rf toroid

The Impact of Current Distribution on Array Patterns - Technical Correspondence, QST, July 1990 - Why even "perfect" phased array element currents don't produce perfect patterns.

ZS6KMD Nescafe 4:1 Balun - Making a 4:1 balun with a nescafe coffee jar lid and a toroid

The Bazooka vertical  ^pop - This is a deviation from the wonderful antenna the Double Bazooka.

Bazooka vs Dipole - Discussion, will a double bazooka outperform a dipole, enough to notice a difference on 40m.

The full-wave loop antenna - These omnidirectional antennas offer Horizontal polarization, and about 2.1 dbd of gain. They are much quieter than a dipole or a vertical, have a broader bandwidth and will usually out perform a dipole antenna.

Loop Antenna Design - Full-wave loops are very popular antennas. They are especially useful on 80 and 40 meters where they perform well at modest heights

High Performance Wire Antennas - Popularity doesn't guarantee high antenna performance, disadvantages of trap antennas

eham DX Spots - DX Spots web cluster interface with filtering features available to eham subscribers

Better RF company - Pre-recorded voice keyers, Tune controls for Yaesu FT-100, FT-857 and FT-897, Icom IC 706 and IC 718

BHI Ltd - Noise eliminating products. Remove unwanted background noise and interference leaving only the speech. Clear communications, listen stress free. Dsp noise cancellation solutions.

Electronika International Inc - Electronika International Inc, Cleveland, OHIO manufacturers wide range of Coaxial Cable Assembly, Coaxial Connectors & Adapters, Power Dividers, Attenuators, Coaxial Switches, Amplifiers, Fiber Optic cords, Bias TEE, Isolator & Circulator and other products

KK7UQ - Digital Radio - The KK7UQ computer to radio interface, sound card interfaces, IMD meters interface products

microHAM - Supply high quality accessories for your ham shack, including Band Decoders, various types of Antenna Switches, Antenna Stacking devices, special devices designed for the SO2R operator, USB Interfaces, Digital Mode Interfaces, Keyers and many others

Wilderness Radio - The only source for kits aimed specifically at the outdoor QRP enthusiast. These kits, field-tested by members of the NorCal QRP Club, represent the state of the art in portability, low power consumption, high performance, and flexibility.

Spectrum Instruments - Spectrum manufactures very high-performance, low-cost, GPS-disciplined time and frequency reference standards for industry, scientific, calibration, broadcast and amateur operators.

APRS using a weather station - Interface APRS to a weather station

SciTech Publishing - Publisher of many RF, Electronics and antenna books

Build An Audio Speech Processor - When one operates at low power on SSB, speech processing becomes almost essential to get through the QRM. The circuit is a low cost speech processor that will perform well with a minimum of construction effort.

Choosing Wire Size for Toroidal Inductors - Measurements that show it doesn't make much difference

Simple Electronic Keyer - A simple keyer which can be built for as little as $6 with some junk box parts. Although this circuit is not a true iambic keyer, it is capable of producing perfectly sounding CW.

RFI From Computer Networks - Is your router shutting you down ?

Television channel 11 interference. - Solving interference from television channel 11 on 144MHz transverters by Chris Cox, NĜUK, G4JEC

Automotive RFI elimination - ARRL pdf file on how remove car noise from your radio. Modern vehicles are RF noisy environments. Come learn how to identify and silence yor mobile noise sources, by WA6PDP

ARRLWeb: Solving Ignition Noise RFI - Solving Ignition Noise RFI article. Help on removing noise interfences caused by ignition

Alternators & Batteries - Influence of batteries on RFI and noise generation by k0bg