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Mission is to preserve the history and enhance the knowledge of radio.

9Q0HQ Congo DXPedition Online Log

At LCWO you can learn Morse telegraphy (CW) online in your browser, use Koch Method, compare your results with others, speed practice and more

Web Morse Runne is an online CW (Morse code) contest simulator developed by DJ1TF - Thomas Fritzsche. This tool allows users to practice their Morse code receiving and sending skills in a simulated contest environment. Key configurable parameters include CW speed, with options ranging from 300Hz to 900Hz, and RX bandwidth, adjustable from 100Hz to 600Hz. Users can also set a monitor level and simulate various band conditions. The interface includes counters for calls and QSOs per hour, along with a timer. Pre-defined function keys are available for common contest exchanges such as F1 (CQ), F3 (TU), F6 (B4), F7 (?), and F8 (NIL). The simulator is designed for ham radio operators looking to improve their CW contesting proficiency.

Article about assembling of a Dick Smith Electronics (DSE) 100 Watt VHF Linear Amplifier kit.

Vanuatu - YJ 2010 - DXpedition info and online log

A new, simple way to build the Eggbeater Antenna. This document introduces a new, simpler way to build the Eggbeater antenna. It also introduces a technically proper way to construct the Eggbeater antenna in order to achieve the best result.

Log Online for HK0NA

A small Z-Match tuner, BLT, Balanced Line Tuner is a simple Z-Match tuner that works from 10-40 meters

TN5R Congo DX Pedition - Search the online log

Pitcarin 2012 - VP6T Online log at clublog

This article includes an online calculator for a 3 element Yagi Antenna. The formula and basics theory of Yagi Antenna are also explained with examples.

A post about the construction and measurements of a Resonant Feedline Dipole cut for the 10M band

Search K1N On-Line log

Types of coax-cable with rf attenuator calculator, line loss calculator form includes an antenna gain calculator. This coax loss calculator can help you on choosing the right cable for your antenna sysmte.

Log Online for T02TT DX Pedition

The 60-page PDF document, "Antenna Systems and Theory For The Non-Technical Ham" by Jim Abercrombie, N4JA, provides a foundational understanding of antenna systems. It explains basic antenna theory, including how antennas work, electromagnetic wave polarization, and the role of frequency. The resource details various antenna types such as flat top dipoles, inverted-V dipoles, shortened loaded dipoles, G5RV dipoles, Carolina Windoms, and end-fed configurations. Vertical antennas, including ground-mounted trapped verticals and inverted-L verticals, are also covered. Directional beam antennas like monoband Yagis, cubical quads, and log-periodic arrays are discussed. Propagation modes, including ground-wave, direct wave, and skywave propagation, are explained in detail, with specific attention to the D, E, and F layers of the ionosphere and their effects on HF communication. Technical concepts such as standing wave ratio, decibels, resistance, and reactance are defined, along with calculations for half-wave resonant dipole lengths. The document addresses feed-line radiation, balun applications, and critical antenna and tower safety considerations. It aims to dispel common antenna myths and educate hams on making informed antenna choices.

5M2TT Log Search Liberia 2011 dx pedition

3W6C on-line log DXpedition 2010

7O6T log oline - 7O6T Club Log

Hamradio page with pictures and links

An SSB radio for the HF bands will be presented. Featuring 12 to 20 Watts of output power (depending on DC supply), full DDS frequency generation, covering 6 major frequency bands (1.8, 3.5, 7, 14, 21 and 28 MHz) within the short wave amateur radio spectrum. The rig also features colored LCD and front panel backlight.

Ten essential tips and truisms for understanding HF antenna: Non-resonant wire dipole antennas fed with open-wire line and an antenna tuner can function effectively as multiband antennas, as detailed in "The Classic Multiband Dipole Antenna" by WB8IMY in March 2004 QST. Coaxial cable, unlike balanced parallel-wire feed lines, can cause RF to travel on the outer shield braid, leading to RF feedback to the station; a 1:1 balun at the dipole center can mitigate this by isolating the unbalanced coaxial feed line. Antenna gain is achieved by shaping and directing RF energy, with beam antennas concentrating power in a specific direction, and wire antennas also exhibiting shaped radiation patterns. An antenna tuner's primary role is to match the transceiver's 50-ohm output to the antenna system's impedance, allowing modern transceivers to deliver full power. Wire antennas do not always require center feeding; end-fed long wires or off-center-fed dipoles (like the Windom) can be used, though they often necessitate an antenna tuner and a counterpoise or radial network. Dipole antennas do not need to be perfectly horizontal; their legs can be bent or inclined, which affects feed point impedance and may require SWR experimentation with coaxial feed. Vertical antennas shorter than a half wavelength require an efficient ground system, typically comprising elevated or buried radial wires, with more radials generally leading to better efficiency. A 1:1 SWR indicates an impedance match but does not guarantee antenna efficiency; an inefficient vertical antenna with a poor ground system can show a low SWR while wasting most RF as heat. Investing in high-quality, low-loss feed line, especially coaxial cable, is crucial for maximizing RF signal transfer and overall antenna system performance.

