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This resource presents the _FCC_ Online Table of Frequency Allocations, codified under 47 C.F.R. § 2.106. The document details frequency assignments across the electromagnetic spectrum, from 0 kHz to beyond 2170 MHz, specifying allocations for various radio services including amateur, maritime mobile, aeronautical radionavigation, and broadcasting. The table is structured with columns for International Table (ITU Radio Regulations Article 5, Section IV, 2019 Edition), United States Table (Federal and Non-Federal), and corresponding _FCC_ Rule Part(s). Specific frequency ranges, such as **135.7-137.8 kHz** and **472-479 kHz**, are identified with their primary and secondary allocations, including Amateur Radio (Part 97) and Maritime Mobile (Part 80). The methodology involves direct publication of regulatory data, reflecting amendments adopted by the _FCC_ that may not yet be codified in the Code of Federal Regulations. Each entry provides the allocated service (e.g., METEOROLOGICAL AIDS, RADIONAVIGATION), relevant footnotes (e.g., 5.53, US18), and the applicable _FCC_ Rule Part. For example, the 1800-2000 kHz range is allocated to AMATEUR radio under Part 97, alongside MOBILE services. Contact information for the Office of Engineering and Technology Policy and Rules Division is provided for inquiries regarding the data. DXZone Focus: Regulatory Database | FCC Publication | Frequency Allocation | Rule Part Reference

HamCalc is a free collection of calculators for radio amateurs include Antenna ERP calculations, Attenuators, Audio Filter design, Coil Winding, Decibels, Great Circles map and calculator, HF Filters, HF Traps, Metric conversions OP Amps QRA Locator to Latitude/Longitude, Radio Horizon calculator, Resonance Satellite orbit calculator Timer calculations (555 timer)Zener Diode calculations Download zip By G4VWL

Explains what amateur radio entails, detailing its dual role as a hobby and a public service, enabling communication among licensed operators using diverse radio equipment for self-training, recreation, and public service. It clarifies that ham radio operators require a government license, regulated globally by the ITU via the IARU, and outlines the privileges and responsibilities that come with operating an amateur radio station, including restrictions against commercial use and broadcasting to the general public. The resource then enumerates various activities hams engage in, such as worldwide HF communication, local VHF/UHF contacts, QRP operation, Packet Radio, Amateur Television, Slow Scan TV, contesting, and satellite communications. It also covers emergency and volunteer services, traffic handling, and the process of becoming a licensed amateur radio operator in the United States, mentioning local clubs, Elmers, and self-study as preparation methods for the FCC multiple-choice test.

A 6 Mb PDF file of CQ Zones and ITU Zones and prefixes made available to download by Icom America.

Eight-channel Audio Spectrum Analyzer is a set of Real-Time Multi-Channel Gauges for investigation of data accepted from any ADC you will want or 16-, 24- and 32-bit ADC of sound card. WDM drivers support. FFT Spectrum Analysis, OscilloScope, Frequency counter, AC/DC voltmeter, Signal-to-Noise Ratio, Signal-to-Noise and Distortion, Spurious-Free Dynamic Range, Effective Number Of Bits, Total Harmonic Distortion, Inter-Modulation Distortion, Phase Shift. Special modes of dual-channel FFT spectral analysis: Separate channels spectra, Spectra of digital sum, difference, product of two signals, Spectrum of digital product of original signal and its fundamental, Spectrum of Real and Complex Transfer Function, Cross Spectrum. Standart weighing of spectra according IEC and CCIR. Oscilloscope modes (for dual-channel ADC) are: original signals, sum, difference, dependence of one channel on another, amplitude distribution of input signals.

Calculates grid squares from latitudes and longitudes, the reverse, and calculates distances and headings from two sets of lat/long or grid square. Convert Grid Square to Lat Log and vice versa. Freeware for Windows

Examines the current geopolitical landscape of Armenia, offering detailed reports on regional developments and internal political discourse. The station, _Radio Azatutyun_, covers critical discussions such as the potential for conflict in September, with one source suggesting a "war is coming, it won't be delayed," alongside ongoing debates about Armenia-EU visa liberalization, which is projected to require "another 2-3 years" for completion. It also highlights the contentious rhetoric surrounding the Prime Minister's interactions with displaced persons from Artsakh. The resource delves into significant international relations, including discussions between Bayramov and Araghchi on regional situations, and Iran's denial of recent negotiations with the US. It also features updates on former President Trump's demands for an additional **$200 billion** for defense and his assertion that "regime change" in Iran is effectively underway. Further content includes analyses of drone attacks in Baku, the proposed new Constitution, and local issues such as the delayed reconstruction of Gyumri's central market and the persistent problem of Vanadzor's temporary kindergartens. The platform also hosts podcasts like "The Choice is Yours," exploring the reliability of pre-election polls.

