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Excellent guide to build your own G5RV antenna by Lombry

Thierry LOMBRY, ON4SKY, develops in several long articles all you need to know about antennas, their design and performance, for both amateurs and SWL

Some tens of very special audio files recorded during amateur radio activities like aurora traffic, meteor scatter, communications with ISS crew and the sound of various transmission modes that you can hear on HF and VHF bands

Product review & short takes columns from QST magazine

Multi-band centre-fed antenna capable of very efficient operation on all HF bands, specifically designed with dimensions which allow it to be installed in gardens and other open spaces which accommodate a reasonably-straight run of 31.1m (102 ft) for the flat-top standard model.

Thierry LOMBRY, ON4SKY, develops in three long articles all you need to know about amplification, and how to seletc an HF and a solid-state amplifier, with pictures.

Interesting review about active magnetic loop antenna Wellbrook ALA 1530 and 330S by ON4SKY

Excel sheet containing technical comparisons of commercial HF portable antennas compiled by ON4SKY. Includes pictures, manufacturer, db gain, band coverage, F/B ratio, price, weight and dimensions.

A complete review of Icom IC-706 review published in 1999 by QST

Russian callsign prefix series: RAA-RZZ, UAA-UIZ, includs Amateur callsign system in Russia

NEC4WIN is a 32 bits commercial antenna simulation software based on MININEC3 developed by the Naval Ocean Systems Center in the 70s and 80s. It runs under Windows and can be used to simulate, analyze and optimize wire antennas, beams, verticals, etc. NEC4WIN has limitations. They are the same as Mininec3 on which the engine is based.

Thierry LOMBRY, ON4SKY, develops in several technical articles the way to select a transceiver. His website includes also some in-depth reviews

Thierry LOMBRY, ON4SKY, develops in several long articles the bascis of propagation. His website includes also a French section dealing with auroras.

The Yaesu FT-1000MP Mark-V, introduced at Dayton 2000 Hamvention, features a higher RF power of **200 W PEP** and a Class-A amplification SSB mode at 75 W. Key enhancements include an _Interlocked Digital/Analog Bandwidth Tracking system (IDBT)_, a Variable Front-End Filter (VRF) preselector, and improved ergonomics, notably a multi-function shuttle jog dial. This model, a successor to the 1996 FT-1000 and FT-1000MP, was designed to compete with high-end transceivers, despite its retail price of $4200 initially. The transceiver's physical dimensions are 406 x 135 x 348 mm (16 x 5.3 x 13.7 inches) with a weight of 14 kg (31 lbs), making it substantial. Its rear panel offers over 20 connections, including power, external DSP speaker, BAND DATA I/O, ALC, and multiple interface jacks for DVS-2, Packet, and RTTY. The unit also provides two keyer inputs, a DB9M serial interface for CAT, and two PL female antenna connectors, plus additional receive antenna jacks. Despite its advanced internal architecture, including two independent receivers with their own IF filters and AGC loops, the display technology, utilizing fluorescent discharge rather than LCD, contributes to an older aesthetic. The control panel is extensive, featuring 92 knobs and buttons, alongside numerous LED indicators for various modes and functions.

The Kenwood TS-570D(G) transceiver (I), by Thierry Lombry, ON4SKY

What become our QSL once sent ? QSL routes, IRC and green stamps, the best and worst practices.

Whith more than 20 years of ham practicen SWL Thierry LOMBRY, alias ONL5183, has written several technical pages about ham activities, including propagation, radio perturbations, radioastronomy, DXing, QSLing, ham-spirit, review of material and more. This very interesting website is completed by a large French section devoted to amateur astronomy illustrated with vivid colors pictures.

Modelling an horizontal Loop antenna at 3.5 MHz

In his back office section, ON4SKY, initiates in a few articles the beginners in the art of QSLing and award chasing.

Thierry Lombry, LX4SKY (aka ON4SKY) has developped a excellent educational website mainly devoted to amateur astronomy but it includes also a large section dealing with amateur radio activities includes several interesting pages about radio astronomy and SETI

Thierry LOMBRY, ON4SKY, gives advice to amateurs about lightning protection of an hamshack, including pictures and links.

Introduction to the use of clusters and Packet Radio, hardware, settings and commands by ON4SKY

Comparison of FT-1000D FT-736R FT-817 FT-847 FT-897 IC-765 Orion TS-2000 Spectral purity of a continous carrier, of a SSB and CW signals

Excellent article and guide to choose the best RF power amplifier that fit your needs by ON4SKY

The current, the voltage, the impedance, the bandwidth, the polarization, and how the earth influences the famous radiation pattern.

About DRM, the DRM standard, emission types, upfrading your old HF RX to DRM

Using NEC4WIN for Jpole antenna modeling

How to become an amateur radio ? by ON4SKY Review of general conditions to get licensed, examinations, regulation, CW, foreign calls, and more

Thierry LOMBRY, ON4SKY, develops in depth and with original pictures the long history of amateur radio all through the world from 900 BC to date.

Over 15 years of operational notes are documented on the AA6E Station Log, covering diverse amateur radio topics. The blog presents detailed accounts of station setup, antenna experiments, and digital mode operations, often featuring specific equipment like the _Ten-Tec Orion_ transceiver. It includes practical discussions on **station grounding techniques** and insights into PSK31 Morse code communication. The resource provides a chronological record of Martin Ewing's amateur radio activities, offering firsthand perspectives on equipment performance and operational challenges. Content often includes technical observations and solutions developed through practical experience, such as optimizing antenna systems for various bands. Specific entries detail contest participation and DX chasing, providing context for operational decisions and results.

The Orion II A9 Power Distribution Board Problem and Fix by N6IE

Ten-Tec Orion II picture and specifications at RigPix

eHam users review of the Ten-Tec Orion II model

Ten-Tec Orion picture and specifications at RigPix

eHam users review of the Ten-Tec Orion transceiver

Europeam perspective on BPL PLC

Simulation of a top loaded vertical antenna for 1.2 MHz

An excellent and comprehensive article on portable HF operations with attention on selecting proper equipment

The short history of the SSN Smoothed Sunspot Number at Luxorion

It is very compact, low noise and directive with an impressive 20 to 25 dB front to back

Effect of radials on the efficiency of antennas.

Developing operational amateur radio equipment for the 134 GHz band presents significant technical challenges, particularly in frequency generation and stability. This resource details the construction of a 134 GHz system, outlining its architecture with separate transmit (Tx) and receive (Rx) modules, each employing a local oscillator (LO) and RF head units. The system utilizes a dual Flann 50 GHz lens-type horn antenna configuration for optimal signal coupling. The transmit path incorporates an LMX2541 synthesizer chip operating at approximately 2.8 GHz, referenced by a 10 MHz double-oven Morion OCXO for exceptional stability. This signal is multiplied through a series of stages (X4, then X2) to generate a 22.4 GHz signal, which subsequently drives a dual series diode multiplier to produce the final X6 signal for 134 GHz operation. The receive side features an anti-parallel diode mixer coupled to a 144 MHz transceiver via a preamplifier, ensuring effective downconversion. Operational mode is CW, achieved by keying a multiplier stage. The project includes images of the Tx and Rx head units and describes a successful 3.5 km test with G8ACE, demonstrating stable signal tones due to PLLs locked to OCXOs at both ends, confirming the system's robust performance.

A multiple page article about assembling the antenna system, this section includes informations on constructing of the concrete tower base, starting from setting up correctly the foundations in relation to the antenna height.