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The G5RV multiband HF antenna, designed by Louis Varney (G5RV) in 1946, is a popular compromise antenna offering good overall performance on most HF bands when paired with an external antenna tuner. The basic full-size G5RV measures 102 feet across the top for 80 through 10 meter operation and is fed at the center via a 34-foot low-loss feed-stub. This interaction between the radiating section and the feed-stub facilitates matching across 80-10 meters with a standard tuner, often eliminating the need for ladder line directly to the shack. The antenna's design center frequency is 14.150 MHz, configured as a 3/2-wave dipole on 20 meters, with its 102-foot length derived from long-wire antenna formulas. Construction details emphasize the matching section, which can be open wire, ladder line (window-type), or TV twin lead. Each type has a specific velocity factor (VF) affecting its physical length for an electrical half-wave on 14 MHz; for instance, open wire requires 33.7 feet (VF 0.97), ladder line 31.3 feet (VF 0.90), and TV twin lead 28.5 feet (VF 0.82). The article provides formulas for calculating these lengths and discusses the antenna's behavior on individual bands, from 3.5 MHz where it acts as a shortened dipole, to 28 MHz where it functions as two three-half-wave long-wire antennas fed in-phase. Practical construction notes include recommendations for vertical descent of the matching section, sealing the coax junction, providing strain relief, and winding a coaxial choke coil to mitigate common mode current. The resource also presents dimensions for double-size (204 ft) and half-size (51 ft) G5RV versions, along with their corresponding matching section lengths for various line types, making it a versatile reference for hams considering this classic wire antenna.

The GW3YDX Super Moxon antenna design improves upon the standard Moxon Rectangle by incorporating additional directors in a rectangular configuration, yielding enhanced directivity and gain. For the 6m version, modeling with 4NEC2 and EZNEC+ indicated a 3dB gain increase and a 26.5dB front-to-back ratio, with VSWR below 1.5:1 between 50.0 and 50.3MHz when optimized for 50.1MHz. This design achieves a narrower -3dB power point beamwidth of 60° compared to the original Moxon's 80°, contributing to better QRM rejection. The boom length for the enhanced design is just under 2m, approximately double the original Moxon's, with no increase in wingspan. Construction details include tubing lengths for 6m, 4m, and 2m versions, with specific dimensions provided for elements A through M, measured to tubing centers. For instance, the 6m version uses a 2160mm element A and a 2140mm element H. The design maintains a 50-ohm feed impedance, with practical models showing VSWR plots consistent with simulations after minor adjustments to driven element lengths. The article also references Moxgen software for initial Moxon parameter calculation and NEC/EZNEC model generation. The 2m Super Moxon version measures approximately 30" x 25", demonstrating the compact nature of the design across different VHF bands. The article highlights the antenna's performance in real-world DX contacts on 6m, achieving contacts with over 80 stations in the USA from a modest QTH.

A Slinky-based doublet or loaded vertical QRP antenna tested for 40 meters band

Optimizing a G5RV or ZS6BKW multiband wire antenna for HF operation often involves addressing common SWR issues and understanding feedline characteristics. This resource chronicles the construction and performance evaluation of a G5RV, initially built for 80m, 40m, 15m, and 10m bands, by a newly licensed Foundation operator. The author details the selection of materials, including 3.5 mm stainless steel wire for the doublet arms and enameled copper wire for the open-wire feeder, and the initial decision to omit a balun based on common online information. The narrative highlights the initial disappointing performance, characterized by high receive noise and poor signal reports on 80 meters, despite the transceiver's internal ATU achieving a 1:1 match. This led to experimentation with a coax current balun and further research into G5RV myths, such as SWR claims and the necessity of a balun. The author then describes modifying the antenna to the ZS6BKW configuration, which involves specific changes to the doublet and feedline lengths, and integrating a 1:1 current balun wound on a ferrite toroid. The modifications resulted in improved reception and transmit performance across the bands.

