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Homemade 40 through 6 meter HF portable multiband antenna, an aluminium antenna construction article, with plan, drawings and photos

The Pfeiffer Maltese Quad Antenna System presents a unique approach to traditional quad antennas by utilizing a linear loading technique. This method effectively reduces the overall size of the antenna while maintaining its performance capabilities. Designed by Andrew Pfeiffer, the antenna's configuration resembles a Maltese cross, which not only enhances its structural integrity but also allows it to withstand challenging environmental conditions. This system is adaptable, offering various configurations from a 4-spreader Maltese Quad to a 16-spreader Maltese Quadruple-Cross, making it suitable for operators looking to optimize their setup without sacrificing efficiency. This antenna system is particularly versatile, covering multiple bands including 40, 20, 17, 12, and 10 meters. The design focuses on minimizing the physical footprint while ensuring effective signal transmission and reception. Amateur radio operators can benefit from the detailed plans available in the accompanying PDF, which outlines the construction process and specifications. Whether you're a seasoned DXer or a newcomer to the hobby, the Pfeiffer Maltese Quad Antenna System offers a practical solution for enhancing your station's capabilities.

A G5RV plan for 10-160 meters, 10-40 and 10-80 meters band

A 40 meters band full wave antenna project plan with model, adding the Missing Leg to the Inverted-L Antenna

40 meters band Delta loop antenna plan that is vertically polarised

A double bazooka antenna plan for the cw portion of the 40 meter band

A delta loop wire antenna plan for the 7 MHz band (40 meters) that is quick to setup and work with

Three eh antenna plans for 20 40 meters bands.

The document discusses a two-element parasitic Delta-Loop array for the 40 meters band, aimed at radio amateurs interested in antenna projects. It provides detailed plans and instructions for building a homemade Delta-Loop antenna.

How to build a ground plane antenna for the 40 meters band in french

JJ0DRC's HF multi-band delta loop antenna project, initially conceived during the waning peak of Cycle 23, addresses the common challenge of achieving effective DX operation from a small residential lot in Japan. Dissatisfied with a ground plane antenna's performance in SSB pile-ups, the author sought a beam-like solution without a tower, drawing inspiration from a JJ1VKL article in CQ Ham Radio Sep. 2000. The antenna, constructed in October 2000, employs two 7.2-meter fishing rods (37% carbon fiber, reinforced with cyano-acrylate glue and aluminum tape) and 1mm enameled wire, fed by an Icom AH-4 external antenna tuner. While the exact beam pattern remains unmeasured, JJ0DRC observed a significantly higher callback rate compared to dipole antennas, particularly on higher bands. The system's circumference length of 15-20m is crucial for maintaining a good beam pattern across HF bands, though performance on lower bands like 80m, 40m, and 30m becomes less directional as the length deviates from a full wavelength. Ongoing maintenance addressed degradation issues, including aluminum tape cracking and wire breakage at connection points due to strong winds (often exceeding 10-15m/s in winter). The author reinforced rod connections with IRECTOR PIPE SYSTEM components and INSU-ROCK ties, and improved wire attachment methods using Cremona rope and epoxy bond to enhance durability.

A project of a small antenna, just 50 cm for the 7 MHz band. An EH Antenna plan for the 40 meters band

This article compares two commercial vertical antennas for the 4-meter amateur radio band: the Watson WVB-70 half-wave and the Sirio CX4-71. The Watson measures 2.03m in length, costs around £40, and exhibited adequate performance but required additional waterproofing after rain affected its VSWR readings. The longer Sirio CX4-71 (3.02m) performed noticeably better, delivering signals approximately 2 S-points stronger than the Watson. The Sirio demonstrated high build quality, a stable 1.2-1.4:1 VSWR, and weather resilience, though minor VSWR fluctuations were observed during rain and frost. Both antennas are half-wave designs requiring no ground plane radials.

The page discusses the concept of a 2-element Parasitic Ground Plane antenna for the 40-meter band. It includes a conversation between amateur radio operators discussing modeling results and design considerations for the antenna. The author shares insights on radial configurations and the impact on antenna efficiency and pattern.

The Buddipole Deluxe, a portable HF/VHF antenna system, receives a practical assessment from IW5EDI after a month of field use. The author, constrained by antenna restrictions, highlights the system's crucial role in enabling portable operations, even managing sporadic digital activity from a balcony. Direct comparisons to a fixed 3-band dipole reveal surprisingly comparable signal reports on 15, 17, and 20 meters, underscoring the Buddipole's effectiveness in real-world scenarios. Tuning the Buddipole proves straightforward on bands down to 20 meters, though the review notes significant challenges with SWR on lower bands like 40 meters, where achieving better than 3:1 SWR was problematic. Observations also include SWR variations with dipole rotation and mast height, suggesting environmental factors play a role. The overall manufacturing quality of the antenna and its accessories, including the tripod and carry bag, is deemed good, despite a minor issue with a pole connector. Looking ahead, the author plans to construct a homemade Buddipole version, possibly optimized for the 30-meter band, specifically for PSK31 operations from an apartment. This personal project reflects a common amateur radio practice of adapting commercial designs for specific needs, further extending the utility of portable antenna concepts.

