The Gain of an Endfire Array
- This article looks at the maximum theoretically possible directive gain that could be obtained with an endfire array of given length or number of elements, and compares this with practical results in the literature.
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
Folding the Dipole
- Invented by Heinrich Hertz in around 1886, the half wave dipole is still one of the most simple and practical of antennas and still very much in use today. It consists of a half wavelength long centre fed conductor
- This Blog is about the Hong Kong Radio Amateur Station VR2UIX, rigs, antennas, accessories, DXing activities, HAM resources, knowledge, theory, practices, management, information technology and personal interests.
HxPI Radio - First Steps Radio
- First steps in science and technology. First steps radio. Color graphics and simple explanations of basic concepts in radio. An introduction to radio communication as a technical hobby. Resources for teaching, training, learning, self-study. Modern morse code. Morse code in the 21st Century. Morse code as a technical hobby. Morse training and practice material. Exercise files to download.
- Filtroid is an extremely easy-to-use program for synthesizing microwave filters. It can be used to design practically all filter types from audio to microwave frequencies as well as amplitude and delay equalizers and attenuators.
- RufzXP is an excellent free training software for improving code speed and CW practice, particularly (ultra) high speed memory copying of true amateur radio calls.
On Air CW Practice Program
- This program is designed to send code practice lessons over the air. You can schedule sessions in advance, and the program will automatically begin at a scheduled time and ID automatically. Freeware
HamMorse for iPhone
- Ham Morse allows you to practice morse code on your iPhone or iPod Touch. It is designed particularly for Ham radio operators and others who wish to achieve or maintain a high level of proficiency in this classic mode of communication.
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