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W3HH wide-band wire antenna Article in French. The W3HH antenna, also known as the Terminated Folded Dipole (T2FD), is a compact, broadband antenna for amateur radio. It operates at an angle of 20 to 40 degrees and covers frequencies from 3 to 30 MHz. The antenna features a total length of one-third of the wavelength at its lowest frequency and is fed using a 1:4 BALUN transformer for impedance matching. A termination resistor around 390 Ω optimizes performance, making it suitable for various amateur radio applications while being easy to construct and install.

This is a computer program for Amateur Radio transmission and reception using a computer and radio transceiver The program equips your computer with a one sentence at a time chat-mode for operation on the HF bands. You use it in the same way as you would Skype or cell-phone TXTing. This facilitates rapid-fire QSOs and especially makes nets easier by ZL2AFP

A 7 dB directional gain is reported for this portable VHF Yagi antenna design, which utilizes cut metal tape measure sections for its elements. The resource details the construction process for a 2-meter band antenna, emphasizing its ease of build and portability. It specifically mentions the design's suitability for radio direction finding (RDF), fox hunting, and communication with satellites and the International Space Station (ISS), highlighting its practical applications for amateur radio operators. The construction cost is estimated at under $20, with potential for even lower expense if salvaged materials like old tape measures and PVC pipes are used. The article references _Joe Leggio's_ (WB2HOL) original design, noting specific alterations made by the author. It also compares this design to other DIY Yagi antennas, including _FN64's_ 2-meter band and _manuka's_ 70-cm band tape measure Yagis, underscoring its unique combination of simplicity, portability, and effective performance with a 1:1 SWR achievable on the 2-meter band.

This home made antenna provides around 10.5dBd gain on 70cm, and 6.5dBd gain on 2m, which is more than adequate to work the FM satellites with a handheld dual band radio

Remotely-Operated 1200 Baud AX.25 Narrowband Packet Radio and APRS on a Baofeng UV-5RA and Raspberry Pi 2

SPX Communication Technologies, operating under the TCI International brand, presents a range of radio frequency (RF) solutions primarily for government, defense, and commercial sectors. The offerings include advanced systems for spectrum monitoring, communications intelligence (COMINT), and high-frequency (HF) and medium-frequency (MF) broadcasting and communication antenna systems. Specific product lines encompass _Blackbird_ COMINT systems, _Scout_ spectrum monitoring receivers, and various antenna arrays designed for robust performance in challenging RF environments. The resource details the capabilities of these systems, such as wideband signal detection, direction finding (DF), and signal analysis, crucial for intelligence gathering and regulatory compliance. It also highlights the engineering behind their antenna designs, which are optimized for specific frequency ranges and operational requirements, including high-power broadcast applications and secure military communications. The information presented emphasizes the integration of hardware and software for comprehensive RF situational awareness. The company's focus on empowering partners to "Command the Spectrum" underscores its commitment to delivering critical tools for signal interception, analysis, and management across diverse operational landscapes.

Encouragement for Little Pistols, article originally written for and published in SKIP the monthly newsletter of the Fresno Amateur Radio Club

The SDRanywhere application is an Android app that allows remote operation of an RFSPACE SDR-IQ, NetSDR, SDR-IP or Cloud-IQ radio from anywhere in the world. The demodulated audio and waterfall information is compressed and sent to the client application using a low bandwidth internet connection.

Tables comparing attenuation of common coax cables on amateur radio bands

Adding a full power output 12 meter band capability to the Yaesu FL-2100 despite of 10 meter.

W6CQZ JT65-HF project on sourceforge, the Amateur Radio software for reception/transmission of JT65A protocol with an emphasis upon its usage in the High Frequency Amateur Bands. Project is currently paused.

R3KBO is an amateur radio club producing and developing amateur radio kits and assembled products including HF VHF Power Amplifiers or RF Power Kits and amplifier parts, low pass filfers, band pass filters, sourge protections, splitters and combiners, antenna switches

The Hermes-Lite is a low-cost direct down/up conversion software defined amateur radio HF transceiver based on a broadband modem chip and the Hermes SDR project. It is entirely open source and open hardware, including the tools used for design and fabrication files. Over 300 Hermes-Lite 2.0 units have been successfully built.

