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Experiments with phased wire vertical antennas on 40 meters at VA7ST

Presented here is a high-performance, circularly polarized omni-directional antenna that is easy to build, easy to tune, inexpensive, and will work all the mode J Low Earth Orbit (LEO) satellites

FT857 Programming Software works with FT817 FT897 too. Demo version available.

Presents the design and construction of the OK2FJ Bigatas, a portable, automatically tuned vertical antenna covering 80 through 10 meters. It details two distinct control systems: one utilizing BCD band data from Yaesu FT-857/897 transceivers, and another employing voltage level sensing for the Yaesu FT-817. The resource provides specific instructions for building the antenna's radiating element, loading coil with switchable taps, and the control circuitry, emphasizing the use of readily available components. The article outlines the physical construction of the antenna, including the use of duralumin tubes for the radiator and a PVC tube for the coil form. It specifies coil winding details, tap points, and the integration of radial wires for ground plane operation. The control electronics section provides schematics and component lists for both the BCD decoder (using a 74LS42 IC) and the voltage comparator (using an _LM3914_ bargraph driver), enabling rapid, automatic band switching without the minute-long tuning delays common in other systems. Crucially, the antenna achieves rapid band changes, with typical SWR values centered on common operating segments, such as **3.7 MHz** for 80m SSB. It also discusses modifications for CW operation on 80m and the trade-offs between antenna efficiency and full-range automatic tuning on higher HF bands, where manual adjustment of radiator length is suggested for optimal performance on 15m, 12m, and 10m. The resource includes construction photos and a discussion of cable requirements for reliable operation.

JJ0DRC's HF multi-band delta loop antenna project, initially conceived during the waning peak of Cycle 23, addresses the common challenge of achieving effective DX operation from a small residential lot in Japan. Dissatisfied with a ground plane antenna's performance in SSB pile-ups, the author sought a beam-like solution without a tower, drawing inspiration from a JJ1VKL article in CQ Ham Radio Sep. 2000. The antenna, constructed in October 2000, employs two 7.2-meter fishing rods (37% carbon fiber, reinforced with cyano-acrylate glue and aluminum tape) and 1mm enameled wire, fed by an Icom AH-4 external antenna tuner. While the exact beam pattern remains unmeasured, JJ0DRC observed a significantly higher callback rate compared to dipole antennas, particularly on higher bands. The system's circumference length of 15-20m is crucial for maintaining a good beam pattern across HF bands, though performance on lower bands like 80m, 40m, and 30m becomes less directional as the length deviates from a full wavelength. Ongoing maintenance addressed degradation issues, including aluminum tape cracking and wire breakage at connection points due to strong winds (often exceeding 10-15m/s in winter). The author reinforced rod connections with IRECTOR PIPE SYSTEM components and INSU-ROCK ties, and improved wire attachment methods using Cremona rope and epoxy bond to enhance durability.

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

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.

ShipPlotter displays complete information about ships that are within VHF range of your position using the Universal Automatic Identification System (AIS).

Using the FT-857 Microphone Jack for Serial Control (CAT)

Based on the N2PK design, this swr meter use a stockton directional coupler

Shareware program to receive and transmit high speed CW (morse code) used in MS (amateur radio communication mode) with MS Windows 95/98 and sound card.

Dedicated ham radio internet gateway and server system. It is intended for use by RF gateways and PC users connected to the internet

US Amateur Radio Band Plans by ARRL

Built around a 1/2" pvc frame, Larry's 6 meter moxon antenna is made from #8 aluminum ground wire

Double bazooka antennas

"A collection of nearly all facts around the YAESU Musen products; products, company history and much more"

This is a simple calculator for solving the antenna wire catenary between to end points given the design wind speed, mass per unit length of the wire, wire diameter and Gross Breaking Strength of the wire.

