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Articles about TM-D710 radio modifications at Mods.dk -
Smart antennas or the adaptive antenna array and smart antenna technology used with SDR, cognitive radio, MIMO, and other new technologies. -
Online Constant - k Lowpass Filter calculator -
ICNIRPcalc allows you to calculate safety distances for many know amateur radio antennas with respect to ICNIRP limits by DL9KCE -
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A portable decoder for METEOR M weather satellite LRPT signal, available for windows and Linux -
A summary, overview or tutorial covering the basics of Meteor Scatter or Meteor Burst Communications, a form of radio signal propagation often used at VHF. -
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Kings county repeater association review of the Baofeng UV-3r -
Near Vertical Incidence Skywave propagation is a form of radio wave propagation used on the MF and HF bands to provide radio communications and broadcasting coverage over short distances, especially where the terrain contains obstacles. -
The basics of radio receiver dynamic range performance used for specifying the performance of radio receivers used in radio communications systems. -
Article on Yagi and Log periodic antennas by Tom, K1JJ -
An overview of the development of the Morse key for sending the Morse Code, from the first camelback keys, through straight keys and sideswiper keys to the semi automatic keyers including the Vibroplex to the modern electronic keyer. -
Article on antenna feed impedance and the importance of matching RF andtennas to feeders, including notes on Radiation resistance, loss resistance, and efficiency are also detailed. -
Upload an ADIF fiel and plot all worked grids in an online map. Support filtering by band, year and can export the output directly into a google map, or a google earth KML file -
About antenna or aerial resonance and bandwidth and the impact of RF antenna resonance and bandwidth on radio communications systems. -
STØR Souther Sudan dx pedition july 2011 -
Articles and review on the Yaesu FT 817 by OZ9AEC -
UV5R / UV82 series UV5R, UV82, GT3, BFF8, F8HP, etc Keypad Layout and Functions -
A linear regulated power supply 2A, 20 V designed mainly to get used to soldering and have something usefull as final result. -
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The details of the spark gap transmitter and its history: how it was invented, developed and used. -
Article on propagation basics. The ground wave used for radio communications signal propagation on the long, and medium wave bands for local radio communications -
The _Touch CPO_ circuit offers a unique method for Morse Code practice, eliminating the need for a physical key. It leverages the versatile IC555 timer, configured as an astable multivibrator, to generate an audio tone. Users can adjust the tone's frequency by manipulating a 100 K variable resistor connected between pins 7 and 6 of the IC555, providing flexibility in the practice experience. Volume control is achieved via a 10 K variable resistor, while a 1 K Ohms preset at pin 4 of the IC555 allows for fine-tuning the touch plate's sensitivity. The design connects the touch plate to the base of a BC147B transistor, a configuration noted for its flexibility regarding the length of wire between the transistor and the touch plate. The author's prototype successfully used a 9 cm wire with a 3 x 6 cm aluminum plate. This project also suggests an alternative application as a touch-operated doorbell, demonstrating the circuit's adaptability. The design emphasizes simplicity and ease of construction, making it accessible for hams interested in DIY electronics. -
A short introduction to amateur radio portable operations bu VKFAQ. -
All the essentials about the Dip Meter or Grid Dip Oscillator used for many RF measurements including detecting resonance, locating RF emissions, and making many RF measurements. -
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Descriptions, summaries,and tutorials about electronic circuits and electronic circuit design including amplifiers, attenuators, logic, transistor, operational amplifiers and much more -
overview of radio signals and radiowave propagation and how different areas of the atmosphere affect radio communications. -
Bearing Info uses an extract from the VKLogger.com web site Op-Info to make it easy to find a callsign and hence bearing and distance information. It is written specifically for VK operators for use in Field Days although it could be considered a general purpose amateur radio utility, mainly for Aussies by VK4ADC -
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Article about the microstrip antenna, which is also commonly referred to as the patch antenna. -
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A yearly contest calendar with most interesting amateur radio contests and QSO parties collected by Carolina DX Association -
Article on how to use logic analyzers for testing complex logic-digital circuits -
The I2YSB DXpedition Team presents a collection of videos documenting their past DXpedition activities. These visual records offer insights into the operational aspects, equipment deployed, and environmental conditions encountered during various DXpedition events. The resource also contains a specific announcement regarding the cancellation of the planned Ghana AF-084 DXpedition, originally scheduled for April. It further details the refund process for sponsors who had contributed donations for the cancelled operation. The content serves as an archive of DXpedition experiences, showcasing the efforts involved in activating rare or challenging entities. It provides a historical perspective on the team's operations and logistical considerations. The site also functions as a communication channel for important updates concerning future or cancelled DXpedition plans, directly addressing the amateur radio community interested in their activities. -
Official page of the IARU High Speed Telegraphy Championships -
A description and build-log of a cheap telescoping mast made from PVC pipe, string, and some misc mounting hardware. It is useful if you are going somewhere that doesn't have any trees nearby to hang something on. -
Introduction to troposcatter or tropospheric scatter propagation using the troposphere -
A complete list of resources for the Kenwood TS-850 mantained by TK5EP -
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An introduction to develpment of morse keys in radiotelegraphy history -
AmTOR may be considered as the next development from RTTY. AmTOR was introduced to overcome the problems with RTTY. As a result of its performance, it has become popular on the HF bands because it gives more reliable communication, especially when interference is present. It achieves this by using a coding system that allows errors to be detected and corrected. -
New PA stage for good old Atlas 350XL HF transceiver -
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Introduction to packet radio and answers to common questions about this digital mode and about services you can use by VKFAQ
