[evlatests] Some new phenomena

[Rick Perley]

    Calibrating two WIDAR databases, each with 4 IFs, has turned my fast 
machine into a digital snail, so while I wait for BPASS to grind along, 
here are some interim results:

    1) As reported earlier, we have no phase hops at all.

    2) But to replace them we have amplitude hops instead.  However, Ken 
has adequately explained them -- the amplitude changes (seen in both 
frequencies) always occur between scans, and are always the same amount 
-- corresponding to 1 dB change in power.  Hence, these are caused by 
the T304's attenuators.  We are not yet properly normalizing these 
cross-products (hence, they are not really correlator coefficients), so 
the change in power level is directly reflected in a change in apparent 
fringe amplitude. 

    3) Today's delays are the same as yesterdays, and are the same (to 
within 1 nsec) at both frequencies.  It would be awfully nice if 
somebody would put these values into the system, so I can avoid running 
FRING...

    For reference, here they are:

    1   29 nsec
    2   0
    3   71
    9   0
    18    12
    19    9
    23    3
    24    4
    25    18
    28    10

    4) Other than the amplitude hops, these data are of absolutely 
sterling quality.  (I had to QUACK the first 15 seconds of each scan, 
but that's due to the frequency change, and we have as yet no flags to 
remove these bad data automatically). 

    More, as my poky machine can provide them ...