"Explain,
professor."
"Well, we can never do away with the noise of a sub's propulsion
machinery," Tom began. "That goes without saying. So we'll have to
camouflage it--lose it in the underwater jungle noises, so to speak."
Bud scratched his head. "How do we do that?"
"By amplifying the natural undersea sounds all about it," Tom explained.
"Fish and all forms of underwater life make a background noise over the
hydrophones, you know."
As Bud nodded, Tom went on, "So we simply step up the volume till the
sub's own noise gets drowned out or 'wasted' in all the racket."
This could be done, he concluded, with fairly simple amplifying
equipment. Bud, Hank, and Arv were jubilant at the idea.
"Nice going," Bud said. "How soon can we give it a try?"
"Soon as I can rig up the amplifier," Tom promised.
In less than two hours they were ready to submerge again. Zimby Cox
joined the crew. Bud suggested taking along hydrolungs in case of any
need for tinkering with the transducers or amplifying equipment.
This time, the jetmarine scored perfectly on the test, successfully
eluding all the _Sea Hound_'s efforts to detect it. Tom returned happily
to base, feeling that the antidetection problem was now solved. The
jetmarine, however, failed to appear.
"That's funny. The test was over at four-fifteen," Tom murmured.
Pages:
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96