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WiNRADiO Communications, a division of Radixon Group, was established in 1996 to commercialize extensive research in radio communications. The company specializes in integrating radio and computing technologies, offering a diverse product range for government, military, security, and amateur radio enthusiasts. Their product line includes the WR-G65DDCe 'EXCALIBUR Sigma' HF/VHF SDR receiver, noted for its capabilities, and the G31DDC EXCALIBUR, recognized for its price/performance ratio in shortwave listening with improved AMS and Noise Blanker features. The company also produces the G39DDC series EXCELSIOR for serious monitoring, WR-G526e/G527e/G528e modular SDR solutions for high-performance applications like phase-coherent direction finding, and the low-cost WR-G305e/G305i VHF/UHF receivers. Professional counterparts, the WR-G315e/G315i, support APCO P25 decoders and trunking options. WiNRADiO's offerings extend to the PFSL-G3 field strength logging system for mobile signal coverage, advanced multichannel telemetry systems like the MS-8323, and specialized antennas such as the AX-31C Log-Periodic and AX-81S active HF antenna. DRM decoder software is available for G3 Series receivers, enabling clear reception of DRM broadcasts. The WSS-420 Weather Satellite Receiving System and various antenna rotators are also part of their product ecosystem. WiNRADiO supports multiple operating systems, with MacRadio for Apple Macintosh users and LiNRADiO for Linux developers, providing drivers and network receiver solutions like the RLX-810.

Presents the product lines and corporate information for Japan Radio Company (JRC), a long-standing manufacturer of radio communication equipment. The company's offerings span various sectors, including marine, land, and aviation communication systems, alongside their historical contributions to amateur radio with notable **HF transceivers** and **shortwave receivers**. JRC emphasizes its technological expertise in areas such as radar, satellite communication, and network solutions, contributing to global safety and security infrastructure. The resource details JRC's commitment to leveraging its accumulated knowledge and experience in information and communication technology. While the primary focus has shifted towards commercial and governmental solutions, the legacy of JRC's amateur radio products, such as the JRC JST-245 transceiver and the NRD-525 receiver, remains significant within the ham radio community, known for their robust build quality and performance.

Constructing a Lindenblad antenna for 137MHz NOAA satellite reception involves specific design considerations for optimal performance. The resource details the use of 4mm galvanised steel fencing wire, 300-ohm television ribbon cable, and wood/plastic components for the antenna structure. Key dimensions for a 137.58MHz-resonant antenna are provided, derived from the ARRL Satellite Handbook, specifying s, l, w, and d as 42, 926, 893, and 654mm respectively. The antenna is designed for Right Hand Circularly Polarised (RHCP) signals, requiring the four folded dipole elements to be tilted clockwise by 30 degrees. A significant aspect covered is impedance matching between the antenna's 75-ohm impedance and a typical 50-ohm receiver input. A twelfth-wave matching transformer, constructed from 117mm sections of 50-ohm RG-58 and 75-ohm RG-59 coax with a 0.66 velocity factor, is described. The article also addresses coaxial cable and connector selection, recommending 75-ohm Type-N connectors for RG-6 cable in professional setups and F56/F59 connectors for general use, while strongly advising against PL-259/SO-259 connectors for VHF. Strategies for mitigating Radio Frequency Interference (RFI) are discussed, including antenna placement to shield from local TV transmitters and the use of commercial or DIY band-pass filters, such as cavity resonators or helical notch filters, along with ferrite chokes on coaxial cables. Antenna orientation is explored, noting the Lindenblad's 'cone of silence' directly overhead and its maximized sensitivity towards the horizon. An experimental vertical tilt of 90 degrees is presented as a method to improve overhead reception and reduce interference from strong horizontal signals, particularly relevant in high RFI environments like the Siding Spring Observatory site.

a PREDICT client application written by Vittorio Benvenuti, I3VFJ, allows operation of an ICOM PCR 1000 receiver in a satellite communication environmenta PREDICT client application written by Vittorio Benvenuti, I3VFJ, allows operation of an ICOM PCR 1000 receiver in a satellite communication environmenta PREDICT client application written by Vittorio Benvenuti, I3VFJ, allows operation of an ICOM PCR 1000 receiver in a satellite communication environment

Packet-Radio-Controller for amateur radio, CB and commercial applications. Data radios (transceivers), receivers and transmitters for high speed data communication Assemblies for satellite ground stations, special receivers and transmitters.

C & Ku band satellite equipment - LNBs & LNBFs - MPEG-2 dvb receivers - dishes & More.

This type of filter can be used in a Mode J satellite station (uplink on 2m, downlink on 70cm) to reduce the problem of the uplink signal desensing the receiver

Decoding NOAA APT weather satellite images is achieved with a homebrew receiver and a Turnstile Cross Dipole antenna, feeding data to a Pentium-3 500MHz PC running Windows XP and the WXTOIMG program. This setup, operated by VU2IIA in Mumbai, India, focuses on capturing and processing signals from NOAA satellites to generate visual weather data. The blog documents the technical aspects of constructing the receiving station, including antenna design and receiver integration. It provides insights into the practical challenges and successes of amateur satellite reception, specifically for Automatic Picture Transmission (APT) signals. Operational details cover the software configuration and image processing workflow necessary to transform raw satellite data into usable weather imagery. The content serves as a practical guide for radio amateurs interested in satellite meteorology.