Evaluates the **LDG Z100 autotuner**, a device designed to automatically match antenna impedance for optimal transmission efficiency. The review discusses its performance in comparison to the MFJ-902, noting that while the Z100 is a reliable autotuner, it does not match the range of impedances that the MFJ-902 can handle. The Z100 is suitable for operators seeking a 100-watt autotuner that covers HF bands, providing a practical solution for those who require automatic tuning without manual adjustments. The review highlights the Z100's operational context, focusing on its use in HF bands and its practical application in amateur radio setups. While it offers a straightforward tuning process, the Z100's limitations in impedance matching are noted, making it less versatile than some competitors. This comparison provides valuable insights for operators considering an upgrade or replacement for their current autotuner. The Z100's performance is positioned within the broader market of autotuners, offering a clear perspective on its strengths and weaknesses in real-world amateur radio operations.

Cheap but effective multiband quad antenna covering the entire horizon on 10-12-15-17-20m bands.

Demonstrates the complete design and development process for a **Low Noise Microwave Amplifier** (LNA), beginning with conceptual design and progressing through prototyping. The tutorial series covers the initial stages of a single-ended first gain stage, focusing on critical parameters such as noise figure, gain, and stability. It systematically details the theoretical underpinnings and practical considerations for achieving optimal performance in microwave frequency applications. This resource provides a structured approach to LNA construction, enabling radio amateurs and RF engineers to understand the iterative steps involved in realizing high-performance receive-side amplification. It offers insights into component selection, impedance matching networks, and the measurement techniques required to validate design specifications, particularly for **microwave** band operation where noise performance is paramount.

PSK Reporter provides a real-time visualization of amateur radio digital mode reception reports, aggregating data from a global network of monitoring stations. This platform is particularly useful for operators utilizing modes such as FT8, FT4, and PSK, allowing them to observe signal propagation paths and assess their station's reach. The interactive maps display reception reports, enabling hams to analyze band conditions and optimize antenna performance for various frequencies and times of day, aiding in understanding ionospheric conditions. Operators can filter reports by callsign, band, mode, and time, gaining insights into specific propagation events or evaluating the effectiveness of their transmit setup. The data collected helps in predicting optimal operating windows for DX contacts across various digital modes. Philip Gladstone is the contact person for comments and discussions regarding the system.

Some test circuits using the ACE-HF System Simulation & Visualization software, about reciprocal propagation on HF bands by NW7US

Reports indicate the PA1RBZ DX Cluster, previously accessible via telnet at pa1rbz.dyndns.org on port 9000, is no longer operational. The QSL.net hosting platform displays a 404 error, indicating the specific page or file for the cluster's web interface or related information is missing. This service was designed to provide amateur radio operators with real-time DX spotting data, facilitating long-distance contacts across various bands. The cluster's primary function was to aggregate and disseminate DX spots, allowing users to monitor current propagation conditions and identify active stations. Such systems are crucial tools for DXers and contesters, enabling rapid response to new openings and rare DX entities. QSL.net, which hosts over 30,000 amateur radio websites, provides these services free of charge to hams, relying on user donations for operational continuity.

MorseExpert 1.15 decodes Morse Code audio to text, leveraging algorithms from CW Skimmer for optimal performance on weak, fading signals amidst interference on amateur radio bands. It processes audio from the device's built-in microphone or an external radio receiver via cable, optionally highlighting Ham callsigns and keywords. The application features a waterfall display with a bandwidth of 200-1200 Hz, decodes frequencies between 300-1100 Hz, and supports keying speeds from 12-45 WPM with automatic CW pitch detection. Recent updates include support for Android 15, edge-to-edge mode, improved stability, and a pause decoding button. A premium version offers an ad-free experience and user-selected text colors. Users can switch between General Text mode and Ham Radio QSO mode, which enhances word segmentation and highlights callsigns. The app also includes a frequency lock mode, text selection capabilities for copying, sharing, or saving decoded text, and provides guidance on reducing acoustic echo and constructing an audio attenuator for optimal radio interfacing.

The AT-AUTO automatic antenna tuner handles 1.5kW CW operation, employing stepper motors under microprocessor control to precisely position a roller inductor and air-dielectric variable capacitor, avoiding relay-switched discrete components. This design choice prevents loud relay clacking and burning contacts, a common issue with competing products. The tuner features auto-retuning capabilities and receives periodic firmware updates, ensuring continuous improvement and added user-requested features. Its companion product, the _CX-AUTO_ coaxial switch, also features an embedded microprocessor controller. It enables selection of 1-of-8 coaxial outputs via a serial data interface. When integrated with the _AT-AUTO_, the tuner can associate specific coaxial outputs with amateur radio bands, automatically commanding the _CX-AUTO_ to select the correct antenna when the operator QSYs to a different band. Don Kessler began designing the AT-AUTO in 2005, with its debut at the 2006 Dayton Hamvention. Kessler Engineering also offers custom RF product design and electrical engineering consulting, specializing in Class-E RF amplifiers.

