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The HotPaw Morse Code Decoder application for macOS processes audio input to transcribe Morse code characters into text. It presents both an audio spectrum graph and a tone amplitude graph, which aid in configuring a narrow band audio filter. Operators can set the audio filter for tone frequencies between 400 and 1600 Hz, optimizing reception for various CW signals. The software offers user-configurable settings, including WPM dot/dash speed detection, a noise threshold level, and the option to use Farnsworth timing for inter-character spacing. The Morse code WPM detection automatically adapts from approximately 8 to 40 WPM, with a lock feature for the estimated speed. A High Speed WPM Mode is available for code speeds ranging from 40 to 80 WPM, catering to faster CW operators. The application's decoding performance is influenced by signal level, signal-to-noise ratio, frequency and WPM stability, keying quality, and proper configuration, with an initial learning phase required for WPM estimation to stabilize. An external microphone or line-in may be necessary for optimal performance on some MacBook models to mitigate fan noise or room reverberations. Version 1.4.4, updated on November 11, 2021, includes compatibility improvements for newer macOS releases. The developer, Ronald Nicholson of HotPaw Productions, does not collect any user data from the application.

Presents a comprehensive listing of VHF and UHF repeater systems operating within Ecuador, detailing their operational frequencies and geographical coverage. The resource includes specific entries for locations such as _Guayaquil_, Cuenca, and Manta, alongside their respective frequency pairs. For instance, the Cerro Azul repeater in Guayaquil operates on **6.760- T**, indicating a transmit offset, while the Sta. Elena system utilizes a 26.660 MHz transmit frequency. The data provides essential information for local and visiting amateur radio operators seeking to utilize regional repeater infrastructure. It delineates coverage areas using two-letter provincial abbreviations, such as AZ for Azuay and GY for Guayas, facilitating route planning and mobile operation. This compilation is particularly useful for those engaged in local communications or emergency preparedness within the Ecuadorian amateur radio community, offering a practical guide to available repeater assets.

Presents a detailed compilation of **6-meter** voice repeaters operating within the 53-54 MHz segment across Australia (VK) and New Zealand (ZL), providing essential data for local and visiting radio amateurs. Each entry specifies the repeater's output and input frequencies, its assigned callsign (where applicable), the primary service area, current operational status (e.g., operational, under construction, scrapped), and a **Maidenhead grid locator**. The resource also includes the date the repeater was last heard or updated, offering insights into its recent activity. This listing is meticulously maintained by VK2KFJ, who updates entries based on personal observations and confirmed reports from other operators. It serves as a practical reference for hams seeking to utilize the 6-meter band for local communication via repeaters, particularly for those engaged in mobile or portable operations within the specified regions. The data helps operators configure their transceivers correctly for accessing these vital communication hubs. Beyond the repeater details, the page also notes common 6-meter FM voice simplex frequencies, such as the 52.525 MHz international call frequency, and lists historical packet simplex frequencies, though their current operational status is uncertain. This comprehensive approach ensures that operators have a broad overview of 6-meter activity in VK and ZL.

Over 100 amateur radio beacon audio files are presented, offering a direct auditory experience of propagation conditions across a wide spectrum of frequencies, from 1.8 MHz to 47 GHz. These recordings, primarily captured by IW3FZQ and IK3NWX, document signals from beacons such as DK0WCY, IY4M, GB3RAL, and S55ZRS, providing a valuable resource for **propagation study** and **beacon monitoring**. Each entry in the list specifies the beacon's callsign, its operating frequency in kHz, and the recording operator. This compilation includes signals from beacons located in various grid squares like JN55VF, JO44VQ, and IO91IN, illustrating diverse geographical origins. The frequencies covered span the 160m, 80m, 40m, 30m, 20m, 17m, 15m, 12m, 10m, 6m, 4m, 2m, 70cm, 23cm, 6cm, 3cm, 1.2cm, and 6mm amateur bands. Users can listen to these recordings to identify characteristic beacon tones and observe signal strength variations. The resource also invites other radio amateurs to contribute their own beacon audio files, fostering a collaborative archive of propagation data. The last update to this collection was on March 24, 2009, indicating a historical snapshot of beacon activity. Accessing the files requires the Real Player software.