How to receive automatically NOAA wather satellite images with a Raspberry Pi and a RTL SDR. This project requires a Raspberry Pi 3 Model B a common NooElec SDR Dongle and a QFH Antenna in the attic. Article explains how to setup and configure software but no instructions on antenna.

The Doppler Effect allows the distance between a satellite transmitting from space and a radio receiver on the ground to be measured by observing how the frequency received from the satellite transmitter changes as the satellite approaches, passes overhead, and moves away.

Sixty-meter repeaters typically use a 1 MHz frequency separation between input and output, while 2-meter repeaters commonly employ a **600 kHz** split and 70-centimeter repeaters use a **5 MHz** offset. This article details the fundamental technical principles of amateur voice repeaters, explaining how they extend VHF/UHF communication range by receiving on one frequency and simultaneously retransmitting on another. It covers essential components such as receivers, transmitters, filters, and antennas, often situated on elevated locations for optimal coverage. The resource delves into the critical challenge of _desensing_—where the repeater's strong transmit signal overpowers its own receiver—and the engineering solutions employed, including antenna separation and the use of high-Q cavity filters. It also explores various control and timing systems, from basic squelch activation to more sophisticated microcontroller-based boards that manage functions like voice identification, time-out timers, and fault protection. Different access methods are discussed, including open access, toneburst, CTCSS subtone, and DTMF, each offering distinct advantages for managing repeater usage and mitigating interference. Furthermore, the article examines repeater linking, both conventional RF methods and modern internet-based solutions, highlighting how linking expands coverage and promotes activity across multiple repeaters or bands. It introduces less common repeater types such as 'parrot' repeaters, which use a single frequency and digital voice recording, and linear translators, capable of relaying multiple signals and modes simultaneously across different bands, often found in amateur satellites.

The MiniTioune receiver project, developed by Jean-Pierre F6DZP, consists of the home constructed MiniTiouner hardware which interfaces via a standard USB 2.0 port to a Windows PC running the MiniTioune software. It can be used to receive satellite broadcasts transmissions making it ideal for use on Q-oscar 100 Es hail-2 without any external frequency converters.

The ZL1WTT resource details an experimental software-based Digital Amateur Television (DATV) system, demonstrating the multiplexing of up to six standard-definition (SD) and one high-definition (HD) channel utilizing _h264 compression_. The author encountered peak data rates reaching 32 Mbit/s, necessitating a shift to Freeview and Sky settings (22.5M Sym/s 3/4FEC) to manage bandwidth. The setup employs four networked computers, with a laptop functioning as the multiplexer to re-code PIDs for various inputs, including looped MPEG2 playlists, MPEG2 encoder card input from a VCR, satellite feeds, and an off-air UHF receiver. The system highlights the inherent flexibility of the DVB transport stream, supporting diverse formats such as MPG2, h264, AC3, and AAC. A significant advantage of this software-defined approach is the absence of video quality degradation from stored MPEG2 files to the displayed output, coupled with the ease of reconfiguring settings for MPEG2 encoder cards (e.g., size, bit-rate, frame rate, video input, coding format) and satellite receiver cards (e.g., frequency, LNB volts, symbol rate, FEC). The author also discusses the development of a new graphical user interface (GUI) using _Gambas_ for Linux, aiming to simplify configuration for this DATV project. Specific hardware components mentioned include Hauppauge WinTV PVR-150 and Nova-S plus cards, with a focus on optimizing analog video input via Y/C (S-video) to minimize frequency roll-off. The resource also provides insights into data rates for HD (1080i) content, recommending 8 to 12 Mb/s for optimal performance. Software utilized includes _Ubuntu Studio 10.04_, WinFF, VLC, and TMPGEnc Editor, underscoring the project's reliance on open-source tools and a foundational understanding of LAN networks and DVB transport streams.

SAT filters ensure effective full-duplex satellite QSOs by mitigating interference between 145 MHz uplink and 435 MHz downlink signals. Custom coaxial and SMD-based filters address transmitter harmonic interference and improve receiver isolation, achieving over 70 dB suppression in the undesired band. Designed for simplicity, these filters maintain optimal VSWR and are housed in shielded brass enclosures. Practical implementations with Yagi antennas demonstrate compatibility with SDR systems, enabling seamless communication even in challenging satellite conditions, such as low-elevation passes and DX pile-ups.

FURUNO provides advanced marine communication systems for merchant, fishing, and recreational vessels, including radar, AIS, ECDIS, weather fax receivers and satellite equipment, enhancing safety and efficiency at sea.