Receiving Pulse-Code Modulation on AM radio?

Radium

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Sep 11, 2006, 11:35:09 PM9/11/06

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Hi:

Hypothetical situation: a PCM audio signal [24-bit and monoaural] is
transmitted through an analog 150 Khz AM carrier, an AM receiver on the
other end [tuned to 150 Khz] picks up the signal, and the reciever is
attached to a device that can recieve, process, and decode the PCM
audio back to analog and then send it to a loudspeaker. However -- in
this theoretical situation -- the environment is filled with magnetic
interference that affects all AM stations.

My question: Will the received PCM audio signal remain noticeably
"clean" to the listener or will he/she notice the magnetic disruptions
affecting the audio?

I ask because I think -- but definitely don't know -- that because the
received signal is digital, it is less likely that the static would
cause noticeable auditory disruptions when compared to analog. Do I
guess correct?

Thanks,

Radium

John Larkin

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Sep 12, 2006, 12:23:59 AM9/12/06

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On 11 Sep 2006 20:35:09 -0700, "Radium" <gluc...@excite.com> wrote:

>Hi:
>
>Hypothetical situation: a PCM audio signal [24-bit and monoaural] is
>transmitted through an analog 150 Khz AM carrier, an AM receiver on the
>other end [tuned to 150 Khz] picks up the signal, and the reciever is
>attached to a device that can recieve, process, and decode the PCM
>audio back to analog and then send it to a loudspeaker. However -- in
>this theoretical situation -- the environment is filled with magnetic
>interference that affects all AM stations.
>

Won't work. The data bit rate (for 44 KHz sampling) is 1.05 MHz, too
much to put on a 150 KHz AM carrier, at least without insanely exotic
modulation tricks.

John

Radium

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Sep 12, 2006, 12:26:54 AM9/12/06

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Just what are these "insanely exotic modulation tricks"?

Radium

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Sep 12, 2006, 12:28:39 AM9/12/06

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What is we use a 3 MHz AM carrier, instead?

Tim Williams

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Sep 12, 2006, 12:48:00 AM9/12/06

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"Radium" <gluc...@excite.com> wrote in message
news:1158032108....@d34g2000cwd.googlegroups.com...

> My question: Will the received PCM audio signal remain noticeably
> "clean" to the listener or will he/she notice the magnetic disruptions
> affecting the audio?

Think data error.

Tim

--
Deep Fryer: a very philosophical monk.
Website: http://webpages.charter.net/dawill/tmoranwms

Radium

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Sep 12, 2006, 1:03:45 AM9/12/06

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Tim Williams wrote:
> "Radium" <gluc...@excite.com> wrote in message
> news:1158032108....@d34g2000cwd.googlegroups.com...
> > My question: Will the received PCM audio signal remain noticeably
> > "clean" to the listener or will he/she notice the magnetic disruptions
> > affecting the audio?

> Think data error.

Could heterodynes [often heard as frightening high-pitched tones on
analog AM radio] cause data errors [or any other disruptions] in a
digital device receiving PCM signals on an AM station?

Eeyore

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Sep 12, 2006, 3:40:31 AM9/12/06

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Radium wrote:

They're more insane even than you !

Graham

John Larkin

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Sep 12, 2006, 3:17:55 PM9/12/06

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You'd have to research communications theory. Google "information
theory" and "Shannon capacity" to start.

John