Dear spinlanders,
Recently our Bruker 400 instrument failed to give a proper spectra -
basically no signal on proton, carbon, etc. Wobb gave weird wavy pattern on
the screen even though the preamp was showing perfect green lights. I ran
some board tests, and the tcu board gave one error, SPPA 1 read=0 exp=8000.
Basically, wobb complains 'unable to get optimum RG value' and goes on to
show the wavy pattern.
I can still see spectra if the sample is very concentrated. Clearly
something is wrong. I am in touch with Bruker and we have replaced CCU and
TCU boards and the problem still remains. Voltages to AQS and some of the
freq outputs in and out of TCU were measured and they seem to be fine.
I appreciate any ideas to solve this.
Thanks.
Dr. Gopal Subramaniam (718-997-4123)
Department of Chemistry & Biochemistry
Queens College - CUNY
Flushing, NY 11367
Received on Thu Mar 31 2011 - 10:16:37 MST