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CW paddle made with a steak knife some simple hardware and a stainless steel fork

A folded wire antenna for 160 meters as appeared on 73 amateur radio magazine june 1997

A marriage of the windom and slinky antennasm, article by NC4TC

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.

Google map beacon map on 10 meter

A compact multiband wire antenna suitable for portable operations.

Lookup callsigns in locator, or locator of a specified callsign and display in google map

Constructing an effective mobile antenna system for HF bands often presents challenges in achieving multi-band operation with a compact footprint. This project details the assembly of a versatile mobile antenna utilizing a standard _Hamstick_ base, enabling operation across 40, 20, 15, and 10 meters. The design incorporates a 102-inch whip and a custom-fabricated coil, allowing for quick band changes by adjusting the coil tap point. The document provides a parts list, step-by-step assembly instructions, and tuning considerations for optimizing SWR on each band. It emphasizes practical construction techniques for the coil and mounting hardware, ensuring mechanical integrity for mobile use. The antenna's performance is discussed in the context of typical mobile operating environments, highlighting its adaptability for various HF frequencies. Final adjustments involve precise trimming of the whip and coil taps to achieve resonance, with a focus on minimizing losses and maximizing radiation efficiency.

If you want to interface the IC-746 Pro or any other Icom rig with a computer for rig control, an outboard CI-V CAT device is required.

A monoband antenna with large bandwidth in French

ARRL comparison of HF transceivers, including Elekraft, TenTec,Icom, Yaesu and Kenwood recent transceivers based on QST product reviews

Excel spreadsheet that help calculating dimensions of a high efficiency magnetic loop antenna for HF bands. Giving in input the loop perimeter, loop diameter and loop conductor will calculate electric characteristics, bandwidth, and efficiency

This project was published in the April 2004 issue of the Australian magazine Amateur Radio, and has been designed using parts which are very readily available.

Presents the mechanical and electrical specifications for a 5-element Yagi beam antenna designed for the 6-meter band. The resource details element lengths, spacing, and boom dimensions, specifically utilizing _EMT conduit_ for construction. It includes a diagram illustrating the element layout, a coaxial balun connection, and a reported SWR curve, providing a practical blueprint for hams to replicate the design. The design achieves a reported SWR of **1.1:1** at 50.125 MHz, indicating efficient impedance matching across the primary 6-meter DX window. The boom length is specified at 2.44 meters (8 feet), with element lengths ranging from 2.87 meters for the reflector to 2.59 meters for the director 3. This configuration suggests a gain figure typical for a 5-element Yagi, likely in the range of **9-10 dBi**, making it suitable for local and sporadic-E DX contacts.

This application note is designed to help the reader understand how balun transformers can be used in today's RF/Microwave communication applications.

IC‐2300 MARS/CAP mod expanded frequency range 136‐174 MHz

A simple circuit which will generate a 700 Hz tone into any FM transceiver allowing an amateur to practice CW with another amateur on a 2 meter simplex frequency.

W3EDP multiband wire antenna, an extensive study and analysis of this antenna by W0ESE

The PDF document, titled "J-Poles," presents various J-pole antenna designs covering the 50 MHz to 450 MHz frequency range. It includes construction details for several specific bands, such as a 6-meter J-pole, a 2-meter J-pole, and a 70-centimeter J-pole. The content outlines the fundamental principles of J-pole operation, including the quarter-wave radiator and half-wave matching stub. Each design features specific dimensions for elements like the radiator length, stub length, and spacing, often expressed in inches. The document also discusses feeding arrangements and impedance matching considerations inherent to J-pole antennas. It provides practical guidance for homebrewing these antennas using common materials like copper pipe or wire elements. The resource offers insights into the advantages of J-poles, such as their omnidirectional pattern and ease of construction, making it a practical reference for radio amateurs interested in VHF/UHF antenna projects.

