Dukane DK120 - Manual (Page 15)

03-TM-0037 REV 13 Page 15 of 24
SECTION III
OPERATION
3.1. THEORY OF OPERATION.
3.1.1. The DK Series beacon is a battery-oper-
ated underwater acoustic pulse generator that is
activated when the water switch is immersed in
either fresh or salt water.
3.1.2. The water switch is part of a triggering
circuit, which when actuated will initiate normal
pulsing of the beacon circuit. The signal is
coupled to a piezo-ceramic transducer ring. This
results in mechanical motion that is transmitted
to the metal case of the beacon, which in turn,
radiates acoustic energy into the surrounding
water at 37.5 kHz.
3.1.3. The pulses generated are approximately 10
milliseconds in duration, and occur about once
per second in water. See Figure 15. The beacon
Figure 15. Nominal Pulse Train
will operate for a minimum of 30 days after
being immersed in the water. The beacon will
withstand depths to 20,000 feet (6096 meters). It
can be detected at a range of 2000 to 4000 yards
(1800 to 3600 meters). The sea state, nearby
boats, marine animals, gas or oil lines, and other
factors contributing to the ambient noise level
will affect the range at which the beacon can be
detected.