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Old July 1st 07, 06:01 AM posted to sci.electronics.basics,rec.radio.shortwave,rec.radio.amateur.antenna,alt.cellular.cingular,alt.internet.wireless
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Default AM electromagnetic waves: 20 KHz modulation frequency on an astronomically-low carrier frequency

On Jun 30, 12:55 pm, John Smith I wrote:

Use simple logic, you can modulate a dc (0 Hz) with higher freq (voice),
(hint, your telephone line is an example) right?


The telephone does not use either AM or FM. It is simply the
electrical equivalent of the sound that gets into the microphone. You
input a 1 KHz tone into the microphone, telephone lines will carry a 1
KHz AC current to the destination. The louder the sound into the
microphone, the stronger the amperage in the telephone lines.

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Old July 1st 07, 07:49 AM posted to sci.electronics.basics,rec.radio.shortwave,rec.radio.amateur.antenna,alt.cellular.cingular,alt.internet.wireless
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Default AM electromagnetic waves: 20 KHz modulation frequency on an astronomically-lowcarrier frequency

Radium wrote:
You
input a 1 KHz tone into the microphone, telephone lines will carry a 1
KHz AC current to the destination. The louder the sound into the
microphone, the stronger the amperage in the telephone lines.


On a side note, its actually voltage modulation towards the subscribe and
current modulation back to the central office. The earpiece is a high
impedance (2,000 ohm) device that responds to voltage variations. The
carbon microphone element 220 to 200 ohms modulates the talk battery current.

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Old July 1st 07, 08:25 AM posted to sci.electronics.basics,rec.radio.shortwave,rec.radio.amateur.antenna,alt.cellular.cingular,alt.internet.wireless
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Default AM electromagnetic waves: 20 KHz modulation frequency on an astronomically-lowcarrier frequency

Radium wrote:
....

You miss the simple point, the dc is the carrier ... instead of dc, you
could put a 1 hz signal on the line and modulate it with your voice,
indeed, you can put a 30 hz signal on the line and modulate it with your
voice--if you can tollerate a bad 30 hz hum! But, who knows, perhaps
you are tone deaf to the 30 hz hum and would like it ...

JS
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Old July 1st 07, 04:14 PM posted to sci.electronics.basics,rec.radio.shortwave,rec.radio.amateur.antenna,alt.cellular.cingular,alt.internet.wireless
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Default AM electromagnetic waves: 20 KHz modulation frequency on anastronomically-low carrier frequency

On 6/30/07 11:25 PM, in article , "John Smith
I" wrote:

Radium wrote:
...

You miss the simple point, the dc is the carrier ... instead of dc, you
could put a 1 hz signal on the line and modulate it with your voice,
indeed, you can put a 30 hz signal on the line and modulate it with your
voice--if you can tollerate a bad 30 hz hum! But, who knows, perhaps
you are tone deaf to the 30 hz hum and would like it ...

JS


But you miss the basic point......

The topic was Amplitude Modulation.



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Old July 1st 07, 08:19 PM posted to sci.electronics.basics,rec.radio.shortwave,rec.radio.amateur.antenna,alt.cellular.cingular,alt.internet.wireless
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Default AM electromagnetic waves: 20 KHz modulation frequency on an astronomically-lowcarrier frequency

Don Bowey wrote:
[pure crap!]


"In the mid-1870s, a form of amplitude modulation—initially called
"undulatory currents"—was the first method to successfully produce
quality audio over telephone lines. Beginning with Reginald Fessenden's
audio demonstrations in the early 1900s, it was also the original method
used for audio radio transmissions, and remains in use by some forms of
radio communication—"AM" is often used to refer to the mediumwave
broadcast band (see AM radio)."

Taken from this URL: http://en.wikipedia.org/wiki/Amplitude_modulation

And, please read the WHOLE PAGE before making a larger idiot of yourself ...

JS
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Old July 1st 07, 08:46 PM posted to sci.electronics.basics,rec.radio.shortwave,rec.radio.amateur.antenna,alt.cellular.cingular,alt.internet.wireless
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Default AM electromagnetic waves: 20 KHz modulation frequency on anastronomically-low carrier frequency

On 7/1/07 11:19 AM, in article , "John Smith I"
wrote:

Don Bowey wrote:
[pure crap!]


"In the mid-1870s, a form of amplitude modulation‹initially called
"undulatory currents"‹was the first method to successfully produce
quality audio over telephone lines. Beginning with Reginald Fessenden's
audio demonstrations in the early 1900s, it was also the original method
used for audio radio transmissions, and remains in use by some forms of
radio communication‹"AM" is often used to refer to the mediumwave
broadcast band (see AM radio)."

Taken from this URL: http://en.wikipedia.org/wiki/Amplitude_modulation

And, please read the WHOLE PAGE before making a larger idiot of yourself ...

JS


I didn't read the link, as it has nothing to do with this string.

You posted to Radium's question about Amplitude Modulation, saying that on a
telephone line, the DC voltage is the Carrier and the microphone current (or
voltage if you prefer) is the modulation. Now THAT is un-pure crap and it
is what I responded to and which you deleted in this post hoping to look
better, which you don't.

I already conceded to your ignorance, so you really didn't need to post
more, but thanks for the opportunity to help.



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Old July 1st 07, 08:53 PM posted to sci.electronics.basics,rec.radio.shortwave,rec.radio.amateur.antenna,alt.cellular.cingular,alt.internet.wireless
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Default AM electromagnetic waves: 20 KHz modulation frequency on an astronomically-lowcarrier frequency

Don Bowey wrote:

[more crap!]


Oh, that explains it, your understanding of amplitude modulation is:

AM = Black Magic.

ROFLOL!

JS

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Old July 1st 07, 11:04 PM posted to sci.electronics.basics,rec.radio.shortwave,rec.radio.amateur.antenna,alt.cellular.cingular,alt.internet.wireless
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Default AM electromagnetic waves: 20 KHz modulation frequency on anastronomically-low carrier frequency

On 7/1/07 11:53 AM, in article , "John Smith I"
wrote:

Don Bowey wrote:

[more crap!]


Oh, that explains it, your understanding of amplitude modulation is:

AM = Black Magic.

ROFLOL!

JS


OK you stupid ****, I'm almost out of patience with your ignorance. I was
hoping you might learn something, but I see that is unlikely.

AM is a process of frequency multiplication. Now you tell me where you
think such multiplication takes place on a phone line, and I'll follow-uo by
telling why you're full of crap.

SIMECS!

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