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A very portable Umbrella Dish for the A0-40 Satellite operation, by G6LVB

A simple antenna analyser for the HF spectrum with a built-in signal generator with 3-digit LED frequency display.

Software for analysis of guyed and self-supporting towers & poles

Software Defined Radio Projects, HF Receivers and Transceivers projects by YU1LM/QRP

The ZS6BKW multi-band antenna, an optimized variant of the classic G5RV, is presented with detailed construction and tuning instructions. This resource outlines the antenna's design principles, which were developed by _Brian Austin (G0GSF)_ using computer programs and Smith charts to achieve optimal dimensions. It provides specific guidance on calculating and adjusting the lengths of the radiators (L1) and the matching ladder line (L2), emphasizing the critical role of velocity factor (VF) in achieving resonance. The article includes a step-by-step procedure for empirically determining the VF of ladder line using an antenna analyzer, ensuring accurate physical lengths for the matching section. It details the tuning process for the radiators, offering practical tips for incremental adjustments to achieve the best SWR curve. The resource presents SWR measurement results obtained with an _AIM-4170C_ analyzer across multiple bands, alongside predicted SWR graphs from an AutoEZ model. It confirms successful contacts on 80, 40, 20, and 17 meters, including a **17-meter DX contact** to Italy. EZNEC and AutoEZ models for the ZS6BKW antenna, covering 80 through 6 meters, are provided for download, allowing further analysis and customization. The document specifies component details, such as the use of Wireman 554 ladder line and #14 AWG THHN copper wire, and discusses the antenna's performance characteristics, noting high SWR on 15 and 30 meters but successful tuning on 6 and 80 meters with an external tuner.

Heathkit Icom Kenwood Power Transistors Ten Tec Yaesu spare Hamradio parts.

A comparison of multiband dipoles, including jumpered dipole versus fan dipole antennas, dipole fed by ladder line, resonant dipoles antennas. ARRL lab notes

Pics and specifications

5000+ member discussion group for the low-cost series of SoftRock SDR receiver and transceiver kits.

Home Page of Ivan, 9H1PI, QRV from the island of Malta on 50 MHz.

A compact 2 element W8JK beam antenna for 20M to 10M bands by AF6SA

Sleeve baluns are normally used at VHF and higher. As a general rule, they are not practical at HF. The balun can be inverted and used as a skirt to form part of the antenna element

Specifiation at rigreference.com about Yaesu VX-8R/E

The RasHAWK team has used a Raspberry Pi as the basis for a networked RF sensor capable of supporting spectrum monitoring, signal intercept and direction finding (DF) operations.

A project for a 50 MHz moxon rectangle antenna

Cabrillo2Adif A software for converting the radio logs from Cabrillo to Adif log format (for Mac OS X)

SSTV, pictures, home brew from sweden

The resource details the construction of a homebrew 50-watt FET amplifier, based on Don W6JL's _QST Homebrew contest_-winning design from 2009. It functions as an afterburner for QRP transceivers, providing a **12dB** power lift. The amplifier utilizes IRFZ24N FETs and covers the 80, 40, 30, and 20-meter bands, with the 20m LPF extending to 17m. Key technical aspects include an FT37-43 transformer for the input network, a relay-switched 3dB pad for lower bands controlled by an _Arduino Nano_, and an RF-actuated T/R switch. The LPF board integrates four relay-switched filters rated for 50 watts, using capacitors with a minimum 250VDC rating. Performance measurements indicate a power gain ranging from **4.4dB** on 20m to 8.1dB on 80m, with a required drive power of approximately 5 watts. The article also discusses thermal management, current limiting considerations, and component sourcing.

A dipole antenna for 7 MHz support for this antenna is fiberglass military mast

Extend the range of wireless network or connect to other wireless networks in neighborhood with your own wifi antenna.

In this PDF article Zack Lau describe how to homebrew a four element yagi beam antenna for 50 MHz band, including how to build mounting blocks and tubing clamps to hold elements.

Why all the mystery surrounding baluns ? To use or not to use baluns

This is an internet resource for those interested in guitar amplifiers, vacuum tubes, and design tools such as SPICE modelling.

A K9AY loop antenna project done with Far Circuits pc boards for the antenna switch and bandpass filter and preamp by K7SFN

Construction of attenuator, suitable for fox hunts at 144mhz

Resources for amateur radio astronomers, teachers, and students.

Flash crystals, Feakin' beacon keyer, beacon attenuator

A Compact and efficient multiband beam antenna based on a Modified W8JK Array by K5LJ

Chart showing how SWR effects how much power you actually radiate from your antenna.

Heathkit Manuals

The Packet Radio beginners guide to packet radio operating by Buck Rogers K4ABT

This page contains a map of Amateur Radio Russian Prefixes.

Amatuer Radio QSL Cards. Full Color QSL and Eyeball Cards

Article on tubes and their usage in power amplifiers design. Explain failures of tube in RF power amplifiers, a common problem in the SB-220 SB-221, TL-922 and other amplifiers.

Your beginner's guide to shortwave radio, include an up to date blog and news about products and events.

Firsts pictures of Icom IC-9100 taken at Tokyo HamFair 2009

The Western Washington DX Club is an organization of Amateur Radio (HAM) operators who have a special interest in DX or distance communications

In his back office section, ON4SKY, initiates in a few articles the beginners in the art of QSLing and award chasing.

A hombrew QRP transceiver for 40 meter band with many pictures, circuit and sound recording of some QSOs made with this Rig consisting of 5 transistor and one chip.

Kenwood TS-450S/TS-690S MARS modification video

A bycicle ham radio station setup, with full band coverage

Manufacturing distributor of infrastructure products for the telecommunications industry; antenna mounts, ice bridge, cable ladder, ground bars, weatherproofing, exothermic, safety equipment.

Sams continues the tradition with the publication of new manuals every month, covering the latest in Televisions, including HDTV, Projections TVs, and coming soon, LCD monitors.

An Offset Attenuator for fox hunts.

Tektronix Oscilloscpe home page, feature tekexpress DSA series products

Hams with web cams database with net and roundtable information.

Learn morse code with morse machine, A Fully Automatic Morse Code Teaching Machine first described in a May 1977 QST. Free for Windows MacOS Linux and DOS

This site serves a community of volunteer and paid professionals in Search & Rescue and Civil Air Patrol who save lives and Amateur Radio enthusiasts who use DF skills as a hobby. We provide antennas and other resources for people in these fields.

How to receive images from orbiting noaa weather satellites using simple receiving equipment and a computer by G4ILO