How to make easily your N-type connector, pictures and procedure, step by step

This antenna was designed to meet the requirements of a light body worn small magnetic loop covering all the frequencies continuously from 7 MHz to 29.4 MHz

Design for a 5 element beam on a 23 foot boom with an unusual combination of performance characteristics

HF pedestrian operation using loop antennas by PY1AHD

Amateur Radio, Citizen's Band Radio, Commercial Radio, General Electronic items, Marine Radio, and Short Wave Radios, Hamilton Ohio

Build your own home made Antenna Analyzer with an arduino micro, or a cheeper one with a pic processor

SSTV Fundamentals, frequencies in use for SSTV and many SSTV related infos, includes Fax basics

Edited by Oz6OM to find out who's on 50MHz expeditions anywhere around the world. Most recent news on the web.

CwType v2.35 provides a dedicated terminal interface for **CW operators**, facilitating Morse code transmission from a Windows PC. Users can input characters via the keyboard or a connected paddle, supporting iambic keying. The software manages transceiver control, including PTT and CW keying, through COM or LPT ports. It offers adjustable speed, dash/dot ratio, and inter-letter spacing, with real-time speed display in LPM and WPM calculated by the "PARIS" method. The program includes features like MOX mode for automatic TX on/off, configurable weighting to compensate for transceiver element clipping, and programmable F-key macros for sending predefined text or special sequences. CwType can integrate with logging software such as AALog (V1.0.3 and later) for data transfer, and supports various character sets including English, Russian, and Swedish. A beacon mode is also available, executing the Alt-F12 macro periodically at a user-defined interval. Audio output for monitoring can be routed through the internal PC speaker or a sound card, with options for sine waveform and smooth envelope generation for SSB transmitters. The software is compatible with **Windows XP/Vista/7/8/10** and is distributed as freeware.

Improvements to Using the Heath SB-200 Linear on Six Meters by Ron Klimas, WZ1V

Eham IC-718 reviews

Articles and original manuscripts on RF power amplifiers

Guy wire sloper antenna suitable for the 10m band

A table with Loss in DB/100m , Max power in Watts, Diameter in mm , Velocity factor (VF) expecially in VHF UHF and Microwave

Windows freeware database containing frequencies, locations, and a small logging program capable or recording audio

Improved Helical Antenna Design for 802.11b WLAN by PA0HOO

IC-746 radio control program in italian and personale info

What do you do with a bunch of old computer power supplies?

Thermocouple ammeters are very rare these days, but the job they were perfect for - measuring antenna currents - is still a modern requirement especially in respect to groundplane currents. By David A. Reid PA3HBB G0BZF

The I0JXX is an italian company that offers market their projects, also sells electronic products of high quality, both for Ham, both Broadcast and their accessories. VHF Antennas, mosfet power amplifiers, filters, insulators, power dividers, telescopic poles, antenna masts

located in the heart of Southern California, is dedicated to the advancement of Ham Radio

LogDDM, a freeware logging application, supports the tracking of over **100** different awards, including _DXCC_, WAZ, and WAS, directly within its interface. This software facilitates comprehensive log management for amateur radio operators, integrating functionalities such as a built-in callbook lookup, real-time packet cluster access, and direct rig control for various transceivers. It also offers robust import and export capabilities, primarily utilizing the ADIF format, which is essential for submitting logs to award sponsors or transferring data between different logging platforms. Developed by Giorgio, IV3DDM, the program is designed to streamline the logging process, allowing hams to efficiently record contacts and manage their QSL information. It provides a centralized hub for operational data, from initial QSO entry to final award application. Key features include detailed QSL management, support for multiple operating modes, and a user-friendly interface, making it a practical tool for daily operating and contest logging.

F6CHT plan for a multiband yagi antenna that covers 6 to 30 meters band in french

A full duplex antenna system for 144 432 Mhz

Morse Keys by Gordon G4ZPY

Dutch society of collectors of old ex-military radio equipment and other nostalgic receivers and transmitters

CB distributor in the Netherlands since 20 years

Yaesu official FT-100 icons sheet

Radio spectrum monitoring and analysis tools for industry and government

Overview, summary, tutorial about the log periodic antenna or aerial used for wideband RF antenna applications

Very strange morse keyers, like Onion chopper CW key, Handshake CW key, Chopsticks CW key, Typewriter CW keyboard, Refrigerator CW key by OH6DC

W5JGV antenna tuner for 150 - 500 Khz band