Hello Spinlanders
Thank you all for your offering of suggestions wrt lock and proton channel
problem posted last Friday and yesterday. The consensus of opinion was that
a room temperature or cryoshim had failed. This prompted me to try shimming
a sample in D3COD on the FID in unlocked mode.
Before doing so, I opened the console and removed the Aspect 3000 computer
in order to verify that the bank of cooling fans was functioning. I
discovered that the screen in front of the cooling fans had a fair amount of
dust that was impeding the flow of cooling air to the computer. I cleaned
the screen and blew down the Aspect's computer boards with a can of Super
Duster 134 Plus. Quite a bit of additional dust and debris was flushed from
the system. A couple of hours after the cleaning operation, as I began to
play with the shims, the proton channel returned to normal (before I had a
chance to change the shims). The lock signal for the sample in D3COD was
also back to normal.
The lock signal for a sample in CDCl3 is still very poor. I ran a 1 hour
and 40 minute 29Si experiment last night. The data was good. Proton data
last night and this morning is good. Any further suggestions as to how I
can diagnose and solve my hardware problem will be greatly appreciated.
Again, thanks to one and all. Best regards,
Lawrence
Lawrence Byrnes,
NMR Laboratory Manager,
Numare Spectralab Incorporated
10 Summit Avenue, # 6
Berkeley Heights, NJ, 07922
Research Director,
The Schoenenberg Instutute of Molecular Spectroscopy
75 Snyder Avenue, Berkeley Heights, NJ, 07922
Telephone 908-665-0066
Facsimile 908-464-4192
E-mail numare_at_eclipse.net
WWW
http://www.eclipse.net/~numare/
Received on Tue Jun 12 2001 - 12:15:26 MST