hf radio

hf radio

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• 70Mhz (4 metre) Delta Loop Antenna - Discover the success story of creating a 4-meter Delta Loop antenna, ideal for improving radio communication. This horizontally polarized antenna offers efficient performance when mounted at VHF heights, catering to both HF and VHF characteristics. A simple, DIY project suitable for portable setups, providing versatile options for radio enthusiasts.
  [ Hits: 53 | Votes: 1 | Rating: 4 ]

• Moxon Mania - Building the Ultimate 4-Band Moxon Antenna - The article details the design and construction of a four-band Moxon beam by a radio amateur. The beam, mounted atop a rooftop tower, aimed for gain over a dipole on 20 meters, cost under $500, and included additional bands. The design features fiberglass spreaders, four bands (20/15/10/6 meters), and a single feedpoint. The construction involved computer modeling, NEC source code, and specific dimensions. The article outlines the assembly, materials, and tuning process, including in-situ adjustments for optimal performance. Despite initial challenges, the beam improved signal strength and facilitated contacts on multiple bands, marking it as the best HF antenna the author has owned.
  [ Hits: 96 | Votes: 0 | Rating: 0 ]

• UHF VHF Crossed Satellite Yagi Antenna - This home made antenna provides around 10.5dBd gain on 70cm, and 6.5dBd gain on 2m, which is more than adequate to work the FM satellites with a handheld dual band radio
  [ Hits: 380 | Votes: 2 | Rating: 9 ]

• Ribbit digital text messaging mode for HF/VHF/UHF - Ribbit is a novel digital text messaging mode for VHF/UHF communications for recreational and emergency use which radically increases the density of information transmitted by spectrum used. It leverages the computing power of the modern smartphone to increase the capabilities of any Handy Talkie without requiring any additional hardware or cable. A Ribbit message is fixed in duration at 1250 milliseconds. It is sent over audio modulation with a 2kHz bandwidth centered on 1.5kHz. It is preceded by 400ms of white noise to open analog squelch circuits.
  [ Hits: 133 | Votes: 1 | Rating: 10 ]

• A Magic Ground Mobile Antenna - Experimenting and testing vertical antenna for HF bands on mobile operations.
  [ Hits: 113 | Votes: 0 | Rating: 0 ]

• Introduction to HF Packeteering in the Modern Age - A brief overview of the current state of packet radio on the HF bands. In this comprehensive guide, the author navigates through HF packet radio, providing insights on the required equipment, protocols like Fx.25 and IL2P, and preferred ACDS segments. The post covers decoding and sending traffic, delving into optimal settings, recommended software, and common SSIDs. The author concludes by encouraging further exploration through additional reading and a Linux Packeteering series.
  [ Hits: 80 | Votes: 0 | Rating: 0 ]

• FunCube Dongle HF Upconverter: Expanding Reception Range - This article describes an HF upconverter for the FunCube Dongle Pro. Designed for radio amateurs, the converter extends reception capabilities to lower frequencies (0 Hz to 30 MHz) by mixing them with a higher oscillator frequency (100 MHz). This translates the desired signal into a range detectable by the FunCube Dongle (64 to 1,700 MHz). Key components include a double-balanced mixer and a low-pass filter to suppress unwanted signals. The project provides schematics, filter specifications, and design considerations for construction.
  [ Hits: 34 | Votes: 1 | Rating: 8 ]

• 40 MHz 8m Band Amateur Radio Exploration - The 8m ISM band, a unique frequency range between 10m and 6m, holds potential for amateur radio enthusiasts, yet it remains largely unallocated. This spectrum offers fertile ground for research and self-training. The author's experience with low-power transmissions and WSPR testing highlights the band's capabilities and the need for a narrow, speech-free amateur allocation to encourage experimentation. Discover the world of 8m ISM radio exploration and its future possibilities.
  [ Hits: 74 | Votes: 1 | Rating: 8 ]

