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A simple TRAP-dipole project for 20 and 40m bands includes EZNec simulations

Generic PI4 + CW + Carrier Arduino Beacon Controller with interfacing to Analog Devices AD9833 DDS AD9850 DDS, AD9851 DDS, AD9912 DDS , AD9913 DDS, ADF4350 and ADF4351 synthesizers, ADF5355 synthesizer, ADF5356 synthesizer, Radio modulated by an audio soft-DDS Reverse DDS, RDDS microwave unit, Silicon Labs Si5351A programmable clock generator, Silicon Labs Si570 programmable XO/VCXO, Texas Instruments LMX2541 synthesizer

We are a group of Amateur Radio Operators who travel around the country in Recreational Vehicles and host radio nets to keep in touch with one another

A new weak signal DX mode for Radio Amateurs, employing M-ary FSK, phase continous tones and convolutional coded FEC.

A triband VHF Yagi antenna for 6 m, 4 m and 2 m with one feed-point by DK7ZB

DK7ZB provides detailed construction plans for Moxon antennas utilizing tapered aluminum tubing, specifically outlining dimensions for 50 MHz, 28 MHz, 24 MHz, and 21 MHz bands. The resource emphasizes maintaining specific taper lengths for optimal performance and describes a tuning method involving symmetrical element shifts. It also addresses stacking considerations, noting that two Moxons can be stacked 1m apart with a 90° rotation to avoid severe detuning, unlike co-planar mounting. Performance figures for the 50-MHz Moxon include a gain of **4.1 dBd** and a front-to-back ratio of _30 dB_. The construction utilizes copper fittings for element connections, with a recommendation to varnish edges against corrosion. The page features images of built antennas by _DK8UH_ and VK2QO, illustrating practical implementations for the 6-meter and 10-meter bands, respectively.

Two types of multi-functional Home-brew 6/8Amps - 20 Ampere variable power supplies by ON6MU

The Old Tube Radio Network is dedicated to those real, American-Made, Old Tube CB Radios

By Alfred T Yerger II WA2EHI, in this PDF file explain how to remote your rig via the internet by using HRD Ham Radio Deluxe and skype

Robert Norgards KL7FM's, notes on upgrading the Heathkit SB-200

The document provides a detailed guide on modifying an inverted-L antenna to include the 160 meters band. This enhancement allows amateur radio operators to utilize the lower frequency effectively, which is crucial for long-distance communication, especially during the night. The inverted-L design is popular due to its compact size and ease of installation, making it suitable for various environments. By adding top band capabilities, operators can engage in DXing and contesting on 160m, expanding their operational range and opportunities. The guide includes practical tips and considerations for construction, ensuring that the antenna maintains its performance across the extended frequency range. It discusses the necessary adjustments and materials required for the modification, along with potential challenges and solutions. Whether you are a seasoned operator or a beginner, this project can enhance your station's capabilities, allowing for more versatile operations and improved signal quality on the 160m band.

March Paddle by K4QU

Circuit diagrams drake tr7, Schaltbilder Drake Tr7, antenna tuners, baluns, and home brew power supplies, dual tone ssb test generator, zweiton ssb test generator, zweiton testgenerator, dual tone test generator by DK4DDS

IK0WRB CW Keyer using a PIC 16F84

A magnetic loop antenna using a 28\" bicycle rim for six meter band

Frank Donavan, W3LPL , discusses beverages on the CQ-Contest reflector. This is a reprint of Frank's message.

A super-fast PSK mode for RTTY Contesting, 100 wpm character transmission speed for contest exchanges and macro transmission versus RTTY at 60 wpm

This free program displays the location of any locator on a map. It calaculates between two Maidenhead locators the distance (km and miles) azimuth longitude latitude Show the location, direction and distance as you move your mouse on a map! Graphical Locator Program, By ON6MU

G3WZT design for a bi-polar 600W Linear Power Amplifier for the 6M band.

A light and portable magnetic loop antenna with improved bandwidth and performance by HB9MTN

The Skeleton Slot Antenna Revisited by Bobby Brainwave, N3VGS PDF File.

DX Finder presents a real-time DX cluster service tailored for amateur radio operators engaged in DX chasing and contesting. The platform aggregates DX spots, Reverse Beacon Network (RBN) data, and PSK Reporter information, displaying current activity across various amateur bands. It provides a centralized interface for monitoring propagation conditions and identifying rare DX entities, aiding operators in making timely contacts. The service integrates multiple data streams to offer a comprehensive view of global amateur radio activity. Users can access real-time spotting data, which includes callsigns, frequencies, modes, and signal reports, facilitating efficient station operation. The inclusion of RBN and PSK Reporter data enhances situational awareness, allowing operators to assess band openings and signal paths more effectively. DX Finder supports both web and Telnet access, catering to different operational preferences. It also features a dedicated JOTA cluster, specifically designed to support the Jamboree On The Air event.

