[daip] FRING fails after calibration with ACSCL

[Amy Mioduszewski]

Hi Walter,

Eric is away unfortunately and I don't really feel comfortable digging 
into FITLD.  Eric is back Oct 16.

Amy

On 10/07/2018 04:30 AM, Walter Brisken wrote:
>
> Hi DAIP,
>
> I'm working on VLBA dataset BB397A on parallax, user=397 indisk=1 
> catnum=1 .  FRING reports SNR=0 after application of calibration from 
> task ACSCL even though the delays are reported correctly in the 
> verbose messaging. Prior to application of ACSCL calibration (which 
> generated SN3 and merged into CL5), FRING SNRs were very high (100s).
>
> My suspicion is that recent changes to FITLD to change the visibility 
> weights are triggering the problem.  This claim is supported by a test 
> I ran where I used version='NEW' for FITLD, then switched back to 
> version='TST' for the remainder of the calibration.  In this case, SNR 
> values are back to expected levels.  This was done as user=397
>
> The details of the data reduction are found in AIPS script: 
> /home/parallax/VLBA/BB388/scripts/BB397A.cal
>
> If you want to run the data reduction script, note that BB388LINKS 
> points to /home/parallax/VLBA/BB388/links
>
>     -Walter
>