A large jpeg DX World map that include ITU Zones, grid squares and prefixes. This high-resolution DX World Map is an essential tool for amateur radio operators. It clearly displays ITU zones, CQ zones, grid squares (Maidenhead Locator), and DXCC prefixes, helping you to plan QSOs, track propagation paths, and participate in global contests. Whether you are a seasoned DXer or a beginner, this map provides a clear, detailed view of the radio world, improving your station's efficiency and geographic awareness. Available in JPEG format, it's perfect for display

Here is a simple and easy to build antenna in a Delta Loop configeration that should make 10 and 12 meters lots more fun if you have a limited space situation o

Electronic World atlas for radio amateurs. DXCC and province prefixes, CQ and ITU Zones in the rectangular and azimuthal projections, continuous zoom and scrolling, Gray Line, city and island index, unique hierarchical prefix database. COM/OLE Automation for easy integration with 3-rd party programs.

Table of allocation of international Call Sign series

One common challenge in antenna systems is mitigating common-mode current on the feedline, which can distort radiation patterns and introduce RF in the shack. This project details a 1:1 balun design that ingeniously avoids traditional ferrite beads, often a costly component, by substituting them with steel wool. The steel wool, when integrated into the balun's construction, effectively attenuates unwanted RF on the outer braid of the coaxial cable, ensuring that the antenna radiates efficiently and as intended. The construction involves winding coaxial cable through a PVC former, with the steel wool strategically placed to provide the necessary common-mode impedance. This method offers a practical and economical alternative for hams looking to build effective baluns without the expense or availability issues associated with ferrite cores. The design principles focus on creating a balanced feed to the antenna, crucial for optimal performance of dipoles and other balanced radiators. Experimentation with such designs can lead to improved field results, particularly for those operating with limited budgets or seeking innovative solutions for their antenna systems. The simplicity of using readily available materials like steel wool makes this a compelling build for many radio amateurs.

The AZIMUTH program plots a world map in either azimuth (beam heading) or Mercator projections. If you specify your home location in latitude and longitude, the azimuth projection is centred on your location. The Azimuth map program can display Maidenhead grids - this is useful for 6m, 2m, and UHF DX communication display. Various features of the map are: Azimuth or Mercator projections , Maidenhead grid display, Simple map zooming, Print maps with adequate resolution up to one meter sized map

DXMaps.com presents a dynamic, real-time mapping service for amateur radio DX spots, integrating data from traditional DX clusters, _PSK Reporter_, and WSPR networks. The platform visually plots global QSO and SWL activity, enabling users to observe propagation conditions across various bands, from 2200m to >450 MHz. It offers distinct overlays such as the magnetic equator, gray line, moon footprint for EME, and VOACAP propagation predictions, providing a comprehensive view of radio wave behavior. The service allows granular filtering of displayed spots, including options to show only DX-Cluster data, PSK Reporter activity, or WSPR signals. Users can refine the map view by selecting specific bands (e.g., 160m, 20m, 6m, 2m), limiting spots to the last 15 minutes, or displaying only contacts exceeding **2600 km**. Additional features include the ability to toggle grid squares, aurora forecasts, and various amateur radio zones (CQ, ITU). Distinctively, the resource updates automatically every minute, ensuring current propagation intelligence without manual refresh. It also supports specialized views for EME, ionospheric scatter, and aircraft scatter, alongside FM DX and APRS activity. The platform emphasizes the importance of accurate locator information in DX spots to enhance data quality and offers a user manual and FAQ for guidance.

adsbScope is a freeware Windows application designed for processing _ADS-B_ (Automatic Dependent Surveillance-Broadcast) frames received from a compatible decoder. It identifies aircraft, calculates their real-time positions, and presents flight parameters in both alphanumeric tables and a graphical display. The software interfaces via a virtual COM port, receiving raw frames to provide detailed situational awareness, including a global coordinate grid, continental coastlines, over 4,000 **airport** locations, and major cities. Users can overlay OpenStreetMap tiles and view world state boundaries, with each tracked aircraft rendered with labels showing altitude, speed, heading, squawk code, and flight identifiers. When paired with the adsbPIC-decoder, adsbScope enables advanced hardware control, allowing users to toggle data filters for specific frames like DF17/18/19, adjust analog signal thresholds for reception fine-tuning, and manage system resets or bootloader activation directly from the PC. This functionality provides a customizable toolkit for hobbyist radar listeners, offering a robust alternative to commercial tools for processing aircraft data. The software displays up to **1090 MHz** transponder data and can track aircraft up to 250 nautical miles.

