rf filter

50 MHz Antennas by DF9CY (4 & 6 Element)  ^pop - Two well performing 50 MHz antennas designed with W7EL EZNEC along to many other antenna projects and related articles

Romeo Fox Dx Group USA - Membership Info no cost to join

IOTA EU-110 Log St Nikola Isl - 9A/I2OGV, 9A/I2RFJ, 9A/I2ZBX, 9A/IZ2LSC 2010 dx pedition online log

HF Hamtrader Nes - Trader net frequencies

The Amateur Radio Flea Market - Treffpunkt Amateurfunk (German)

RSGB Region-12 - RSGB Region-12 Website for Cambridgeshire, Bedfordshire, Norfolk, Essex, Kent and Suffolk.

PD2RFU Jeroen - PD2RFU by Jeroen GoedÌl Fox United, Formula 1, Motors, links and all about ham radio

LinkPlus - LinkPlus products enhance the voice quality of HF SSB amateur. Eliminates virtually all channel noise and interference and greatly strengthens SSB radio signals

Array Solutions - WX0B - Stacking and phasing HF and 6m arrays antenna switches and contesting devices. Custom low band antenna arrays, bandpass filters,commercial/Mil STd filters,microwave components, commercial broadcast filters.

Signal Engineering - Signal Engineering technologically advanced antennas with modern design and construction technique. Up to date information about current line of high performance 10 and 11 meters antennas.

Tigertronics, Inc. - Packet/telemetry modems, GPS tracking, sound card interfaces

Tesoel - RF-and Microwave Coaxial switches and relays

Bencher Inc. - Paddles, Keys, Filters, Antennas

Mirage - VHF and VHF amplifiers including repeater rf amplifiers

Vectronics - Antennas, Filters, accessories, wattmeters, tuners and amplifiers.

Current Aurora status - The Aurora in near real-time from Sweden

The Sunspot Cycle - Sunspot Numbers, The Butterfly Diagram, the Greenwich sunspot data and sunspot realted infos.

National Weather Service - Some little known facts about the NOAA Weather Radio system

Radioman - Freeware dos VHF/UHF Logbook morse code facility, kenwood transceivers interface, moontracking, distance and bearing calculators by DF9CY but discontinued and unsupported

CwGet  ^{updated  pop} Priority listing - A program to decode morse code (CW) via sound card to text. It can work as narrow-band sound DSP-filter also. No additional hardware required — you need only receiver and computer with a sound card. Can integrate with AALog logger.

AREPS propagation programs - Collection of various propagation software by Space and Naval Warfare Systems Center, San Diego, Atmospheric Propagation Branch

RF prop  ^pop - RF propagation software

TH-D7 control program - This software allows you to control TH-D7 radio functions in real time, using a windows interface. This software will graph current activity of any 4mhz range, allowing the user to mouse click any active portion - automatically changing the radios frequency.

Tunekit - Filter Tuning Kit for Windows is a electronic filter synthesis program and a practical filter tuning aid for actually designing and building a working filter

TVI and BCI Filters - TVI and BCI bandpass and bandstop filters in SMD technique. Schematics and images.