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Drawings pictures and notes on a rotary dipole antenna for 30 and 40 meters band

Demonstrates the product line of _LZ Antenna Ltd._, a Bulgarian manufacturer specializing in amateur radio antennas and custom electronic devices. The company focuses on robust, high-quality HF multiband Yagi and vertical antennas, leveraging over 20 years of experience from founder Georgi Georgiev in radio amateur development. Featured models include the LZA 8-4, LZA-10-3, and the LZA-7-3A WRTC 2022, alongside various rotary dipoles like the LZA1 40/30m. Provides specifications for several Yagi antennas, such as the LZA-9-5, LZA-13-7, and LZA-6-3 (a 6-element, 3-band design). The company emphasizes applying "leading edge technology" to high-frequency communication equipment production, with products designed for durability and performance. The LZA-10-5 Yagi offers **12.5 dBi** gain on 10m, while the LZA-13-7 provides **13.2 dBi** on 20m, showcasing competitive gain figures for DXing and contesting.

Presents a construction project for a linear-loaded 40-meter rotatable dipole, detailing the design evolution from mid-element coils to 300-ohm twinlead loading. It covers material selection, including repurposed fishing poles and EMT conduit, and outlines the assembly process for the antenna elements and mounting plate. The resource provides specific measurements for element lengths and linear loading sections, along with SWR plots demonstrating the antenna's resonance at 7.035 MHz with a 1.1:1 SWR, and bandwidth up to 7.120 MHz below 2:1 SWR. The article documents the antenna's performance during various RTTY and CW contests, including the SARTG RTTY and SCC RTTY contests in August 2006, and the ARRL DX CW and CQWW WPX RTTY contests in February 2007. It reports successful operation at 500-1000W, noting improved performance after replacing a faulty coax cable. Specific DX contacts from British Columbia, including stations in Europe and South Africa, are listed, illustrating the antenna's capability despite its shortened length and relatively low height of 55 feet. The content highlights practical considerations such as weatherproofing the connections and supporting the fiberglass elements to prevent sagging. It also includes a brief comparison to an inverted-V at similar height and a ground-mounted vertical, noting the rotatable dipole's quieter reception. The author shares insights into the iterative design process and tuning adjustments made to achieve optimal resonance.

Presents DJ5IL's personal amateur radio station, detailing his journey as a licensed operator since 1973. The resource covers his **shack setup**, including an Elecraft K4D, Icom IC-7610, and various vintage transceivers like the Drake 2-B, along with a SPE Expert 1K-FA amplifier. Antenna systems include a PRO.SIS.TEL RD1524T rotary dipole for 40/20/15/10m at 15m height, an 18m vertical dipole with an SGC SG-230 tuner for 3.5-30 MHz, and an inverted-V dipole for 80m. The site features a **QSL gallery** showcasing his custom card designs and outlines his QSL policy, emphasizing the exchange of unique, personalized cards over generic confirmations. It also includes a detailed operator's biography, tracing his early fascination with radio, obtaining his license at 16, and memorable QSOs, such as a contact with his blood-relative W3NZ. The resource also delves into the historical significance of amateur radio's role in pioneering shortwave communication following the 1912 International Radiotelegraph Convention, which initially relegated amateurs to wavelengths of 200 meters and shorter. DJ5IL's philosophy on "ham spirit" is discussed, stressing the unpolitical nature of amateur radio as a global fraternity.