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• Build a Lightweight 15m Yagi Antenna: Simple Design for Impressive Performance - In this article, Steve G0UIH presents a straightforward guide for constructing a lightweight 15m 3 Element Yagi antenna with impressive performance metrics. With a focus on ease of construction and efficiency, the design boasts a nearly 8.2dbi forward gain and 30db front to back ratio. Utilizing readily available materials and a hairpin match for impedance matching, this Yagi offers broad bandwidth and simple tuning for optimal operation across the 15m band.
  [ Hits: 71 | Votes: 0 | Rating: 0 ]

• Budget-Friendly 5-Element Quad Antenna Design - Constructing a 5-element quad antenna, the author aimed for low cost and simplicity, resulting in an effective design with 11 dBi gain and SWR of 2:1 or better across the 2-meter band. Using wood and dowels, the antenna costs under $8 and takes less than two hours to build with basic tools. The model predicts excellent performance, confirmed by ARRL Lab measurements. Practical field results demonstrate improved communication, even in simplex mode.
  [ Hits: 118 | Votes: 1 | Rating: 7 ]

• Full size 80m End Fed Half Wave Antenna - The author reflects on expanding their antenna for 80m coverage during lockdown. They extend the End Fed Half Wave (EFHW) using a Spiderbeam pole and "cheating" by dog-legging across their garden. Despite challenges, they achieve coverage for multiple bands with minimal cost. Practical Wireless features EFHW antennas, including a pre-made 20m EFHW extended for 40m.
  [ Hits: 94 | Votes: 0 | Rating: 0 ]

• Do not wind chokes on red toroids! - I happened to stumble across some antenna projects showing common mode chokes 1:1 baluns made of some turns of coax wound on T200-2 iron powder toroids.
  [ Hits: 187 | Votes: 0 | Rating: 0 ]

• Magnetic Loop 600 KHz-4MHz - The antenna is built on a cross-shaped frame with spar width (and height) of 48 inches, providing a height of 52 inches and a width of 49 inches. This antenna costs only about $45 to construct and can be built in just a few hours using simple hand tools. The best part is that the performance on 160M and 80M is excellent
  [ Hits: 173 | Votes: 3 | Rating: 4.33 ]

• Homebrew an OCF Off-Center Fed Dipole Antenna - This type of antenna is a popular antenna design as the performance is very good across the HF bands and requires little or no tuning. It’s a dipole fed off center with a 4:1 balun at the offset feed point. The antenna shown covers 80, 40, 20 and 10 meters. The formula can also be used to adjust the overall length to cover more or fewer bands and the resulting overall length. 160-10m, 80-10m or 40-10 meters depending on your available space. Other bands will require a tuner.
  [ Hits: 198 | Votes: 3 | Rating: 6.67 ]

• Efficient 2-Element Quad Antenna for 2m - A detailed guide presents a simple 2-element quad antenna for 2m, offering ease of construction, portability, and efficient performance across the 144-148 MHz band. The design allows quick disassembly for storage and features adjustable polarization, making it ideal for various applications, including transmitter hunting and SSB operations.
  [ Hits: 62 | Votes: 0 | Rating: 0 ]

• Satellite Yagi crossed 2m, 70cm - Construction of an antenna for experimental satellite communication, 8el. (435 Mhz) x 4el. (145 Mhz) Satellite Yagi crossed. No difficulty to built this antenna. Except the gamma match. that requires a little more attention
  [ Hits: 148 | 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 ]

• Mapping the Australian Radio Landscape - Discover a comprehensive solution for mapping Australian ham radio entities using data from the ACMA Public Register. This tool, developed in Delphi 7, generates KML files for Google Earth, showcasing repeaters, beacons, and operators across different prefixes. While respecting privacy regulations, the files provide valuable insights into the amateur radio landscape.
  [ Hits: 52 | Votes: 0 | Rating: 0 ]

• Building Your HF Packet BBS: Linux Packeteering - The guide details setting up a comprehensive HF packet BBS using linBPQ on a Raspberry Pi. Exploring linBPQ's versatility and community support, the author emphasizes its legality considerations and cross-platform accessibility. Configuration files for linBPQ, including bpq32.cfg, chatconfig.cfg, and linmail.cfg, are explained along with the systemd service setup. The linBPQ Web Management Interface and future setup for QtTermTCP are also discussed for a complete packet BBS experience.
  [ Hits: 41 | Votes: 0 | Rating: 0 ]

• Hamstick Experimentation: A Day of Surprising Results - In his POTA activation, WK4DS experimented with radials for hamstick antennas. Despite sun and RF noise challenges, successful connections were made. Surprisingly, tuned radials proved unnecessary, simplifying setup. Hamsticks demonstrated versatility across frequencies. Increased power improved signal quality, sparking his curiosity for further exploration in radio technology.
  [ Hits: 44 | Votes: 0 | Rating: 0 ]

• Receiving NOAA Weather Satellite Images - Receiving NOAA weather satellite images using a Raspberry PI with a RTL dongle and a Turnstile crossed dipole automatically.
  [ Hits: 112 | Votes: 0 | Rating: 0 ]

• MSF radio time signal - The MSF radio signal is a dedicated standard-frequency and time broadcast that provides an accurate and reliable source of UK civil time. It is available 24 hours a day across the whole of the UK and beyond. The signal operates on a frequency of 60 kHz and carries a time and date code that can be received and decoded by a wide range of readily-available radio-controlled clocks.
  [ Hits: 50 | Votes: 1 | Rating: 10 ]

• DIY 1KW Dummy Load - F5NPV explores the construction of a cost-effective 1KW dummy load for radio enthusiasts. Purchasing a commercial dummy load can be expensive, but with basic materials such as a metal can, resistors, mineral oil, and a heat dissipator, you can build your own. The article provides a simple guide to assembling the load, including the importance of testing for inductance. The DIY dummy load yields impressive performance, with an SWR of 1.2:1 across multiple bands and the ability to handle up to 1KW of power. This budget-friendly solution is a valuable addition to any radio shack.
  [ Hits: 121 | Votes: 0 | Rating: 0 ]

• Enhancing Frontend Performance with Optimized Band Pass Filters - This article explores the nuanced design challenges of Band Pass Filters (BPF) in radio receivers, balancing low insertion loss, high stop band rejection, and narrow bandwidth. The focus is on the "Series-Trap, Shunt-C" topology, resonator count impact, and meticulous layout design for superior stop band performance across various frequency bands
  [ Hits: 82 | Votes: 0 | Rating: 0 ]

• Prevention and Suppression of RF Interference to Audio Systems - In this study, the author builds upon Muncy's research, demonstrating that radio-frequency current on cable shields affects audio systems through the "pin 1 problem" and shield-current-induced noise (SCIN). An enhanced equivalent circuit for ferrite chokes is proposed, addressing dimensional resonance and inductor self-resonance. Field tests confirm that chokes reduce interference across 500 kHz to 1,000 MHz. Guidelines for diagnosing and mitigating EMI from various sources are provided for product development and field installations.
  [ Hits: 47 | Votes: 0 | Rating: 0 ]

• DIY EMC/RFI Mains Filter for a Clean Shack  ^updated - 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: 2 | Rating: 9.5 ]

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