amplifiers rf

Balun and Transformer Core Selection - Occasionally errors are made regarding core selection. This especially includes baluns, where on occasion some very strange ideas surface.

Transmitting Baluns - One of the most popular Ham-lore rumors is a balun's performance can be tested or evaluated by grabbing the coax and watching for an SWR change. This is probably one of the worse test-rumors circulating

RF in shack with vertical and longwire antennas - Why a vertical antenna or longwire antenna might require a balun

W1CG Low Power Balun Kit - Contruction manual to build a 4:1 balun, it has good performance from 160 through 10 meters.

Detuning Towers - The goal of detuning is not to avoid resonance, but rather to minimize re-radiation and/or current in the interfering structure.

A 16 Turn S-Band Helix - This design represents the smallest practical antenna for Oscar-13 mode-S. Perfect beacon reception at all times is possible, and acceptable SSB even at 43,000 km range.

13 cm Helix Antenna  ^pop - Here is the design of a 2.4 GHz antenna that is ideal for amateur satellite communications. This antenna is easy to assemble because the design itself tolerates inaccuracies in the construction without really affecting performance.

A Horn Antenna for 2.4 GHz. - This Antenna is not really practical for AO-40 reception, but horn antennas have a number of qualities useful in microwave antenna testing and noise figure measurements.

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

Radiation and fields - Electric Fields, magnetic fields, electromagnetic fields, losses, fresnel zone, nearfield and farfield

DirectionalBiQuad - Seattle Wireless - A biquad is a fairly powerful antenna which is relatively easy to construct, with impressive performance for their size. A link greater than 5 miles can be made with a pair of these as a stand-alone antenna and a Prism2 100mW card, provided you keep coax short, and your line-of-sight is clear.

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

Communication Concepts, Inc. - Provide components to the amateur who wants to construct their own gear and to the professional who wants to save money and time in prototyping their circuit design, Filters, HF Amplifiers, Splitter Combiners, VHF Amplifiers, ATV

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

F5VLB amateur radio astronomy station Priority listing - F5VLB and EA4EOZ have designed a small but powerful system using satfinder and standard LNB to make radioastronomy. A step by step descritpion for the novice about radioastronomy, VLB and listening to echo of meteorite.

ALA Amplifiers - Canadian dealer for many RF Amplifier brands

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