ros mode

NVI 40 Meter Antenna Modeling - The idea of using a low mount dipole, enhanced with reflector wires directly beneath the dipole, on the ground, appears to be a very good approach to creating an NVI specific antenna for local HF operation.

A Cost Effective Current-mode 1:1 Balun - A cost effective current-mode 1:1 balun can be constructed from a length of coax and a rod typically used for a broadcast antenna loop-stick, some electrical tape, cable ties, a length of PVC water-pipe and some connectors.

The Guanella 1:4 balun - A cost effective current-mode 1:4 balun can be constructed from two lengths of coax, two ferrite rods, some electrical tape, cable ties, a length of PVC water-pipe and some connectors. This form of 1:4 current-mode balun is named after G. Guanella.

The Simple Collinear - Wherever there is a need for a vertically polarized omni-directional antenna with gain, a collinear is used. The vertically polarized collinear takes the form of two or more half waves in-line and in-phase, resulting in an omni-directional pattern with maximum radiation near the horizon.

Collinear Microstrip Patch Antenna - Design of a 869 Mhz Collinear antenna

Axial-Mode Helical Antennas - Notes on Axial-Mode Helical Antennas in Amateur Service. Helix Basics, Modeling Issues, and Short Helical Antennas Over Perfect Ground

The normal-mode helix antenna  ^updated - A helix will work in the normal mode when the diameter and pitch of the helix is less than 0.1 Lambda

A Portable Antenna for Satellites - A portable antenna for mode B and J satellites

Antenna Theory - Introduction to Electromagnetics, Maxwell's Equations, Transmission Line, Models, scale modeling, constants

Coax Traps from a Modeling Perspective - About Coax Traps, NC4FB examine the operation of coax traps through modeling.

Windom Antenna with 4:1 balun - The Windom is an Off-center wire multiband Antenna. The old version was fed just by a single-wire connected on 1/3 of antenna's overall length or with an open-line feeder (later versions). Here is another model with coaxial feeder, which is compatible with Solid States - 50 Ohm output transceivers .

Radios Antiguas Priority listing - Vintage radio collection from Argentina

Lincoln Amateur Radio Club - Everything you need to know about how to being a ham. Classes, testing, operating various modes and equipment

Queen City Emergency Net - We are a group of amateur radio operators, which exists to provide communications support to the American Red Cross -- Cincinnati Chapter, and have done so since 1941

C.O.S.W.N. Central Ohio Severe Weather Network - Providing real-time weather spotter reports for the following counties: Delaware, Fairfield, Fayette, Franklin, Hocking, Licking, Madison, Pickaway, Ross and Union.

KC8RLC Summit County American Red Cross Amateur Radio Club

Listen to Radio Meteors live - Echos of USAF (Formally NAVSPASUR) radar signals reflected off of meteor trails received at Roswell, New Mexico

HB9FX Internet Remote Base JN37XH Hochwacht Zofingen Switzerland - Tune and / or listen between 10kHz - 10GHz to professional Online-Receivers as Rhode & Schwarz EK070 or AEG E1900/3, Amateur-Radio-Transceivers, Web-SDR, Digital-Modes, Repeaters, EchoLink, APRS or control Antenna-Switch-Matrix, Antenna-Tuner, SWR & PWR- Control or Web-Cams.

Micro908 Kit - A re-usable control & computing platform for antenna measurement, PSK31 digital modems, audio filtering, signal source & VFO, memory keyer by AMQRP

Aeroflex - Aeroflex products support the Test and Measurement Instrumentation field; including aerospace, defense, wireless mobile and broadband communications. Aeroflex solutions encompass a full spectrum of instrumentation for solving test and measurement requirements.

BandPlans.com - Have you ever wondered where different modes should be operated, what frequencies to avoid as a courtesy like SSTV etc? This site offer a database for known net frequencies,known segments for different modes, known beacons

Choking on RF - The intrepid newcomer encounters common mode problems in a mobile environment. Implementing some common mode chokes will be possible to reduce interferences

Wadsworthsales - Manufacturer's representative of wireless communication radio equipment, 2-way radio sales, land mobile radio sales, repeaters, duplexers, antennas, pl tone, hf, vhf and uhf data modems and LAN ethernet radio modems for commercial and amateur radio users.

Yagi-logper - Yagi-logper is a linux GPL program to model a Yagi or Log-periodic antennas with horizontal cylindrical dipoles.

Lightning Safety & Power Quality Issues - LightningProtection: Lightning Safety & Power Quality Issues. A moderated professional forum by recognized experts, for accurate technical information on lightning, surge and grounding information.