File header and naming notes:

We try to keep the standard CTD sensor configurations the same each cruise. But
there are times when we add a sensor such as the RINKO III oxygen optode. 
This can cause the cruise-to-cruise 'usual' sensor configuration to change. 
So sensor voltage headers have been relabeled to insure their identification.

The voltage headers in each .asc file have been relabeled from V# to ?????V, 
where ??? is the sensor descriptor. This allows data users to identify the 
voltage channel associated with each sensor.

These files are in the asc-hdr-btl subdirectory and labeled: 

YY-YYMMSC_LLLLSSSS_###D.asc or U.asc & .hdr

YY is century 
YYMM is year-month, usually the CalCOFI cruise designation ie CalCOFI 1511OC
SC is two-letter shipcode: SR = Sally Ride, NH = New Horizon, OC = Oceanus,
  OS = Ocean Starr, MF = Miller Freeman, M2 = MacArthur II, RR = Revelle,
  JD = David Starr Jordan, RL = Reuben Lasker, SH = Bell M Shimada.
LLLL is CalCOFI Line (eg 0767 = 76.7, 0833 = 83.3)
SSSS is CalCOFI Station (eg 1000 = 100.0, 0800 = 80.0)
### is cast or processing number (001 = Cast 1)
D or U is downcast or upcast

The original Seabird .asc, .hdr, & .btl files are available under the 
'original_asc-hdr-btl' subdir is the header or filename changes causes any
data user import issues. The sensor configuration (voltage channels) are recorded
in the .hdr file for each cast.

JRW 03/08/2017
