ns»etintineatlrtineReie

an n we Sm AeAa a Aa A ce

Therefore, it was possible to plot the incident light, or ganna radiation,
as @ function of the dynode voltage.
All electronics were mounted inside a light-aluminum housing for protection from weather, thermal influences, end small blast pressures. The
output was recorded on a bristol recording millivoltueter, which rucorded

paca rates from 0.2 r/hr to iu! r/rr for 4 pariod from] minute to 2%

Tours.
For field installations, the instrumentation systems described in
Sections 2.1.1 and 2.1.2 were inounted inside standard 55-gallon stuel
druzs imbedded in concrete. Figure 2.1 i3 a block diagram of the detector
systams.
2.1.3Special Detector System.

A special detector system wes de~

signed and constructed todetermine the effects of high-garma rates and
DETECTOR HEAD
CRYSTAL

TIMING SIGNALS
:

—

Lae

GROUND
LEVEL

.

CONTROL
UNIT

FLIGHT PIPE
—wa

POWER
UNIT

RECORDER

PHCTOBULTIS
FLIER

imape 2,1 Block dingvren of a typle#l detuetor cysten. Tha dotacting
dlenant 49 oither a stiltens or an entbrac cna crystal “ipectirg on
whettor it da part of a lowe or a hignsstasitivity cystan.

cumulative exposures on the crystel datucting e@lecent. Two Ilsy-sonsitivity
detector Inads were enployed: one dm normal usece cad the eccond covered
with a Selinch*thick layer of lead shot to aticnuste the game rodistion
reaching the crystal by a factor of atcut 160, Tha “norsal™ head detected

is

SECRET

con tee

ere eee eee

Select target paragraph3