One point eight MHz to 30 MHz is the operational bandwidth for this 4:1 Ruthroff voltage balun, designed to interface an unbalanced T-Match network with a balanced antenna system. The project details the construction using a _T200-2_ powdered iron toroid core, tightly wrapped in PVC electrical tape for insulation, and wound with 17 double bifilar turns of 1.25mm enamelled copper wire. This outboard balun offers flexibility, allowing hams to trial various baluns based on antenna system and impedance characteristics, rather than integrating it directly into the tuner. The resource includes a schematic of the balun, a wiring diagram showing winding connections, and a table suggesting alternative toroid cores like the T80-2 or T400-2 with corresponding winding counts. Component sourcing is straightforward, listing items such as the _Amidon_ T-200-2 core, SO-239 connector, and a sealed polycarbonate enclosure from Jaycar. Performance evaluation was conducted using an _AIM 4170C_ antenna analyser, demonstrating efficient 1:4 voltage transformation across the specified HF spectrum. Further efficiency tests involved measuring RF power loss at various frequencies, revealing minimal loss—less than 0.7 dB from 3.6 MHz to 30 MHz, and only 2.0 dB at 1.8 MHz. These measurements, performed under ideal 50-ohm conditions, confirm the balun's effectiveness as a low-loss interface for multi-band antenna systems. The page also links to several other balun and unun projects, including 1:1 current and voltage baluns, and 9:1 voltage ununs, providing a broader context for impedance matching solutions.

probably the most simple and inexpensive antenna you could make for 23cm.

The 1960s mobile/base antenna returns, double G Whip for base use.

Demonstrates the construction of a double bazooka antenna, detailing its historical development from MIT radar applications in the 1940s to amateur radio use in the 1950s. It explains the antenna's operation as a 1/2 lambda coaxial section with open-ended stubs, acting as a shortened quarter-wave stub at resonance, presenting high impedance. The resource provides formulas for calculating total length (LT = 140/Freq) and coaxial length (LC = 99/Freq) for RG58 CU, along with specific instructions for cutting and soldering components, including a central insulator and end wires. Compares the double bazooka to a standard dipole, highlighting its 98% efficiency and twice the bandwidth. It claims a +3.6dB gain over a dipole (dipole gain 2.15dB) and a 6dB reduction in reception noise due to its closed design, which also minimizes harmonics and TVI. The antenna handles over 1.5kW (2kW PEP) without performance degradation and is effective for DX with a low radiation angle, especially when configured as an inverted V between 90° and 120° with ends 2 meters above ground. It eliminates the need for a balun and can be fed directly with 50-ohm coaxial cable.

An extended double zepp antenna by F5ZV in french

A 5/8 wave antenna, can be fed with ladder line from the center insulator to tuner.

Here is a review of the 40 and 80 meter band Double Bazooka antennas as used on the HF shortwave bands.

The Yaesu VX-5R, manufactured between 199x and 200x, offers a transmit frequency range covering 50-52 MHz, 144-146 MHz, and 430-440 MHz for European models, with US versions extending to 50-54 MHz, 144-148 MHz, and 430-450 MHz. Its receiver boasts an impressive wideband capability from 0.5 MHz to 999 MHz, with cellular frequencies blocked in some regions. The unit provides up to 5 watts RF output on 6 meters and 2 meters, and 4.5 watts on 70 centimeters, with selectable lower power settings down to 300 mW. This handheld transceiver utilizes a double conversion superheterodyne receiver system, featuring a 47.25 MHz first IF for FM and 45.8 MHz for WFM. Key specifications include a frequency stability of ±5 ppm across a wide temperature range and a current drain of 25-150 mA on receive. The VX-5R supports 220 regular memory channels with alpha tags, 3 home channels, and 10 NOAA weather channels, all stored in non-volatile EEPROM. Additional features include CTCSS/PL and DCS with tone search, ARS, ARTS, an internal voltmeter, and a Spectra-Scope. The device operates on a 7.2 VDC battery pack or 10-16 VDC external power, weighing 255 grams with dimensions of 58x88x27 mm. The VX-5R was also available as the metallic silver VX-5RS.

Building the double size G5RV antenna, part list, assembly part, dimensions and assembly instruction in a pdf document

Demonstrates the _SQUIRL Field Day Logger_, a specialized software tool designed for efficient contact logging during the annual ARRL Field Day event. The resource details its core functionality, which includes real-time logging to easily readable text files, with filenames structured by callsign, band, and mode (e.g., K8DAA-20M-SSB.txt). It highlights features such as a real-time history grid of previous contacts, a dynamic USA and Canada map displaying contact locations, and a duplicate checker that provides audio notifications and pre-fills class/section data for previously worked stations. The software also includes an ADIF export function, enabling users to transfer logs to other general-purpose logging programs. The software's design emphasizes simplicity and ease of use, allowing for rapid on-the-spot training, as noted by users like W4CMB. It supports various operating systems, including Windows 98 through 8, and has been successfully run on Linux via _Wine_. Key usability enhancements include a "double-size" feature for improved readability and a "Space Mode" for quick field navigation. The version history indicates continuous development from 2001 to 2013, with significant additions like the real-time Field Day Map in 2003 and ADIF export in 2004, which allows for seamless integration with other logging platforms.

