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Constructing a **J-Pole antenna** from 450 Ohm ladder line for 2-meter (144 MHz) and 70-centimeter (440 MHz) operation involves specific calculations and assembly steps. The design, based on an earlier KD6GLF concept using 300 Ohm twinlead, features a ¾ wavelength radiator and a ¼ wavelength matching stub, functioning as an end-fed half-wave antenna without requiring ground radials. It offers a gain of 2.4 dB over isotropic. The resource provides the formulas for determining the lengths of the ¾ wave radiator and ¼ wave stub, incorporating a velocity factor of 91% for 450 Ohm ladder line. For 146 MHz, the radiator measures 55 3/16 inches and the stub 18 3/8 inches. Construction details include cutting a 57¾-inch piece of ladder line, stripping 4 inches from one end, and attaching a 24-inch section of RG58 or RG8X coax with a 3-5 turn RF choke. SWR adjustment is achieved by sliding a shorting bar or by incrementally trimming the elements at a 1:3 ratio (stub to radiator). The goal is a 1:1.1 SWR at 146 MHz, which typically yields 1:1.2 at 446 MHz. The article also discusses power handling, noting that while 10-15 watts is fine, 50 watts may increase SWR to 1:2.1, and advises keeping the antenna away from other objects to prevent coupling and SWR degradation.

The Spartan Sprint Special 40m CW Transceiver, originally documented in 2002 and reproduced in 2019, details a **QRP** direct conversion rig designed for portable operation. This project evolved from an experimental CMOS digital IC receiver, which proved too noisy for weak signals, into a dedicated 40-meter CW transceiver. The author, VE3SMA, aimed for reduced size, lower weight, and decreased receive current drain compared to earlier iterations, drawing on his extensive contesting experience and even his time operating million-watt transmitters at Radio Canada International. This compact transceiver delivers approximately 200 mW output, VFO-tunable over 15 kHz within the 40m band, and weighs a mere 73 grams (0.16 lb) including its balsa wood case. It features fast semi-break-in and sidetone, with a receive current draw of about 14 mA (no signal) and transmit current draw around 125 mA key down. The design incorporates various construction techniques, including knife-cut surface mount boards and through-hole components, often salvaged from junked cordless phones and cellphones. Despite its direct conversion architecture, which offers usable but not superheterodyne-level selectivity, the rig proved effective, achieving a fourth-place finish in a June 2001 Spartan Sprint contest when paired with a 26-foot vertical antenna. The article provides comprehensive circuit details, including an unconventional VFO using a high-speed CMOS inverter chip and a balanced mixer utilizing a 74HC4053.

This resource presents a non-rigorous evaluation of the front-to-back (F/B) ratio of short Beverage antennas, specifically designed for low-band operation on frequencies such as 160, 80, 40, and 30 meters. The author, VE1ZAC, details the methodology used to measure the F/B ratio, which involves using a Millen Grid Dip Oscillator as a portable signal source. Measurements were taken by switching the antenna direction and recording S Meter and preamp readings to derive gain numbers. The document discusses the challenges faced in achieving accurate measurements and the assumptions made during the process, such as the calibration of S Meter units at 6 dB. This evaluation is particularly relevant for amateur radio operators interested in antenna performance on low bands.

eham reviews of the Kenwood TS-440S, and Kenwood TS-440S/AT, 160-10 Meter HF ham radio Transceiver/Auto Tune.

Presents the RI8KR RRA Island Hoppers DXpedition, detailing its schedule from August 21 to 28, 2026, and its objective to activate four new island groups in the Ob Bay of the Kara Sea. The expedition targets specific Russian River Club (RRC) references: RR-06-66 (Ob River Delta Islands West), RR-06-67 (Ob River Delta Islands North-West), RR-06-68 (Ob River Delta Islands North), and RR-06-69 (Ob River Delta Islands Center/North). Operators Vladimir, RK8A, and Igor, UA3EDQ, will operate on 40, 30, 20, 17, 15, 12, and 10-meter bands using CW, SSB, and potentially Digital modes. Three of these activations contribute to IOTA AS-109, an entity not activated since 2013. The page provides QSL information via RZ3EC (Eugene Shelkanovtsev, P.O. Box 70, Orel 302028) and online platforms including RRAWARD.RU, LoTW, RDAWARD.RU, and CFMRDA.RU. It lists supporters of the expedition, acknowledging contributions from various amateur radio operators. Recent updates confirm the purchase of airplane and boat tickets for the team's travel to Salekhard and Salemal/Panayevsk, indicating active preparation for the August 2026 operation.

Presents the NED International DX Group, a **CB radio** organization established in the Netherlands on August 23, 2026, by 19NED000 and 19NED001 Henricus. The group primarily operates on the **11-meter band**, utilizing various modes including FM, AM, LSB, USB, CW, FT8, FT4, FT2 Ross, and JS8, with all digital modes permitted. Membership is free and open to active operators and SWLs. Key operating frequencies include 27.405 LSB, 27.265 USB for FT8, and 27.245 USB for JS8. The group also maintains activity on PMR Channel 10 at 446.11875 MHz FM. The organization is actively seeking volunteers for roles such as webmaster (proficient in PHP, MySQL, and security), digital eQSL and paper QSL card management, logo and banner design, and country/province directors.