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An easy to build single wire antenna for 160 and 80 meters with a better than 2 to 1 swr across the 80 meter band

Illustrates the specific wiring and configuration steps required to interface an SGC-230 Smartuner with an Icom IC-706 HF/VHF/UHF transceiver. The document details the necessary connections for power, control, and RF signal paths between the two devices, ensuring proper impedance matching and automatic antenna tuning functionality. It specifies the pin assignments for the IC-706's ACC socket and the SGC-230's control port, crucial for successful integration. Outlines the operational considerations for the combined system, including initial setup procedures and potential troubleshooting tips for common connectivity issues. The resource presents a clear, diagrammatic representation of the interconnections, which aids in visual comprehension of the required cable fabrication or modification. Covers the specific settings within the IC-706 menu that need adjustment to enable external tuner control, such as the 'TUNER' function and other relevant parameters. This ensures the transceiver correctly communicates with the SGC-230 for efficient antenna tuning across various amateur bands.

This is a popular antenna design as the performance is very good across the HF bands and requires little or no tuning. It is a dipole fed off center with a 4:1 current balun at the offset feedpoint. The antenna shown covers 80, 40, 20 and 10 meters with 15 meters and WARC bands

Circuit of the Kenwood IF-10D interface for the TS-50 transceiver.

Power supply from 3 to 30 V with an L200 IC by dl5dbm

CW decoder project that automatically adapts itself to the CW rate and may be employed for learning purpose substituting the traditional tone generator and offering the capability of displaying the keyed code.

The AMRAD Active LF Antenna. You can tune into LF activity with this easy-tobuild and erect active antenna. As a bonus, you get MF and HF coverage, to not to mention world-class performance

This attenuator is worth your attention. Built like the proverbial brick outhouse, it's one you can easily duplicate by N9SFX Pdf file

Make yourself a Diplexer

D-star technical requirements and documentation

A Comprehensive roundup of the most popular QRP transceiver kits on the market in recent years in PDF format

A different approach can help you optimize attic-bound aerial by W6HPH

DF9CY Active Magnetic Antenna project

A monoband end-fed half wave for 10m, 20m or any other HF band, includes a PDF with detailed information to build your own monoband or multiband antenna

K9AY receiving antennas for PA6Z made by PA9M

Amateur Prefix Maps by UT0UM updated with ARRL DXCC and ITU changes, available for download in PDF

High speed silicn diodes work well as RF switches. This article describes how to use diodes for selecting two or more filters ARRL QST article by W1FB

VU2VWN project to homebrew a CW for 40 meters band

The Classic Multiband Dipole Antenna QST article. The open-wire feed line dipole antenna is easy to install and offers surprising performance on several bands. You can install it in almost any configuration; it does not have to be strung in the traditional horizontal flat top

A circuit that connects an IBM compatible personal computer, running TR Log or CT (etc.) contest logging software, and Kenwood transceivers equipped with serial control ports. CW keying is also provided in this RFI filtered interface unit.

Simple, low cost interface between Kenwood serial ports and contest logging programs by Bob Wolbert, K6XX

An interesting and very detailed report analysis of three populare HF+6m transceivers. Yaesu FT-950, ICOM IC-7410 and the Kenwood TS-590S by AB4OJ

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

WAS Map, worked all States by ARRL

Yaesu FT-2000 FT-2000D Cable connections

An RF power supply for 144 MHz schematics and instructions

A portable 4 elements quad antenna for 144 MHz, 9 to 10 DBd forward gain, 30 DB front-to-back ratio, and 33 DB front-to-side ratio

The document details the construction of a compact, two-element Quad antenna specifically designed for the 10, 12, and 15-meter HF bands, featuring a single feedline for all three bands. It provides specific dimensions for the driven element and reflector loops, along with boom length and spacing, emphasizing a **0.12 wavelength** spacing between elements. The design incorporates a gamma match for impedance transformation and uses PVC tubing for spreaders, aiming for a lightweight yet robust structure suitable for portable or restricted-space operations. Performance measurements indicate a forward gain of approximately **6 dBd** on 10 meters and a front-to-back ratio of _20 dB_ on 15 meters, demonstrating effective directivity and signal rejection. The antenna exhibits a VSWR below 1.5:1 across the target bands, achieved through careful tuning of the gamma match. This compact Quad offers a viable directional solution for HF DXing and contesting, particularly where full-size Yagis are impractical.

