True, the older 16 bit digitizers did not support SIM mode.
> --- this is related to the fact that
> the A3000 uses a 24-bit word in memory, and you need two 16 bit spots in
> memory simultaneously to run SIM mode (if my non-digital memory serves
> me right, and my math that 2*16 > 24 :) ).
FALSE!! The word size has nothing to do with it. Each point, whether
digitized to 6, 12, 16 bits is averaged into a seperate 24 bit word.
That is one word for the "real" and one word for the "imaginary" part.
This is true regardless of whether the data are acquired in SIM or SEQ (QN)
mode. The reason why it is not possible to acquire in SIM mode is that the
older 16 bit digitizers had only one ADC and one sample and hold circuit.
Therefore only one point could be digitized at a time. The 12 bit
digitizers and the newer 16 bit digitizers have two sample and hold
circuits allowing them to acquire two points (one real and one
imaginary) at the same time.
> --- does anyone know if this has been
> cured in the more recent generations of machines/computers from
> Bruker?
Yes, newer systems can do _either_ SIM or SEQ mode acquisition
on both the 12 bit and the 16 bit digitizers (including the
wideline BC132). Both modes work; so you can decide which is better
for your application.
--
==================================================================
... ... Charles G. Thibault
. * . . Manager of Software Development
. . . . Bruker Instruments Inc.
B R U K E R Billerica, MA. 01821 USA
. . . . (508)667-9580 x218
. * . . cth@bii.bruker.com Internet
... ... ...!uunet!bii!cth UUCP
=================================================================