The CQ World Wide DX Contest records page details the highest scores achieved in the CQ WW DX Contest across various categories and years. It systematically lists records for both SSB and CW modes, segmenting results by entry class such as Multi-Multi, Multi-Two, Multi-Single High, Multi-Single Low, Single Operator High Power, Single Operator Low Power, Single Operator QRP, Single Operator Assisted High, Single Operator Assisted Low, and Single Operator Assisted QRP. Each record entry specifies the callsign, the operator's callsign in parentheses if different, the year of operation, and the total score achieved. The data is further broken down by individual amateur radio bands, including 160m, 80m, 40m, 20m, 15m, and 10m, allowing for granular analysis of performance within specific frequency segments. The page also includes records for the "ALL" band category, representing cumulative scores across all operational bands. The presented records span from 1948 to 2025, providing a historical perspective on contest performance. This resource also references other CQ contests like CQ WPX, CQ WW RTTY, CQ WPX RTTY, CQ 160, CQ VHF, and WW DIGI, indicating a broader context of contest record keeping. It explicitly states that late logs are not included in the records, ensuring data integrity. The page is maintained by the World Wide Radio Operators Foundation, Inc.

A very popular method of making a short dipoles resonate at a given frequency. This type of antenna is suitable for single band, narrow bandwidth use.

This project details the construction and testing of a M0PLK Delta Loop antenna for the 20-10m ham radio bands. Inspired by positive reviews highlighting its reduced local QRM compared to Cobweb antennas, the author built the antenna using aluminum tubes, DX-Wire FS2 wire, and a 1:4 balun. A mix of custom 3D-printed parts and careful assembly ensured stability and performance. Initial VSWR measurements met expectations, and test QSOs demonstrated success across multiple bands. Future enhancements include adding a lightweight, remote-controlled rotator for directional capabilities.

A home made 4 element yagi antenna that can be easily adapted for 10 meter band

Constructing a dip oscillator provides radio amateurs with a fundamental piece of test equipment for resonant circuit analysis. This particular design, adapted by VK3YE from a concept by _Drew Diamond VK3XU_, details a practical build using readily available components. The unit incorporates four plug-in coils, covering a frequency range from **2.6 MHz to 55 MHz**, mounted on 5-pin DIN plugs for versatility. A salvaged two-gang air dielectric variable capacitor, fitted with a vernier reduction drive, serves as the tuning mechanism, with the smaller gang optimizing bandspread at higher frequencies. In practical application, the dip oscillator is used by setting the meter needle to approximately two-thirds scale. When the instrument's coil is brought near a tuned circuit under test, a noticeable dip in the meter reading indicates resonance. This allows for precise measurement of resonant frequencies in antennas, filters, and other RF circuitry, proving invaluable for homebrewing and troubleshooting. The design emphasizes short wire runs for stable operation, particularly at the higher end of its operational range.

The K9IU Indiana University amateur radio club provides a robust station environment for its members, located within the Indiana Memorial Union. This setup includes a variety of radio resources, making it accessible for students and faculty interested in two-way radio communication, from local ragchews to international DXing. The club's facilities are available for use at any time, fostering an active amateur radio community on campus. Members can engage in various aspects of the hobby, utilizing the club's equipment for operating on different bands and modes. This hands-on access supports learning and practical experience in radio theory and operation, which is crucial for new hams and seasoned operators alike. The K9IU club serves as a central point for amateur radio activities at Indiana University Bloomington, aligning with the university's broader academic and extracurricular offerings.

The Noantri WebCLX presents real-time DX spots, including frequency, DX callsign, country, and comments, facilitating active DXing and contesting. It operates as a web-based cluster, offering an alternative to traditional Telnet clusters for accessing spotting data. The interface displays current UTC, allowing operators to track propagation and activity across various amateur bands. This service is maintained by the _Noantri DX Group ARI Roma_, indicating its origin within the Italian amateur radio community. It supports the dynamic exchange of DX information, crucial for operators seeking new entities or participating in competitive events. Key features include the display of spots for modes like FT8, and it functions as a DXSpider-based system, providing a robust platform for **DX spotting** and **propagation analysis**.