The Double 5/8 is a natural extension of the Single 5/8 and uses a 5/8λ element for both the top and bottom radiators.

The Double Bazooka Dipole is a very efficient single band antenna which is very quite,and does not require the use of a balun. This antenna consists of coax (RG58) with the shield split at the center and the feedline attached to the open ends.

The HF horizontal loop has been around for many years now. This article includes a YouTube video and discusses the reasons for looking at this antenna, its design, and its installation. There are some on-air comparisons against three regular double bazooka (coax) dipoles and the Par SWL End-Fed antenna.

The vertical Double-Zepp 2x7 m is a very simple, effective 8-Band-antenna. The end of the Dipol must be 5-10 m above the ground

Double T Bar Vertical antenna are vertical antenna with cross bars on the top and bottom. These crossbars provide capacitance loading thus reducing the size of the antenna

This simple antenna modelling windows software by F5IMV wil calculate a dipole,extended double Zepp,G5RV, ZS6BKW and many other wire antennas by F5IMV

Approximately 190–209 words of content are available, including previously unreleased **radio intercepts** from the Russian army during the Battle for Kyiv, with confirmed authenticity. The platform provides extensive news coverage, video reports, and analytical content focusing on Ukraine and international affairs, frequently publishing exclusive materials. Recent articles cover topics such as emergency power outages in Kyiv, discussions on Iran's nuclear program, and Belgium's policy regarding temporary protection for children born after Russia's full-scale invasion. The site also features in-depth investigations into Russian military losses, the political isolation of Hungary within the EU, and mental health advice for coping with wartime stress. Timely updates are provided throughout the day, detailing events such as drone incidents in Lithuania and proposed restrictions on military personnel's access to gambling in Ukraine. The platform offers a variety of multimedia content, including video and photo reports on events like the double explosion in Bucha and search operations for victims of the Volyn tragedy. Editorial selections delve into topics such as parliamentary elections in Slovenia, internal political conflicts in Ukraine, and the export of Ukrainian drones to the Middle East, alongside historical analyses and opinion pieces from various contributors, often featuring expert commentary and reader engagement. The content is primarily focused on current events and geopolitical analysis, with a strong emphasis on the **Ukrainian conflict**.

Details the construction of an **HF converter** designed by M1GEO, George Smart, specifically to extend the frequency range of the FunCube Dongle Pro (FCD) for amateur radio reception. The FCD natively covers 64 to 1,700 MHz, but this project enables reception from 0 Hz to 64 MHz by up-converting signals to the FCD's operational range. It employs a **double-balanced mixer** with a 100 MHz local oscillator (LO) to translate incoming HF signals; for instance, a 1 MHz signal appears at 101 MHz within the FCD's passband. The design incorporates a 7th-order Chebyshev low-pass filter with a 62 MHz cutoff frequency at the input to mitigate image frequencies, ensuring cleaner spectral presentation. George provides the schematic, PCB masks, and Gerber files for replication, noting that Far Circuits also offers PCBs. The resource includes test results for the low-pass filter and measurements of LO leakage, identifying -36.8 dBm at 100 MHz as a potential sensitivity concern. M1GEO discusses potential improvements, such as adjusting the mixer's LO drive, adding a balance pot, or incorporating a post-mixer high-pass filter to reduce LO breakthrough. Audio recordings from 40m and 17m demonstrate the converter's performance with WRplus SDR software.

Setting up HF10 a solution for those having limited locations and wanting a low visual impact aerial by G4LDS