A pdf file with review of RTTY contests software available on the net and information on how to operate a RTTY Contest, by RSGB.

How to calculate "phasing line" lengths that actually work.

Article on radiation patterns of small loops, equivalent circuits of loop antenna, small loops as receiving antennas, ferrite loops

Schematic for Data, power, CAT, Key and Mic connection interface cable

Excellent poster representing the electromagnetic spectrum from 31.2 mHz to 6.52 EHz, PDF file poster designed by Anthony Tekatch

Deciphering weak or noisy **CW** (Continuous Wave) signals often presents a challenge for amateur radio operators, particularly in contest environments or during DXpeditions. CWLab04X addresses this by providing a software solution that leverages **DSP** (Digital Signal Processing) capabilities of a soundcard to decode Morse code. It functions as both a receiver and a sender, supporting traditional CW and a unique "CCW" mode designed to enhance copyability of signals struggling against high noise floors. The program offers two installation methods: a Windows-specific installer for straightforward setup or a zipped package compatible with Windows and Linux systems running Wine. Users must first download and review the accompanying PDF documentation, CWLab04.pdf and CWLab04_Hardware.pdf, which detail the software's operation and the necessary soundcard interface circuit. The hardware PDF outlines a direct connection from the receiver audio output to the soundcard input, with optional conversion of the soundcard output for hard-keying or microphone input. CWLab04X is intended as an operational aid rather than a replacement for skilled human copy, particularly highlighting the effectiveness of its CCW mode in adverse signal conditions. The software was last revised in April 2009, with installation requiring the LV Runtime 602.

A pdf file with schematics of an ssb and cw filter AF amplifier

Choosing the right antenna for you, by Lewis G. McCoy W1ICP

DG6RBP homebrew project for a USB cable progtamming interface for the Yaesu VX-2 radio

A 5/8 wavelength mobile whip antenna for 2 meters can be constructed from a 5-foot CB helical whip, requiring the removal of original wire and installation of a new radiating element made from coax braid. The design incorporates an 8-turn loading coil with 5mm spacing, fabricated from the original whip wire, and utilizes approximately 1400mm of RG-58 coax braid for the radiating element to enhance flexibility and bandwidth. Final whip length is approximately **1350mm** from base to braid end, with tuning adjustments made by trimming the braid. Dual-wall 12mm heat shrink, such as _Jaycar WH5643_, is recommended for weatherproofing and stabilization, costing around $4.50 per 1200mm length. Achieving a 1.1:1 VSWR may not be feasible; a 1.5:1 VSWR is considered acceptable. Optimal mobile mounting is centered on the vehicle roof to minimize radiation pattern variations.

W3DZZ trapped multi-band antenna, exposed in this practical wireless article

Simple, easy to build, low cost, compact, multiband By Robert Wilson, AL7KK

This article describes a low-cost vector network analyzer that operates from 200 kHz to 100 MHz, and connects to a personal computer using a USB 1.1 interface By Tom McDermott, N5EG, and Karl Ireland

Ari Milano draw and keep updated these pdf files representing the "radioamatori" bandplan, with notes in italian

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.

A complete review of Icom IC-706 review published in 1999 by QST

Comparison of several UHF antennas by DF9CY

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.

This project produces an inexpensive, multiband, end fed HF antenna matchbox, quick and easy to setup. This project creates a trifilar wound, 9:1 UNUN toroid matching transformer. Handles 100W and need an antenna tuner.

Amplifier keying buffer for ICOM radios & others. Suitable for IC-746 IC-756 PRO and PROII. ACC1 key interface by KK5DR

Conversion of Zetagi HP201 SWR wattmeter for HF Amateur Bands by G8ODE

VU3NSH article on high current universal supply for rigs