Shortwave listeners and amateur radio operators interested in _numbers stations_ can engage with this mailing list, which serves as a platform for discussing the enigmatic transmissions. The resource facilitates the exchange of information regarding these unusual broadcasts, often associated with intelligence agencies, by allowing members to share observations, decode attempts, and theories. It provides a community space for those who monitor the HF spectrum for these unique, often automated, voice or digital signals. Participation on the list enables members to contribute to a collective understanding of numbers station activity, including changes in frequencies, broadcast schedules, and message formats. While specific technical analysis or signal processing techniques are discussed by members, the primary function is information sharing. The list is administered by csmolinski at blackcatsystems.com, and prior postings are archived for reference, allowing new members to review historical discussions and data.

Digital Smart antenna (DiSA) Automatically Adjusts over a wide band of frequencies.

Pages fully dedicated to beginners guides, includes an interesting sample of a CW QSO, and a list of frequencies to practise morse code, useful for beginners,

The following table is adapted from the International Telecommunications Union Radio Regulations Appendix 18, including changes adopted by the 2012 World Radio Conference.

This resource provides a detailed historical record of satellite downlink frequencies, systematically organized by both frequency range and the satellite's launch year. It presents extensive listings covering segments from 8 MHz to 9000 MHz, including specific breakdowns like 136-137 MHz and 1600-2200 MHz. The data is segmented into distinct frequency blocks, offering granular information for various bands. The content delineates frequencies for satellites launched across several decades, with specific sections for years such as 2004, 1999, and extending back to 1967. This chronological organization allows for tracking the evolution of satellite communication frequencies over time. The resource serves as a reference for identifying operational downlink frequencies of historical space assets, which is particularly useful for satellite enthusiasts and those interested in _space tracking_ or _vintage satellite_ communications. The utility of this compilation lies in its specific historical data, providing a unique perspective on past satellite operations and frequency allocations.

With the view to establish a quick and easy multi-band antenna deployment for portable and camping operations a simple long wire antenna with an earth or earth plus counterpoise arrangement with a 9:1 voltage unun including a tuner or simply with a tuner is one possible solution. With the 9:1 voltage unun and wire lengths suggested in the below tables the antenna should present non extreme impedances for all HF amateur band frequencies. This page is far from complete and represents the ongoing investigation into this type of antenna. Experiments to date seem to have raised more questions than obvious answers.

Accurate calibration of your receiver and sound card is necessary for good results with the weak signal modes in use at LF. Modern receivers with master oscillators that are synthesized to provide all conversion frequencies greatly simplify the process. This article describes a method of making the necessary measurements and adjustments to an ICOM R75 receiver and a sound card, using the ARGO software

Iphone App with list of nearby repeaters in the UK, along with details of input and output frequencies, a map, and a handy bearing arrow for each repeater.

Shelby amateur radio club's VHF emergency net is open to all within the repeater's coverage area. 146.880 and 147.345 are the repeater frequencies. Shelby Radio Club is the sponsor of the Shelby hamfest.

Accurate frequency measurement is crucial for amateur radio operators, particularly when building or troubleshooting transceivers and test equipment. This resource details the construction of a _PIC microcontroller_-based frequency counter, providing a practical solution for precise frequency display. The design incorporates an LCD readout, offering clear visual feedback of measured frequencies. The counter can operate as a standalone unit, useful for general bench testing, or be integrated directly into a receiver. Its built-in offset functionality allows for seamless integration, enabling the display of the received signal frequency rather than the intermediate frequency. The project focuses on accessible components and construction techniques, making it suitable for homebrew enthusiasts. Key features include a measurement range up to **50 MHz** and a compact form factor.

