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The web page provides detailed information on a portable 10/20/40 meter vertical antenna designed for mobile operations, including modifications for 20 and 40 meters. It includes images and descriptions of the antenna setup in a car. The content is useful for amateur radio operators looking to enhance their mobile communication capabilities.

SSTV freeware software for Windows by Mako JE3HHT. MMSTV is a free software application designed for transmitting and receiving SSTV (Slow Scan Television) images over HF bands. It allows radio amateurs to share still pictures using sound-card interfaces and a transceiver. The program supports popular SSTV modes (Martin, Scottie, Robot, etc.), real-time RX/TX monitoring, and easy image editing. Its user-friendly interface and reliability make MMSTV a favorite choice among ham operators worldwide. Ideal for showcasing QSL cards, shack photos, or technical diagrams over the ai An excellent SSTV program that requires only a computer with soundcard, no expensive TNC required. Works on all Windows version including Windows XP, Vista and Windows 7.

Select your favorite satellite and watch its trajectory on Google Maps in real time! Includes ISS tracking, Weather, Geostationary, GPS Military, and of course Amateur radio satellites. N2YO provides comprehensive real-time satellite tracking with particular emphasis on amateur radio satellites. The service offers precise pass predictions calculated for user-specific locations, displaying upcoming passes with azimuth, elevation, and duration data essential for ham operators planning satellite contacts. N2YO features dedicated tracking for amateur radio satellites including FM, linear transponder, and digital satellites, with frequency information and downlink/uplink details. The platform delivers live tracking visualizations on interactive maps, Doppler shift calculations, and automated email notifications for upcoming passes. This free resource integrates weather satellite tracking alongside NOAA imagery, making it invaluable for radio enthusiasts pursuing satellite communications.

HamAlyzer is a spectrum analyzer made just for hams, save plot images easily for emailing, monogramed with your call sign. HamAlyzer looks no more supported, here 2.8 trial version available. Download hamalyzer

Easy download your free high quality desktop image about amateur radio station and antenna

A large collection of maps of each dxcc country with general information, banknotes and coins, satellite images, flags and national information where available by SP6NVK

Images and technical details of thousands of transceivers, cb radios, rotators, rf amplifiers scanners and accessories, by SM0OFV

A coil loaded dipole antenna for 40 and 80 meters band by I2CN

Complete 144/50 MHz transverter with GaAs Fet LNA and 400 mW out. No printed circuit board. Schematics and images by Christoph Petermann DF9CY

EasyPal is a sophisticated digital Slow-Scan Television (SSTV) application that utilizes soundcard technology to encode and decode SSTV signals. Developed by the late Erik Sundstrup (VK4AES SK), this software has evolved into a versatile communication tool for amateur radio operators, extending beyond basic image transmission capabilities. EasyPal implements Digital Radio Mondiale (DRM) encoding technology, enabling efficient data transmission over narrow 2.5 KHz channels on both HF and VHF frequencies with remarkable speed. The application supports multiple file formats, including jpg, pdf, txt, doc, and xls, as well as specialized forms such as ICS-213 and ICS-213 (ARES). Additionally, EasyPal offers email functionality through designated repeater stations with internet access. Its responsive development history and robust feature set have established it as a premier digital SSTV solution in the amateur radio community, though users of Windows 11 should note specific configuration requirements to ensure optimal performance.

432 MHz EME low noise amplifier. Circuit, components and image by Christoph Petermann DF9CY

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.

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.

Manual for R7, 10 12 15 16 20 30 40 meters band antenna

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

FT857 and FT897 Interface PCB and schematic

A 20 meter quarter wave vertical antenna by jerry sevick W2FMI QST Article

A Google query for radio clip art

SolarHam is a website all about the Sun and how it affects Earth. This site is routinely updated with breaking news, sometimes hours before other Space News websites. You can trust SolarHam.com for the most up to date and accurate solar information on the net. SolarHam is a trusted and easy-to-use website for anyone interested in solar activity and space weather. It gives daily updates on <b>solar flares</b>, sunspots, geomagnetic storms, and radio blackouts. The site uses data from NOAA and NASA to show what is happening on the Sun and how it may affect radio signals on Earth. Charts and images are clear, and reports are updated often. Many amateur radio operators use SolarHam.net to check band conditions and aurora forecasts before operating. The site is fast, well organized, and focused on the needs of the radio community. Whether you are a beginner or an experienced ham, SolarHam.net is a helpful tool for understanding space weather and its impact on radio communications.

