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• 20 meter short loaded vertical antennas - Loading is a way to lower the resonant frequency of an antenna radiator. This technique is typically used in antennas that have radiating elements that are too short for the desired resonance frequency. In this excellent article the author experiment loaded vertical dipoles for 20 meters band
  [ Hits: 232 | Votes: 1 | Rating: 9 ]

• Half-Length Dipoles for 40 Meters - Complete collection of the four main parts of this excellet research on modelling and designing half wave dipole antennas for 40 meters band, covering all aspects beginning from full wave length antennas, to shortened, loaded and reshaped dipoles
  [ Hits: 382 | Votes: 2 | Rating: 10 ]

• About The Beverage Antennas - Receiving Antennas - An article about the Beverage antennas, super long wire receiving antennas thar are unidirectional and have a very low noise that makes this antenna excellent for low band dxing. By Thomas R. Sundstrom W2XQ, 73, June 1981, 73 Magazine
  [ Hits: 185 | Votes: 1 | Rating: 10 ]
• A Reversible Beverage at ZL3IX  ^updated - How do two-wire reversible direction Beverages work, an excellent document that explains fundamentals of beverage antennas. This article details the design and performance of a reversible beverage antenna. Leveraging orthogonality between common mode and differential mode currents on a 2-wire line, this antenna facilitates independent reception from both ends. While common mode signals arrive and are summed on a transformer's secondary for common mode reception, differential mode signals induce anti-phase currents, providing individual reception. Various measurements explore impedance, transmission loss, and F/B ratio, highlighting the antenna's effectiveness and areas for improvement. Notably, increasing the antenna's height significantly improved performance.
  [ Hits: 519 | Votes: 0 | Rating: 0 ]

• Helical Antennas for 144 MHz - This article is about two excellent small helical antennas for the two meters band. With performance close to that of full sized antennas, these small helical antennas are low in profile but high in efficiency.
  [ Hits: 230 | Votes: 1 | Rating: 7 ]

• Small Loop Antenna for the 80m to 10m - This article describes the development of two tunable antennas each consisting of three interconnected small loops and capable of providing excellent DX performance. The aerials are home-constructed, and located in a very small garden with a minimum of visual impact on the neighbours and are low enough in height to avoid the attention of UK planning authorities.
  [ Hits: 403 | Votes: 1 | Rating: 8 ]

• Magnetic Loop for 20 meters band - A magnetic loop antenna designed for 14 MHz. This kind of antennas is also known as STL, small transmitting loop and can be an excellent solution when you are not allowed to put antennas on your roof
  [ Hits: 204 | Votes: 0 | Rating: 0 ]

• The Off-Center-Fed Dipole Antenna - The OCFD Off-Center-Fed Dipole Antenna is an excellent multiband antenna that is relatively simple to construct, yet gets quite decent performance.
  [ Hits: 328 | Votes: 2 | Rating: 9 ]

• Learning Morse Code by the Koch Method - Learning CW using the SuperMorse Software Package, an excellent tool for implementing the Koch Method of learning Morse Code. Configuring the software, learning all characters, tips and tricks on choosing the right order.
  [ Hits: 130 | Votes: 0 | Rating: 0 ]

• The KA7OEI FT-817 Battery Types - Operating the FT-817 from various types of batteries, such as Alkaline Cells, NiCd or NiMH rechargeable batteries. An useful article that compares usage of different types of batteries for the Yaesu FT-817
  [ Hits: 95 | Votes: 0 | Rating: 0 ]
• FT-817 Batteries for Air Travel - Three cell Lipo batteries for the FT-817 work really well, although not really sure about taking them on aircraft. The Lipos intended for use on RC Electric airplanes generally have a very low internal resistance and no internal protection against short circuit.
  [ Hits: 140 | Votes: 0 | Rating: 0 ]

• Challenger DX Antenna Review by NK7Z - A review of the GAP Challenger DX Antenna that is not a traditional 1/4 wave vertical, but is a vertical dipole, this gives it several advantages over a standard 1/4 wave vertical, mainly the reduced number of radials, with excellent performances.
  [ Hits: 221 | Votes: 2 | Rating: 10 ]

• Icom IC-R8600 Review - Review of the excellent ICOM IC-R8600 Wide Band SDR communications receiver. Featuring Direct Sampling SDR below 30 MHz Hybrid Superhet / SDR above 30 MHz.
  [ Hits: 140 | Votes: 1 | Rating: 10 ]

• ZenitPCB - An excellent tool to create, design printed circuit boards in a simple and easy to learn way. ZenitPCB is free for personal and amateur use, limited to 1000 pins, that is more than enought for any amateur radio electronic project
  [ Hits: 142 | Votes: 1 | Rating: 8 ]

• 3D Printed Accessories for the FT-817 and KX2 - DC plug adaptor using an XT60 connector. 18650 Lithium battery 3 cell carrier, Three band end fed half wave antenna, XT60 chassis mounted flange.
  [ Hits: 185 | Votes: 0 | Rating: 0 ]

• 100 Watt RF Power Amplifier for 2 GHz - Modification to an old cellular phone base station modules, with a fairly reduced output power (10 watts or so), the stock power amplifier modules will cover the 2.3 GHz and 2.4 GHz amateur radio bands.
  [ Hits: 160 | Votes: 0 | Rating: 0 ]

• 50Ah LiFePO4 battery - A LiFePO4 battery box build project made with 25Ah 3.2V LiFePO4 prismatic cells, 40A 4s1p BMS with Bluetooth, 10A Buck/Boost converter
  [ Hits: 111 | Votes: 1 | Rating: 10 ]

• N-Type Connector on Cellflex Cable - Installation of Female N-Type Connector on 1-5/8 RFS Cellflex Cable
  [ Hits: 96 | Votes: 2 | Rating: 6.5 ]

• Home Made Artificial Ground Tuner - Home made Artificial Ground. This article contains a schematics of a custom artificial ground device that can be used to ground your station equipment if you live in an higher floor and cannot effort a proper dedicated ground connection. This Artificial Ground has been designed by Colyn Baillie-Searle GD4EIRP
  [ Hits: 587 | Votes: 0 | Rating: 0 ]

• The G4AON SSB Transmitter - This transmitter covers the 160, 80, 40 and 20 metre bands and provides both SSB and properly generated CW. The CW side of this transmitter is not compromised and produces excellent CW. On SSB the audio has been tailored to provide a rising response to 3 KHz, with a sharp drop above that frequency. There is RF speech clipping to both provide more "punch" and to limit the peak output.
  [ Hits: 181 | Votes: 2 | Rating: 9.5 ]

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