Building a Double Extended Zepp Antenna

Some notes on double-shielded coaxial cable

A synthesized 2.3 GHz Amateur Television (ATV) transmitter design, conceived by Ian G6TVJ, is presented, targeting broadcast-quality video performance on the 13cm band and extending up to 2.6 GHz. The core of the design utilizes a commercial Z-comm Voltage Controlled Oscillator (VCO) that tunes from 2.2-2.7 GHz, providing a +10 dBm output and simplifying RF alignment. This VCO's stability, originally intended for narrowband applications, readily accepts high-frequency video modulation, contributing to the transmitter's robust performance. The exciter stage, incorporating a Mini Circuits VNA 25 MMIC amplifier, boosts the signal to +16dBm, while a Plessey SP4982 prescaler divides the output frequency for the synthesizer. The synthesizer employs a Motorola MC145151 CMOS parallel IC, favored over the common Plessey SP5060 for its superior video modulation characteristics and ease of programming without microprocessors. This choice addresses issues like LF tilt and distorted field syncs often seen with SP5060 designs, particularly when operating through repeaters or over long distances. The MC145151 divides the signal further, enabling precise frequency stepping, with programming handled by EPROMs for channel selection and LED display. The loop filter network, critical for video integrity, was developed through experimentation to prevent the PLL from reacting to video modulation, ensuring a clean transmitted picture. The transmitter incorporates a Down East Microwave commercial power amplifier module, delivering approximately 1.6W output, driven by the exciter through a 3dB attenuator. Construction involves surface-mount SHF components on micro-strip lines etched onto double-sided fiberglass board, housed within a tinplate box. The design boasts no AC coupling in the video path, preserving low-frequency response, a common failing in other ATV transmitters. Performance tests with a 50Hz square wave revealed no LF distortion, and a calibrated "Pulse & Bar" signal showed a near 100% HF response, demonstrating its capability for high-quality ATV transmissions.

Noise Canceller kit originally developed about 1989 by G4WMX and GW3DIX and improved by DK9NL and DG0KW.The VK5TM Noise Canceller is another version of the design, with the HF Vox circuit removed and a couple of other minor changes, including the use of SMD JFETs and a double-sided pcb.

An home made doblet antenna made with two Slinkys that are aproximately five meters in length connected with a twin-feed connected to a balanced ATU

Low Band Receiving Antenna, it is a ground independent Receiving antenna which only needs two 10m support poles by DH1TW

A portable wire antenna for the HF bands, made with a common speaker wire. In its natural form, the speaker wire acts as parallel feed line coming up to the bottom of the PVC feed point. From there, it's split into two wires, one heading out each side of the PVC tee.

Operating Morse code (CW) relies on a diverse array of **telegraph keys**, each with unique characteristics and historical significance. This resource presents a personal collection of such keys, offering visual documentation and details on various models. It features early Marconi keys from the 1900s, including specific models like the Marconi Air Ministry Key and Marconi Coastal Station Keys, alongside **Vibroplex** bugs and JRC keys. The collection also highlights rare items such as the Brown Brothers Magnetic Twin Paddle Key, the Eddystone Bug Key, and Swedish SRA Ericsson Keys. Enthusiasts can view examples of GPO Double Current & Single Current Keys, Navy NATO Keys, and specialized aircraft and maritime keys. The site includes information on historical training devices like the OMNIGRAPH and a Morse Inker from 1900, providing context for the evolution of telegraphy equipment. Additionally, the resource showcases unique items like the B2 Spy Set SOE Agents Key and a WW2 Junker U-BOAT KEY, illustrating the varied applications of Morse keys throughout history. The author, G0RDO, also shares details on a home-made paddle key and invites inquiries for acquiring interesting Morse keys.

Constructing a high-performance RF spectrum analyzer up to 1000 MHz requires careful attention to component selection, shielding, and circuit isolation. This resource details a project that improves upon the _Spectrum Analyzer for the Radio Amateur_ design by Wes Hayward (W7ZOI) and Terry White (K7TAU), incorporating ideas from Scotty Sprowls' project, particularly his 1013.3 MHz IF bandpass cavity filter. The analyzer utilizes a Mini-Circuits SRA-11 mixer with a sweeping local oscillator from 1013 to 2013 MHz, feeding into a 4-pole copper pipe cavity filter. The design employs a second SRA-11 mixer with a fixed 1024 MHz LO to produce a 10.7 MHz final IF. This signal then passes through narrowband resolution filters and is processed by Analog Devices AD603 and AD8307 ICs for IF amplification and logarithmic detection, driving an oscilloscope in X/Y mode. The project emphasizes modular construction, using salvaged components and double-sided FR4 material for PCBs, with critical notes on minimizing spurious images through effective shielding and proper voltage regulation for each module. Key components include a Z-Communications V585ME48 VCO for the first LO and a Z-Comm V583ME01 VCO controlled by a Motorola MC145151 PLL for the second LO. An optional Hittite HMC307 step attenuator and K&L 5L121-1000/T5000-O/O low-pass filter manage RF input. Tuning procedures for the 10.7 MHz IF resolution filter are also detailed, showing before-and-after spectrum views.

