History of FCC Band-Plan Allocation?

SSTJ

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I'm wondering if anyone can recommend some reading (preferably a book) on the history of FCC band allocations. I'm interested in understanding the reasons that certain bands have been allocated to certain purposes, whether it's CB, Ham, FM Broadcast, etc. I figure that the answers will be more historical than technical.

Thanks for any recommendations.
 
Several books are available about the history of radio. I learned simply by learning the physics of RF, part of the deal is who learned what and when. The band plan is easy when you look at it from that perspective. I'm sure any dedicated "history of radio" book will be fine. Personally I think you should pick up a college level physics book and go there. I think the second course is basic EM after mechanics. That's where you want to be.
 
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Several books are available about the history of radio. I learned simply by learning the physics of RF, part of the deal is who learned what and when. The band plan is easy when you look at it from that perspective. I'm sure any dedicated "history of radio" book will be fine. Personally I think you should pick up a college level physics book and go there. I think the second course is basic EM after mechanics. That's where you want to be.

Thanks. I've got the physics coming along well, so I'm looking for the more historical, "here's what they were thinking at the time", or "here's what was going on at the time" kind of answers.
 
One more thing that affects the US's band plan is international treaty. Much of our band plan is governed by those treaties so it's not something that was just dreamed up by the FCC. There is sound reasoning behind most of it.

Many, for example, have no clue why our CB radio AM transmitters are limited to 4 watts. That's because the band's 40 channels are packed tightly into a narrow space of the band and each channel only has a very small bandwidth that is available. The more power an AM transmitter puts out the wider its signal becomes. Which is why someone running a higher than legal transmitter in the CB band can splatter across multiple channels at once and is why we're limited to 4 watts.
 
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One more thing that affects the US's band plan is international treaty. Much of our band plan is governed by those treaties so it's not something that was just dreamed up by the FCC. There is sound reasoning behind most of it.

Many, for example, have no clue why our AM transmitters are limited to 4 watts in the CB band. That's because the band's 40 channels are packed tightly into a narrow space of the band and each channel only has a very small bandwidth that is available. The more power an AM transmitter puts out the wider its signal becomes. Which is why someone running a higher than legal transmitter in the CB band can splatter across multiple channels at once and is why we're limited to 4 watts.

Thanks Jerry. That's the kind of insight I'm looking for: historical, political, and technical.
 
One more thing that affects the US's band plan is international treaty. Much of our band plan is governed by those treaties so it's not something that was just dreamed up by the FCC. There is sound reasoning behind most of it.

Many, for example, have no clue why our CB radio AM transmitters are limited to 4 watts. That's because the band's 40 channels are packed tightly into a narrow space of the band and each channel only has a very small bandwidth that is available. The more power an AM transmitter puts out the wider its signal becomes. Which is why someone running a higher than legal transmitter in the CB band can splatter across multiple channels at once and is why we're limited to 4 watts.
That explains why the ratchet jawers on the 1KW xmitters always generate intermod RFI on adjacent channels. I didn't know this, thank you.
 
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There is some interesting history and politics between border states with mexico.

My understanding is that towers get put up south of the border, and get cranked to "11" cuz of their lack of regulation.

That is one reason radio stations in san diego use towers in tiajuana. (Spelling?)

And that is why you hear the mexican national anthem broadcasted at 12am over certain stations.... cuz they do that in mexico.



P.S: Just a heads up.... if you are at your friends party late one night in south san diego, and there is a sizable amount of mexican/hispanics in attendance....

when the clock strikes 12 am, and that american rock station your listening to plays the mexican national anthem due to mexican laws...

Do NOT goose step around the party during their time of patriotism. Appearently it is not appreciated by many.
 
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And that is why you hear the mexican national anthem broadcasted at 12am over certain stations.... cuz they do that in mexico.
I've woken up to our national anthem many times here in the US and had to drag my butt to bed. It used to be pretty common before they went 24/7 with everything.
 
Do NOT goose step around the party during their time of patriotism. Appearently it is not appreciated by many.
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:LOL:
 
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