Hello Everyone;
I’d like to add an addendum—a reply to the summary I posted last week concerning the intermittent appearance
of bizarre, small “multiplets” (a kind of sawtooth pattern) adjacent to authentic peaks.
Thanks,
Karl Koshlap
Dear Karl,
as mentioned in my reply to you, could you please send me a screenshot of the "Lock Scan" with a D2O or DMSO sample? My guess is indeed a lock instability - the lock transceiver board may need to be exchanged. A tell-tale would be a spike at the beginning of the lock scan FID. My guess is that the influence of the sample position is only a "red herring" - this may only be the final trigger that drives it over the edge, but the underlying problem is a different one.
A frequency instability isn't out of the question either though, so if you happen to have access to a scope a good start would be to measure the 10 MHz signal of the RefGen board - if this is instable or has the wrong frequency (9.9 MHz or 11 instead of 10.0000) then this could be a defective RefGen board.
Best regards
Bert
Received on Mon May 10 2021 - 09:34:53 MST