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This resource details the computer-optimized design of the _ZS6BKW_ multiband dipole, an evolution of the classic _G5RV_ antenna. It begins by referencing the original 1958 RSGB Bulletin article by Louis Varney G5RV, explaining the operational principles of the G5RV's flat-top and open-wire feedline on 20m and 40m, noting its impedance transformation characteristics for valve amplifiers of that era. The article then transitions to the rationale for optimizing the design for contemporary solid-state transceivers requiring a 50 Ohm match. The core of the project involves using computer modeling to determine optimal lengths for the flat-top and matching section, aiming for a VSWR of less than 2:1 on multiple HF bands. It discusses the process of calculating feedpoint impedance based on antenna length and frequency, referencing professional literature from Professor R.W.P. King at Harvard University. The analysis also considers the characteristic impedance (Z(O)) of the open-wire line, identifying a broad peak of adequate values between 275 and 400 Ohms. Specific design parameters for the improved ZS6BKW are presented, including a shorter flat-top and a longer matching section compared to the original G5RV, with a velocity factor of 0.85 for the 300 Ohm tape. The article confirms acceptable matches on 7, 14, 18, 24, and 28 MHz bands when erected horizontally at 13m, and also discusses performance in an inverted-V configuration, noting frequency shifts. The author, Brian Austin ZS6BKW, emphasizes the antenna's suitability for modern 50 Ohm coaxial cable without a balun.

A simple base loaded quarter wave vertical, which can be used on a car or portable by G3YCC

D-PRS converts these position reports from remote D-STAR radios to an APRS format. Windows .net application

A vertical half-moxon for the 7 Mhz by F6IRF

Macintosh morse code software, Fast Morse will convert any text you enter into the original Morse code equivalent, and play it on your speakers. The speed can be adjusted to anything from 1 to 35 words per minute if your computer can keep up, allowing you to send Morse signals at a rate your friends and fellow Morse enthusiasts can follow!

F5RDH project of a transverter, that can receive input in HF and convert output to 144 Mhz in french

A quarter wave vertical end-fed antenna for the 40 meters band. As all vertical antennas, also this aerial requires a good earthing system. In this project the ground is composed by twelve 4, wires buried in the lawn by using a spade to create a slit to drop the wire into.

80 meter vertical experiment by Bob Raynor N4JTE

3 Band vertical Marconi-antenna for the bands 40, 80, 160 meters with a ground net of wires as radials.

A multi-band inverted-V dipole for portable operation by GM3VLB

A homebrew fishing-rod vertical using a very nice design from EB5EKT. This antenna works 20, 30, and 40M bands by selecting the tap points using alligator clips

This article explores a theoretical model for the losses of an 80m / 40m trapped inverted V dipole antenna system using a bootstrap coax trap, but does not examine the pattern of the antenna.

An inverted V antenna for 40-80 with loading coils. This antenna is a full size on 40 and a shortened 80 by KG0ZZ.

A 5/8 vertical groundplane antenna for 50 mhz

30/17/12 and 20/15/10-Meter Tribanders and a 40 meters inverted V wire yagi antenna

This page shows a homebrew vertical antenna based on the Pac-12 antenna design.

A micro processor interface that converts PC keyboard code into Morse code

YF1AR 80 to 40 meter vertical antenna project

Maldol MFB-300 all band HF vertical antenna review by Steve Nichols

A wire yagi antenna model, easy to build, made using inverted vee elements and requiring just one support by ve3vn

A french document about Inverted V dipole antennas

Homebrew a 1/4 wave 80 meter vertical using aluminium tubing

A 10 Bands mobile antenna for about the price of 2 mobile monobanders.

A quick vertical for 160 meters portable use

The St. Louis Vertical Revisited by Dave Gauding, NF0R here are a few ideas and observations on the St. Louis Vertical

2 element reversible verticals, small footprint, big results.

