Sabieh,
The phenomen you observe is well know and called digital noise.
Above a RG of about 512 or 1024 the S/N should not depend any more on the
receiver gain.
Regards,
Jochem Struppe PhD
Senior Applications Scientist
Bruker BioSpin Corp.
15 Fortune Dr., Billerica, MA 01821
Telephone (978) 667 9580 ext. 5113
Fax (978) 667 2955
Applications Support: applab@bruker-biospin.com
(978)667-9580 ext. 5444
|-----Original Message-----
|From: Muhammad Sabieh Anwar (by way of BUM <bruker-users-
|mail@purcell.cchem.berkeley.edu>) [mailto:sabieh@waugh.cchem.berkeley.edu]
|Sent: Wednesday, August 09, 2006 2:09 PM
|To: BUM
|Subject: Signal to noise ratio and receiver gain
|
|
|Hi I recently joined the list. My name is Sabieh Anwar and I am a post-doc
|in University of California, Berkeley. I am using two spectrometers, a
|Bruker Avance DRX 300 MHz and a Bruker Avance 700 MHz.
|
|I am observing a strange phenomenon: I was under the impression that
|changing the receiver gaiin (rg) should have no bearing on the signal to
|noise ratio (sino). However, on my 300 machien I can see the sino changing
|with rg, lower gain implying lower sino. Can there be a good reason behind
|this? Help will be appreciated, as always,
|
|Regards
|
|Sabieh
|
|
|--
|
|__________________________________________________________________________
|
|To subscribe/unsubscribe: Please send a note to
|
| bruker-users-request (at) purcell(dot)cchem(dot)berkeley(dot)edu
|
|For subscriptions, please include a list of Bruker instruments you are
|using, see http://www.cchem.berkeley.edu/nmr/BUM.txt
|E-mail archives are at http://calmarc3.cchem.berkeley.edu/archives/bum.html
|__________________________________________________________________________
This archive was generated by hypermail 2b29 : Wed Dec 27 2006 - 01:02:08 PST