THERMISTORS 
strip chart recorders that had fixed ranges. The output was attenu- 
ated so as to make a range of 100 feet cover the calibrated part of 
the recorder. Also, a bucking voltage was added to the positive 
output in order to use several overlapping ranges, each of 100 feet. 
DATA RECORDING SYSTEMS 
At the present time there are two independent data recording 
systems, one of which is the visual monitor and data recording sys- 
tem (fig. 7). This system is the more simple in form and was in- 
itially used as the only recording system. Temperatures from five 
thermally lagged thermistors were recorded on the first five chan- 
nels of a six-channel strip chart recorder while the sixth channel 
recorded depth readings from the pressure transducer. The re- 
corder used was a Minneapolis Honeywell, universal multipoint, 
potentiometer type, model 153 x 82, with a 0-2 millivolt range.* 
*Minneapolis-Honeywell Regulator Co. , Wayne and Windwin Avenues, 
Philadelphia 44, Pa. 
FU Wle 
COATED 
a lwie 
nese 
BRIDGE 
SIX 
CHANNEL 
M-H 
RECORDER 
ERESSURE 
TRANS-— 
DUCER 
DEPTH 
BRIDGE 
SINGLE 
ONE ONE 
UNCOATED TEMP SOIANINEIE 
THERMISTOR SRIDICE M-H 
RECORDER 
Figure 7. Visual monitor and recording system 
13 
