homebrew rf attenuator

Portable Magnetic Loop Antenna Version 2 - A simple multi-band magnetic loop antenna designed for 20, 30 and 40 metres. For its size, the performance of the antenna always astounds me, although it is never going to replace a Yagi

W5GI Mystery Antenna  ^pop - W5GI Mystery Antenna is a multi-band wire antenna that performs exceptionally well even though it confounds antenna modeling software. This antenna covers 80 to 6 meters with low feed point impedance and will work with most radios, with or without an antenna tuner. It is approximately 100 feet long, can handle the legal limit, and is easy and inexpensive to build. It�s similar to a G5RV but a much better performer especially on 20 meters.

W7AV 40 Meter Half Square - These antennas offer big gun DX performance on the low bands, yet they are surprisingly simple to build. Try one- you will like it!

YLRADIO - Full wave delta loop - This Delta Loop is a three-sided antenna suspended high in the air by vertical supports, such as tall evergreen trees. Recommended height is 40 feet or more at highest point, but higher is better.

Homebrew Balun Case - Balun case construction, tipically to host toroid cores. Size of case depends on power to handle. By DL5DBM

Balun construction  ^pop - PDF files describing how to homebrew a 1:2.5 balun

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.

LU9DPD Windom dipole - A multiband windom dipole antenna for 80 40 20 10 meters, feeded with a home made 4:1 balun, in spanish.

K0KP 10 Meter QRPp Beacon - Homebrew K0KP 500 Milliwatt Ten Meter Beacon. The beacon is located at the K0KP shack in Fredenberg, Minnesota, USA at Maidenhead grid square EN36VW

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.

SPE Amplifiers - SPE Makers of RF power amplifiers like Expert 1K-FA Expert 2K-FA

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

Eliminate QRM from 6 meters band - The circuit described below will substantially reduce or completely eliminate interference from almost any local source whilst leaving the wanted signal relatively unaffected, even though it may be on the same frequencey by TREVOR, G3ZYY

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

Lan Link for Windows - Lan Link for Windows by G3ZCZ, Internet interface to CXCluster, Controls PK-232, PK-900, PK-88, KAM, KPC-3, MFJ1278, and TNC2, PSK31 via the sound card in the PC, eQSL interface

HL1INF RF Amplifiers - Circuits, pictures and data about toroids, tubes and home made power amplifiers

GM3WOJ Amplifiers page - HF and VHF amplifiers homebrewed by GM3WOJ

Base-Station RF Power-Amplifier Biasing - Power amplifiers used in base stations require biasing for proper RF performance. This article explains the two classes of biasing that are prevalent in the RF industry, analyzes their characteristics, and shows implementations with existing ICs.

144/430 Duplexer - Schematics for a VHF UHF duplexer

A diode-switched band-pass filter - High speed silicn diodes work well as RF switches. This article describes how to use diodes for selecting two or more filters ARRL QST article by W1FB

DL5DBM`s 2 meter Antenna preamp - Homebrew with CF300 DGMF with about .24 dBD gain

RFI - Intermodulation - Getting squeaks and squawks from your H-T? Are pagers crunching your mobile rig's front end? Here's how intermod happens--and how to fight back!

The Basic Soldering Guide Photo Gallery - These photos illustrate the basic steps in making a perfect solder joint on a p.c.b