Ed
4-40
On the underwater shots, a zero-fiducial net provided the
experimenters with an accurate zero signal.
Voice-time equipment was installed at both Control Poiv*s
for broadcasting to all users of voice-time signals in synchronization with the timing sigrals.
The count-down was given
live from -60 minutes to -.5 ninutes.
At -15 minutes, tne tape
recorder started,
and *he count-down was given automaticarly
until zero time.
The Boxer and the Johnston Island voice-time
installations were similar.
When necessary, EG&G supplied users
with receiving ecuipment for the count-down.
The voice-count-
down was also patched into various user nets at the Control
Points.
These nets,
along with the radio signal nets, are —
listed in Table 2.
The timing and firing installation on the Boxer included
the automatic air-drop sequence timer used on Operation
Plumbbob.
Run time could be pre-set to any 1/10 second.
Signals were manually initiated at the control console from
-60 minutes to
-1 minute,
and the automatic timing sequence
began at -30 seconds when the verbal ‘go-ahead’ was received.
Both wire and radio signals were transmitted.
‘The JohnstonIsland system, originally, at Bikini, included
a sequence timer identical to:those at Eniwetok and Bikini.
This timer began the timing sequence and transmitted signals
automatically until a specified time prior to zero time.
A
"ready" signal from the launching site then started the new
automatic air-drop sequence timer,
which continued to transmit
timing signals through zero time.
The new air-drop timer was
similar to the one used on the Boxer except that it could be
enn
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