Progress in Design of Extremely Short Transmitting Antennas Short and still efficient, how is that possible? By Juergen Schaefer, DL7PE author of the MicroVert antenna concept. The MicroVert introduced in this document is an extremely short and hardly visible short-wave antenna with outstanding radiation properties

A project for a homemade multiband Hexbeam antenna for 10, 12, 15, 17 and 20 meters

Gap Titan DX Antenna manual. This is an enhanced version of the common Gap Titan DX Manual document you can download from other sites. This manual is in PDF Format.

Transverter for 70MHz, a project by G3XBM

English version of the Yaesu FT-7800 operating manual

An interesting article with many technical details on a phased delta loop array for 80 meters band includes pictures of antenna relays

This is a 6 band receive only filter designed to protect your receiver front end and provide 45dB reject at the stop bands. This is a 6-band receive only filter designed to protect your receiver front end and provide 45dB reject at the stop bands. Stop band reject may be limited by the relay isolation. Worse case isolation is at 28 MHz or 35 dB or better. Relay K3/K8 protects the filter during transmit via the PTT line. A 25-50ms delay must be used between transmit and PTT. Do not rely on your radio to provide adequate delay with out using the PTT. You logging software must be set to allow a delay between PTT and time of 1st transmit. This filter will not work with VOX or QSK keying as you will damage the filter.

F5DQK repairing and swr measurement tests of a Cushcraft R7 Antenna

KG4JJH moxon assembly plan for the 50 Mhz in a pdf file

The **70cm Moxon Beam** project outlines the construction and testing of a compact, directional antenna for the 432 MHz band. G3XBM recounts his early 1980s experience with a 4W FM321 transceiver and a Jaybeam 48-element TV antenna, which provided a baseline for his later UHF antenna experiments. This project focuses on a simpler, yet effective, design for local and regional contacts, emphasizing ease of construction and practical field results over complex theory. The article details the specific dimensions and materials used for the Moxon rectangle, including 6mm diameter aluminum tubing for the elements and a PVC boom. G3XBM notes that the antenna was built for portable use, making it lightweight and easily deployable for field operations. The feedpoint impedance was measured at 50 ohms, ensuring a direct match without the need for an external tuner, which simplifies setup. Performance tests included comparisons against a commercial 5-element Yagi, revealing that the Moxon provided comparable forward gain and an excellent front-to-back ratio, crucial for reducing local QRM. The author's observations confirm the Moxon's reputation as a robust performer for its size, suitable for both fixed and portable 70cm operations.

The ultimate Keyhole Markup Language (KML) plugin for Google earth. Keyhole Radio is a unique and powerful RF planning interface, accessed by loading a Keyhole Markup Language (KML) overlay in Google earth.

Club dedicated to the world of Hellschreiber

The problem with making your own trapped HF antennas is usually getting the coaxial traps tuned to frequency.

The HF ham bands can be mysterious. Some work at night, some during the day. Some seem to be good for long distance contacts while some are better for nearby contacts. Even worse, they change tremendously from hour to hour and day to day. An overview on operating on HF amateur radio bands

An easy mod to make the 1st IF of the Icom IC-7600 accessible and connect to a cheap RTL SDR dongle by VE4NSA

Lighting protection document by Glen E. Zook

Sometimes amateurs like to home-brew their power supplies instead of purchasing one off the shelf at any of the major ham radio retail dealers.

CWQSO allows you to practice sending and receiving CW in a real QSO!

An Arduino project to make it work as a KISS TNC

Constructing a portable, high-gain antenna for _AO-40_ satellite operations presents unique challenges, particularly regarding mechanical stability and parabolic accuracy. This resource details the build of a 1.2-meter "brolly dish" antenna, utilizing a non-conducting fiberglass umbrella frame as its foundation. The project outlines a method for achieving a parabolic shape using stressed aluminum fly screen mesh, guided by practical geometry and a temporary dowel template. Key steps include selecting an appropriate umbrella with a suitable f/D ratio (ideally >0.25), removing the original fabric, and precisely cutting and attaching eight segments of fly screen to the struts to form the reflective surface. The construction process, which took approximately five hours for the author, _G6LVB_, resulted in a dish with an f/D of 0.27 (depth=270mm, diameter=1160mm, f=310mm). The article also describes a modification to a _TransSystem AIDC_ feed, incorporating a PCB reflector behind the dipole for easier mounting. Performance tests at a squint angle of 15 deg and a range of 50,000km yielded a signal-to-noise ratio of 33dB on the S2 beacon and 23dB for SSB signals, indicating strong reception. The author notes that the modified umbrella may not close fully without risking surface disfigurement.

