenna to the 50Ω impedance of a typical transceiver. The EFHW is a popular portable antenna due to its simple construction, but feeding it can be challenging compared to a center-fed dipole. The transformer was built using an FT240-43 ferrite toroid core, with 2 primary and 14 secondary windings for a 1:49 impedance ratio. A capacitor was added in series with the primary winding to improve performance at higher frequencies. The author compared versions with one and two cores, and found that 100pF worked best for the single core design while 200pF was optimal for the dual core transformer.
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A QSL Cards collection divided into North American Shortwave Pirate Radio QSLs abd European Shortwave Pirate Radio QSLs
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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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Aurora forecast is updated daily at midnight UTC includes Kp Index forecast for next 3 days
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Professional SDR Signal Analysis Tools - Khanfar Spectrum Analyzer offers specialized SDR software tools for signal analysis, including real-time FFT analysis and precise frequency selection. The website provides a range of software for signal monitoring, spectrum analysis, radio direction finding, and antenna systems.
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The 222 MHz Transverter project, based on Zack Lau's (W1VT) original July 1993 QEX magazine design, provides an IF of 28 MHz for both transmit and receive paths. Rick Bandla (VE3CVG) contributed supplemental notes and construction details, including modifications to achieve 10 mW output power from an initial 4 mW PEP. The design incorporates three distinct boards: a Local Oscillator (LO), a Transmitter (Tx), and a Receiver (Rx), with an estimated parts cost of just over $150 CDN, significantly less than commercial kits. Construction involves both through-hole and surface-mount components, with specific guidance on mounting MAV and MAR devices, grounding techniques, and component selection. The project details include parts lists, schematics for the LO, Tx, and Rx, and board layouts. Troubleshooting advice emphasizes sequential testing, starting with the LO, then Tx, and finally Rx, using a 194 MHz and 222.100 MHz capable FM handheld for signal tracing. Further enhancements are discussed, such as an optional Tx driver stage to boost output to 100 mW and the potential modification of a Motorola Maxor 80 PA for 222 MHz SSB/CW operation. The resource also covers practical aspects like power attenuation pads for IF radios (e.g., FT817) and considerations for enclosure design, including repurposing a Maxor 80 case. Performance reports indicate successful 70 km contacts with only 4 mW output.
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SkyRoof is an open-source, 64-bit Windows application designed for amateur radio operators and satellite enthusiasts, combining satellite tracking and Software Defined Radio (SDR) functionality in a unified platform. The software provides real-time satellite tracking, pass predictions, and visual representations through Sky View, Earth View, and Timeline displays. It features an SDR-based waterfall display covering VHF/UHF satellite segments with Doppler-corrected frequency scales, automatic satellite labeling, and visual tuning capabilities. SkyRoof supports various SDR devices (Airspy Mini, SDRplay, RTL-SDR), external transceiver CAT control, and antenna rotator integration. The application automatically downloads satellite data from SatNOGS and other sources, offers voice announcements for satellite passes, and includes comprehensive frequency control with Doppler tracking, manual corrections, and RIT functionality for enhanced satellite communication operations.
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This is a power amplifier project for a RF 600W 1.8 MHz to 70 MHz linear amplifier including a Low Pass Filter. Projects includes schematics, pictures, PCD design, fans details, note on PA ferrite chokes and assembling instructions
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The quarter-wave Marconi working against ground is a popular and inexpensive antenna for 160 meters. A lot of newcomers to the band favor this simple antenna because it's easy to put up, it isn't too big, and it works.
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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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SWR Magazine is free montlhy ham radio online magazine published in English and Spanish. SWR Magazine presents a mix of analysis, hands-on experience, and technical insight for ham radio operators. Covering global radio trends, technical topics like antenna takeoff angle, operating practices outside the shack, reviews of radios, propagation. Explore innovative antennas, digital modes like RTTY, and historical radio origins. This issue bridges the past, present, and future of amateur radio, inviting readers to not just read, but experience and experiment with the content.
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An easy to build 6 watts SSB transceiver for 14MHz. BITX is an easily assembled transceiver for the beginner with very clean performance. Using ordinary electronic components and improvising where specific components like toroids are not available, It has a minimum number of coils to be wound.
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The yearly, black, up to 1750, and monthly red, from 1750 up to now, sunspot numbers provided by the Royal Observatory of Belgium SILSO
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The page presents JRX, a virtual radio receiver interface written in Java that can connect to about 200 ham radio transceivers and receivers using the Hamlib library. It offers features like 200 read/write memories, a programmable scanner, and spectrum scope, making it easier to use than traditional radios. The article explains the benefits of virtualizing a radio with controls and highlights the advantages of using JRX, especially for radios requiring computer control. Author P. Lutus provides insights on the development of JRX and its improvements over previous virtual radio projects.
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HFN (Hands Free Nanokeyer) is a 3D Printer made morse keyer. In this project the athor shares the STL printer model files for the 3 versions build.
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Getting started with LoRA a documented experience with LoRA Gateway, Antennas and simple application
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This article explores the revival of the classic 3 Transistor Short Wave Radio kit originally offered by Radio Shack in the late 1960s. Updated with modern silicon transistors and components, the design retains its educational charm while enhancing performance. Detailed assembly instructions and illustrations are provided to facilitate replication. The project not only pays homage to nostalgic electronics but also serves as a practical introduction to radio theory, including modulation techniques and receiver types, fostering a hands-on learning experience for enthusiasts.
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World Radiosport Team Championship, Germany July 12-16 2018
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A home made project for a 7 element yagi antenna for the two meters band based on the DK7ZB original desing.