• Exploring the Spectrum From HF to UHF Frequencies - During radio's early days, high frequencies were under 30 MHz due to technical limitations. As understanding grew, components improved, allowing for higher frequencies like VHF and UHF up to 3 GHz. The HF band's long wavelengths provide unique propagation challenges influenced by solar activity. VHF and UHF bands face diffraction and reflection issues but offer diverse applications, from amateur radio to 5G and GPS technologies.
  [ Hits: 77 | Votes: 0 | Rating: 0 ]
• Mastering HF Communication: Decoding Space Weather Data - The article enlightens radio amateurs on utilizing real-time space weather data to optimize HF communication. Navigating through Hp30 index, MUF, f0F2, and eSFI metrics, it explains their significance in band selection and propagation forecasting. With essential links and practical insights, enthusiasts learn to discern optimal conditions for high-band DX, low-band DX, and NVIS operations. The author's observations and antenna optimization tips enrich understanding for effective HF operations.
  [ Hits: 68 | Votes: 0 | Rating: 0 ]

• HF Radio Propagation Forecast  ^updated - This page offers radio amateurs (experienced and beginners) a useful overview and tutorials on HF propagation conditions. Here you will find basic and advanced explanations, as well as practical methods, charts, maps, models, real-time measurements, assessments, comparisons, references, and an index.
  [ Hits: 359 | Votes: 19 | Rating: 8.79 ]

• Elecraft K4 Transceiver - Official Elecraft K4 Transceiver page at Elecraft web site with technical specifications, news, manuals and software updates for the K4, HF High performance direct sampling SDR Radio transceiver by Elecraft
  [ Hits: 71 | Votes: 0 | Rating: 0 ]

• Yaesu FT-818 Review - An owner point of view of the Yaesu FT-818 QRP transceiver capable to work HF VHF UHF in CW, AM, LSB, USB, FM, PACKET.
  [ Hits: 34 | Votes: 1 | Rating: 9 ]

• SWLog - Shortwave and Amateur Radio Log (SWLog) is a modern suite of applications that provide logging and remote control for amateur radio and shortwave, utility, and broadcast listening. SWLog has been continuously improved and expanded since it was first released in 1988. SWLog is a suite of products that provides logging, radio control, GPS synchronization, QSL management, reporting, and propagation prediction. Program schedules from HFCC, ILGRadio, AOKI, ADDX, SWSkeds, EiBi, and others are leveraged for broadcast reception. Call sign lookups and remote logbooks are integrated with ClubLog, eQSL, QRZ, Ham365, HamQTH, and LoTW. SWLog provides Android and iOS applications for logging on the go as well as web servers for logging and remote control from anywhere. SWLog works on Windows, Linux, iOS and Android
  [ Hits: 111 | Votes: 0 | Rating: 0 ]

• Simple Ham Radio Remote - SimpleHRR is a free ham radio remote control web application (or web app) hosted by Raspberry Pi in the ham station to remote control a ham radio HF transceiver through a supported web browser from a Desktop PC, Laptop or Android phone. Supports recent ICOM IC-7x series transceivers
  [ Hits: 182 | Votes: 2 | Rating: 10 ]

• VARAc - VarAC is a FREE, modern HF P2P real-time chatting application for the amateur radio operator that leverages the glorious VARA protocol
  [ Hits: 103 | Votes: 1 | Rating: 10 ]

• Building a Robust PL519 Tube HF Amplifier - his article explores the construction of a PL519 tube amplifier, utilizing Ulrich L. Rohde N1UL's insights. Focusing on a modest 25W continuous output, the design ensures robustness with forced air cooling. The detailed breakdown covers input matching, screen grid voltage generation, bias adjustment, anode power supply, heater power supply, and monitoring circuitry, providing valuable guidance for ham radio enthusiasts.
  [ Hits: 71 | Votes: 0 | Rating: 0 ]

• DIY EMC/RFI Mains Filter for a Clean Shack - Utilizing snap-on ferrite cores and practical insights, the author enhances their shack's cleanliness against electromagnetic interference. With meticulous experimentation and installation, they improve noise levels across HF bands, reflecting on the effectiveness of their filter in minimizing common-mode disturbances. Updates underscore ongoing refinement and cautionary advice for optimal filtering and radio reception amid changing RF environments.
  [ Hits: 154 | Votes: 1 | Rating: 10 ]

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