The Elecraft K3, a popular HF transceiver, is often benchmarked against new market entrants. This article critically compares the Kenwood TS-590S to the K3, focusing on key technical specifications and operational aspects relevant to serious amateur radio operators. The author proposes three distinct evaluation methods: a circuit diagram comparison, an independent review analysis (referencing Peter Hart, G3SJX, in RadCom), and a real-world "ear test" by experienced contest operators on 40 and 80 meters. The analysis delves into specific receiver components, including the first mixer design, RF and IF amplifier performance, and the presence of an image noise filter. It highlights the K3's switched mixer and the potential for the TS-590S to utilize similar or improved designs, such as a classic filter with enhanced selectivity. The article also scrutinizes the second mixer stage, noting the K3's SA612 chip and its associated IP3 limitations, suggesting Kenwood might achieve benefits with a different mixer architecture. Further points of comparison include DSP capabilities, where the K3's high-performing DSP with KK7P's involvement is noted against the TS-590S's potential reliance on newer IC technology but possibly less refined software. The discussion extends to DDS and PLL implementations for phase noise and spurious emissions, and the utility of a second receiver for DX chasing and contesting, acknowledging its importance for some operators while being less critical for others. The article concludes by emphasizing personal preference in equipment selection.

Demonstrates the construction of a **homebrew spectrum analyzer** designed by Wes Hayward, W7ZOI, and Terry White, K7TAU, enabling radio amateurs to build a capable test instrument without significant expense. The resource details a _double-conversion superheterodyne_ circuit, employing intermediate frequencies of 110 MHz and 10 MHz, and covers essential blocks such as the time base, logarithmic amplifier, resolution filters, and local oscillators. It highlights the use of hybrid and monolithic ICs, including mixers, amplifiers, and VCOs, to simplify construction while maintaining performance. The design supports useful measurements in the 50 kHz to 70 MHz range, with methods outlined for extending capabilities into VHF and UHF. The authors emphasize that this analyzer, while simple to build, is intended for serious measurements, requiring careful control of signal levels to avoid spurious responses. It uses an oscilloscope for display, with specific instructions for calibration and adjustment of various stages, including the log amplifier and IF gain. The guide provides detailed schematics and component lists for each section, such as the 110 MHz triple-tuned band-pass filter, which achieved **90 dB** image rejection, a significant improvement over double-tuned circuits. Practical advice on alignment and troubleshooting is included, drawing on the authors' extensive experience in RF circuit design.

TVI and BCI bandpass and bandstop filters in SMD technique. Schematics and images.

The mirror-image J-Pole is very easy to construct and requires only two T-Fittings plus a length of copper pipe.

Map of USA Districts

Stone vintage radio describes early radio from marconi to the 1960s. its covers antique radio, wireless, tubes, valves, crystal sets, and battery radios. included in the virtual museum are hundreds of pictures, images, and descriptions of antique radios, articles, faq, sell, and buy a radio.

The FL-2100Z amplifier referenced in the following images is the 6-Band model covering 10m thru 160m (no WARC bands) and not the 9-Band version that included the WARC bands. Modifications, schematics and manual

A few images to use as a desktop background.

