from:	Zhao, Jun-Hui 
to:	"Thomas, Holly Sarah" 
cc:	chris sedgwick 
date:	Mon, Feb 5, 2018 at 3:06 PM
subject:	Re: MIRIAD WB5.0.7

The issue is due to the fact that current regular SMA operation are in dual receiver mode which,
in most cases, produce two frequency configurations while an SMA archival data set is  processed with
SMALOD converting the online data format to Miriad format. This is the step 1 in pre-process of SMA data for Miriad,
referred to as in  the lecture for handling SWARM data that I gave in our last Miriad users' meeting 
(https://www.cfa.harvard.edu/sma/miriad/userMeeting/2017DEC18agenda.html).

Only a few Miriad programs, for example UVINDEX and UVCAT, understand dual frequency configuration. Most programs
implemented for handling SMA data produced from 2GHz and 4GHz as well as hybrid ASIC and SWARM operations appear to
fail in handling SMA Miriad data packed in dual frequency configuration. To get around this problem, one need split the
dual frequency configuration into single frequency configuration with UVCAT before further process in Miriad usning the
regular routine programs such as UVAVER, SMAFIX, MFCAL, SMAMFCAL, SMAUVSPC etc. We have developed a
procedure in Miriad which makes SMA data, produced from SWARM correlator in daul RX operation, ready for further data
reduction (calibration and imaging) with globally distributed Miriad and/or other software packages. This step is referred
to as  the step 2 in pre-process of SMA data.

In the bottom section of the webpage for SMA SWARM data reduction guide (https://www.cfa.harvard.edu/sma/miriad/wbcorrTest/swarmbeta.html),
examples of C-shell scripts for step 1 and step 2 are posted. Here are the two scripts based on the test data used
in Glen P.'s bug report:
https://www.cfa.harvard.edu/sma/miriad/wbcorrTest/pscripts/swarmDRXload.csh.html      of step 1
https://www.cfa.harvard.edu/sma/miriad/wbcorrTest/pscripts/swarmDRX03pp.csh.html     of step 2 for the receiver pair 230 and 240


Jun-Hui