THE INSIDE STORY OF DIGITAL DEPTH FINDING You     have     just     purchased     the     most     useful     and sophisticated   digital   depth   instrument   on   the   marine market     today.          Utilizing     Aqua     Meter's     pioneering technology     in     shallow     water     depth-sounding,     and leadership   in   marine   instrumentation,   your   new   Aqua Probe^R digital will provide accurate valuable information, It    is    an    important    investment    in    helping    you    with navigating, piloting, and anchoring. You  already  may  be  familiar  with  other  types  of  depth sounding   equipment--flashers   and/or   graph   recorders- which  offer  you  a  wide  range  of  information.    If  so,  you will  be  accustomed  to  making  judgements  based  on  a "filtering" process your experience has taught your mind to make.  When you are given a choice of readings, you automatically decide which one, or ones, are useful and correct. For   example,   when   you're   using   one   of   the   popular flasher depth finders, your eye "sees" all the miscellaneous  signals  and  blips  displayed  on  the  dial. But  your  mind  registers  only  the  strong  signal  on  that portion  of  the  dial  in  which  reason  tells  you  the  correct depth   reading   is   located.      Your   judgmental   process categorizes    the    others    as    sub-surface    interference, thermal   layering,   or   fish   which   may   or   may   not   be important. Or,   when   you're   scanning   the   graph   from   a   charting recorder, you can identify the actual layers of interference,   or   fish,   along   with   the   contours   of   the bottom.    Your  mind  automatically  "averages"  the  bottom readings  into  a  useful  range  of  depth  information  and stores or rejects any other readings. Graphs and flashers, then, can simultaneously display a multitude of return signals for your interpretation. Conversely,   any   digital   depth   finder   operates   like   a computer  in  that  it  is  programmed  to  interpret  the  return signals  for  you,  and  will  display  only  the  depth  of  the strongest, shallowest echo.  Also, unlike the other types of  depth  instruments,  it  will  not  give  you  a  multitude  of returns from which to choose. In  fact,  a  great  deal  of  very  sophisticated  interference suppressing  circuitry  has  been  built  into  your  new  Aqua Probe    digital.        It    expressly    prevents    some    of    the extraneous  returns  which  are  normal  and  desirable  for the  flasher  or  graph,  from  interfering  with  the  primary purpose of the digital instrument-giving you the clearest, strongest, most correct and quickly-read bottom indication in large, clear, easy-to-read numerals. Teaching   you   how   to   achieve   these   results   is   the purpose of this manual. Contents The Inside Story of Digital Depth finding ..................2 Quick Tuning Procedures.........................................3 Installation................................................................5 Operation..................................................................9 Aqua Meter's Exclusive Technology ....................... 15 Navigating and Piloting .......................................... 16 Transducer Mounting.............................................. 19 Trouble Shooting Procedures................................. 21 Maintenance and Service........................................ 23 Summing Up ........................................................... 23 2