For amateur radio operators running Microsoft Windows XP or later, Lux-Log provides a robust logging and contest software solution, designed by Norbert Oberweis, LX1NO. It is capable of managing over 30,000 logbooks within a single database and image copy, offering comprehensive data handling features. The software facilitates data import and export via **ASCII** and **ADIF** formats, ensuring compatibility with other logging applications, and includes an integrated tool for converting data from other programs into ADIF. It provides instant feedback on previous contacts and country information during data entry, alongside static or serial value generation for contesters. Lux-Log integrates a versatile award module, currently supporting 123 definitions for popular awards such as DXCC, WAZ, WAS, US Counties, IOTA, and more. Operators can generate pre-defined and user-definable data queries, visualize statistics through bar/pie charts, and print QSL labels. The software also interfaces with the RAC Callbook and HamQTH, supports LoTW, and offers radio control for Icom and Yaesu FT-857 transceivers. Additionally, it supports telnet connections to internet clusters and integrates with K1EL's WinKey for CW generation, making it a comprehensive tool for both general logging and contesting activities.

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.

A free windows SSTV receiving program specially designed for SWLers. This sstv decoder does not support SSTV TX. Automatic saving of images, based on MMSTV enigne, support multiple sound cards and advanced quality settings. This software is just capable to decode SSTV a good choice if you need to receive slow scan TV.

This resource catalogs a significant collection of historical military radio equipment, detailing various sets from World War II and the Cold War eras. It presents information on British, German, Japanese, USA, and other nations' wireless apparatus, including specific models like the _WS-19_, R1155, and WS-18, alongside clandestine spy equipment. The content covers the preservation and restoration of these historical items, with research results published on the site. The site provides dedicated sections for different national origins of equipment, such as "British sets," "German sets," and "North American sets," allowing for focused exploration of specific military communication technologies. It also features specialized pages on topics like the _Enigma machine_, PARASET builds, and historical events such as Arnhem and D-Day, contextualizing the use of these radios in significant military operations. The collection includes detailed descriptions and images of transmitters, receivers, and associated gear. The museum, located in Kidderminster, Worcs, U.K., organizes physical exhibitions and actively seeks new equipment for its collection, emphasizing its role in preserving military radio history.

FindU.com operates as a robust database archiving **APRS** (Automatic Packet Reporting System) data, including weather, position, telemetry, and message reports. It integrates data from both amateur radio APRS systems and the internet-based Citizen Weather Observer Program. This substantial 58 GB database is hosted on dual servers utilizing data replication, processing approximately 20 new reports per second to provide constantly updated information. The system supports various applications, such as displaying weather reports, tracking position data, and facilitating long-term vehicle tracking. A notable function involves forwarding over 100,000 near-realtime weather observations daily to the National Oceanographic and Atmospheric Administration (NOAA) for accuracy checks and use by NOAA and the National Weather Service. Additionally, it archives APRS reports from the International Space Station. Access to the database is primarily via dynamic web pages, with a comprehensive list of available CGIs detailed on a dedicated server page. While direct URL parameter editing is possible for advanced users, alternative web pages with forms simplify query submission. The platform utilizes **PNG** images for dynamic graphics, a choice made due to past GIF patent issues, ensuring broad browser compatibility.

Maldol MFB-300 all band HF vertical antenna review by Steve Nichols

Images and Radio Shack composition

Presents a detailed construction guide for a **Quadrifilar Helix Antenna** (QHA) optimized for 137 MHz, specifically for receiving weather satellite transmissions. The resource outlines the author's experience building previous QHA designs, highlighting challenges with tuning and nulls, and then focuses on a refined design by John Boyer, documented by Steve Blackmore, which proved easier to build and yielded superior reception. The guide provides precise element dimensions, including 1.5m of 32mm PVC pipe for the mast and 8mm soft copper tubing for the helix elements. It specifies lengths for horizontal tubes (190mm, 90mm) and helix elements (903mm, 1002mm), along with instructions for drilling, assembly, and forming a **balun** by wrapping RG58 coax around the mast. The text emphasizes critical steps like ensuring elements are square and twisting in the correct direction to avoid phase issues. It includes references to original QST articles by Buck Ruperto (W3KH) and the WxSat program for decoding satellite transmissions, contextualizing the antenna's purpose. The article concludes with a sample NOAA 12 image from September 1998, demonstrating the antenna's reception capabilities.