Presents the Amateur Radio on the International Space Station (ARISS) program, a global educational initiative facilitating direct communication between students and astronauts via amateur radio. It outlines the operational framework for scheduled school contacts, detailing the technical requirements for ground stations and the typical Q&A format used during these events. The program utilizes VHF/UHF frequencies for voice and packet radio communications, enabling students to engage with crew members aboard the ISS. ARISS supports various educational objectives, promoting STEM fields through hands-on radio experience. The resource provides information on how schools can apply for contacts, the selection process, and preparation guidelines. It also covers the history of amateur radio in space, including past missions and the evolution of equipment used on the ISS. Regular updates on contact opportunities, operational status, and technical specifications for ARISS hardware are provided.

In the VLF portion of the spectrum it is easy to listen to the emissions created by the Earth itself. These emissions are generated by many different mechanisms and are often beautiful to listen to. Coverage on LF and MF frequencies

Tri-Cities Frequencies, Live Scanners, CTCSS information and more

Nice feature of the Baofeng UV5R family is that they support 6.25kHz tuning steps. That fact makes it possible to dial in the radio to use the exact PMR446 channel frequencies rather than a nearest fit which is the case in many other transceivers.

The HA8TKS VHF DXCluster is an essential online resource for amateur radio operators focusing on VHF and higher frequencies. This platform provides real-time information on DX spots, allowing users to track and engage in two-way radio communications effectively. The integrated map mash-up feature enhances the user experience by visually displaying the locations of DX stations, making it easier for operators to plan their contacts and optimize their antenna setups based on geographical data. In addition to the DXCluster functionality, the site offers various HAM tools, including a QRB calculator, which helps operators determine the distance to DX stations based on Maidenhead grid locators. The platform supports multiple modes of operation, including CW, SSB, RTTY, and digital modes like FT8 and JT65. With a user-friendly interface and comprehensive data, the HA8TKS VHF DXCluster is a valuable asset for both novice and experienced operators looking to enhance their DXing and contesting activities.

Manually programming D-Star handheld transceivers like the _Icom ID-51A_ and _ID-31A_ can be a straightforward process, enabling operators to configure repeaters, simplex frequencies, and D-Star specific settings without relying on computer software. This method is particularly useful for field operations or when quick adjustments are needed, allowing hams to set up callsign routing, DR mode, and reflector links directly from the radio's interface. Understanding the menu structure and key sequences is crucial for efficient on-the-fly programming. Operators often find manual programming invaluable for activating new D-Star repeaters encountered during travel or for participating in local nets where specific G2 or G3 gateway configurations are required. While software like _CS-51_ offers convenience for bulk programming, the ability to manually input frequencies and D-Star parameters ensures operational flexibility. This approach also helps hams troubleshoot connectivity issues by verifying individual settings directly on the transceiver, ensuring proper D-Star registration and gateway access.

QRP Popular Frequencies, where to operate in QRP mode

List compiled by N4LCD with description of main frequency usage

This is about Small Antenna types and their properties which can help choosing proper antenna for high-frequency wireless communications as: two-way radio, microwave short links, repeaters, radio beacons or wireless telemetry

Manufacturer of WiFi (2.4 & 5 GHz), Marine WiFi, Military and other antennas of various frequencies and styles.

Frequencies and location of every meteo radiosonde launching centres in Europe. Equipments, antennas, history, SondeMonitor and BalloonTrack tutorials

1500 watts of RF output on the 70cm band requires robust amplifier design, a challenge addressed by this project featuring the GS-23b / 4CX1600U Svetlana tube. The resource details the construction of a high-power UHF amplifier, providing insights into component selection and layout necessary for stable operation at these frequencies and power levels.

Details the construction of an **HF converter** designed by M1GEO, George Smart, specifically to extend the frequency range of the FunCube Dongle Pro (FCD) for amateur radio reception. The FCD natively covers 64 to 1,700 MHz, but this project enables reception from 0 Hz to 64 MHz by up-converting signals to the FCD's operational range. It employs a **double-balanced mixer** with a 100 MHz local oscillator (LO) to translate incoming HF signals; for instance, a 1 MHz signal appears at 101 MHz within the FCD's passband. The design incorporates a 7th-order Chebyshev low-pass filter with a 62 MHz cutoff frequency at the input to mitigate image frequencies, ensuring cleaner spectral presentation. George provides the schematic, PCB masks, and Gerber files for replication, noting that Far Circuits also offers PCBs. The resource includes test results for the low-pass filter and measurements of LO leakage, identifying -36.8 dBm at 100 MHz as a potential sensitivity concern. M1GEO discusses potential improvements, such as adjusting the mixer's LO drive, adding a balance pot, or incorporating a post-mixer high-pass filter to reduce LO breakthrough. Audio recordings from 40m and 17m demonstrate the converter's performance with WRplus SDR software.

