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iSDR is a software defined radio application compatible with the Apple iPhone, iPod touch and iPad. iSDR is designed for experimenters, shortwave listeners, and amateur radio enthusiasts who would like a truly portable software-defined radio receiver.

Over 30 distinct shortwave (SW) receiver models are reviewed, offering insights into their performance, features, and user experiences. These evaluations, contributed by readers of the Usenet newsgroup **Rec.radio.shortwave**, cover a wide array of portable and tabletop radios, including popular units like the Grundig YB-400, Sony ICF-SW77, and various Realistic DX series models. Each review details aspects such as frequency range, tuning steps, SSB functionality, antenna performance, and construction quality, often comparing them to other receivers or ham transceivers like the Icom 725. For instance, the Grundig YB-400 review highlights its 144-30000 kHz AM/SSB coverage, direct keypad entry, and 40 station memories, noting its useful narrow bandwidth and tone switch for adjacent signal separation. It also discusses the **SSB mode** stability and the limitations of its 1 kHz frequency resolution for precise zero-beating. The review further details antenna performance, including the effectiveness of the built-in whip, the provided 7m reel antenna, and the potential for overload with larger outdoor antennas. Other reviews delve into specific issues, such as the Sony ICF-SW77's frequency display inaccuracies and timer malfunctions, or the Realistic DX-342's compact size and surprisingly good MW DXing capabilities despite its analog tuning. The collection provides practical, user-generated feedback on sensitivity, selectivity, audio quality, and ergonomic features, helping shortwave listeners understand the real-world performance and quirks of these receivers.

The resource provides detailed information about a five-band indoor magnetic loop antenna designed for amateur radio operators. This antenna is capable of operating on the 20, 17, 15, 12, and 10 meter bands, making it a versatile choice for various HF communications. Constructed from a single 3-meter length of 22 mm copper tube, the design emphasizes compactness and efficiency, which is particularly beneficial for operators with limited space. The page includes insights into the construction process, tuning, and operational tips, catering to both novice and experienced users. In addition to the technical specifications, the resource also discusses the advantages of using a magnetic loop antenna indoors, such as reduced interference and improved performance in urban environments. It serves as a practical guide for those interested in building their own antenna, offering a straightforward approach to antenna design and construction. Overall, this resource is a valuable addition to the toolkit of amateur radio enthusiasts looking to enhance their station with an effective indoor antenna solution.

Search for schedule of radio programs by selecting the language

This web page describes a small, single tuned circuit regenerative receiver primarily for daylight reception in the 16, 19, 22 and 25 meter international shortwave broadcast bands.

The directory lists several files, including `_template1.html` and `_template2.html`, last modified in 2006 and 2004 respectively, indicating a historical web project. Key scripts like `hfcc_cfm.pl` and `index.cgi`, updated in 2011, suggest a **CGI-based application** for searching shortwave broadcast schedules. The presence of `_template1.tpl` and `_template2.tpl`, both modified in 2015, points to a templating system for dynamic content generation. The file `hfcc_create-fill_mys..>` (likely `hfcc_create-fill_mysql.pl`) implies interaction with a database, possibly MySQL, for storing and retrieving **HFCC (High Frequency Co-ordination Conference)** schedule data. The `lang.cgi` script, last updated in 2002, suggests early support for multilingual interfaces or language-specific content delivery. The `q.txt` file, a small 804-byte text file, could be a query log or a simple data file. The overall structure indicates a system designed to process and present shortwave broadcast information, likely by querying a database of scheduled transmissions on various HF frequencies. The file modification dates suggest the project was actively developed and maintained over a period spanning more than a decade, with core components last updated around 2011 and templates in 2015.

A double bazooka antenna plan for the cw portion of the 40 meter band

A cost effective current-mode 1:1 balun can be constructed from a length of coax and a rod typically used for a broadcast antenna loop-stick, some electrical tape, cable ties, a length of PVC water-pipe and some connectors.

Complete introduction to amateur radio, excellent resource for beginners.

SSTV program for the Linux platform with several functions written by ON1MH Johan. QSSTV is a Linux-based program for receiving and transmitting SSTV (Slow Scan Television) and HAMDRM (Digital SSTV) signals, compatible with MMSSTV and EasyPal. Key features include support for narrow band SSTV modes, gallery functionality for viewing received/transmitted images, repeater capabilities for both SSTV and DRM modes, PulseAudio direct interface, and CAT radio control. The software includes waterfall visualization, hybrid mode operation, and template editing features. QSSTV requires Qt5 and several other libraries for compilation, and operates with a three-window interface for receive, transmit, and gallery functions.