Maxcon makes and sells Amateur Radio Antennas. Double extended Zepp antenna, multiband dipoles, bazooka antennas, and VHF Jpole, made in USA

The Hentenna is an Asymmetrical Double Rectangle (ADR) Loop Antenna originally designed by Japanese Hams operating on the 6 m Band in the 1970s.

Sort of similar to the one of the 6m omni. Instead of using twin-lead, this design makes use of a more or less regular double bazooka antenna (coaxial dipole). Your attention shall be drawn to the available standart literature, such as Rothammel. In order to "compute" the dimension, Karl Rothammel mentioned that the total length of the dipole shall be 95% of the free-space wavelength. The short-circuit bridges (closing the folded dipole) are to be placed at a distance-fraction being equal to the velocity factor of the coax cable used, which will be 66% using RG-58 or RG174.

Developing operational amateur radio equipment for the 134 GHz band presents significant technical challenges, particularly in frequency generation and stability. This resource details the construction of a 134 GHz system, outlining its architecture with separate transmit (Tx) and receive (Rx) modules, each employing a local oscillator (LO) and RF head units. The system utilizes a dual Flann 50 GHz lens-type horn antenna configuration for optimal signal coupling. The transmit path incorporates an LMX2541 synthesizer chip operating at approximately 2.8 GHz, referenced by a 10 MHz double-oven Morion OCXO for exceptional stability. This signal is multiplied through a series of stages (X4, then X2) to generate a 22.4 GHz signal, which subsequently drives a dual series diode multiplier to produce the final X6 signal for 134 GHz operation. The receive side features an anti-parallel diode mixer coupled to a 144 MHz transceiver via a preamplifier, ensuring effective downconversion. Operational mode is CW, achieved by keying a multiplier stage. The project includes images of the Tx and Rx head units and describes a successful 3.5 km test with G8ACE, demonstrating stable signal tones due to PLLs locked to OCXOs at both ends, confirming the system's robust performance.

Documents the operational experiences and technical insights of amateur radio station VA3STL, offering a firsthand account of various on-air activities and equipment. The blog features a detailed narrative of a **QRP transatlantic QSO** on 12m SSB, achieving a 55 report with 10W to a mobile station in Italy using a homebrew 90ft doublet antenna. It also introduces the _Ten-Tec 539_ QRP HF transceiver, a 10W output rig covering 80m through 10m, designed for portable operations and featuring DSP and dual VFOs. The resource also delves into historical radio technology, specifically the "Gibson Girl" survival radio, an emergency transmitter operating on 500kHz (and later 8280/8364 kHz) with a hand-cranked generator and kite-deployed antenna. This section explores its origins from German designs and its use during World War II, including its distinctive curved shape for ergonomic hand-cranking. Further historical content includes a visit to Signal Hill in St. John's, Newfoundland, commemorating Marconi's reception of the first transatlantic radio signal in 1901. The post describes the Cabot Tower exhibit and the VO1AA station, highlighting the site's significance despite the thick fog during the visit. It also showcases a homebrewed _Marconi-style straight key_ by WB9LPU, crafted to celebrate the centenary of Marconi's achievement.

Online antenna calculator for homemade double biquad antenna for UMTS 3G 4G WiMAX WiFi frequencies. Article includes also a simple biquad antenna for 4g

The structure of this dual band VHF UHF antenna is very simple. It consists of two identical square loops, whose sides measure a quarter wave, connected together at the ends. A project by I5NZR

The BikeLoop antenna project details the construction of a double magnetic loop antenna optimized for VLF frequencies, specifically around 136 kHz. This innovative design incorporates two orthogonal loops, which significantly enhance reception capabilities. Key construction hints include utilizing lightweight bicycle rims for the antenna structure, making it easy to transport and set up in various locations. The document provides valuable mathematical and electrical insights into the antenna's performance, alongside practical reception tests conducted in the Italian Alps, showcasing its effectiveness in capturing various VLF signals, including Sferics and FSK transmissions. Proper setup is crucial for optimal performance. The project emphasizes the importance of grounding and avoiding interference from nearby electrical sources. The reception tests revealed the antenna's ability to capture a range of signals, demonstrating its practical application for enthusiasts interested in VLF reception and antenna experimentation. Overall, the BikeLoop serves as an excellent starting point for those looking to explore the world of VLF frequencies and enhance their antenna-building skills.

An easy to build double quad antenna that can be used as an antenna for beginners, it features a wide angle providing a generous alignment.

