rf circuits

Antennas : theory and designs - Thierry LOMBRY, ON4SKY, develops in several long articles all you need to know about antennas, their design and performance, for both amateurs and SWL

Oscar Kilo Dx Group - 11m radio Oscar Kilo dx group HQ based central Uk

RadioQTH - Ham radio vanity license search - RadioQTH Amateur Radio Vanity License Search: This site shows vanity call sign requests filed with the FCC, when call signs will be available for vanity applications and other useful tools that will help in the search for the perfect amateur radio vanity call sign.

All about Lightning protection - Thierry LOMBRY, ON4SKY, gives advice to amateurs about lightning protection of an hamshack, including pictures and links.

Blackford County, Indiana Live Scanner feed - Blackford and surrounding counties Police, Fire, EMS, and EMA.

Radio Audio and sound files - Some tens of very special audio files recorded during amateur radio activities like aurora traffic, meteor scatter, communications with ISS crew and the sound of various transmission modes that you can hear on HF and VHF bands

ARTRA QRP Kits - Lots of homebrew kits, you can buy kits or download as free, Association des Réalisation et Techniques RadioAmateurs. Transceivers, filters, converters, frequency meters, antenna analyzers, ATV receivers, interfaces

PROCOM Antennas - Manufacturer of communications antennas, bandpass filters, RF combiners, receiver multicouplers, diplexers, duplexers, RF connectors, RF circulators, RF isolators, RF couplers and SWR meters

Gizmotchy Antennas - The Charles Gizmotchy high performance horizontal and vertical beam antennas. Two, Six, Ten and eleven meters antennas

MixW RigExpert - USB INterface - MixW RigExpert integrates sound card with CAT, PTT, CW and FSK functions in a single box with USB connection to your desktop or notebook computer for operating phone, CW, and digital modes.

TestInHouse - Manufacturer of RF Shielded boxes, RF shielded enclosures, test accessories for wireless phones and handhelds testing. RF and Audio test solutions. GSM, CDMA, BlueTooth, Wi-fi test.

QRP LABS - The QRPLABS series of single band QRP CW tranceiver kits are high performance CW tranceivers with easy operating features, small size and light weight.

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

How to select an amplifier - Thierry LOMBRY, ON4SKY, develops in three long articles all you need to know about amplification, and how to seletc an HF and a solid-state amplifier, with pictures.

How to select a transceiver - Thierry LOMBRY, ON4SKY, develops in several technical articles the way to select a transceiver. His website includes also some in-depth reviews

The History of amateur radio from 900BC to date - Thierry LOMBRY, ON4SKY, develops in depth and with original pictures the long history of amateur radio all through the world from 900 BC to date.

Basics of Propagation by ON4SKY - Thierry LOMBRY, ON4SKY, develops in several long articles the bascis of propagation. His website includes also a French section dealing with auroras.

Giles SkyWarn - Giles SkyWarn KI4CFK is an ARRL affiliated club dedicated to preparedness in case of severe weather or any emergency which requires emergency communications on 146.775

Eurofrequence Dierking in Germany - Accessories, like universal audiofilter, Mixer interface for sound card, highvoltage powersupply, accessories for 706, hamradio vacation,Roger Beep, Microphons, Headsets and more. Please look

AEA - Wireless software - AEA Wireless Director Software Series turns PC's (running Windows 95/98/2000/ME or NT) into powerful tools that expand the use and power of SWR, Return Loss and Complex Impedance Analyzers.

AZMap - Azimuthal maps generator - AZMap is a freeware Windows program for the Windows PC which will generate, display, and print an Azimuthal-Equidistance (A-E) map of the world, centered at any point on the surface of the earth (except very near the poles). The A-E map is also known as a Great Circle map since straight lines from the center point to any other point always fall along a great circle path and represent the shortest distance between the center and that point

SIGVIEW spectrum analyzer - Complete real time signal analysis software with wide range of powerful FFT spectral analysis tools, statistics functions and comprehensive visualization system.

Ferrite information - Ferrite Toroidal Cores, Magnetic Properties of Ferrite Materials, EMI - RFI Suppression Design Considerations, Ferrite Beads, Ferrites for RFI Ferrite Cores for RFI Suppression by CWS ByteMark

K8TM Articles - This publications page lists articles on surface mount devices, amateur radio, soldering, shunts, and measuring large direct currents.

Interference Handbook - Interference to home electronic equipment is a frustrating problem; but, fortunately, there are several ways to deal with it. This handbook provides a step-by-step process for eliminating the interference