A 3.5 Mhz top loaded vertical antenna built using 2 elevated radials by DJ9RB

This online tool will convert any street address into latitude and longitude and vice-versa by executing queries to several online mapping services like googlemap geocoder maporama terraserver and more by Stephen P. Morse

A self supporting vertical antenna for 80 meters by W9OY include pictures and construction details

Understanding high-frequency (HF) skywave propagation is crucial for amateur radio operators seeking to optimize long-distance communications. This resource details the fundamental principles of HF radio propagation, including the properties of electromagnetic waves, the characteristics of various HF bands, and distinct propagation modes such as skywave, ground wave, and line-of-sight. It places significant emphasis on the ionosphere's pivotal role in refracting HF waves, explaining how solar activity directly influences ionospheric conditions and, consequently, propagation paths. The resource integrates real-time monitoring capabilities, featuring dynamic charts and data from DX clusters, WSPRnet, and the Reverse Beacon Network, which allow users to track current band activity and propagation conditions globally. It also delves into advanced topics like Near Vertical Incidence Skywave (NVIS) and gray line propagation, providing insights into ionosonde data and various propagation prediction models. The site presents a detailed analysis of solar-terrestrial interactions, geomagnetic indices, and space weather phenomena, illustrating their direct impact on HF communication reliability. Practical tools and applications are highlighted, including real-time QSO planners, online Maximum Usable Frequency (MUF) maps, and alerts for solar flares or geomagnetic storms. The guide systematically breaks down complex concepts into accessible chapters, offering a structured approach to learning about ionospheric regions, diurnal and seasonal effects, and the interpretation of propagation indicators like foF2, MUF, and Lowest Usable Frequency (LUF). This makes it a robust reference for hams aiming to deepen their technical understanding and improve operational effectiveness.

Multiband and monoband HF Vertical antennas and rotatable dipoles manufacturer based in Texas USA

A telescopic pole that you adjust to suit the band you're working on , tested on 40 20 and 15 meters band by M0PZT

An 87ft inverted L portable antenna working on 80 40 30 20 15 meters band

Terrasat Communications specializes in advanced RF technology for satellite communication, focusing on _Intelligent Block Up Converters_ (IBUCs) and Solid State Power Amplifiers (SSPAs). These products are engineered to enhance satellite link performance, offering features like extended frequency ranges and high power efficiency. The IBUC series, for instance, integrates a BUC with an SSPA, enabling operators to install, configure, and monitor units for both commercial and military satellite applications, ensuring reliable, high-performance connectivity worldwide. The company's offerings support various satellite bands, including C, X, Ku, and Ka, providing solutions for diverse operational requirements. Their technology is designed for robust field performance, with products like the _IBUC2_ and _IBUCG_ models demonstrating the integration of advanced diagnostics and control capabilities, which are crucial for maintaining optimal signal integrity in demanding environments. Terrasat's focus on _SSPA_ technology underscores a commitment to power efficiency and compact design.

Radial systems for elevated and ground mounted vertical antennas by SteppIR

40 meter vertical antenna construction, a shortened easy-to-build vertical, with no-radials, made from surplus military camouflage poles

A vertical antenna specifically designed to work with the 80 meter CW beacon keyer

This page displays a 404 error, indicating the original content describing a simple _RS232 interface_ circuit is unavailable. The circuit was reportedly designed for older Kenwood transceivers and featured in chapter 22 of the _ARRL Handbook_. It likely involved basic electronic components for level shifting and signal conditioning between a computer's serial port and the radio's control interface. The intended project would have detailed the construction of a hardware interface, enabling CAT control for specific Kenwood models. Such interfaces typically convert TTL or CMOS logic levels from the radio to the +/-12V levels required by RS232, often utilizing ICs like the MAX232 or discrete transistor circuits. While the specific schematics and bill of materials are absent due to the page error, the context suggests a DIY electronics project for enhancing legacy amateur radio station functionality through computer control.