Short description of the olivia mfsk mode and explanation of how to use olivia mode and proper radio setup including recommended olivia frequencies

The _ISS Detector_ Android application, with over 5 million downloads, offers precise predictions for visible passes of the International Space Station. It notifies users minutes before an overhead pass, integrating local weather conditions to ensure optimal viewing opportunities. The core functionality focuses on the ISS, but in-app purchases extend its capabilities to track other celestial and artificial objects. Optional extensions, available via in-app purchase, allow users to monitor dozens of amateur radio and weather satellites, providing real-time transmitter information and Doppler frequencies. Additional extensions cover _Starlink_ satellites, the _Hubble Space Telescope_, rocket stages, bright satellites, comets, and planets, expanding the scope beyond the ISS to a broader range of observable space phenomena. The app's interface is designed for ease of use, displaying pass times, directions, and elevation. It adapts predictions based on the user's GPS location, ensuring accurate local forecasts. The latest update, dated April 3, 2026, includes corrections for magnitude values and various speed and stability optimizations.

Provides broadcast times, frequencies and power of the network emissions. Airs mediumwave, FM, shortwave and RealAudio broadcasts

This resource, a blog from the Penang Amateur Radio Club (PARC), offers insights into various aspects of amateur radio in Malaysia. One post details monitoring Automatic Terminal Information Service (ATIS) on the 2m band, providing specific frequencies like 122.750 MHz AM for Butterworth and 126.400 MHz AM for Penang, along with sample aviation weather and operational data. Another entry critiques the lengthy and costly process of obtaining an amateur radio license in Malaysia, contrasting it with the more streamlined FCC licensing system in the United States, citing a 1-year wait and RM 414 (USD 125) for 10 years in Malaysia versus 3 weeks and USD 14 for 10 years in the US. The blog also covers internal club matters, such as the 2007 Annual General Meeting (AGM) attendance and council elections, highlighting member dissatisfaction with outdated newsletters and a call for "reformasi." Additionally, it presents local phonetic alphabets in Bahasa Malaysia and Chinese, and discusses monitoring AM broadcast bands for international stations like Voice of America on 1575 kHz and Zhong Yang Ren Min Guang Bo Dian Tai on 1134 kHz, offering alternatives to local 2m repeater chatter. The author, "firstclass," shares personal observations and criticisms regarding the Malaysian ham radio landscape.

This handy and cheap portable dipole can be folded and backpacked, carried in use, and adjusted to a very wide range of frequencies.

The GB7MBC resource provides real-time DX spotting information through both web and **telnet cluster** interfaces, catering to amateur radio operators seeking immediate updates on propagation and station activity. It integrates features such as a **JOTA cluster**, RBN (Reverse Beacon Network) data, and PSK Reporter spots, offering a comprehensive view of current band conditions and DX opportunities across various modes and frequencies. The platform also includes a forum for community interaction and detailed DX cluster statistics, allowing users to analyze historical spotting data. Users can access the cluster via a standard web browser or through a telnet client, providing flexibility for different operating environments. The inclusion of RBN and PSK Reporter data enriches the spotting experience by cross-referencing reported signals with automated reception reports, enhancing the reliability and utility of the DX information. This combination of real-time data, community features, and statistical analysis makes it a practical tool for DXers and contesters.