The ITU and CQ Zones Map is a printable two-page PDF provided by Icom, displaying the world divided into ITU and CQ Zones. The purpose is to assist radio amateurs in identifying and understanding these zones for communication purposes.

Over 70 international contests are supported by YPlog, a Windows-based logging and radio control program designed for amateur radio operators. This software integrates with various digital mode applications like _WinPSK_, _HamScope_, and _MMTTY_, facilitating partially automated log entry for modes such as PSK31, CW, and RTTY. It provides comprehensive logging capabilities including QSL label printing, beam headings, and dup-checking, alongside award tracking for DXCC, ITU/CQ zones, IOTA, Grid Locators, and Counties. The program offers advanced contesting features, including multi-multi or multi-2 networked operations with automatic log data sharing, multiple Cabrillo submission formats, and configurable CW keyboard layouts. Device support extends to TR-compatible CW keying, SO2R control with Top-Ten devices like the DX-DOUBLER, and internal W9XT digital voice keyer integration. YPlog is notable for its support of the _OK1RR DXCC_ country resolution files, providing a robust historical DX compendium. Beyond logging, YPlog includes two freeware utilities: one for computing design parameters for coaxial traps and another for displaying and printing azimuth and Mercator maps from the operator's QTH. The software runs on Windows 95/98/ME/NT/2K, with a recommended screen resolution of 1024x768. Registration costs **$50.00 US** to unlock all features, including full contesting capabilities and rotator control.

The Joystick antenna was used many years ago as an all band vertical HF antenna under restricted space situations that would cover from 80 meters thru 10 meters with a tuner and was a great commercial success Some hams even had success with it on 160 meters.

Audio Kit is a collection of four iphone applications which are essential for those working in audio and sound. A real time Spectrum Analyser, a Scope to display waveforms, an SPL Meter, and a sine wave Signal Generator.

A shorten Dual-Band Dipole with overall length of about 11 m. For this antenna traps are substituted by inductors, in order to cover the 10 & 40 m. Bands.

This high antenna require a large ground composed by 40 radials. It's not very handy expecially in windy situations but is very powerfull in pile-ups. In italian

HotPaw MorseDecoder, an iOS application, provides real-time translation of Morse Code audio signals into plain text, leveraging the device's microphone or headset input. It incorporates a DSP narrow-band audio filter, adjustable from 300 to 2400 Hz, to mitigate background noise and QRM, enhancing signal clarity for decoding. The application offers both an automatic decoding mode and manual controls for fine-tuning parameters such as audio filter frequency, WPM dot/dash speed, noise threshold, and Farnsworth timing. The WPM detection automatically adapts from 8 to 40 WPM, with a QRQ High Speed mode extending this range to 30-80 WPM for faster code. A built-in spectrogram aids in identifying the precise audio frequency of the CW tones. User feedback indicates effective performance with various transceivers like the Yaesu FT-857 and Icom IC-R8600, particularly when manual settings are optimized. The app's ability to visually tune stations within the passband and decode speeds beyond an operator's manual capability has proven beneficial during contests and general QRP operation.

A sensitive RF probe is very useful in a situation where an oscilloscope is not available

Modifying the _ICOM IC-706MKII_ transceiver for out-of-band transmit capability involves specific surface-mount device (SMD) removal on the main circuit board. This procedure enables transmit functionality from 0.5 MHz to 200 MHz, excluding the commercial FM-Wide broadcast band, significantly expanding the radio's operational frequency range. The modification requires careful handling of small components and a fine-tipped, low-wattage soldering iron. Prior to beginning, all programmed memories and initial setup configurations must be noted, as the modification process will erase them. The instructions detail the necessary tools, preparation steps, and the precise location of the two SMD diodes to be removed. These diodes are situated near an oblong crystal can and a test point labeled _CP3_ on the main board. Successful completion returns the unit to its default configuration, necessitating manual reprogramming of memory channels and initial settings. This project is suitable for operators with experience in SMD work and fine soldering.