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.

The page provides detailed information about the construction of a full-size 160M 3 element beam antenna and an 80M 5 element beam antenna on a 330ft tower. It includes specifics about the tower height, types of antennas, elements, gain, take off angles, front-to-back ratio, operating frequencies, weight, and dimensions of the beams. The content is aimed at amateur radio operators interested in building high-performance antennas for the 160M and 80M bands. This Antenna is now been destroyed and is no more operational.

GlobalTuners provides access to web controlled receivers. Listen to Ham radio, Tune Shortwave radio, Listen to Air traffic control, experience Airband receptio including ACARS and Airports. Tune remotely controlled receivers all over the world with your browser and get live audio.

Kantronics produce Modems, Tnc, Kam, Marine, wireless modems. Packet radio communication devices, HF E-mail, paging, GPS tracking, weather data gathering, or wireless data transmission.

A 2 meter power amplifier

Presents a catalog of **QRP** transceivers, antenna tuners, and related accessories for amateur radio operators. The product line includes the ZM-2 antenna tuner, designed for efficient impedance matching across HF bands, and the NW-series QRP transceivers, offering low-power CW operation. Additionally, the site details various ladder line insulators and specialized connectors, emphasizing robust construction for field deployment and home station use. Each product listing provides specifications, operational parameters, and pricing information. Compares the features of different **QRP transceiver** models, such as the NW-40 and NW-20, highlighting their respective band coverage and power output capabilities. The ZM-2 tuner's performance is detailed with typical SWR reduction figures for various antenna types, demonstrating its utility for portable and fixed stations. Customer testimonials and product images illustrate the practical application and build quality of EMTECH's offerings, providing insights into their durability and ease of integration into existing amateur radio setups.

Home of the ultimate Ham Radio QSL Label Program! Quick QSL for DOS, featuring great color, dot matrix, laser, and inkjet printer support, a user-friendly interface,

U.S. Government's military handbook on grounding in pdf format

The cobweb antenna it is basically a 5 band antenna comprising of 5 full half wave dipoles for each band - between 10 meters and 20 meters, the antenna is also resonant on 6M and can be modeled even for VHF frequencies.

A simple dual band VHF UHF jpole antenna Projects by Dale Kubichek

Amateur radio clip art for web pages, desktop wallpaper, newsletters and more!

Benefits and limitations of an end feed antennas. By Peter Parker VK3YE - first appeared in Amateur Radio, June 1998

We worry a lot about Standing Wave Ratio (SWR) in amateur radio since SWR is one indication of how well our antenna system is working. Most HF transceivers and antenna tuners have built in SWR meters. SWR is a measure of a transceiver' s output power verses the portion of that power reflected by the antenna system

This improved multiband trap dipole introduces a new trap design and a change in trap location. The antenna features double-coaxial-cable-wound traps having lower reactance and a higher quality factor (Q) than earlier coax-cable traps by W8NX

Duplexers for dual band radio are usually high pass filter and low pass filter combined in the same box. This circuit is a design within a cost of US$10.

The NCDXF/IARU International Beacon Project schedule provides precise transmission start times for 18 beacons operating on 14.100 MHz, 18.110 MHz, 21.150 MHz, 24.930 MHz, and 28.200 MHz. Each beacon transmits every three minutes, cycling through its callsign at 22 WPM followed by four one-second dashes. The initial callsign and first dash are sent at 100 watts, with subsequent dashes at 10 watts, 1 watt, and 100 milliwatts, enabling **propagation analysis** across varying signal strengths. The schedule lists the minute and second within each hour for the first transmission of each beacon on its respective frequencies. This resource allows **DXers** and **contesters** to accurately predict beacon transmissions for real-time propagation assessment. For example, 4U1UN transmits first at 00:00 on 14.100 MHz, followed by VE8AT at 00:10, and W6WX at 00:20, continuing the sequence. The page also notes recent hardware upgrades, such as the installation of IBP 2.0 controllers with Icom 7200 radios at some sites, and provides status updates for beacons experiencing hardware failures or those not recently heard, aiding in troubleshooting and managing expectations for monitoring.

You'll find more than 330 Amateur Packet Radio Gateways on world maps.