KB9AMG's Top WSPR Spots presents a focused online tool for monitoring **2-way WSPR reports**, specifically detailing propagation data from February 2026 through March 2026. This resource aggregates _WSPRnet_ data, allowing radio amateurs to observe weak signal propagation conditions across various bands. The interface is straightforward, presenting callsigns, frequencies, signal-to-noise ratios, and distances for each reported contact, which is crucial for understanding current band openings and signal paths. The utility of this WSPR spotter lies in its ability to quickly visualize global propagation. Users can identify active stations and assess signal viability over long distances, with reports often showing contacts spanning thousands of kilometers. For instance, a typical WSPR report might indicate a signal from Europe reaching North America with a _SNR_ of -25 dB, demonstrating effective low-power communication. This data is invaluable for planning DX operations or evaluating antenna performance under actual propagation conditions.

A reference table of frequencies where you may find AM operations activity

Operating the AO-51 amateur radio satellite with a handheld transceiver (HT) presents a practical entry point for newcomers to satellite communications. This resource details the necessary steps and considerations for making basic contacts, focusing on accessible equipment. It covers fundamental concepts such as _Keplerian elements_ for satellite tracking and the importance of understanding Doppler shift effects on both uplink and downlink frequencies. The tutorial outlines a straightforward approach to satellite passes, emphasizing the use of readily available gear. It provides insights into antenna orientation and timing for successful two-way communication. The content aims to demystify satellite operation, enabling operators to achieve their first **AO-51** contacts with minimal specialized equipment. Key aspects include frequency management and basic operational techniques.

The BTech DMR-6X2 dual-band DMR handheld radio is thoroughly reviewed, detailing its features and performance for amateur radio operators. This resource covers the radio's capabilities for both VHF and UHF frequencies, supporting Tier II DMR digital and FM analog modes. It highlights key specifications such as its **136-174 MHz** and **400-480 MHz** frequency ranges, CTCSS/DCS, DTMF, 2-TONE, and 5-TONE signaling, and its _digital simplex repeater_ function. The review provides a comprehensive unboxing experience, listing included accessories like two Li-Ion batteries (2100 and 3100 mAh), a programming cable, and a 37-page English user guide. It also specifies the radio's physical dimensions of 5.1 x 2.4 x 1.5 inches and weights of 9.9 oz with the 2100 mAh battery and 10.8 oz with the 3100 mAh battery, offering practical insights for hams considering this transceiver.

The resource provides coaxial cable attenuation data, listing signal loss in dB per 100 feet for various cable types across a frequency range from 1 MHz to 5.8 GHz. The initial table details attenuation for cables such as _RG-58_, _RG-8X_, and RG-213, with impedance values of 50 ohm or 75 ohm, at frequencies up to 1 GHz. For example, _RG-58_ exhibits **0.4 dB** loss at 1 MHz and **21.5 dB** loss at 1 GHz per 100 feet. A subsequent table expands on this data, including LMR series cables like _LMR-400_ and LMR-600, along with other types such as 9913F7 and RG214. This section covers frequencies from 30 MHz to 1,500 MHz, also noting the outer diameter of each cable. For instance, _LMR-400_ (0.405" diameter) shows **0.7 dB** loss at 30 MHz and 5.1 dB loss at 1,500 MHz per 100 feet. The final section focuses on VHF/UHF/Microwave amateur and ISM bands, presenting attenuation in dB per 100 feet (and meters) for frequencies including 144 MHz, 450 MHz, and 2.4 GHz. This table includes larger diameter hardline options like 1/2" LDF and 7/8" LDF, in addition to flexible coaxial cables. For example, 1/2" LDF cable demonstrates **0.85 dB** loss at 144 MHz and 6.6 dB loss at 2.4 GHz per 100 feet. DXZone Focus: Coaxial cable attenuation | LMR-400 | RG-58 | 5.8 GHz

