
April
2018
Pathfinder DVL Guide
Page 76
EAR-Controlled Technology Subject to Restrictions Contained on the Cover Page.
Transducer Inspection
Never set the transducer face on a rough surface; always use foam padding to protect the
transducer.
Based on experience, TRDI knows that most DVLs need to have the urethane inspected after 2 to 3 years
of field use. Many users are not familiar with the early signs of urethane failure. The primary damage to
the urethane is from bio-fouling and long exposure to the water and sun. Damage occurs on the surface of
the urethane and at the edge where the urethane bonds to the cup. By returning the system every 2 to 3
years, TRDI can inspect it for early signs of urethane failure and repair it through our Refurbishment Ser-
vice. At the same time, TRDI will make any necessary upgrades to boards, assemblies, and firmware. If
the Refurbishment Service is not needed, TRDI can upgrade the system as part of one of our Inspection
Services. Proper care, general maintenance, and this routine service period ensures that the Pathfinder
system lasts for a minimum of 10 years with no loss in performance.
As originally manufactured, the transducer face has a smooth surface that makes it
inhospitable for most biofouling to develop. Preserving this smooth surface is an effective
way to prevent heavy bio-growth on the transducer face. However, if an antifouling coating is
desired on the transducer face, then the face must be lightly abraded to allow the antifouling
coating to adhere.
As a rule, the surface must be kept smooth unless an antifouling coating
will be applied.
Removing Biofouling
To remove foreign matter and biofouling:
1. Remove soft-bodied marine growth or foreign matter with soapy water. Waterless hand cleaners
remove most petroleum-based fouling.
Do not use power scrubbers, abrasive cleansers, scouring pads, high-pressure marine cleaning
systems or brushes stiffer than hand cleaning brushes on the transducer faces. The urethane
coating on the transducer face could be damaged.
If there is heavy fouling or marine growth, the transducer faces may need a thorough cleaning to
restore acoustic performance. Barnacles do not usually affect Pathfinder operation, but TRDI does
recommend removal of the barnacles to prevent water leakage through the transducer face. Lime
dissolving liquids such as Lime-Away
®
break down the shell-like parts. Scrubbing with a medium
stiffness brush usually removes the soft-bodied parts. Do NOT use a brush stiffer than a hand
cleaning brush. Scrubbing, alternated with soaking in Lime-Away
®
, effectively removes large bar-
nacles.
If barnacles have entered more than 1.0 to 1.5 mm (0.06 in.) into the transducer face
urethane, send the Pathfinder to TRDI for repair. If the barnacles can not be removed without
damaging the transducer faces,
2. Rinse with fresh water to remove soap or Lime-Away
®
residue.
3. Dry the transducer faces with low-pressure compressed air or soft lint-free towels.
Always dry the Pathfinder before placing it in the storage case to avoid fungus or mold
growth. Do not store the Pathfinder in wet or damp locations.