APPLIED ACOUSTICS SYSTEMS 3510 PAM Portable, Operation Manual

Page: 57 / 74

PAM Portable Operation Manual
PAM-3510-8000/7
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F
AULT
/ S
YMPTOM
Short range
P
OSSIBLE
C
AUSE
Excessive range for conditions.
Range is dependent on local
conditions such as in-band noise from man-made or marine sources.
If possible reduce noise or work at a shorter range.
Beacon reply insensitivity.
This may be due to a fouled
transducer, or beacon fault. Clean beacon transducer with fresh
water. Try using another beacon.
Transducer reply insensitivity.
Check that the transducer is not
damaged or fouled. Clean transducer with fresh water.
Obstruction.
The beacon’s signal may be blocked by submerged
parts of the vessel, seabed objects – man-made and natural.
Bubbles of air and gas produced by the vessel’s propeller.
Thermoclines.
This is due to abrupt changes of velocity of sound in
water due to variances of water temperature and / or salinity. The
effect of this can be to ‘tunnel’ or bend the acoustic signal away from
either the target or the transducer. If possible try adjusting the height
of the transducer in the water.
F
AULT
/ S
YMPTOM
Unstable communications
P
OSSIBLE
C
AUSES
Transducer depth.
Transducer may not be deep enough in the
water. It is recommended the transducer be below the draft of the
vessel by at least 1 metre.
Interrogation rate too fast.
If the interrogation rate is too quick, it is
possible that reflections from previous signals may not have reduced
sufficiently, and are picked up first rather than the new signal.
Multipath interference.
This may be due to multipath interference
away from the transducer e.g. pipelines, underwater structures, and
thermoclines. If the sea is flat calm, it is common for the water / air
interface to give strong reflections. If possible try adjusting the height
of the transducer in the water.
Acoustic noise.
The noise can be vessel borne such as from the
propeller (try running at different revs), sonar systems (try
synchronising so that the sonar’s transmission does not overlap
Easytrak’s receive time. It is known in certain parts of the world for
marine animals to generate quite loud acoustic noise.
Electrical noise.
This can be conducted or radiated from
generators, welding kits, radio communications, sonar systems etc.
If possible, switch off equipment one system at a time until the
offending piece of equipment can be identified.
Battery Replacement
We recommend a maximum 3 year life for re-chargeable packs.
3510 Series Mini NiMH Battery Pack
14 cells at 1.2V / cell = 16.8V.
NOTE: -
Ensure that replacement battery packs are the same as the original type and complete the
battery pack information label. Refer to the label on the old pack.