rf spectrum

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.

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.

Coax velocity factor - Coax Cables velocity factor article in pdf format

Common Mode Choke Theory - A common mode choke may be used to reduce a type of electrical noise known as common mode noise. Electro-magnetic interference (E.M.I.) in the circuit's environment is one source of electrical noise.

300 Ohm Twin-Lead J-Pole - popular 2-meter emergency antenna that can be found all over the internet and in antenna books.

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.

SSB Electronic USA - manufactures and distributes HF, VHF, UHF and SHF equipment covering 10MHz. - 47.0GHz. Our products include: Wireless LAN / WAN Bidirectional Linear Amplifiers, Low Noise Preamplifiers - LNA's, RF Linear Amplifiers, Relays, Transverter Systems, Frequency Translation Systems, Downconverters, Antennas, Parabolic Dishes, Coaxial Cable, Relays, Antenna Switches, Microwave Test equipment, PC controlled Receivers, Microwave Linear Amplifiers including models for Telemetry, Wireless, and CDMA applications.

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

Saratoga ham radio products - Saratogaham.com brings you the latest product news and information about saratoga amateur radio products, Power meters, power panels and PSK radio to pc interfaces

Expanded Spectrum Systems - Flash crystals, Feakin' beacon keyer, beacon attenuator

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

Antenna Model - Commercial software for the analysis of wire antennas. runs under most Microsoft 32-bit Windows operating systems—Windows 98/ME/NT4/2000/XP Analyze most wire antennas in free space, over perfect ground, or over real-world grounds with the conductivity and dielectric constant you specify. You describe the antenna to the program in easy-to-use spreadsheet-style input window

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.

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.

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