Amateur Radio Ham Radio Maidenhead Grid Square Locator Map online. This map allow just a point and click to determine dynamically the correct six characters locator. Other functions allow to calculate the distances among two given locators, or coordinates. Hover over map, specify grid, or enter latitude and longitude to show grid and/or calculate distance. Map is powered by Bing Maps.

The image is a all in one map of ITU Zones displaying worldwide regions and zones. It provides information on ITU Regions at IARU website, aimed at radio amateurs and technical users. Image size is in hight resolution and jpeg format, free to download.

BEAM_DX is a free windows software for radioamateurs or radio listeners usage. It allows to point a directionnal antenna towards an azimuth, a locator, an international prefix or any other geographical position on earth predefined by its latitude and its longitude

Free Donwload of the PDF file of ITU and CQ zones of the world, made available by Icom America

CW decoder project that automatically adapts itself to the CW rate and may be employed for learning purpose substituting the traditional tone generator and offering the capability of displaying the keyed code.

A must read guide for all new and old operators. This document was originally written with the prime focus on DXing and pileup behavior. Suggestions by proofreaders have been implemented; the document is not as narrowly focused anymore as originally intended. It contains hints, tips and tricks for newcomers as well as old-timers. Additionally there are VHF/UHF operational matters, DX Cluster ethics, COPS, Conflict Situations and more.

The U.S. Amateur Radio Callsign Lookup service, hosted by the University of Arkansas at Little Rock (UALR), offers a direct interface for querying the FCC's amateur radio license database. This resource is specifically designed for rapid retrieval of licensee information, including callsign, name, address, license class, and expiration date, all critical data points for QSLing and contact verification. The underlying database is refreshed daily, ensuring that the presented information reflects the most current FCC licensing records available. This service distinguishes itself by its direct reliance on official FCC data, processed and maintained by a university institution, which lends a degree of authoritative accuracy to its lookups. Users can input a specific callsign to instantly access detailed license particulars, facilitating efficient station identification and record-keeping for DXers and contesters alike. The daily update cycle minimizes discrepancies often found in less frequently synchronized callbook services. The UALR callsign lookup functions as a straightforward, no-frills utility, prioritizing data integrity and accessibility for the amateur radio community. Its operational simplicity and consistent data refresh schedule make it a reliable reference for verifying U.S. amateur radio licenses.

This online tool will convert any street address into latitude and longitude and vice-versa by executing queries to several online mapping services like googlemap geocoder maporama terraserver and more by Stephen P. Morse

A small portable antenna tuner for HF and VHF bands by ON6MU

Proppy: Online HF propagation predictions using the ITU Recommendation P.533-13 Propagation Prediction Application.

HFCC manages and co-ordinates global databases of international shortwave broadcasting in keeping with International Radio Regulations of the ITU. Operational Schedule, available for free download and iteractive schedule

Amateur Radio Maps online mixer of different selectable layers, including DXCC references, IOTA references, ITU and WAZ Zones. Works with most web browsers make heavy javascript usage.

Amateur Prefix Maps by UT0UM updated with ARRL DXCC and ITU changes, available for download in PDF

That just about sums up many peoples attitude towards test equipment. Multimeter, SWR/Power Meter, Dip Oscillator, RF Signal Generator, Cathode Ray Oscilloscope

Free format input, User selectable usage of reports, counters for DXCCs, WWL, DOK/UK Counties/CQ/ITU/States/Provinces and more

Map of ITU and IARU Zones at hamatlas.eu

The Wireless Institute of Australia (WIA) provides an official directory and database of Australian amateur radio repeaters, detailing their locations, frequencies, and operational status. The resource includes downloadable files in PDF and CSV formats, along with a _Google Earth KMZ_ file for visualizing repeater sites across Australia, including Amateur, CB, and Marine repeaters. It also references external resources for various digital modes such as _IRLP_, _Echolink_, _D-STAR_, P25, Fusion, and DMR, providing links to their respective information sites. The WIA repeater data is cross-referenced with the _ACMA database_ to ensure accuracy, with updates typically occurring twice a year. The directory employs a color-coding system, where purple indicates repeaters carrying the WIA broadcast or callback channels, and a 'W' status denotes operational repeaters with the weekly WIA broadcast. The resource also outlines policies for removing unlicensed or non-operational repeaters from the PDF listing after specific timeframes, while retaining them in the CSV file for potential reinstatement.

