From: Thomas Loran (tom@loran3.net)
Date: Thu Jul 03 2008 - 13:10:31 ART
John,
The 8K difference is the 193 bit that is used for framing.
The physical speed of the a DS1 (T1 is an electrical specification)
is 1,544,000 including the bits used for framing (sf twelve frames
or esf 24 frames) so 192 bit a sec (one frame) * 8000 frames a
second = 1,536,000. With the framing bit he equation is 193 * 8000 -
1,544,00
8000 sample per second comes from nyquists theorem that state the
min sampling rate for analog to digital conversion is 2 * the
frequency. For historical reasons telcos sampled at a max voice rate
of 4khz
HTH
Tom
On Jul 3, 2008, at 9:54 AM, John wrote:
> The speed that I've always known is 1544 kbs. Now in almost all of
> the IE
> labs it's 1536 kbs. I've searched (probably in the wrong places)
> and all I
> get is 1544. Where in the heck are they coming up with 1536.... EU-
> T1?
>
>
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