Radio waves

The short and long radio waves | Local news

In a burst of light in 1864, James Maxwell theorized that electromagnetic waves – radio and light – could travel through free space without the mythical “ether” or “quintessence.”

A few years later, Heinrich Rudolf Hertz – the unit of cycles per second bears his name – was able to prove that electromagnetic waves could propagate in free space, which confirmed Maxwell’s theory of electromagnetism.

In fact, for many years radio waves were referred to as airwaves. “Radio” is not an acronym or hyphenation, but is derived from the word “strike” or “strike”. Waldo Warren coined the word and it was adopted by the US Navy in 1912.

You see, the electromagnetic spectrum contains radio waves, microwaves, infrared light, visible light, ultraviolet light, x-rays, and gamma rays. These are all forms of electromagnetic radiation. Waves travel in interesting ways across our skies, in space, and even over land and oceans.

Today, the majority of the radio wave devices that most of us use on a daily basis operate in line of sight, which means that the radio waves travel in a straight line between the transmitter and the receiver, including the signals. for television, cell phones, walkie-talkies, wireless or Wi-Fi networks, telecommunications microwave links and even satellites. Other radio frequencies, like your AM – for amplitude modulation – the radio band can bend over obstacles like hills and travel well beyond the horizon. Your FM radio band – for frequency modulation – tends to be more direct due to its shorter wavelength.

Much lower frequencies can penetrate through water and land. Communications with submerged submarines and mine workers use very long wavelengths. The Navy’s E-6 Mercury aircraft tows a 5 mile long antenna in flight to communicate with our submarines, a very long wavelength indeed.

Shortwaves and other higher frequencies can travel across oceans and continents by ignoring or refracting an abundant layer of electrons and ionized atoms called the ionosphere that can extend 30 miles above Earth to ‘at the edge of space 600 miles away.

Some radio stations use shortwave to broadcast internationally. This method of diffusion depends on the upper atmosphere and is most reliable during long winter nights.

Wouldn’t you know, this is one of the frequency bands used by amateur radio operators. Since the early 1900s, no other group has made a greater contribution to radio communications than our valued amateur and so-called amateur radio operators. Even though they are licensed by the Federal Communications Commission, they are called amateur radio operators because the FCC has set aside certain non-commercial radio frequencies for their use.

Therefore, they are not allowed to accept any payment for their services.

But they’re just as innovative today as they were 100 years ago.

Amateur radio operators have a distinguished history of public service as well as emergency communications.

You see, when extreme weather conditions, floods, earthquakes, or forest fires occur, they can cause power outages or damage communications equipment, like cell phone towers.

When such conditions arise, amateur radio emergency teams spring into action and relay information on “health and wellness” and support first responders and government agencies with their radio equipment when other communication channels are available. inaccessible.

US broadcaster Art Bell, who died last week, became a licensed amateur radio operator at the age of 13. His call sign was W6OBB.

I often listened to his show on Sunday evenings on my way home from Naval Reserve exercise weekends at Naval Air Station Point Mugu.

John Lindsey is the marine meteorologist for Pacific Gas and Electric Co.’s Diablo Canyon Power Plant and a media relations representative.