Dear All,
Thank you for your response, Really appreciate your time and help.
This issue has been resolved by activating the following shims on autoshim
panel.
z1, z2,X, XZ,Y, YZ
Previously those shims were not active (default ) by clicking the autoshim
button on the bsms-gui panel.
The solution to the problem is described here on this website.
https://chemnmrlab.uchicago.edu/2021/12/21/autoshim/
Regards
Vas
On Fri, Sep 9, 2022 at 6:28 PM Rajan K Paranji <rajanp_at_uw.edu> wrote:
> Hi Vas
> If lock drops on it's own, I will first look at the shim stack
> temperature stability. I don't have a Prodigy probe (yet; that will soon
> change :-\ ). If there is a thermal short of some kind, that can affect
> the shim stack.
> The RT shimming will always compensate for it and so there are no
> surprises there. If this is consistently happening, one way to approach
> this would be to carefully keep recording your shim files after every
> 'reshimming' you do. You can then try to track
> which RT shims are moving. Along with it, I will also track i.e. record
> the VT behavior. If my hypothesis of shim stack instability bears out then
> the VT record will show that the sample has been at a constant temperature
> while shims go bad. On the other hand, if your VT stability is the cause,
> the VT record will clearly show that. RT shim can always re-shim to
> accommodate sample temperature change and so there won't be any correlation
> between the two.
>
> I will be eager to know and learn what you find ! We are waiting for
> delivery of our Neo console with Prodigy probe by end of the year.
>
> Good luck and regards
>
> Rajan
>
> On Fri, Sep 9, 2022 at 12:38 PM AMMRL List <
> ammrlrev_at_webserver2.chem.hawaii.edu> wrote:
>
>> Dear All,
>>
>> We are not setting up any NMR experiments, After holding the sample (10%
>> D20 + 90% H20) and locking on (lock level : 75%-80 %) overnight. The
>> sample's lock is dropping to 50 % next morning.
>>
>> If we use the topshim command, The lock retains its original position.
>>
>> Could you please advise me on this matter ?.
>>
>> Sincerely,
>> Srinivasa R Penumutchu (Vas)
>> Chemistry Department, Millis, G27, Case Western Reserve University.
>> Email : srp106_at_case.edu
>>
>>
>>
>>
>
> --
>
> ____________________________________
>
> Rajan K Paranji, Ph.D.NMR Facility Manager
> *Department of Chemistry**Room 65, Bagley Hall*
> University of WashingtonSeattle, WA 98195
> phone : 206 685 2581 fax: 206 685 8665email: rajanp_at_uw.edu
> ____________________________________________________________________
>
>
>
>
>
Received on Sun Sep 11 2022 - 21:43:22 MST