18MA Transom Mount Transducer ?

[palmetto1]

Having trouble getting my new transducer to read at speed about 20mph.  Anyone have one mounted that reads really well at speed?  If so, love to know where it is and how far below the hull you have it.  The last one was a little further to the outside and when they mounted this on they came more toward the center which in looking under the boat may be in less clean water.  Ill post a pic of where mine is when the rain quits around here.