websdr app

The Crossed-Field Antenna - Please be aware this article introduces a completely new concept in antenna theory. In fact, this is considered the most important development relative to antennas in this century. It is so pervasive that a series of articles are required to cover the concept and its applications to the depth and extent it deserves. This is the first publication about the Crossed-Field Antenna

2.4 Ghz double quad antenna - An easy to build, compact antenna for wireless lan applications that offers a reasonable amount gain.

Multi-pitch Helical Antenna - Creating multiple, overlapping resonance at 700-800 MHz band and leaving the VHF part of the response as in ordinary, narrow band helical antenna.

Helical Feed Antennas - Helical antennas have long been popular in applications from VHF to microwaves requiring circular polarization, since they have the unique property of naturally providing circularly polarized radiation. Paul Wade W1GHZ

Helical/helix antenna 2.4 GHz HOWTO - Helical/helix antenna cookbook recipe for 2.4 GHz wavelans and/or WiFi applications

Loop Antennas and Calculator - The purpose of the calculator is to give you a quick overview of the feasibility of "squeezing" a loop into your available yard or apartment space. The calculator yields a reasonable approximation of dimensions, to within 5% over the amateur bands, using typical wire gauges ranging from 12-18 AWG.

Trapped antennas - ARRL index of document about trapped antennas and notes on traps usage

TrapDip - This program let you design and performance of 2-band trapped dipole antennas including trap design.

Portable Wire Antenna - W4ZT used this antenna for Field Day and other portable applications. He built them for all bands between 160 meters and 6 meters. You can make them easily using whatever wire you have available and make the insulators from scrap plastic

Colorado QSO Party - After some years of absence the Colorado QSO Party (COQP) is going to happen again. Mark you calendar, tune up your rig and point your antenna toward the Central Rocky Mountains and get ready for a fun time.

K6BJ - Santa Cruz Co. Amateur Radio Club - The santa cruz county amateur radio club. activities, the newsletter short skip, events, links and other happenings about amateur radio.

W1MX The MIT Radio Society - The MIT Radio Society is a student run organization intended for MIT students, faculty, and staff. New student members are greatly appreciated.

Franklin County Amateur Radio Club - FCARC exemplifies the principles of amateur radio: public service, particularly in emergency communications support; growth in our technical skills, and enhancing the application of those skills

Norwood Amateur Radio Club - NARC is an ARRL affiliated amateur radio club located in Norwood, Massachusetts, USA. Approximately 20 miles south of Boston

W2AE Radio Amateurs of Greater Syracuse - The RAGS web site filled with information about the club and its happenings, as well as other ham info in the Syracuse area NY

UK Repeaters for iPhone - UK Repeaters is an iPhone app that shows all UK Based repeaters on a map. Each repeater information is shown to allow easy access and programming of your radio

ICOM 746 Temperature Measurements - The ICOM 746-Pro has acquired a history of NEC 1678G (IC-151) MMIC and driver transistor 2SK2975 failures. The failure of IC-151 appears to be a combination of ESD damage from electrostatic charge on the antenna entering IC-151, and perhaps thermal heat.

Zplots - Excel application that allows you to plot impedance and related data obtained from a variety of sources. You can plot on both an XY chart and a Smith chart as well as view the data in tabular format by AC6LA

AutoRec - AutoRec is windows freeware time based automatic recorder - player for radio broadcast. Auto Recorder will record or play wav audio files, and execute batch or other executable application programs at scheduled times. The primary use for Auto Recorder is automatic, unattended recording and playback of network or other satellite-delivered radio station program material.

cocoaModem - CocoaModem is an opensource MacOS X 10.4 application which implements modems (modulator-demodulators) for RTTY PSK MFSK Hellschreiber CW SITOR HF-FAX provided by W7AY

Spot - Intelligent DXCluster Client - Reliable amateur radio software for OS X and Windows that works the way you expect. Spot allows you to chase the DX that really matters by putting you in charge of which DX spots you need to see and alarming you when they appear.

Fldigi - Freeware Digital modem program for Linux, Free-BSD, OS X, Windows XP, W2K, and Vista. Support several modes and is fully multi platform application by W1HKJ

Codec 2 - Codec2 is an open source low bit rate speech codec designed for communications quality speech at around 2400 bit/s. Applications include low bandwidth HF/VHF digital radio.

Universal QRP Transmitter - Here's the homebrew Universal QRP transmitter adapted from work by Wes Hayward - W7ZOI. The circuit originally appeared in QRP Classics published in 1980 by the ARRL

How to make a Q meter - This article appeared in the February issue of Amateur Radio and is reprinted here for the convenience of others