Operating Slow Scan Television (SSTV) on Apple macOS systems requires specialized software to encode and decode images for transmission over amateur radio frequencies. MultiScan 3B was an application designed for this purpose, enabling Mac users to engage in SSTV communications. It supported various popular SSTV modes, including Robot Black & Color, Scottie, Martin, PD modes (P3, P5, P7), and AVT, catering to a wide range of operational preferences and compatibility requirements within the SSTV community. The software's capabilities extended to both transmitting and receiving pictures, offering flexibility in how images were processed. Users could select regular, narrow, QRM, and narrow+QRM modes, allowing for adaptation to different band conditions and signal environments. This feature was particularly useful for mitigating interference and optimizing image quality during transmissions on HF bands. MultiScan 3B was built to run on Mac OS X 10.6 and later versions, providing a dedicated solution for Mac users interested in this classic digital mode. Its support for multiple modes and operational settings made it a versatile tool for SSTV enthusiasts.

If you are interested in the environment, the weather and other natural phenomena then there is something magical about being able to see pictures of the earth from space just as it is right this minute. One way you can do this is by receiving images from weather satellites.

Images of VHF UHF antennas

The TS850s connector pinouts for Mic,acc2, acc1 and remote connector

HF Weather Fax lets you receive marine weather radiofascimile transmissions on your iPad, iPhone and iPod Touch. Just connect it to a shortwave radio tune in a weather fax frequency, and watch the images come in.

General purpose image display and analysis program with special features for analyzing satellite images

A J-pole antenna plan made using a half inch copper tubing

Audio and waterfall images of some sounds found on the RF spectrum

ChirpPix converts a bitmap image to a wave file, which can then be sent by a SSB transmitter and received on spectrogram waterfall displays Image Transmission using ChirpPix and ChirpHell. Click to donwload ChirpPix zip file.

AirNav live. See live images from my AirNav Radar box here in Clacton on Sea, Essex. Also full setup details.

A trapped dipole antenna based on the orignal W3DZZ antenna design resonating on 80 40 20 15 10 meters

DX_Central, a compact desktop application, provides amateur radio operators with critical propagation data by aggregating solar statistics and imagery from various authoritative sources. This includes real-time information from agencies like NOAA and NIST, offering insights into current space weather conditions that directly impact HF propagation. The software is designed for both Linux and Windows operating systems, making it accessible to a broad range of hams. It presents a concise overview of solar activity, which is essential for planning DX operations and understanding band openings and closures across the HF spectrum. Operators can utilize the displayed solar flux index, K-index, and other relevant parameters to make informed decisions regarding their operating times and target bands, optimizing their chances for successful long-distance contacts.

2 x GI7B in push-pull 2m and 6m 1kW Power amplifier from PA0ZH

The resource presents a detailed schematic for constructing a dual-band vertical antenna, specifically designed for operation on the 2-meter and 70-centimeter amateur radio bands. It illustrates the physical layout, critical dimensions, and component placement necessary for successful replication. Key elements such as the radiating elements, phasing sections, and feed point are clearly depicted, providing a visual guide for radio amateurs undertaking a homebrew antenna project. The diagram specifies the lengths for the VHF and UHF sections, indicating how these elements are integrated to achieve dual-band functionality from a single coaxial feedline. It also implies the use of common materials readily available to most experimenters, focusing on simplicity and effectiveness in its design. The visual format of a GIF image ensures direct access to the construction details without requiring extensive textual interpretation. This schematic serves as a practical reference for hams interested in building a compact, efficient vertical antenna for local and regional FM communications, offering a proven design for immediate implementation.

A set of utilities for the SSTV enthusiasts. SSTV signal generator, to generate SSTV audio signals from a bitmap. SSTV Signal Viewer to demodulate SSTV signals, anf SSTV Image Denoiser to removes noise from the pictures. By VE3NEA.