Long distance operations on WiFI band by Yolo Amateur Radio Society

Fundamentals of operating on single sideband

The Kenwood TS-870S HF transceiver features two state-of-the-art 24-bit 20 MIPS DSP chips, providing over 100dB out-of-passband attenuation and CW bandwidth adjustable to 50 Hz. It operates across 160-10 meters with 100 watts output, incorporating digital filtering, a beat canceller, and 100 memory channels. The radio also includes a transmit equalizer, RX antenna input, and a K1 Logic Keyer, enhancing signal processing and operational flexibility for amateur radio operators. Advanced capabilities include IF stage DSP, dual noise reduction, and an auto notch filter, all contributing to superior signal reception and clarity. The TS-870S offers a variable AGC, voice equalizer, and an RS-232C port for computer control, with Windows™ software supplied. Its built-in automatic antenna tuner functions on all bands for both transmit and receive modes, streamlining station setup and operation. Available accessories such as the DRU-3A digital recording unit, SO-2 high stability crystal oscillator, and VS-2 voice synthesizer option further extend the transceiver's utility. The unit requires 13.8 VDC at 20.5 Amps and is supplied with an MC-43S hand microphone, making it a comprehensive station component.

The IZ3MEZ Web DX Cluster presents real-time amateur radio DX spots across 20 distinct frequency bands, spanning from **LF (2190m)** at 135.7 kHz up to **SHF (QO-100)** at 10499 MHz. It displays the DX callsign, frequency, DXCC entity, spotter callsign, and spotter DXCC entity, along with any accompanying comments. The cluster also lists various operating modes such as CW, RTTY, FT8, FT4, FT2, PSK, and SSTV, and supports special operating activities like QRP/P and specific award programs including IOTA, POTA, SOTA, WCA, and JOTA. The cluster's interface provides a dynamic feed of the latest 50 spots, continuously updated with precise timestamps. It offers direct **Telnet protocol** access for users preferring a command-line interface, with configuration instructions provided. The resource also integrates with other spotting networks like RBN and PSK Reporter, enhancing its utility for DXers and contesters seeking propagation information and activity monitoring across a broad spectrum of amateur radio frequencies.

The program consists of tabbed pages for various antenna and transmission line calculation. You can compute the values for an inverted L network that will allow you to match the 50 ohm output of the radio, or you can compute the necessary length in the units of choice for a 5/8 wave vertical for 10 meter band.

The CQ World Wide DX Contest records document top scores, with the Multi-Multi SSB category showing CN8WW achieving **78,170,508 points** in 2000. These records span from 1948 to 2025, categorizing results by region, operating class (e.g., Single Operator High Power, Low Power, QRP, Assisted), and specific bands like 10M, 15M, 20M, 40M, 80M, and 160M. For instance, EF8R (E77DX) holds the All-Band High Power SSB record with **25,747,775 points** in 2025. Each entry includes the callsign (with operator callsign in parentheses for guest ops), year of operation, and total score. The _CQ WW DX Contest_ also features records for the RTTY and VHF contests, alongside the main SSB and CW categories. QRP records demonstrate significant achievements, such as P40W (W2GD) with 5,097,780 points in the All-Band SSB QRP category in 2000. Multi-Two and Multi-Single categories are also detailed, providing a comprehensive overview of competitive performance.

Antenna Authority Inc. offers a wide assortment of directional, wideband antennas and other equipment specifically engineered for radio direction finding (DFing) and geolocation applications. Their product line includes _log periodic_, _cavity-backed spirals_, and _Yagi_ antennas, alongside covert antenna solutions for various operational requirements. The company emphasizes its expertise in designing and manufacturing specialized antennas for both overt and covert operations. Beyond standard offerings, Antenna Authority Inc. provides custom design services to meet specific client needs, focusing on tailored RF directional products. Their capabilities extend to developing antennas for vehicles and optimizing their operational performance in diverse scenarios. The firm is located at 3381 W. County Line Road, Douglasville, Ga. 30135-1145. Ferrel Bentley is associated with Antenna Authority Inc., which has been operating since at least 2005, as indicated by the copyright notice.