The 2200-meter band (135.7-137.8 kHz) presents unique challenges for amateur radio operators due to its narrow 2.1 kHz bandwidth, low signal levels, and high noise. W1TAG explores various transmission modes suited for this demanding environment, highlighting that traditional voice modes like SSB and AM are impractical. Plain old CW serves as the baseline, demonstrating effectiveness across different modes, though signal-to-noise ratio (SNR) significantly limits practical speeds. The article notes that reducing CW speed below 5 WPM can improve copy, especially with computer-aided spectrum analysis software capable of decoding signals too weak for human ear reception. QRSS, or "CW sent slowly enough that speeds are best expressed in seconds per dot," is a key mode for LF work, with examples ranging from 3 seconds/dot to extreme 240 seconds/dot transmissions. _Argo_ by I2PHD is mentioned as a simple program for QRSS, enabling reception of signals like BRO, a Part 15 beacon, at a distance of **1100 miles**. Other modes discussed include Dual Frequency CW (DFCW), which uses frequency shifts to distinguish dots and dashes, and Binary Phase Shift Keying (BPSK), a phase modulation technique employing 0 to 180-degree phase flips. WOLF (Weak-signal Operation on Low Frequency), a specialized BPSK form by KK7KA, encodes 15-character messages into 960-bit packages, taking 96 seconds to transmit, and has demonstrated successful reception over **672 seconds** for a message from a 1-watt beacon. Further modes include PSK, FSK variations like JASON and MSK, and graphical modes such as Hellschreiber and Chirped Hell. The article concludes with a practical chart comparing the time required to send a simple message like "WD2XES FN42CH " across these diverse LF modes, offering valuable insights for operators planning contacts on the low bands.

The Boone Area Radio Klub (BARK) serves Boone County, Iowa, as its local amateur radio club, actively welcoming visitors to its meetings and weekly ARES nets. The club maintains a 2-meter repeater on 146.850/250 MHz with a 114.8 Hz tone and a 440 MHz repeater on 443.9+ MHz, both situated at the Boone County Hospital, with a simplex fallback on 146.550 MHz for the 2-meter net. Additionally, BARK supports the Iowa 160-meter ARES net at 1.972.5 MHz, which operates at 9:30 PM on Sundays, featuring a rotating schedule of net controls including KNØR, KBØMPL, NØISU, KEØQEU, and KBØLPI. BARK conducts bimonthly license testing sessions on the second Saturday of even-numbered months, with specific dates like October 19, 2024, at the Hamboree, requiring a $15 fee and prior FCC Registration Number (FRN) acquisition. The club's activities are well-documented through numerous photo galleries from past Field Days (1998, 1999, 2008, 2010, 2013, 2017, 2018, 2019), JOTA events (2013), and special event stations (2010 B&SVRR&M). Members like KBØMPL (Margot Conard) have contributed educational PowerPoint presentations on topics such as "Fun with Handie Talkies," "HF Propagation," and "Digital Mode - FLDIGI - OLIVIA 8/500 - JT65 HF - BAND PLANS." The club's officers, as of May 2018, include WØFS (Clay Conard) as President, NØISU (Mitch Carroll) as Vice-President, and KBØLPI (Eric Sloan) as Treasurer/Secretary, guiding the club's operations and community engagement.

The PG7V Contest Calendar provides a curated listing of significant **HF contests**, with a particular focus on events relevant to European amateur radio operators. It details contest specifics such as start and end times in UTC, eligible bands (e.g., 80 meters, 40 meters, 10 meters), and required exchange information (e.g., serial number, CQ-zone, DOK, locator, age). The calendar includes diverse modes like CW, SSB, PSK63, RTTY, and FT4, catering to various operating preferences. Featured contests include the RSGB 80m Club Championship, WW WPX Contest, IARU Region 1 Fieldday, and ARRL International Digital Contest. Each entry links directly to the official contest rules for detailed information. The calendar also notes specific participation rules, such as the 1 KHz QSY requirement in the HA3NS Memorial Contest or the 24-hour single-operator time limit in the ARRL International Digital Contest. This resource is updated regularly, ensuring timely information for upcoming **contest operations** over a four-week period. It serves as a practical tool for hams planning their contest activity.

This article explains the trick of how to shorten and lengthen pairs of radials to make a 2-band ground plane antenna. Included is a "Table of Multi-Band Possibilities" covering the range of 6 to 40 meters.