Amateur Radio website with links to radio, IT and the Arts and a link to my Yahoo VHF-CW Reflector.

A ground plane antenna for 80 meters band

picture and dimensions of a coax loop antenna centered at 51.490 MHz

Overvoltage protection, Voltage stabilization, Grounding in wiring, Ground wire resistance

conversion of low band VHF Philips FM-92E to 6 metres

NetTime is a simple and free software to sync your computer clock via internet. Very useful tool for FT8 FT4 operating modes.

The Middle Tennessee Amateur Radio Society is composed of Hams in Middle Tennessee who are dedicated to promoting Amateur Radio, providing public service communications, and having FUN doing so.

A dual band wire antenna project in Italian

Yagi-logper is a linux GPL program to model a Yagi or Log-periodic antennas with horizontal cylindrical dipoles.

Demonstrates the design principles and performance characteristics of **corner reflector antennas**, emphasizing their high gain and directional properties. It covers critical design factors such as the corner angle and the spacing between the radiating dipole and the reflector vertex. The resource explains how reducing the corner angle increases gain but lowers feed impedance, making matching more challenging. Practical angles of 90 degrees or 60 degrees are discussed, with 90 degrees offering easier impedance matching despite slightly lower gain. Details key design considerations, including reflector side length exceeding two wavelengths and reflector width greater than one wavelength for a half-wave radiator. It specifies reflector construction using wire netting, sheet metal, or parallel metal spines spaced less than 0.1 wavelength. The article provides a table with general dimensions for UHF and VHF bands, noting typical impedance values of 50 to 75 ohms and expected SWR of 1.7:1 on the lower band edge. Adjustable radiator-to-vertex spacing is highlighted as crucial for final tuning.

ACOM 1000 modification uses electric band switching, such that both 6m and 4m operation can be maintained.

Links to US local emergency service local units

This homebrew six-meter linear amplifier started off life as a "junker" Alpha 76PA h.f. amplfier. Power output is 800W

W0RW article that guide you to using beacons to determine dead bands or upcoming propagation openings.

My Version of Wes Hayward W7ZOI / Terry White K7TAU Spectrum Analyzer

A microphone preamplifier schematic for hand-helds by ON6MU

Contest, Antennas, Rotating Towers, Rotors, Guywires, CoaxHardlines, Specs and more

cocoaNEC 2.0 is an opensource Mac OS X application intended primarily for the design and modeling of antennas by Kok Chen, W7AY

January 1955 QST article by W5DQV about constructing a Cubical Quad antenna for 14MHz PDF File

RADIOING eEngineer RFI EMI information

Over 1,000 stations in approximately 60 countries were worked using this modified twin-lead folded dipole, demonstrating its effectiveness with just 4 watts on 20 meters. This design, adapted from an ARRL Handbook concept, eliminates the shorting strap found in traditional folded dipoles, simplifying construction while maintaining performance. It utilizes readily available 300-ohm TV antenna feeder ribbon, making it a cost-effective solution for radio amateurs. The antenna's robust construction allows it to handle up to 100 watts without issues, even without a **balun**. The inclusion of a variable trimmer capacitor at the stub provides flexibility for tuning across different frequencies within a band, a practical feature for operators using transceivers like the Icom 735. Formulas are provided to calculate the precise dimensions for any desired operating frequency, enabling customization for various **HF bands**.

a PREDICT client application written by Vittorio Benvenuti, I3VFJ, allows operation of an ICOM PCR 1000 receiver in a satellite communication environmenta PREDICT client application written by Vittorio Benvenuti, I3VFJ, allows operation of an ICOM PCR 1000 receiver in a satellite communication environmenta PREDICT client application written by Vittorio Benvenuti, I3VFJ, allows operation of an ICOM PCR 1000 receiver in a satellite communication environment

Ameritron Al-811H Tuning for Power/Dissipation/Linearity, and More Generally 811A Tube Amps in Grounded Grid

FAR Circuits is exclusively a manufacturer of Printed Circuit Boards for electronic projects that are used by the Amateur Radio and electronic hobby enthusias

Alan yates vk2zay's ham radio website, homebrew construction, general electronics, high voltage experiments, amateur rocketry, and general geek stuff

14MHz SSB 10mW transceiver by JF1OZL

Fox hunting site with details of a PC based DF system

An RF power Amplifier for HF bands with 3 GI-7B tubes by CT1FMS