air wound balun

Petlowany Antennas by K6NO - WorldRadio Article on Petlowany antennas base on this principle: if a length of wire is wound into a spiral-shaped coil and excited by a radio frequency current connected to the innermost portion of the coil, it will then, and only then, exhibit RF characteristics that closely approximate those of a resonant linear wire of the same length

Balun Construction - Construction and use of broadband transformers

QRP Balun - Pictures and assembling instructions of a simple qrp balun

WB6ZQZ Triple Ratio Balun - This balun matches resonant antennas from 9 to 75 ohms without a tuner and provides RF isolation to keep the current off the transceiver case

The Ugly Balun - A 1:1 choke balun for 160 thru 10 meters using one continuos lenght of coax to rig.

Simple HF Baluns for 50/75 ohm coax - Show diagrams, winding methods and tables of some 1:1 and 4:1 baluns for 1.8 - 30 MHz suitable for use up to 200W (400W peak) on systems using 50 or 75 ohm coaxial cable input where SWR should not exceed 1.6:1.

Practical Guanella 1:1 balun - This article proposes a lossy transmission line model of a practical Guanella 1:1 balun that is effective for all frequencies within and immediately adjacent to the pass band

4:1 balun for 160 to 10 meters  ^pop - Articke By Clay Wynn

Double Bazooka Dipole - The Double Bazooka Dipole is a very efficient antenna which is very quiet,and does not require the use of a balun

Soft copper Tube Loops - Air conditioning soft copper tubes are perfect for loop construction. If you want to try a loop you must have an air variable capacitor or a vacuum variable capacitor. Article by PY1AHD

QRP Antenna 80-40-20-15 End Fed Antenna - A long wire antenna that will load up on 80, 40, 20 & 15 meters without an antenna tuner and without balun coils

Radio Collectors : Radio World - A selection of radio collectors from all around the world interested in collecting, repairing, restoring, trading, selling parts, radio magazines, advertising collectibles, old records and technical talk.

Radio Repair Guy - This site is dedicated to the repair, restoration, preservation and sale of old collectable radios, both bakelite and wood.

K7FFF Beacon - FISTS Northwest K7FFF Beacon On the air at 28.287 MHz 2W to Dipole

N8YEL - Zeeland, Michigan

N4HLF KG4KIZ - Beacon On The Air Since 1999 and runs 24 / 7 and SHARED with KG4KIZ.

Greater Bridgeport Amateur Radio Club - Greater Bridgeport Amateur Radio Club helps to provide vital Emergency Communications through amateur radio to Southern Fairfield County and the Derby area.

W5GAD Jefferson Amateur Radio Club - Jefferson Amateur Radio Club JARC was originally founded in 1956. We're located just outside of New Orleans, Louisiana in the suburb of Metairie

CoaxMan - The Coaxman by Clear Signal Products, Inc. features a complete Wireman line of coaxial cable and antenna wire. Antenna wire, baluns, coax connectors, insulators, ladder line, magnet wire, rope.

Communications via aircraft reflections - Using aircraft as reflectors for amateur radio vhf communications by Lionel Sear, G3PPT

MiniErrorCorrection Program - This simple program was written as a possible utility for those attempting to communicate using digital modes via paths that are intermittent and tenuous such as Aircraft Scatter at VHF and Low Earth Orbiting Satellites by G3PPT.

LCLAYOUT drawing software - Simple inexpensive program that allows L-C filters designed by PCFILT or S/FILSYN which are to be built using air wound inductors and single layer capacitors cut from alumina or duroid substrate materials

144 Mhz power amplifier 4CX250B - This page provides information on the design and practical implementation of a rather inexpensive 144 MHz high power amplifier using a pair of ceramic tetrodes type 4CX250B by LA0BY

Tutorial on ferrite balun cores - Toroid cores, ferrite rods a good electrical tutorial on baluns

HP141 Clinic - Some observations on hp141 repair by Sam, WB8ZDF