Calibration procedure for fastT:  Steve Oncley  2/8/94
Done when a probe is put on or removed (if alive)

Requires two DVMs
1. Hook up DVM1 to signal through an extra 9-pin cable (some sort of 
   BNC/clip/banana adapter may be required) and a "T" adapter
   (the small aluminum box), so that the signal also goes through the
   data system.  (We should make up a cable specifically for this task.)
   Turn DVM1 to DC scale.
2. Hook up DVM2 to Fluke thermocouple adapter, turn adapter ON to degrees C.
   Turn DVM2 to 300mV DC scale.
3. Ensure that thermocouple is slightly visible inside temperature zero box.
4. Carefully put zero box over temperature probe
5. Plug thermocouple into thermocouple adapter.  There isn't a lot of cable,
   so be creative in trying to hold DVM2!
6. Adjust "null" pot until DVM1*10 = DVM2 (roughly)
7. Switch bridge switch to "gain".  Adjust "gain" pot until a change of 
   +0.500 V is observed on DVM1.  Since the temperature drifts with time, 
   this must be done quickly.  It probably will be necessary to switch back
   to center ("operate"?) and forth a few times.
8. Repeat above 2 steps until DVM1*10 is within 1 degree of DVM2 and gain 
   change is within 0.002 of 0.500 V.
9. Ensure that data is being archived
10. Switch to "null" for about 5 seconds, then back to "operate" for 5 seconds
11. Switch to "gain" for about 5 seconds, then back to "operate" for 5 seconds
12. Repeat above step 5 times total
13. Record time for later use. 
14. Carefully take zero box off of temperature probe.
15. Turn Fluke thermocouple adapter OFF
16. Turn DVMs off
17. Disconnect DVM1 connection to signal

Later:
18. Make "logbook" entry noting sensor calibrated and time

Even later analyze data:
19. Use the Splus routine, fun.fastT.cal.get, to output the calibration gain 
    value.  This requires that the archive file be online and has lots
    of parameters.  The output is a vector with the values of all large jumps 
    and the gain value using all these jumps.  It may be necessary to use a
    subset of this vector in the gain calculation.  See a DOWNWASH94 logbook 
    entry for examples.
20. Edit the previous logbook entry to enter the values from Splus
21. Edit the appropriate cal_files to enter new cal_file