On-line Log for XR0ZR DxPedition to JuanFernandez

Pictures of a monoband linear amplifier for 40m band - 2 x QB5/1750 made by 9A6A

This page is to provide links to resources and information regarding technologies to reduce computer interference

KB22UT Article on how protecting ham radio station and in particular I/O Lines such as AC power, coax cable, control circuits, telephone line.

Log Search for 9M0L Log online

The collinear antenna, or Marconi-Franklin antenna, is an omnidirectional, high-gain antenna composed of in-phase half-wave dipoles aligned vertically. By using quarter-wave transmission line segments, it maximizes gain at a low horizon angle, outperforming a half-wave dipole. Adding segments increases gain but narrows bandwidth. A popular DIY version, the CoCo antenna, uses half-wave coaxial cable segments connected by non-radiating transmission lines. Built with stable velocity factor cables, a matching quarter-wave sleeve balun, and ferrite rings for attenuation, the antenna achieves performance comparable to commercial models.

VK9MT Online Log Search - Mellish Reef 2014

Balanced feed with coaxial line by John F. Clemens W9ERN

Transmission Line 75 ohm to 50 ohm Transformers

Understanding Solid State Linear Amplifiers

FO8RZ Tahiti island OC046 by F5PHW from 2009 to 2011.

6BTV (or 5BTV or 4BTV) mod for 12 and 17 meter bands, how to make a 7BTV or 8BTV or 9BTV, easy and cheap

Manufacturing selling and supporting the classic W7FG True Ladder Line Wire and Antenna

Experiences with the end-fed dipole based on the concepts presented by J. Taylor in an article titled RFD-1 and RFD-2: Resonant Feed-Line Dipoles in QST. August 1991.

Win4K3Suite is an integrated control program for the entire Elecraft K-Line. It supports the K3, the KPA500, the KAT500 and the P3 Panadapter. Has a remote server mode as well, that supports P3 streaming video.

Whether Hamradio software, Transceiver or Receiver, WiFi sticks as well as practical accessories. Bonito have everything around the topic Hamradio.

Examine the function and operation of a common mode choke and the way it reduces unwanted interference. Common Mode Choke vs. Single Choke

Log Online ZK2C 2012

Taking the Raspberry Pi 2 for a Test Drive with GNU Radio. Installing GNU Radio and receiving aircraft radar with a USB TV tuner

The members of the Shoreline Amateur Radio Club reside in New Haven, Middlesex, and New London Counties.

Bristol Virginia, Washington County Virginia and surrounding area Police and Fire scanner

Log Online for FT4JA Juan de Nova DX Pedition

Demonstrates the principles of effective HF multi-band antenna systems, emphasizing the use of non-resonant antennas, understanding line attenuation, and the proper application of transmatches and baluns. The resource challenges prevalent amateur radio myths, such as the necessity of a 1:1 SWR at the antenna feedpoint and the misconception that reflected power is lost or damages equipment. It cites authorities like Jim Fisk (Ham Radio Magazine) and M. Walter Maxwell (W2U, QST's "Another Look At Reflections" series) to support its arguments, providing historical context and technical explanations for these long-held beliefs. The article details how to combine non-resonant antennas with appropriate feedlines and matching devices to achieve broad-band operation. It compares coaxial cable losses with those of balanced open-wire lines, illustrating how ladder line can significantly reduce attenuation and handle higher impedances, enabling an 80-meter dipole to operate effectively across multiple HF bands. Practical guidance is offered on transmatch operation, explaining impedance matching principles and debunking the idea that tuners merely "fool" the transmitter. It also clarifies the function and potential misapplication of baluns, particularly transformer-type baluns, in the presence of high SWR.

An article on RFD antennas, resonant feed-line antennas

T32 DX peditions logs, T32CI T32MI T32SI T32VI

Online Log and dx info for Southern Line Islands DXpedition 2010