This resource provides a historical listing of **unlicensed amateur radio beacons** active in the United States as of December 1993, specifically detailing both **LOWFER** (Low Frequency Experimental Radio) and **MEDFER** (Medium Frequency Experimental Radio) operations. The data includes beacon frequencies in kilocycles (Kc), identification codes, state locations, and the callsigns or names of the beacon operators. Frequencies range from 166.667 Kc for LOWFER to 1706.0 Kc for MEDFER, illustrating the spectrum utilized by these experimental stations. The information was originally compiled by Mark Burkart and relayed to the rec.radio.shortwave newsgroup by Rick Robinson, KF4AR. The list serves as a snapshot of experimental beacon activity from the early 1990s, offering insight into the types of operations and the individuals involved in unlicensed, low-power transmissions. It highlights specific beacon IDs like "ABC SC" on 510.5 Kc and "GK HI" on 1620 Kc, alongside operator details such as Todd Roberts (WD4NGG) and Herb Vanderbeek (WY6G). While not a current operational guide, it is a valuable historical document for those interested in the evolution of LF/MF experimental radio and the early days of internet-based amateur radio information sharing.

This project details three variants of a vertical half-wave antenna design for the 4-meter (70MHz) amateur radio band. The antennas use end-feeding with a parallel-tuned circuit for impedance matching to 50-ohm coaxial cable. The first variant uses suspended flexible wire for portable use, the second employs a fiberglass rod with internal wire for permanent outdoor installation, and the third utilizes aluminum tent poles for quick mobile deployment. Despite the narrow bandwidth of the matching circuit, this suits the narrow 4m FM allocation well. The design offers an effective omnidirectional radiation pattern and can be constructed with readily available materials.

CW Skimmer 2.1 employs a high-sensitivity CW decoding algorithm based on Bayesian statistics, enabling simultaneous decoding of up to 700 CW signals within a receiver's passband on a 3-GHz P4 system when paired with a wideband receiver. The software features a fast waterfall display with sufficient resolution for visual Morse Code interpretation, automatically extracting and labeling callsigns on the waterfall traces. Extracted callsigns are exported as DX cluster spots via an integrated Telnet cluster server. The application includes a DSP processor with a noise blanker, AGC, and a variable-bandwidth CW filter, alongside an I/Q Recorder and player. It supports both 3 kHz radio passbands and wideband SDR receivers like SoftRock, RF Space SDR-IQ/SDR-14, SRL QuickSilver (QS1R), HPSDR Mercury, and Microtelecom Perseus. System requirements specify Windows XP/7/8/10 (32-bit or 64-bit), a Pentium-4 2.5 GHz for wideband operation or 1 GHz for 3-kHz radios, a COM port for CAT control, and a stereo sound card supporting 48 kHz sampling. It integrates with Elecraft KX3, Icom IC-7300/IC-7610, and Flex 6000 series radios, with documentation available for various setup configurations.

The article provides detailed instructions on how to build a half-sloper antenna for the 160 meters band. It explains the concept of a sloper antenna and how it differs from a slooper. The article includes practical tips on the construction and installation of the antenna to ensure optimal performance. The intended audience is amateur radio operators interested in building their own antenna for the 160 meters band. The content is informative, practical, and focused on DIY antenna building.

Some tens of very special audio files recorded during amateur radio activities like aurora traffic, meteor scatter, communications with ISS crew and the sound of various transmission modes that you can hear on HF and VHF bands

The SoftRock-40 is a small, low-cost, good-performing "software defined radio" receiver that plugs into a computer USB port and delivers I-Q audio signals to the computer's sound card. It was designed by Tony Parks, KB9YIG and Bill Tracey, KD5TFD as an "SDR sampler project" for hams everywhere to easily try out software defined radio.

HF Vertical and Beam Antennas, antennas accessories by Butternut. Bencher is out ouf ham radio business. Recently company products has been sold to Vibroplex and DX Engenieering.

The page provides a detailed guide on building a successful 160 Meter short TX loop antenna, with specific dimensions and tuning instructions. It includes information on the design, construction, and tuning of the antenna, as well as the materials required. The intended audience is amateur radio operators looking to build an effective antenna for the 160 Meter band.

AirLink Express is a user friendly digital mode software package for the Amateur Radio Operator. The software is compatible with Microsoft Windows XP and Microsoft Windows Vista. It offers PSK, MFSK and RTTY digital modes with logging and macro capabilities. If you have ever used the Digipan software you will be immediately familiar with Airlink Express. The user interface is almost identical by Alex Krist, KR1ST

FBB is a freeware bulletin board software for amateur packet-radio run on DOS Windows and Linux

An amateur radio web site serving the notorious 147.435Mhz Repeater in Los Angeles. Listen to the Shoutcast Live Streaming Audio.