On March 27, 2017, the FCC adopted final rules for the USA 630-meter band, detailed in Report and Order FCC 17-33, which required PLC coordination with the Utilities Telecom Council before amateur operations could commence. This resource documents the WD2XSH experimental group's activities, including authorized stations, band plans, and frequency assignments within the 465-515 KHz range, with many stations operating between 495-499 KHz and 501-510 KHz. The site also highlights the WRC-12 decision on February 14, 2012, which granted a new **7-kilohertz-wide** secondary allocation between _472-479 kHz_ for the Amateur Radio Service worldwide. The group's efforts included operating with a maximum ERP of **20 Watts** across 45 stations in the continental USA, Alaska, and Hawaii, using emission modes such as CW, PSK-31, FSK-31, and MSK-31. The site provides links to download FCC 17-33 in PDF and DOCx formats, and offers a station location map, a list of stations by callsign and frequency, and an archive of news updates. Reception reports for any 600-meter station are encouraged to help the amateur radio community understand propagation and repeatability on this challenging band.

J49I operated from Crete Island (EU-015, KM25PH) during the 2008 _CQ WW DX CW Contest_, focusing on multi-operator category participation. The station's activity centered on maximizing contacts and multiplier acquisition across various HF bands during the competitive event. Operators aimed to achieve a high score by leveraging the island's DXCC entity status. The team, comprising Greek and Italian amateur radio operators, utilized the J49I callsign for this specific contest operation. Their efforts contributed to the overall contest results for the 2008 CW segment, with logs submitted reflecting their performance from the European continent.

Fifty-three digital modes, including PSK31, RTTY, and JT65, are explored in this resource, providing detailed descriptions of their underlying technologies and typical use cases. It covers error correction methods like ARQ in PACTOR and FEC in JT65, alongside modulation schemes such as FSK and PSK. The content highlights the evolution of digital communication from traditional TNC-based systems to modern sound card implementations, emphasizing the role of personal computers in advancing these modes. Specific modes like AMTOR, PACTOR, and G-TOR are discussed, noting their baud rates and error correction capabilities. For instance, AMTOR operates at 100 baud, while PACTOR offers 200 baud with Huffman compression. The article also delves into newer modes like MFSK16, which uses 16 tones and continuous Forward Error Correction, and Olivia, capable of decoding signals 10-14 dB below the noise floor. Each mode's bandwidth, speed, and resilience to propagation challenges are examined, such as MT63's 1 KHz bandwidth and 100 WPM rate, or Hellschreiber's 75 Hz bandwidth and 35 WPM text rate. The resource also lists predominant USA HF digital frequencies for bands like 160, 80, and 40 meters, specifying segments for PSK31, RTTY, SSTV, and Packet. It includes links to freeware and shareware sound card software such as Digipan, FLDigi, and MixW, enabling amateurs to experiment with these modes.

This resource documents numerous QRP (low power) portable amateur radio operations conducted by W1PID, Jim Cluett, primarily from various outdoor locations in New Hampshire. The content includes detailed accounts, photographs, and operational specifics for over 350 individual "QRP Adventures," often involving hiking, biking, or kayaking to remote sites. Each entry typically highlights the location, date, bands and modes used (frequently CW on HF), and notable DX contacts made with minimal power, sometimes as low as 200mW WSPR. The site serves as a chronicle of practical QRP field operation, demonstrating successful DXing and contesting from challenging environments. It showcases diverse operating scenarios, from mountaintops like Cannon Mountain and Knox Mountain to lakeshores, riverbanks, and even marine mobile operations. The documented contacts span numerous DXCC entities across Europe, Asia, and the Americas, providing empirical evidence of QRP's efficacy in varied propagation conditions and terrains. Specific events like the Worked All Germany contest, 13 Colonies Event, and CWT sprints are also featured.

Ham radio and cb radio italian only web site dedicated to amateur radio and citizens band

Radioclub KAPA,OM7M Partizanske Slovack republic

This group is for support and discussion of the Baofeng UV-3R micro dual band VHF/UHF radio.

Full article on how to build a home-made wire dipole antenna for 40 and 80 meters band. Article is fully in italian, as it was published on ARI RadioRivista, but is plenty of self explaining pictures that will guide you on homebrewing this trapped dipole antenna for the lower amateur radio bands.

