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Details the construction of a J-vertical antenna specifically for the 10-meter band, offering a practical alternative to a _Slim Jim_ design for 28 MHz. The resource outlines the use of aluminum tubing for the half-wave vertical section and coaxial cable for the quarter-wave matching section, providing specific calculations for element lengths based on frequency and coaxial cable velocity factor. It contrasts the performance of the J-vertical with center-fed dipoles and end-fed verticals, noting superior results in previous comparisons. The article further presents a more recent iteration of the J-vertical, constructed using a fiberglass pole and insulated wire, with updated dimensions for 28.8 MHz. It includes practical advice on weatherproofing connections and securing the antenna for durability against adverse conditions, referencing the survival of an original _J Vertical_ during 110 MPH winds in 1987. The SWR performance is reported as 1.1:1 at 28.6 MHz, maintaining below 1.5:1 across 28.3 to 29 MHz.

To connect up your FT-817/857/897 to a PC you have a number of options. For the serial connection you can go ahead and obtain a CT-62 from YAESU. Alternatively you can make up your box with a level converter and cable using schematic in this page

LEMO, established in 1946, specializes in high-performance interconnect solutions, offering an extensive range of over 50,000 circular connectors. Their product line includes the REDEL SP IP68 series, which features resin-free IP68 sealing for robust performance without complex potting processes. These connectors are critical for applications in medical, military, test and measurement, security, defense, and industrial sectors, ensuring reliable signal integrity in harsh conditions. The company designs, tests, and manufactures high-quality cable solutions, providing complete connectivity services such as custom cable assembly and signal integrity analysis. LEMO's solutions are integral to advanced scientific endeavors, as demonstrated by their use in CERN’s NA62 experiment for instrumentation and maintenance. LEMO's 80-year history, detailed in their anniversary publication, highlights their evolution from a Swiss family workshop to a global leader in connector technology. Their product finder tool assists customers in selecting appropriate connectors from their broad portfolio, which also serves audio-video, transportation, aerospace, and UAV applications.

This article describes the construction of a simple dual-band VHF/UHF end-fed vertical dipole antenna designed for local repeater access using an Icom IC-705 radio. Built from a single piece of RG58U coaxial cable, the antenna consists of a 460mm exposed inner conductor, 450mm of intact coax, and a 9-turn choke balun wound on a 27mm former. Mounted on a 10m Spiderpole, the antenna achieves excellent SWR readings (<1.2:1 on 2m, <1.5:1 on 70cm) and provides effective coverage of local repeaters with unexpected reach into distant locations.