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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.

Monitoring Times, SWL, BCL, montly reports, Broadcast band, satellite television, long-wave coverage, Reviews of new products and radio-related software.

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.

The page, focuses on **TVRO** (Television Receive-Only) satellite systems, specifically addressing C-band and Ku-band reception. It covers technical aspects of digital video broadcasting, including **DVB** and MPEG-2 standards, relevant to satellite television enthusiasts. Content includes discussions on Digicipher 2 and 4DTV systems, which were prominent in North American satellite television at the time. The resource also references the South Scanner Satellite Services Chart (SSSSSC), a tool for identifying satellite transponders. While primarily about commercial satellite TV, the underlying principles of satellite signal reception and digital modulation have tangential relevance to amateur radio satellite operations.

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.

SDR Television v1.0 operates as a DVB-S2 / AAC / H264 / H265 program, specifically engineered for QO-100 satellite Digital Amateur Television (DATV) operations. It provides a full-duplex solution on modern x86 computers running Windows 10 or 11 (64-bit, 8+ cores, AVX2 support recommended), leveraging DLLs from _SDR Console_ for control of devices like _Pluto_ and _LibreSDR.TV_. The software requires installation of the SDR Radio kit for wideband mode support. Initial development focused on a proof-of-concept for QO-100, with future enhancements planned to include H266 / AV1 / Opus codecs and an improved cross-band user interface. The current stable release functions reliably for QO-100 DATV. Users must install the SDR Radio kit, followed by the SDR Television kit, into the same directory. Support inquiries are handled via the SDR-Radio.com mailing list, ensuring direct assistance for operational questions.

Receiving Digital Amateur Television (DATV) signals requires specialized software to interface with hardware tuners and decode the video stream. The _MiniTioune_ software, developed by F6DZP, serves this purpose, providing a Windows-based application for DVB-S and DVB-S2 reception and analysis. It is designed to work in conjunction with _MiniTiouner_ hardware, enabling hams to monitor DATV transmissions, including those from the QO-100 geostationary satellite. The resource outlines the initial setup process, including connecting the MiniTiouner hardware via a high-quality USB2 mini cable and running diagnostic test software. It details how to configure essential parameters such as symbol rate (SR), FEC rate, and DVB mode for various signal sources, from domestic satellite dishes to local DATV transmitters. Troubleshooting steps for common issues like "no video displayed" are also provided, often pointing to corrupted software filters or incorrect _Auto PID_ settings. Advanced features like the Web monitor for remote signal reporting and integration with _VLC_ media player for more tolerant decoding of non-DVB compliant signals are covered. The document also references a comprehensive user guide by W6HHC for the _MiniTiouner-Express_ system, which utilizes the same software, offering further in-depth assistance for operators.