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Old July 14th 07, 05:28 PM posted to sci.electronics.basics,rec.radio.shortwave,rec.radio.amateur.antenna,alt.cellular.cingular,alt.internet.wireless
Ron Baker, Pluralitas![_2_] Ron Baker,    Pluralitas![_2_] is offline
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First recorded activity by RadioBanter: May 2007
Posts: 92
Default AM electromagnetic waves: 20 KHz modulation frequency on an astronomically-low carrier frequency


"Brenda Ann" wrote in message
...

"Ron Baker, Pluralitas!" wrote in message
...
|
| "Rich Grise" wrote in message
| news | On Wed, 11 Jul 2007 22:52:17 -0700, Jeff Liebermann wrote:
|
| "NotMe" hath wroth:
|
| (Please learn to trim quotations)
|
| Actually the human ear can detect a beat note down to a few cycles.
|
| If you are talking about the beat between two close
| audio frequencies then one can easily hear a beat way
| below 1 Hz.


But what you hear below ~20 Hz is not the beat note, but changes in sound


Semantics.
The "beat" heard in tuning a guitar is commonly
referred to as a "beat".
Yes, it is not the same thing as the "beat" from
a BFO in a radio receiver.

pressure (volume) as the mixing product goes in and out of phase. This
actually becomes easier to hear as you near zero beat.