Ballistic simulator "Orbit" allows the physical principles of the motion in the gravitational field of the Earth to be demonstrated and learned. You can calculate with this program the ballistic trajectories of the thrown bodies and orbits of spacecrafts and visualize the astroballistic situation on the flat map of the world and on the rotating globe in the real time

This free program displays the location of any locator on a map. It calaculates between two Maidenhead locators the distance (km and miles) azimuth longitude latitude Show the location, direction and distance as you move your mouse on a map! Graphical Locator Program, By ON6MU

DX Finder presents a real-time DX cluster service tailored for amateur radio operators engaged in DX chasing and contesting. The platform aggregates DX spots, Reverse Beacon Network (RBN) data, and PSK Reporter information, displaying current activity across various amateur bands. It provides a centralized interface for monitoring propagation conditions and identifying rare DX entities, aiding operators in making timely contacts. The service integrates multiple data streams to offer a comprehensive view of global amateur radio activity. Users can access real-time spotting data, which includes callsigns, frequencies, modes, and signal reports, facilitating efficient station operation. The inclusion of RBN and PSK Reporter data enhances situational awareness, allowing operators to assess band openings and signal paths more effectively. DX Finder supports both web and Telnet access, catering to different operational preferences. It also features a dedicated JOTA cluster, specifically designed to support the Jamboree On The Air event.

Processing a single RTTY signal from a transceiver's 3-kHz audio, GRITTY employs _Bayesian statistics_ for superior decoding accuracy compared to traditional trial-and-error methods. This approach not only decodes 5-bit Baudot codes but also calculates the probability of error for each bit, enabling features like color-highlighting unreliable characters and smart squelching based on error probability rather than signal amplitude. This allows decoding of very weak signals while suppressing strong, undecodable interference, resulting in minimal garbage text. The program intelligently analyzes decoded text, comparing similar callsigns bit by bit and merging probabilities using the Bayes formula. This often allows GRITTY to determine the correct callsign and place it on the call stack even when all received copies are corrupt. The same methodology is applied to correct errors in exchange numbers and CQ/DE keywords, and to fix incorrect shift states. GRITTY offers an open API interface, documented in its Help file, for integration with other programs, allowing them to receive decoded data and mouse click events.

Despite the title referencing the callsigns 3C5J and MW0BRO, the content of this resource focuses entirely on the _Cleddau Computer Clinic_, an IT services company operating in Pembrokeshire since 1999. The site outlines a broad range of computer-related services, including custom-built new PCs starting from £399, sales of used systems, and comprehensive repair and upgrade options for existing units. Services extend to anti-virus and spyware removal, system installation, and broadband connection setup. The clinic also provides tuition for hardware and software applications, website design, and video to DVD transfer. They specialize in both fixed and wireless network solutions, enabling clients to share files and broadband connections efficiently. Repairs can be conducted either in their workshop or at the client's home or office, offering flexibility. For situations where on-site repair is not feasible, the Cleddau Computer Clinic offers a temporary replacement computer service. This includes transferring essential data to minimize disruption, a practical approach for local businesses and individuals in areas like Pembroke, Milford Haven, and Haverfordwest.

Over 47 full-screen maps are available within _NAOMI_ (North American Overlay Mapper), a free Windows program designed for US and Canadian amateur radio enthusiasts. This mapping suite includes 9 backgrounds such as CQ Zones, ITU Zones, and ARRL Sections, along with 16 foreground layers like Counties, Areacodes, and Grid Locators. Users can calculate distances and bearings, track real-time mouse positions with continuous Grid-Locator data, and integrate with APRS for live station tracking via the FindU database. For a global perspective, the _Global Overlay Mapper_ (GOM) provides a world map, 8 continental maps, and 29 sub-continental maps, all with 12 active layers including Country Outlines, CQ/ITU Zones, and Prefix information. Both NAOMI and GOM offer feature-locate systems to jump to positions based on prefixes, capital cities, or Grid Locators, and provide customized beam headings and distance displays. The site also features _LogView_, a post-contest log visualization tool that analyzes Cabrillo-format logs by plotting QSOs on maps, supporting over 30 major contests like CQWW and ARRL DX, and allowing comparison with published results.

Many NDB radio enthusiasts publish their reception logs on the web. A completely separate system designed for individual listeners to make their own logs and obtain statistics on NDBs, DGPS and now Navtex Stations they have received. Log listings can be exported in a multitude of formats and then emailed to the NDB List

This program allows both great-circle (polar) and rectangular projections of the world. The great-circle map is centered on any specified latitude and longitude (the "home" location). The rectangular projection is shown with the home longitude in the middle of the screen.

A scanned PDF of this interesting book on HF Dipole antennas published by Stanford Research Institute