Presents a concise guide for Amateur Radio operators participating in Jamboree-on-the-Air (JOTA), an annual event connecting approximately 500,000 Scouts and Guides worldwide via ham radio. The resource details how to initiate a voice contact, including the use of "CQ Jamboree JOTA" and proper signal reporting with the RST system. It also outlines the typical exchange information, such as name, QTH, Scout rank, and age, encouraging participants to practice their responses. Authored by Bill Wetherill, N2WG, the brochure provides a practical phonetics chart and a comprehensive Morse code dictionary, including punctuation and prosigns like AR and SK. It clarifies rules for third-party operation under the direct supervision of a licensed operator, noting restrictions on international contacts without specific government agreements. Additionally, the guide lists recommended World Scout Frequencies for SSB and CW across 80, 40, 20, 17, 15, 12, and 10 meters, emphasizing courteous operating procedures. It includes a section on common Q-signals like QRM, QRN, and QSL, alongside the Amateur's Code, which stresses considerate, loyal, progressive, friendly, balanced, and patriotic conduct.

This article reports and collect some frequencies used during 2020 Ukraine war and reported as being used by army forces. HF communications are still a crucial part of military communications and can ben monitored on web sdr radios available on the internet.

Information about Venezuela, frequencies, maps, photos, history, and related links

Amateur radio operators seeking local community and emergency communications involvement often look for active clubs. The Rock River Radio Club (RRRC) provides a platform for hams in Wisconsin to participate in weekly nets and monthly meetings, fostering camaraderie and operational readiness. Their activities include regular ARES/RACES nets, which are crucial for maintaining proficiency in emergency communication protocols and equipment. The club hosts weekly nets on both VHF/UHF and HF bands, allowing members to practice various modes and frequencies. These include a Monday evening net on the Juneau Repeater at _146.64 MHz_ (PL 123.0) and a Thursday evening net on the Knowles Repeater at _442.975 MHz_ (PL 123.0). An HF net operates on Saturdays at **3.947 MHz**, with an additional ARES/RACES net on Sundays at **3.967 MHz**. Monthly club meetings are held on the first Tuesday of each month at 7 PM in Randolph, Wisconsin, providing a consistent gathering point for members and prospective hams. The club also engages in public demonstrations, such as those at the Experimental Aircraft Association (EAA) Dodge County Chapter Fly-In, showcasing amateur radio to a broader audience.

Dxpedition information site has dates, frequencies, operators etc. Planning a searchable data base for logs.

How to build Fan-Dipoles by DK7ZB. Experiences with various band combinations. Not all combinations are working properly. If the frequencies are to close together the impedances will lead to a very bad SWR. This happens with the bands 10-12-15m or 15-17-20m.

The article, "Using 75 Ohm CATV Coaxial Cable," details methods for employing readily available 75-ohm CATV hardline in standard 50-ohm amateur radio setups. It addresses the inherent impedance mismatch and practical considerations, such as connector compatibility, for hams seeking cost-effective, low-loss feedline solutions. The resource specifically contrasts common 50-ohm cables like RG-8, RG213, and _LMR-400_ with 75-ohm hardline, highlighting the latter's lower loss characteristics, particularly at VHF and UHF frequencies. It explores two primary approaches to manage the impedance difference: direct connection with an acceptable SWR compromise and precise impedance transformation. The direct connection method acknowledges that a perfect 1:1 SWR is not always critical, especially when using low-loss coax. For impedance transformation, the article explains the use of half-wavelength sections of coax to reflect the antenna's 50-ohm impedance back to the transmitter, noting its single-frequency effectiveness. It also briefly mentions transformer designs using toroid cores and a technique involving two 1/12 wavelength sections of feedline for broader bandwidth. The content further clarifies the concept of _velocity factor_ for calculating electrical versus physical cable lengths, providing a generic formula for precise length determination. It notes that while half-wave matching is practical for 10 meters and above, it can result in excessively long runs for lower bands like 160 meters, potentially adding **250 feet** of cable. The article also mentions achieving a usable bandwidth of 28.000 MHz up to at least **28.8 MHz** on 10 meters with specific transformation techniques.

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.

How to program Baofeng handheld transceiver with satellite frequencies, and how to get alerts when satellites are visible by using a smartphone app. A beginners guide to work satellites with a common VHF handheld radio.

National communications Family Radio Service frequencies divided in 14 channels

Airband Frequencies collection in french PDF files by SWL FE10262

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.