The _Alessandro Volta RTTY Contest_ is an annual digital mode competition focusing on Radioteletype (RTTY) operation, challenging participants to make contacts across various HF bands. This event typically occurs in January, drawing a global field of operators aiming to maximize their QSO count and multiplier accumulation. The contest emphasizes accurate exchange of signal reports and serial numbers, with specific rules governing single operator, multi-operator, and SWL categories. Participants utilize software like _N1MM Logger+_ or _WriteLog_ to manage their logs and generate Cabrillo files for submission. Scoring is based on points per QSO, multiplied by unique DXCC entities and Italian provinces worked on each band. The contest encourages both seasoned RTTY contesters and those new to digital modes to engage in competitive HF activity, promoting skill development in digital communication. Final results and logs are typically published on the contest website, showcasing top performers and providing detailed breakdowns of scores.

Explains the annual Jamboree on the Air (JOTA) event, a global amateur radio gathering for Scouts and Guides. This activity connects young people worldwide through ham radio, fostering international friendship and introducing them to radio communication technology. Participants use various amateur radio bands and modes, including HF, VHF, and digital modes like FT8 and JS8Call, to make contacts with other JOTA stations and learn about the hobby. The ARRL provides resources for Scout leaders and amateur radio operators interested in hosting a JOTA station, including guidelines for setting up temporary stations, safety protocols, and educational materials. The event typically occurs on the third full weekend of October, aligning with the World Organization of the Scout Movement's (WOSM) global schedule. JOTA emphasizes hands-on experience with radio equipment, antenna theory, and basic operating procedures. It serves as a significant public service opportunity for hams to engage with youth and promote the educational aspects of amateur radio.

Near Vertical Incidence Skywave propagation is a form of radio wave propagation used on the MF and HF bands to provide radio communications and broadcasting coverage over short distances, especially where the terrain contains obstacles.

Installing a mobile rig in a vehicle requires careful planning and execution to ensure optimal performance and safety. The process begins with selecting the right equipment, such as the ICOM IC706MKII for low bands and the ALINCO DR-610 for VHF/UHF operations. Proper mounting is crucial; both radios are strategically placed under the back seat of the Silverado, allowing for a clean installation while maintaining passenger comfort. The Hustler antenna, equipped with various resonators, ensures coverage across multiple bands, while the LDG automatic antenna tuner fine-tunes the match for efficient operation. A remote head for the tuner enhances accessibility, making adjustments easier while driving. Each step of the installation is documented to provide insights and tips for fellow operators looking to enhance their mobile setup. The experience shared here reflects practical knowledge gained through hands-on work, aiming to inspire others in the ham community to undertake similar projects.

The 2200-meter band (135.7-137.8 kHz) presents unique challenges for amateur radio operators due to its narrow 2.1 kHz bandwidth, low signal levels, and high noise. W1TAG explores various transmission modes suited for this demanding environment, highlighting that traditional voice modes like SSB and AM are impractical. Plain old CW serves as the baseline, demonstrating effectiveness across different modes, though signal-to-noise ratio (SNR) significantly limits practical speeds. The article notes that reducing CW speed below 5 WPM can improve copy, especially with computer-aided spectrum analysis software capable of decoding signals too weak for human ear reception. QRSS, or "CW sent slowly enough that speeds are best expressed in seconds per dot," is a key mode for LF work, with examples ranging from 3 seconds/dot to extreme 240 seconds/dot transmissions. _Argo_ by I2PHD is mentioned as a simple program for QRSS, enabling reception of signals like BRO, a Part 15 beacon, at a distance of **1100 miles**. Other modes discussed include Dual Frequency CW (DFCW), which uses frequency shifts to distinguish dots and dashes, and Binary Phase Shift Keying (BPSK), a phase modulation technique employing 0 to 180-degree phase flips. WOLF (Weak-signal Operation on Low Frequency), a specialized BPSK form by KK7KA, encodes 15-character messages into 960-bit packages, taking 96 seconds to transmit, and has demonstrated successful reception over **672 seconds** for a message from a 1-watt beacon. Further modes include PSK, FSK variations like JASON and MSK, and graphical modes such as Hellschreiber and Chirped Hell. The article concludes with a practical chart comparing the time required to send a simple message like "WD2XES FN42CH " across these diverse LF modes, offering valuable insights for operators planning contacts on the low bands.

A Quick start guide to NPR New Packet Radio on 70 cm band by the NPR author Guillaume F4HDK. This presentation introducte basic concepts of this niew digital protocol, and guide the user to the first modem configuration both of client and master modems. Includes a final recap of commands.

SDR Project for a compact amateur radio software defined radio trasceiver covering HF bands all mode. Website includes schematics, element PCB, pictures, movies, firmware and elements bom.