At 21:27 29-03-1999 -0800, you wrote:
>On Mon, 29 Mar 1999, Bruce Lane wrote:
>
>> Actually, ASR-33's ran at 110 Baud rather than BPS.
>
>Same difference.
>
>(you were just joking though, I'm sure)
No I was not, and it's not necessarily the same (contrary to popular belief).
From 'Data Transmission, Second Edition' by Tugal and Tugal (McGraw-Hill,
1989), Pages 133-134:
"...The transmission rate is generally expressed in Baud (Bd). Although in
most systems it is equivalent to bits per second (b/s), the baud
transmission rate must not be confused with the information rate, bits per
second, the rate at which actual data are transmitted. One baud signal may
carry one or more bits of the data..."
The book goes on to detail some specific examples. In essence, in a case
where QAM (Quadrature Amplitude Modulation) is used between a pair of 9600
b/s modems, every discrete change in the signal represents four bits.
9600/4 = 2400, so the actual 'baud' rate of such a signal is 2400, even
though the bits/second is 9600.
They give another example specifically related to the transmission of
ASCII code where the baud rate is representative of the total number of
bits in a single character (11 in their example, made up of 8 data, 1
start, and two stop bits).
Anyway, it makes a good read. The book itself may be a bit dated, but the
principles don't change.
-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-
Bruce Lane, Owner and head honcho, Blue Feather Technologies
http://www.bluefeathertech.com
Amateur Radio:(WD6EOS) E-mail: kyrrin_at_bluefeathertech.com
SysOp: The Dragon's Cave (Fido 1:343/272, 253-639-9905)
"Our science can only describe an object, event, or living thing in our own
human terms. It cannot, in any way, define any of them..."
Received on Tue Mar 30 1999 - 00:48:35 BST