RXCLUS is a free windows amateur radio software especially designed for the DX'ers and SWL's wanting to receive the informations transmitted by packet radio on the DX-cluster system. It supports also telnet protocol.

Demonstrates BBLogger, a **freeware** logging application designed for both amateur radio operators and Short Wave Listeners (SWLs). Developed by IK2VIW, IZ2BKT, and IK2UVR, this software provides comprehensive station management capabilities, including **CAT control** for various transceivers, integration with digital mode software like WSJT-X, JTDX, and MSHV, and robust QSL management features. The application supports a wide array of functions such as DX cluster interfacing, mapping, awards tracking (including custom awards), and direct integration with services like LoTW, eQSL.cc, and ClubLog for QSL confirmations and OQRS requests. It also includes utilities for ADIF to CSV conversion and vice-versa, catering to diverse logging and data management needs. Recent updates, such as version 13.1, introduce a web server for log management from any device, allowing remote access and control. The software has improved ADIF import capabilities, including time settings for duplicate QSO detection, and enhanced filtering options for log searches. Performance improvements include faster automatic updates and manager database synchronization, along with optimized log checking at startup. Earlier versions added support for FT8 and FT4 modes, refined OQRS integration with ClubLog, and expanded QSL/label printing functionalities, enabling users to select specific callsign types (OM, SWL) for printing. The developers emphasize compatibility with Windows 10/11 for full functionality, noting limitations when running on older operating systems like Windows 7 due to modern security protocol requirements.

HF Ham Radio antennas for apartments and methods of shortening antennas

Schematics, mechanical drawings and picture of a Receiving loop antenna by N5ESE - N5FC

Homebrew a vertical dipole for 28 Mhz by N2UHC

Catalogs a diverse array of Software Defined Radio (SDR) projects and realizations, systematically classified by their sampling methodologies and underlying hardware architectures. The resource delineates projects into categories such as those utilizing soundcard sampling of traditional transceiver audio outputs (Type Ia), mono soundcard sampling of intermediate frequencies (Type R1x-x-xx), stereo soundcard sampling of I/Q IFs (Type Q1x-x-xx), dedicated stereo audio ADC sampling of I/Q IFs (Type Q2x-x-xx), direct antenna RF signal sampling with off-the-shelf acquisition boards (Type R3x-x-xx), dedicated RF ADC sampling of analog IFs (Type R2x-x-xx), dedicated RF ADC sampling of direct antenna RF signals with ASIC-based processing (Type R4x-A-xx), FPGA-based processing (Type R4x-F-xx), and specialized IF chipsets combining ADC and DDC functions (Type Dxx-S-xx). Each entry provides a brief description, often including pricing, availability of source code, and specific hardware components like ADCs, DACs, DDS, and FPGAs. The compilation presents various practical applications, from PSK31 and Packet radio implementations to adaptations of the DRM standard for amateur radio bandwidths, such as Hamdream and WinDRM. It features specific hardware designs like the SoftRock-40 for the 40-meter band, the Firefly SDR for 30m and 40m, and more complex systems like the Quicksilver QS1R, which employs a 16-bit 130 Msamples/s ADC and an Altera Cyclone III FPGA. The resource also lists sample processing software, RF front-end designs, and academic/commercial SDR initiatives, offering insights into different approaches for I/Q conversion and digital signal processing in SDR systems.

Maritime frequencies and nets

Amateur Radio, Citizen's Band Radio, Commercial Radio, General Electronic items, Marine Radio, and Short Wave Radios.

Multiband Center-Loaded Off-Center-Fed Dipole (CL-OCFD) antenna that work on 80m 40m 30m 20m 15m 10m. The Center-Loaded Off-Center-Fed Dipole (CL-OCFD) antenna, developed by Serge Stroobandt, offers a versatile solution for amateur radio enthusiasts, covering multiple HF bands (80, 40, 30, 20, 15, and 10 meters) without the need for an antenna tuner. This innovative design utilizes a capacitor for resonance on the 80-meter band and a resistor to manage static charges. The CL-OCFD enhances bandwidth and simplifies operation, making it a significant advancement on OCF Dipole design.

4CX250B X2 K2RIW style 2m amplifier

A delta loop wire antenna plan for the 7 MHz band (40 meters) that is quick to setup and work with

A very easy to use program to decode DTMF dial tones found on telephone lines with touch tone phones. The DTMF Decoder is also used for receiving data transmissions over the air in amateur radio frequency bands.