to keep the circuit closed after the timing signal expired.
As the generators would not operate
under no-load conditions for the length of time required (from H — 3 hours until after shottime),
a resistance with a rating of 7.6 ohms and capable of dissipating 1,600 watts was placed in parallel with the instrumentation. This load served to prevent spark plug fouling and other conditions
concomitant with no-load operation. The resistances were not disconnected when the instruments
went into operation, since the instruments required little amperage.
The output of the scintillation probe and photomultiplier of the dose-rate instrument was direct
current ranging from 0.05 to 500 ya for minimum to maximum incident gammafluxes. The di-
O° REFERENCE
LINE
STATION NUMBERS INDICATE
FROM
6.Z.
IN
AZIMUTH AND DISTANCES
HUNDREDS
OF
YARDS
0-160 4
0-t5.8
o-15.0
0-145
0-14.90
4
4
4
4
0-13.85 4
0-13.0 4
O-12.8 4
0-12.09
O-1tS 4
o-11.0 4
0-108 4
<q
0-98 4
0
i
200
300
{
400
{
o-as 7
O-78 4
0-65 4
0-88 4
O- 4.8 4
0-2.10 4
0-1.60 4
0-1.104
0-058 +
20
06-4125
139
(3.8
49
0-2504
3
é
146
162
o- 3804
0-310 +
:
es?
REFERENCE
LINE
Figure 2.3 Station plot plan.
rect current was impressed into the compressor-oscillator unit. In this unit, the direct current
was converted to pulses by a blocking oscillator. The pulses were amplified and recorded on
magnetic tape.
The probe consisted of an energy-compensated aluminum hemisphere with an interior plastic
scintillant. The entire surface of the hemisphere was coated with silver-activated zinc sulfide,
ZnS(Ag), and responded predominantly to gamma-ray energies below 130 kev. The light from
this coating and from the plastic scintillation crystal was converted by the photomultiplier to an
14