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INSTALLING THE TRANSDUCER

ECHO SOUNDER

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The transducer can be mounted in one of three ways:

(a)  The transducer face can be bonded directly to the inside of the hull.
      (some energy is lost to the hull but the loss in performance is, for
      most G.R.P  hulls, hardly noticeable).

(b) A through hull mount is available from your dealer or direct from
www.nasamarine.com.

(c) The transducer can be positioned inside a GRP hull by means of an In Hull
Transducer kit available from your dealer or direct from www.nasamarine.com

This method of installation has the dual advantage that no hole is made in the
vessels hull and that the echo sounder and transducer can easily be removed for
examination or installation elsewhere. It should be mentioned however, that
although the accuracy will in no way be affected by installing the transducer
inside the hull, the maximum range sensitivity may be reduced, depending on the
thickness and quality of the glass fibre. The In Hull Kit is available direct from
NASA Marine or your local chandler. Whichever is selected the best location still
has to be found.

Select a position below the water level where the transducer will point substanti-
ally towards the sea bed and where the transducer and cable are kept well 
clear of interference generating equipment. This position should be well clear of 
large masses of bubbles or cavitation which would disrupt the signal.

To test the suitability of the location, press a little sticky chewing gum on the 
surface of the transducer and stick it down to the inside of the hull (remove dirt 
and oily residue first). The  unit  can  then  be  tested. If the location is satisfactory
the chewing gum can be removed, and the transducer mounted using one of
the methods described previously. (Note: Do NOT shorten the transducer cable).

It is important that the face of the transducer is thoroughly bonded down to the 
hull. A single air bubble will cause a considerable loss in performance.

The transducer and the place of mounting must be kept entirely free of any
antifouling compound as this can also effect the performance of the unit. 

Summary of Contents for Cruiser Log

Page 1: ...ULTON ROAD STEVENAGE HERTS SG1 4QG ENGLAND 01438 354033 MARINE INSTRUMENTS Cruiser INSTALLTATION AND CONTEMPORARY STYLED INSTRUMENTS FOR CABIN OR COCKPIT MOUNTING USER INSTRUCTIONS for LOG DEPTH COMPA...

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Page 3: ...ly bonded to a tough plastic To keep it looking good clean only with a damp cloth Do not use abrasive cleaners or solvents INSTALLING THE DISPLAY 2 Cruiser instruments are waterproof when panel mounte...

Page 4: ...re The In Hull Kit is available direct from NASA Marine or your local chandler Whichever is selected the best location still has to be found Select a position below the water level where the transduce...

Page 5: ...and the red wire to the positive via a 1 4 amp fuse The red wire of the alarm is also connected to the positive supply whilst the black wire connects to the green wire from the display unit The alarm...

Page 6: ...eases The point at which the gain starts to rise is called the sensitivity threshold The sensitivity of the unit at depths below the sensitivity threshold will be considerably reduced whilst above the...

Page 7: ...e the hull is of constant thickness under the skin fitting flange so the nut will fit squarely against the hull The paddle wheel should be installed at a point in the hull where 1 It is immersed at al...

Page 8: ...e threads to seal the hull and to hold the nut securely in place The nut has a groove on its underside which should also be filled with silicone From the outside of the hull push the housing into the...

Page 9: ...ll and the position of the paddlewheel may affect the performence of the unit If the log under or over reads then the calibration factor can be adjusted to compensate Enter the Engineering mode by fir...

Page 10: ...led within the housing To accommodate pitch and roll motions most effectively mount the sensor as near to horizontal as possible For best performance in rough weather conditions it is also advisable t...

Page 11: ...ine at all times When the vessel s heading is within the pre set error limits the dead ahead indic ator is lit to show that all is well see Figure 3 and no steering adjustment is required This is the...

Page 12: ...ng indications If the error increases beyond 180 the error display reverses to show that the shortest route back to the desired heading is now using the opposite tiller SETTING THE DESIRED HEADING 0 0...

Page 13: ...n by the steering chevrons as shown on Figure 5 for two seconds when the key is released whereupon the display returns to the normal steering display SETTING OR STOPPING THE ALARM During assisted stee...

Page 14: ...nd by reference to Almanacs maps or charts The variation is the offset of magnetic North from true North If the Magnetic North the variation is West of true North enter it as a positive number Convers...

Page 15: ...heading indication 13 COMPASS ERROR CORRECTIONS In common with all magnetic compasses the presence of magnetic objects in the vessel can distort the earth s magnetic field nearby and affect the accur...

Page 16: ...has been logged When all the errors have been logged press UP and DOWN together to return to Engineering mode To exit Engineering press ENTER As a final test the vessel can be swung to confirm that th...

Page 17: ...n sequence as described If the error at a particular angle is known to be negligible there is no need to align the vessel and log the compensation at that position Additional corrections can be added...

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Page 20: ...e Nasa Marine Ltd will at its discretion repair or replace any components which fail in normal use within the warranty period Such repairs or replacements will be made at no charge to the customer for...

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