Broadcast Radio Turns 100 109
GraWil writes "On Christmas eve 1906, a Canadian physicist named Reginald Fessenden presented the world's first wireless radio broadcast from his transmitter at Brant Rock, MA. The transmission included Christmas music and was heard by radio operators on board US Navy and United Fruit Company ships equipped with Fessenden's wireless receivers at various distances over the South and North Atlantic, and in the West Indies. Fessenden was a key rival of Marconi in the early 1900s who, using morse-code, succeeded in passing signals across the Atlantic in 1901. Fessenden's work was the first real departure from Marconi's damped-wave-coherer system for telegraphy and represent the first pioneering steps toward radio communications and radio broadcasting. He later became embroiled in a long-running legal dispute over the control of his radio-related patents, which were eventually acquired by RCA."
The Wireless (Score:5, Informative)
What I find interesting about the history of "radio" is that the word itself wasn't coined until some ten or twenty years after the invention. People used to call it "the wireless" before that. The guy who made up the word "radio" was an advertising expert named Waldo Warren. The same guy was later given the task to create a brand name for some of the early inventions of R. Buckminster Fuller. He came up with the word "Dymaxion", simply by jotting together syllables of random words Fuller used all the time: Dynamic Maximum Tension.
I like it that the word "radio" comes from the same heritage.
Ham radio to celebrate 100 years of broadcasting (Score:5, Informative)
How many broadcasters will let this event go unremarked? That is sad indeed.
Re:Super heterodyne? (Score:4, Informative)
Re:And just in time to see it fall! (Score:5, Informative)
The advantage of the microwave region is that a signal can occupy a larger range of frequencies and the wavelength from the low to the high end of the bandwidth doesn't change much due to the inverse relationship of frequency and wavelength. Calling it "satellite radio" is not deceptive except that it is a completely digital stream and the receiver's tuner doesn't necessarily tune to a different frequency for each "channel".
Re:And just in time to see it fall! (Score:4, Informative)
Microwaves are a subset of radio waves - there's nothing wrong with calling it "satellite radio".
The common usage of "Internet Radio" is the one that isn't technically correct, in most cases. (unless your 'Net connection is WiFi...)
Re:Super heterodyne? (Score:5, Informative)
"clear channel" stations are not allowed to increase power at night. While I haven't specifically mined the FCC database, I can say with considerable confidence that there are fewer than ten AM stations in North America that run more power at night than during the day.
However, "clear channel" stations are not required to *reduce* power at night. Most other stations are, and/or are required to switch to a directional antenna that concentrates all their power in a specific direction.
Technically, "clear channel" refers to the frequency, not to any specific station. For example, 720KHz is a "clear channel", and in theory any station operating on that frequency could call itself a "clear channel" station. Many do.
"clear channel" stations are divided into three classes, A, B, and D. Only one Class A station can exist on a frequency, and that's the dominant station most people think of when they think of a "clear channel" station. This station is allowed to operate 50,000 watts non-directional day & night, and is not required to protect any other station from interference. All other stations on the frequency must protect the Class A station.
For example, on 720KHz, WGN in Chicago is the Class A station. KDWN in Las Vegas is one of several Class B stations on 720; KDWN runs 50,000 watts 24/7, but is required to switch to a directional antenna at night, limiting the amount of power radiated in the direction of Chicago to maybe two or three dozen watts. (I think you can reasonably assume the KDWN transmitter is northeast of Las Vegas!).
Class D stations are those that are not allowed to operate at all at night, or are limited to nighttime powers less than that required for a new station. (generally, less than 250 watts; sometimes as little as one watt. No new Class D stations are being authorized.) An example of a Class D station on 720 is WGCR in western North Carolina, which goes off the air completely at sundown to protect WGN from interference.
Re:Radio Killed the Internet Star (Score:4, Informative)
Back then, radios were big, expensive things that really didn't handle multiple frequencies well. Changing the radio transmitter's frequency, even by a bit, could literally involve swapping out parts, changing the length of the antenna, and so forth.
Additionally, it would have been impossible for broadcast radio to become the medium it was without having fixed frequencies. How would listeners tune in? "Tune in tommorow, same time, at another random place in the radio spectrum!"
Finally, I find it incredibly improbable that radio hobbyists 80 years ago had access to computers suitable for frequency negotiation and hand-off.
No, regulation of the spectrum, at least to a degree, was and IS absolutely necessary.
Re:Tesla First, As Usual (Score:4, Informative)
Tesla also demonstrated, in a famous demo, how he could grab the electrode while holding a bulb in his other hand, lighting the bulb brightly. Edison was trying to set up Tesla's AC technique to power NY state's new "electric chair" executions, to scare the public away from letting AC be chosen to carry Niagara Falls hydroelectic (generated by Tesla's generators) down to NYC. But Tesla's demo showed everyone that "AC is safe", and the rest is history.
Re:Tesla First, As Usual (Score:3, Informative)