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A trifilar folded dipole antenna for 80 meters band

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

Mast systems and antenna accessories, hamrope(R) guy lines by Jurgen Simon DH5AB

A moxon antenna project for the 145 MHz

Modifications and messages about the Yaesu FT-450

A vertical antenna that can cover HF bands using an UN UN and a fishing pole, usage of tuner is requested.

A 500-watt mobile antenna project details the conversion of an old 10m hamstick into a highly efficient, multiband "bugstick" for HF operation. The core modification involves replacing the original coil with 25 turns of 6 turns-per-inch, 1.5-inch diameter coil stock, fabricated from #14 wire. This design, intended for a 3-magnet mount on a vehicle cab, achieves resonance on multiple bands by shorting out specific turns on the coil, similar to a **bugcatcher** antenna. Measurements taken with an MFJ-259 analyzer on a GMC pickup show 0 turns shorted for 20 meters (14.2 MHz), 10 turns for 17 meters, 16 turns for 15 meters, 19 turns for 12 meters, and 23 turns for 10 meters. The construction emphasizes using UV-resistant tie-wraps and #14 solid wire with crimp lugs for robust RF connections, bypassing the fiberglass rod for current flow. A bonus section details a 40-meter version, utilizing 48 turns of 8 TPI, 2-inch diameter coil stock.

Welcome to Mike's radio collection, I collect and restore radio sets from the 1930's to the 1960's. I have built up quite a Collection of radios over the years, including Some rare Dutch and German sets.

QRP and Electronic Kits manufacturer

Getting started with RTLSDR on MacOSX

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

Excellent slides explaining radio and radiowaves generation basics

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

Construction details and tests about a 2 elements cubical quad antenna for HF Bands (20,17,15,12 and 10m band).

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

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

This is a packet radio software developed for amateur radio operators to provide IP communications. You can chat, send/receive e-mail, surf the web and so on via radio depending on your bandwidth. You don't need a TNC. You might have all of TNC features via SoundCard using SoundModem.

Data Management for the RadioShack PRO-93/2053 Trunking Scanner

Yaesu Icom Kenwood CAT Interfaces. Isolated audio-DATA interfaces for ALL afsk DATA modes inc psk31 rtty sstv etc.

A ground plane antenna for 80 meters band

Take the mystery and mystique out of standing wave ratio. QST Article by K5DVW

WV7U's YC156 and 3CPX800 amplifier projects. Everything you wanted to know about using the YC156 or 3CPX800 in a ham radio linear amplifier. See pictures, schematics, test data, links, and more!

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

Announce your callsign at least once every ten minutes. HamTime runs in the corner of the screen and gives you an audible alarm when that announcement is due.

Expert Electronics LLC is a manufacturer of modern and compact SDR transceivers. EE develops and produces modern radio-electronic devices based on SDR (Software Defined Radio) for radioamateurs and professional applications. Makers of popular SunSDR models and SunSDR-MB1 transceivers

The Icom IC-746 is quite a popular HF/VHF multimode transceiver which has one shortcoming in its standard configuration when used to operate modes requiring good medium-term frequency stability.

Ram mounting systems is a world leader for design and manufacturing of mounting applications. ram mounts offer more than 900 interchangeable components for unlimited uses and configurations.

A freeware apple Macintosh-based program that helps amateur radio contesters by converting a log from a radio contest into the Cabrillo file format which may be submitted to the contest sponsor.

British based CW club, originally founded in 1938

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

Technical details of the yaesu FT 9000

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

International Components Corporation has an extensive range of electronic components consisting of audible signal devices, speakers, microphones, capacitors, electron tubes, connectors, and accessories designed in recognition of the diversity of applications and special characteristics encountered by designers in today's complex world.

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

Near Vertical Incidence Skywave (NVIS) and the 40 meter Novice Sub-band.

A moxon anetenna plan for 144 MHz

These instructions use simple, generally familiar examples of equipment types and are designed to help you find the adjustment that suits you best. If you are looking on how to adjust a morse key, bencher key, paddle or straight morse key, here you will find all instructions.

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.

Flash Movie describing HF (shortwave) radio propagation to beginners. Very helpful aid in understanding.

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.

It is a application which can be used for troubleshooting CB radio faults, by giving a graphical display of the normal operating frequencies generated by various parts of the CB radios circuits, it can help you identify if a frequency is incorrect or even missing. Another good use for this software is simulating possible frequency expansions, as it allows you to choose any frequency that the PLL is capable of generating, so you can see what the radio will allow you to get !

Shortwave Radio Schedules from Eibi/AOKI combined lists. Includes Google maps showing beam directions and long paths.

An end-fed halfwave antenna for 20 meters band with balun pictures and description by PD7MAA

F5AD describes the ATV repeaters in the south of France, and methods, frequencies, modulations used in ATV in France and in Europ. (French and English)

TinySDR for 80m band and ZetaSDR for 40m band

Listen online to NYPD Special Operations Division live radio audio feed.

W4KAZ article on antenna switches

Since February 2002, 3830scores.com has served as a central repository for amateur radio contest score rumors, allowing contesters to quickly post and view claimed scores and comments. The platform facilitates the sharing of **claimed scores** for numerous contests, including the ARRL DX Contest, CQ WPX RTTY Contest, and various QSO Parties. Users can access submittal forms for current and recent contests, with options to define and save default form values for efficiency. The site also provides links to the 3830 Reflector, where submissions are posted, fostering immediate community engagement regarding contest performance. Summaries of all submitted scores are instantly available, offering line scores, **band/mode breakdowns**, and compilations of operator comments. Historical summaries for major contests extend back to 2002, with all contest data accessible from 2007. The platform includes a search function to locate all postings associated with a specific call sign and a 'Compare Scores' feature, enabling side-by-side analysis of multiple calls across different contest editions or a single call's performance over several years.

Codec2, an open-source speech codec, targets low bit rate voice communication, specifically designed for digital radio applications operating within constrained bandwidths. The project focuses on achieving intelligible speech quality at data rates around 2400 bits per second, a critical parameter for efficient spectrum utilization in amateur radio. Its development addresses the need for robust voice transmission over channels where higher bit rate codecs would be impractical or inefficient. The resource details the technical specifications and implementation aspects of Codec2, including its underlying algorithms and performance characteristics. It provides insights into how the codec processes speech to achieve its low bit rate, outlining the various coding schemes and their impact on voice fidelity and error resilience. The information presented allows radio amateurs and developers to understand the codec's operational principles and its suitability for integration into custom digital communication systems. Applications for Codec2 extend to digital voice modes on HF and VHF bands, enabling more users to share limited spectrum resources. The project's open-source nature facilitates community contributions and widespread adoption, fostering innovation in digital amateur radio. It represents a significant effort to provide a freely available, high-performance speech coding solution for the amateur radio community.