valve design

KN4LF Antennas - Antenna design and LW, MW, SW and Amateur Radio dx'ing.

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

Reflected W Beam - Hexagonal Wire Beams for 40-10m from DL7IO, different mono/multiband designs with building descriptions and model files for EZNEC

1270Mhz Yagi Antenna - Build your own antenna for the 23cm band ( 1250Mhz - 1280Mc ) using some aluminium and this simple design.

OH2GI Ham System - All-mode contesting and logging software system designed primarily for on-line operation of HF digital and CW radio stations through Terminal Node Controllers (TNC)

Pacific IOTA Numbers - IOTA Designation for The Hawaiian Islands

Matt's Media Network - 5 Webcams, SWL info, Top 100 shortwave sites, Webcam Mania Top 100, Matt's Banner Exchange.

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.

KMA Antennas - KMA Antennas specializes in HF - VHF - UHF Log Periodic Antennas, unique antennas for the Six Meter band and custom antenna designs.

Q-PAR Microwave Antennas - The company (founded in 1973) excels in the research, design, development and manufacture of microwave antenna systems & components. Our range includes horn, reflector, sinuous, spiral, LPDA, helical antennas, etc; antenna positioners, and many bespoke components.

Piccon - PicCon is a PIC microcontroller based radio controller designed for hidden transmitter hunting

HD Communications - Rf Connectors,RF Amplifiers,RF Filters,HF cable and accesories. Tower hardware valves and tubes

Broadcast microwave services - Designs and manufactures a comprehensive line of microwave communications equipment for television broadcast, video, telemetry, and electronic surveillance applications.

Valve radios - Viking SW design and produce valve (tube) receivers for the ham and SWL.

Bird Electronic - Design and manufacture of components, instruments and systems for RF power measurement.

Camellia Trophy Shop - Custom Engraved QSLs, Designed On-Line

PolarPlot - Freeware antenna software that lets you see what the polar diagram of your rotatable beam actually looks like where it is operating. With PolarPlot you can measure the polar diagram of the antenna and check for abnormalities - compare plots taken before and after changes to the design or location - check the -3dB beamwidth - look at the front to back ratio - see the size and position of the sidelobes.

QARTest - Italian only contest logging software, designed for the ARI 40-80 contest.

Spectran - Program designed to do spectral analysis and real-time audio filtering on reception of audio signals for EME, VLF, SETI applications. Offer support for MTHELL, QRSS, DFCW, NDB, WSJT by I2PHD

VHF-DX - VHF-DX for Win95/98 is a VHF/UHF Logging Program specifically designed for 50MHz and above operation.

Int. Morse Code program information - This program is designed to help the beginner learn to receive and send the International Morse Code.

Amplifier Simulation Program - ASP 4.0 - Design weak signal GaAs FET or bipolar PreAmps. Automatically designs for optimum gain, NF, VSWR or all.

Satfax - Satellite weather decoding software, designed for those weather monitors who use their ICOM R7000, ICOM R7100 or AOR 3000A

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

KI5YN QLF Filter - The QLF filter is a microprocessor based interface designed to go between a standard Morse code key and a radio transmitter