Filters

What Is A Filter?

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

What Is A Vertical Antenna?

Vertical antennas, often simply known to amateurs as “verticals,” are antennas in which the driven element is vertical. Most common verticals are simply a piece of wire or aluminum tubing mounted vertically, but others, such as those designed for mobile … Read More

Mobile antenna

What Is A Mobile Antenna?

Mobile antennas are designed to be used for operation while in motion. Their uses include pedestrian mobile operation while walking, bicycle-mounted antennas for use while riding, and the most common form, automobile-mounted antennas for use … Read More

Resistors: Everything You Need to Know

Resistance and Resistivity Resistance (R) is the measure of how much an object – a resistor – opposes the flow of electric current. The resistance of an object is measured in Ohms (<math>\Omega</math>) Resistivity (<math>\Rho</math>) is a measure of … Read More

Decibels

Decibels: Everything You Need to Know

What is a decibel dB? Some facts a decibel is the ratio of two power measurements decibels have no units decibels is a logarithmic relationship a decibel is 1/10 of a Bel decibels were created … Read More

Capacitor

What Is Capacitor?

What Is Capacitors? A capacitor, also known as a condenser, is a device that stores energy in an electrical field. Capacitors are open circuits to DC current, but their impedance drops as AC current passing through … Read More

Feedlines

Feedlines: Everything You Need to Know

Otherwise known as transmission lines, feedlines are used to transfer RF energy between a Transmitter, Receiver or transceiver and the antenna. Types Three types of feed lines are used by amateurs: Coax, Balanced Line, and Waveguide. … Read More

Sunspot Cycle

What Is The Sunspot Cycle?

What is it? The sunspot cycle is generally known to be a cycle of approximately 11 years between successive peaks in sunspot activity. What is less known and understood is that with each successive 11-year … Read More