When I look at file 10 I see
Obs. program = AO123 Obs. ID =1231, Freq(Ghz) = 1.36490
Subarray = 1 Channel code = 13107 Correlator mode = 4
Timerange = 19960309 at 11 3 35.0 to 13 31 0.0
1695 VLA archive records, approximately 616980 vis.
Obs. program = AO123 Obs. ID =1231, Freq(Ghz) = -1.01490
Subarray = 1 Channel code = 13107 Correlator mode = 4
Timerange = 19960309 at 13 32 20.0 to 13 32 20.0
1 VLA archive records, approximately 364 vis.
Obs. program = AO123 Obs. ID =1231, Freq(Ghz) = -1.01490
Subarray = 1 Channel code = 13107 Correlator mode = 4
Timerange = 19960309 at 13 32 25.0 to 13 32 25.0
1 VLA archive records, approximately 364 vis.
Obs. program = AO123 Obs. ID =1231, Freq(Ghz) = -1.01490
Subarray = 1 Channel code = 13107 Correlator mode = 4
Timerange = 19960309 at 13 32 30.0 to 13 32 30.0
1 VLA archive records, approximately 364 vis.
Obs. program = AO123 Obs. ID =1231, Freq(Ghz) = -1.01490
Subarray = 1 Channel code = 13107 Correlator mode = 4
Timerange = 19960309 at 13 32 35.0 to 13 32 35.0
1 VLA archive records, approximately 364 vis.
Obs. program = AO123 Obs. ID =1231, Freq(Ghz) = -1.01490
Subarray = 1 Channel code = 13107 Correlator mode = 4
Timerange = 19960309 at 13 32 40.0 to 13 32 40.0
1 VLA archive records, approximately 364 vis.
In other words some good data that go to one of the good files and
then 4 individual times with odd frequencies. It is these 4 times
that create the 4 empty UV data sets.
You may simply ignore (zap) them. You are getting all the good data
there are.
Eric Greisen