A vertical dipole for 10, 15, 20 and 40 meters made adapting two Hustler Model 6-BTV antennas by w6sdo

A home made vertical polarized moxon antenna for 144 MHz, includes dimensions, antenna pattern, SWR and antenna gain plots by WB5CXC

This project will enable you to build a monoband long wire inverted vee with 3/4 wave length sides that will have a bit of gain

A 90-foot vertical antenna constructed from **aluminum irrigation tubing** is detailed, focusing on its innovative raising and lowering mechanism. The resource describes a **45-foot ginpole** system, allowing a single operator to erect or lower the antenna in minutes. It covers the mechanical design, including the pivot base, insulated joints for the tubing sections, and guy wire attachment points. The antenna consists of two 30-foot sections of 4-inch tubing and one 30-foot section of 2-inch tubing, stacked with the smaller diameter at the top. The electrical design incorporates PVC "condulet" boxes at the 30-foot and 60-foot points, housing relays to change the effective height for multi-band operation on 160, 80, 40, and 30 meters. Ferrite rod inductive chokes are used for DC control and to tune out gap capacitance. The antenna is fed with 1000 feet of open wire line, connected to a matching transformer comprising stacked toroids and a coaxial/toroidal balun. Grounding is achieved with a 3x3 foot grid of 16-gauge tinned copper wires with soldered crossovers.

A simple vertical antenna for 70 cm band

A copper pipe Hentenna for 144 MHz. The Hentenna, a compact, high-gain loop antenna developed in Japan in the 1970s, offers approximately 5.1 dBd gain, comparable to a three-element Yagi. Adapted for 2 meters, it is crafted from copper pipe for simplicity, affordability, and broadband performance. Requiring no feed-point tuning, its construction involves soldering standard copper fittings. Installation demands non-conductive materials to minimize signal disruption. Versatile for vertical or horizontal polarization, it is ideal for FM, repeater, SSB, or CW applications. This design emphasizes practicality and performance for amateur radio enthusiasts

A vertical antenna project than can present low swr from 40 to 10 meters by using a balun in french

Produce QSL & post cards, stickers, ID cards, calendars, certificates, awards, membership applications, log and call-books, rubber stamps,T-shirts, brochures, advertising materials.

An efficient 2 meter antenna disguised as a TV Satellite dish. This vertically polarized horizontal slot antenna, cut into the reflector of a TV dish, might be the ultimate stealth antenna.

This purpose of this page is to give a brief description of a 70 MHz transverter that has been published in the Danish amateur radio magazine "OZ"

This resource details the conversion of an 80m elevated vertical antenna to include 160m operation, focusing on a relay-switched design over a trap-based approach. It presents specific feedpoint impedance values, such as **32 ohms** for 80m and **14 ohms** for 160m, and discusses the challenges of SWR drift encountered with the prior trap system during RTTY contesting. The article thoroughly explains the design choices for elevated radials, referencing _N6LF QEX data_ to debunk common myths regarding radial length and height, demonstrating that non-resonant radials can offer superior current uniformity. The construction section provides practical insights into building the vertical, including guying strategies, material selection from scrap pipe, and weatherproofing the relay assembly. It highlights the use of a common mode choke for the relay switching line, measuring approximately 5K ohms on both 160m and 80m, and details the L/C matching network's role in achieving a 50-ohm match at the end of a 300-foot RG-11 run. The author describes a precise VNA-based radial trimming procedure, achieving resonant values within a 3 KHz range. The content emphasizes the practical application of theoretical antenna principles, particularly concerning the interaction between the vertical element, cap hats, and the matching network. It offers a candid assessment of component selection, such as using junkbox parts and acknowledging the need for future upgrades to static drain resistors. The article serves as a comprehensive case study for advanced antenna builders tackling multi-band vertical designs.

This is a command-line or DOS program to convert a Cabrillo file to ADIF. The fundamental purpose is to take the output of a contest logging program (such as TRLog or CT) and prepare it for importing into a general-purpose logging program