[evlatests] correlator tests

[Brigette Hesman]

This past week we have been doing some correlator tests in C and X  
band on 3C286 using the full array and subarrays.  I created two  
observe files (one for C and X).  The basic format of the files are  
shown below:
C-band
1331+305     $00 03 00 13 31 08.2879 +30 30 32.958C    CC   A   2222  
7.47
//DS 1A          3
//LO      0.0    0.0      3860      3810              0000
//FISF          118.750000              218.750000
1331+305     $00 01 00 13 31 08.2879 +30 30 32.958C    CC   A   2222  
7.47
//DS 1B          3
//LO      0.0    0.0      3860      3810              0000
//FISF          118.750000              218.750000
... this type of card was repeated for all of the correlator modes.
X-band
1331+305     $00 03 00 13 31 08.2879 +30 30 32.958C    XX   A   2222  
5.23
//DS 1A          3
//LO     13.0   13.0      3540      3490              0000
//FISF          118.750000              218.750000
1331+305     $00 01 00 13 31 08.2879 +30 30 32.958C    XX   A   2222  
5.23
//DS 1B          3
//LO     13.0   13.0      3540      3490              0000
//FISF          118.750000              218.750000
... this type of card was also repeated for all of the correlator modes.

In our first attempt we ran both of these files using subarrays.  All  
of the VLA antennas were used to observe C-band and all of the EVLA  
antennas were used to observe X-band.  After looking at the data I  
found the following results:
1. In the 1A, 1B, 1C, 1D modes I found no unknown troubles with  
either X or C band
2. In 2AB, 2AC, ... modes I found the following issues:
	Subarray 1 - EVLA - X-band - 0 phases and high amplitudes were  
observed on antenna 24 with all baselines except 24-18.
	Subarray 2 - VLA - C-band - 0 phases and high amplitudes were  
observed on antenna 15 with all baselines except 15-4,5,6,8,20,22.
3. In 4 mode I found the following issues:
	Subarray 1 - EVLA - X-band - 0 phases and high amplitudes were  
observed on antenna 24 with all baselines except 24-18.
	Subarray 2 - VLA - C-band - 0 phases and high amplitudes were  
observed on antennas 6, 22, 15, and 28 with many baselines but not  
all (a list of the baselines showing this behavior is available upon  
request).
4. In the PA and PB modes I found the following issues:
	Subarray 1 - EVLA - X-band - 0 phases and high amplitudes were  
observed on antenna 24 with all baselines except 24-18.
	Subarray 2 - VLA - C-band - 0 phases and high amplitudes were  
observed on antenna 6 with many baselines but not all (a list of the  
baselines is available upon request).

Due to all of these issues we ran this test again using the full  
array.  When I looked at the data I found none of the above listed  
issues.  These issues appeared only when we attempted to use subarrays.

Brigette

************************************************

Dr. Brigette Hesman
EVLA
Array Operations Center
NRAO	
Socorro, NM 87801
bhesman at aoc.nrao.edu
Phone: (505) 835 7491

************************************************