A Half wave antenna has a high impedance feed point. This can be matched using a 1/4 wave stub matching section and converts the 40m vertical into an L-shaped 20m J-Pole antenna. The 300 ohm feeder used for this purpose must be kept away from the ground.

An inexpensive condenser microphone with excellent performance can be easily constructed with easily available parts.

A project of a semi vertical trap antenna that can be tuned for 7 bands

A PDF File to download and print, with a table of all menu options with values, default settings, description and a quick reference guide of the front panel menus

The DL2NBY Contest Calendar, leveraging the Google Calendar system, presents approximately 400 **HF amateur radio contests**, detailing their dates and rules. It covers a broad spectrum of operating modes, including CW, SSB, and various digital modes like RTTY. The calendar integrates contest information from major organizations such as ARRL and DARC, providing a centralized repository for contest operators. This resource offers the capability to integrate contest events directly into a user's personal Google Calendar, streamlining contest planning. It functions as a comprehensive schedule, allowing operators to review upcoming events and prepare for participation across different bands and modes. The calendar's structure facilitates quick access to contest specifics, aiding in strategic contest operation.

The SARK100 Antenna Analyzer it is yet another antenna analyzer but available in kit form and designed to be easy to assemble and with an affordable pricing.

Original article published on February 1992 on 73 Amateur Radio Today about the 2m and 70 cm copper cactus J-pole antenna

A means of sync-ing your computer clock using a GPS Receiver. GPS2Time is another GPS network time synchronization software application for Window 7 and higher. Freeware.

The resource details the construction of a 6-meter _Moxon_ antenna, presenting two distinct versions: one horizontally polarized for 50-51 MHz CW/SSB and another vertically polarized for 52-54 MHz FM. It specifies the use of 5/8 inch OD and 1/2 inch OD aluminum tubing, with 3/8 inch OD solid aluminum for corners, and provides a comprehensive material cutting schedule. The design aims for robust, portable construction, with all materials costing under $100. Detailed drawings and EZNEC models are referenced for precise dimensions and assembly, ensuring accurate element spacing and impedance matching. The EZNEC model for the H-POL version predicts a gain of **11 dBi** and a front-to-back ratio of **25 dB** at 50.5 MHz, while the V-POL version shows a gain of **6.7 dBi** and a front-to-back ratio of **36 dB** at 53 MHz. The article includes practical SWR measurement advice, noting the impact of coax length and loss on analyzer readings. Field tests during a tropical storm demonstrated the antenna's durability and performance, yielding numerous contacts across significant distances, including California, Colorado, and Texas, on SSB and PSK.

How to Increase your CW speed article by George Allison, K1IG as published on QST

This resource, "Transistor Audio Preamplifier Circuits," offers comprehensive design guidelines for constructing **bipolar transistor** audio preamplifiers. It delves into critical aspects such as quiescent current setting, voltage gain calculation, and the impact of various component choices on circuit performance. The content provides several _schematic diagrams_ illustrating different preamplifier configurations, including single-stage common emitter and two-stage designs, alongside explanations of their operational characteristics and practical implementation considerations. The analysis extends to frequency response, noise performance, and distortion, providing insights into optimizing these parameters for specific audio applications. The resource presents calculated gain figures for various stages, demonstrating how to achieve desired amplification levels. It also discusses the importance of proper power supply decoupling and input/output impedance matching, crucial for integrating these preamplifiers into larger audio systems or ham radio transceivers. The practical application of these designs is evident in their suitability for microphone preamplifiers or general-purpose audio amplification.