Extended Double Zepp measurements for all ham bands, and online calculator. The antenna is constructed much like an ordinary Dipole antenna but with 5/8 Wavelength Elements matched with an added Impedance Matching Section of balanced feed line

Originally designed by John Kraus, W8JK in about 1940, this antenna has some interesting properties. The W8JK antenna is 2 (Two) centre-fed double-dipole fed by a pair of anti-phase signals. Small size, simple antenna, offer nice performance but need a tuner. Tested in this project from 30m to 6m bands

Home made 40 meter transceiver project. The receiver is a Progressive Receiver with a few modifications. The Transmitter is a modified MFJ Cub circuit. Includes schematic and circuit diagrams for Receive Input Filter, 3-Pole 500 Hz Cohn Filter and 7 MHz Double Tuned Bandpass Filter

MLog 0.8d is a freeware logging software designed for Windows operating systems (NT, 98, ME, 2000, XP) that facilitates the logging, management, and analysis of amateur radio QSOs. It features a customizable input mask for rapid contest logging, a robust search function for existing contacts, and immediate data storage in CSV format to prevent data loss. The software also includes a double-check mechanism against reference logs during callsign entry, integrated DXCC information, and a "magic field" for streamlined data input, all within a single-window interface. Key functionalities include graphical QSL card management via _QSL-Collection_, CW output through soundcard or PC speaker, and direct access to _Radio Amateur Callbook_ data. MLog supports transceiver control via _Ham Radio Deluxe_ URLs, offers a detailed world map with locator conversions, and can launch _VOACAP_ through _HamCap_. It provides extensive data analysis options for QSLs, _Locator_ large fields, _DOKs_, _DXCCs_, QSO counts, and user-defined contest evaluations, alongside flexible import/export capabilities for various log formats.

A transmitting antenna 2x15m, about 100 foot doublet antenna fed by a ladder line of about 600 Ohm. Article in Polish and English,

EA4EOZ details the construction and testing of 50 MHz traps, a critical component for multiband antenna designs. The project addresses the challenge of sourcing high-voltage capacitors suitable for trap applications, exploring alternatives to expensive doorknob capacitors. The author successfully fabricated a capacitor using 1.6mm double-sided FR-4 PCB material, achieving a capacitance density of **2.6 pF/cm2**. Utilizing the _VE6YP calculator_, specific L and C values of 30 pF and 0.31 uH were determined for a 2cm diameter coil. Both the FR-4 PCB trap and a coaxial cable trap, constructed from _RG-58_, were built and tuned to approximately 50 MHz using a spectrum analyzer. The coaxial cable trap demonstrated superior performance, exhibiting a notch nearly **20dB deeper** than the FR-4 version. This practical comparison provides insights into trap construction for experimental antennas, with the coaxial cable trap selected for an antenna project intended for operation at up to 100 watts.

This is basic instructions for homemade 4G Antenna working on 2600 MHz UMTS featuring 13 14 dBi gain. This antenna is desigend to resonate on microwave frequencies in two segments from 2500 to 2570 MHz for Uplink, and from 2620 to 2690 MHz for Downlink.

The multiband tuned doublet, or center-fed Zepp, is a simple and efficient HF antenna that operates effectively across most amateur bands using a balanced parallel-wire feedline and antenna tuner. Unlike coax-fed dipoles, it tolerates impedance mismatches with minimal loss. By selecting suitable feedline and dipole lengths, one can achieve stable multi-band operation. While it doesn’t match monoband Yagis, it offers excellent performance, low cost, and broad coverage. Its radiation pattern and efficiency vary with frequency, but it remains a practical and versatile solution for HF operators.

Constructing a double bazooka antenna for the UHF band, specifically tuned for 435 MHz, involves a straightforward process detailed with step-by-step imagery. The design leverages readily available _RG213 coaxial cable_, cut to precise lengths derived from formulas: 140.208 / F (MHz) for the radiating element and 99.06 / F (MHz) for the coaxial section. This approach yields a highly effective vertical polarization antenna, suitable for local ragchewing or repeater access. My own field experience with similar coaxial designs confirms their robustness and ease of deployment. The article emphasizes critical steps like short-circuiting cable extremities, interrupting the braid at the center, and securing an insulating support. It also covers preparing the definitive mounting with a quality feedline, noting that RG58 is acceptable for temporary use but better options exist for permanent installations. Weatherproofing is crucial for longevity, achieved through PVC electrician's tube, glue, and heat-shrink tubing. The final assembly is designed for mounting on a small aluminum mast, with the feedline routed internally. The reported SWR measurement is very satisfactory, showing approximately **+/- 3%** HF return, indicating excellent impedance matching at the target frequency.