Amateur radio direction finding (ARDF, also known as radio orienteering and radiosport) is an amateur racing sport that combines radio direction finding with the map and compass skills of orienteering. It is a timed race … Read More
What is a harmonic? A harmonic of a particular frequency (the fundamental frequency F) is a frequency that is an integer multiple of the first one. For example: if f = 125 MHz, the harmonics would … Read More
The 70-centimeter band is a popular UHF band. Equipment Single-band equipment for 70cm is rare, but many dual-band transceivers are available that operate on both 2 meters and 70cm. Available gear includes base stations, mobile units and HTs. … Read More
What is TVI? Simply, TVI is the interference of TV reception by transmissions from another source. In ham radio, we are specifically talking about transmissions from an amateur station, although it is not uncommon for … Read More
Log Periodic Dipole Array – (LPDA) What is it? The log-periodic Dipole Array (LDPA) is a multi-frequency antenna composed of a series of driven elements parallel to each other. One of the advantages of the LDPA is that … Read More
The term mode has varying meanings, according to the context, but the most common are permitted modes in amateur licensing. Waves have three characteristics that can be changed, Amplitude, Frequency and Phase. A mode is … Read More
Fundamentals An oscillator is an electronic circuit designed to produce either audio or radio frequency signals. These will generally have sinusoidal waveform, but other wave shapes such as square and sawtooth are possible. In radio … Read More
IRLP – What is it? IRLP (Internet Radio Linking Project) was created in 1997 by Dave Cameron VE7LTD with the aim of providing links, via the internet, between amateur radio installations. The key philosophy behind the project was … Read More
A filter is an electric circuit (often called a network) that allows certain frequencies to pass but rejects (attenuates) other unwanted frequencies.In general, filters are one of four types – Lowpass, Highpass and Bandpass (Notch) … Read More
